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The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Limited literature is available identifying phenotypical traits related to enteric methane (CH 4) production from dairy cows, despite its relevance in relation to breeding for animals with a low CH 4 yield (g/kg DMI) and the derived consequences hereof. This study aimed to investigate the relationships between CH 4 yield and different animal phenotypes when 16 second-parity dairy cows, fitted with a ruminal cannula, were fed 2 diets differing in forage/concentrate ratio in a crossover design. The diets had either a low forage proportion (35% on DM basis; F35) or a high forage proportion (63% on DM basis; F63). Gas exchange was measured by means of indirect calorimetry. Spot samples of feces were collected, and indigestible NDF (INDF) was used as an internal marker to determine total-tract digestibility. In addition, ruminal evacuations, monitoring of chewing activity, determination of ruminal VFA concentration, analysis of relative abundance of methanogens, and measurement of liquid passage rate were performed. Statistical differences were analyzed by a linear mixed model with diet, DIM, and period as fixed effects, and cow as random effect. The random cow estimates (RCE) were extracted from the model to get the Pearson correlations (r) between RCE of CH 4 yield and RCE of all other variables measured, in order to identify possible phenotypes related to CH 4 yield. Significant correlations were observed between RCE of CH 4 yield and RCE of OM digestibility (r = 0.63) and ruminal concentrations of valeric acid (r = −0.61), acetic acid (r = 0.54), ammonium (r = 0.55), and lactic acid (r = ‒0.53). Additionally, tendencies were observed for correlations between RCE of CH 4 yield and RCE of H 2 yield in g/kg DM (r = 0.47, P = 0.07), and ruminal isobutyric acid concentration (r = 0.43, P = 0.09). No correlations were observed between RCE of CH 4 yield and RCE of ruminal pool sizes, milk data, urinary measurements, or chewing activity. Cows had a lower DMI and ECM when they were fed F63 compared with F35. Cows fed F63 had higher NDF digestibility, CH 4 emissions (g/d, g/kg of DMI, and g/kg of ECM), ruminal concentration of acetic acid, ruminal pH, degradation rate of digestible NDF (DNDF, %/h), and longer rumen retention time (h). Rumination and total chewing time (min/kg DMI) were also higher for cows fed F63. The results in the present study emphasize the positive relation between a cow's ability to digest OM and their CH 4 emissions. The derived consequences of breeding for lower CH 4 emission might be cows with lower ability to digest OM, but more studies are warranted for further documentation of this relationship. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The 2 brown seaweeds, Fucus serratus and Fucus vesiculosus , have demonstrated antimethanogenic properties in vitro with reductions in CH 4 production ranging from 53 to 63%. This study aimed to investigate the effects of the 2 Fucus seaweeds on enteric CH 4 emissions, DMI, ECM, and nutrient digestibility when fed to dairy cows. The experiment was conducted using 4 multicannulated lactating Danish Holstein dairy cows, which over 3 experimental periods received either: (1) basal diet (CON; diet without any seaweed), (2) basal diet diluted with 4% (DM basis) Fucus serratus (SER), or (3) basal diet diluted with 4% (DM basis) Fucus vesiculosus (VES); resulting in one complete 3 × 3 Latin square and one incomplete 3 × 3 Latin square. Each period lasted 21 d and consisted of 14 d of adaptation, followed by 3 d of digesta sampling, and 4 d of gas exchange measurements using respiration chambers. Milk yield and feed intake were recorded daily. Blood samples were collected on d 15 and 17. All parameters were statistically analyzed using a mixed procedure of R. Opposite to what we had expected, neither of the 2 Fucus seaweeds reduced CH 4 emissions from the dairy cows as daily CH 4 production was significantly higher for both Fucus treatments compared with CON. Additionally, CH 4 yield (g CH 4 /kg DMI) and intensity (g of CH 4 /kg ECM) were significantly higher for SER compared with CON. Milk yield, DMI, and total-tract digestibility were unaffected by the treatments; however, SER resulted in lower milk protein yield (kg/d) and lower milk and blood plasma urea concentrations compared with CON. In conclusion, neither SER nor VES showed potential as methane-mitigating feed additives when fed to dairy cows at an inclusion level of 4% of DM. The inclusion of the 2 brown seaweeds had no effects on DMI, milk yield, or total-tract digestibility. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Mitochondrial dysfunction has been reported to occur in the mammary gland of dairy cows suffering from ketosis. Prohibitin 2 (PHB2) plays a crucial role in regulating mitophagy, which clears impaired mitochondria to maintain normal mitochondrial function. Therefore, the current study aimed to investigate how PHB2 mediates mitophagy, thereby influencing mitochondrial function in the immortalized bovine mammary epithelial cell line (MAC-T cells). First, mammary gland tissue and blood samples were collected from healthy cows (n = 15, BHB <0.6 m M) and cows with clinical ketosis (n = 15, BHB >3.0 m M). Compared with healthy cows, cows with clinical ketosis exhibited lower DMI, milk production, milk protein, milk lactose, and serum glucose. In contrast, milk fat, serum nonesterified fatty acids (NEFA) and BHB were greater in cows with clinical ketosis. The protein abundance of PHB2, peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α), mitofusin 2 (MFN2) in whole cell lysates (WCL), as well as PHB2, sequestosome-1 (SQSTM1, also called p62), microtubule-associated protein 1 light chain 3-II (MAP1LC3-II, also called LC3-II), and ubiquitinated proteins in mitochondrial fraction were significantly lower in cows with clinical ketosis. The ATP content of mammary gland tissue in cows with clinical ketosis was lower than that of healthy cows. Second, MAC-T were cultured and treated with NEFA (0, 0.3, 0.6, 1.2 m M). The MAC-T treated with 1.2 m M NEFA displayed decreased protein abundance of PHB2, PGC-1α, and MFN2 in WCL, as well as protein abundance of PHB2, p62, LC3-II, and ubiquitinated proteins in mitochondrial fraction. The content of ATP and JC-1 aggregates in 1.2 m M NEFA group were lower than in the 0 m M NEFA group. Additionally, 1.2 m M NEFA disrupted the fusion between mitochondria and lysosomes. The MAC-T were then pretreated with 100 n M rapamycin, followed by treatment with or without NEFA. Rapamycin alleviated impaired mitophagy and mitochondria dysfunction induced by 1.2 m M NEFA. Third, MAC-T were transfected with small interfering RNA to silence PHB2 or a plasmid for overexpression of PHB2, followed by treatment with or without NEFA. The silencing of PHB2 aggravated 1.2 m M NEFA-induced impaired mitophagy and mitochondrial dysfunction, whereas the overexpression of PHB2 alleviated these effects. Overall, this study provides evidence that PHB2, in regulation of mitophagy, is a mechanism for bovine mammary epithelial cells to counteract NEFA-induced mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Introduction: During the time around parturition, animals make many metabolic adjustments to support the transition from pregnancy to lactation (Mullins et al. 2012). In addition, dairy cattle produce milk more than their ability to consume energy, as a result, they are in a negative energy balance at the beginning of lactation, which may reduce the longevity of the cattle in the herd and increase the rate of elimination of dairy cattle (Vallimont et al. 2001). Heat stress in late pregnancy is aggravated by energy restriction. In such conditions, the use of management and nutritional methods will reduce the problems during the transfer period and heat stress (Duffield et al. 2012). One of the ways to optimize the productive and reproductive conditions of livestock, through improving the metabolism of nutrients and eliminating or reducing stress conditions, is to use chromium as a metabolic improver (Meyer et al. 2012). Scientific sources suggested the amount of chromium needed for sheep 3 to 5 mg per day and for dairy cows 15 to 50 mg per day. Inorganic chromium has a bioavailability of about 0.5 percent. While organic chromium has more than 25 percent intestinal absorption, and therefore, consumption of inorganic chromium is not recommended due to its low bioavailability and toxic effects (Lashkari et al. 2018). Among the sources of organic chromium, chromium-methionine has been recognized by important global food and drug organizations as a compound with high bioavailability, impressive metabolic responses and no toxicity complications (Mousaie et al. 2014). Materials and Methods: This experiment was conducted to investigate the effect of using different forms of chromium around calving on feed consumption, nutrient digestibility, nutritional behavior of Afshar ewes and the performance of their lambs under the influence of heat stress. Forty pregnant Afshari ewes were assigned to four experimental treatments with ten replications from 42 ± 5 days before the expected birth in a completely randomized design. Experimental treatments include: 1) basic diet without chromium supplementation (control), 2) basic diet containing 3 mg of chromium in mineral form per kg of dry matter, 3) basic diet containing 3 mg of chromium in the form of chromium-methionine per kg Each kilogram of dry matter and 4) the basic diet contained 3 mg of chromium in the form of chromium nanoparticles per kilogram of dry matter. The length of the test period was 84 days. Weighing of ewes was done at the beginning, at the time of calving and at the end of the period. The rest of the feed is weighed every day and the daily feed consumption was calculated by deducting from the provided feed. In order to measure the digestibility of ewes, stool and feed samples were collected for 5 days from 10 to 6 days before possible calving and 31 to 35 days after calving. To determine the chemical composition of food and feces samples (dry matter, crude protein, crude fat, and organic matter), the methods of the official association of analytical chemists were used. The insoluble fiber in neutral detergent (NDF) and the insoluble fiber in acid detergent (ADF) were also determined by the Van Soest method. In relation to feed consumption behavior during 28 to 30 days after birth, it was measured as a 24-hour activity record. The time spent for the activities of eating, resting, standing and ruminating was recorded visually every 5 minutes and assuming that the activity continued in the last 5 minutes for all the animals during the day and night hours. After birth, the lambs were first dried and weighed after performing the necessary hygiene operations, and then they received the first portion of colostrum. Diarrhea status and duration of diarrhea and stool score were recorded daily. Stool scores were determined based on 1_ hard and consistent, 2_ soft and loose, 3_ loose and watery, 4_ watery with some blood and 5_ watery with blood and mucus. A digital thermometer was used to measure the rectal temperature. The thermometer was placed in the animal's rectum for 3 minutes and the temperature was recorded immediately. Respiration rate was measured by visual observation of the number of ups and downs of the animal's side in one minute. In order to measure the apparent digestibility of dry matter in lambs, feed and feces samples were sampled on the 35th day after birth using acidinsoluble ash (AIA) as an internal marker for six consecutive days. Results and Discussion: The results showed that there was no significant difference in the weight of the ewes before calving. But from the beginning of ewes giving birth (P=0.0466) to 6 weeks after giving birth (P=0.0484), the treatments receiving different forms of chromium performed better than the control group of ewes. Dry matter consumption of ewes also had an upward trend from the third to the sixth week after giving birth in the ewes receiving chromium-methionine and chromium nanoparticles (P < 0.05). The digestibility of dry matter and insoluble fibers in neutral detergent increased during the period before and after the delivery of ewes under the influence of chromium intake (P=0.0001). Addition of chromium supplement to the diet of ewes did not cause a significant difference in the parameters of feed consumption behavior, but it caused a significant difference in the resting behavior of the ewes, so that the lowest and longest resting time was related to the treatment receiving chromium nanoparticles and the control, respectively (P=0.0411). Adding chromium supplement to the diet of ewes improves the birth weight, daily weight gain, digestibility and diarrhea condition of the born lambs (P<0.05). Conclusion: In general, it is recommended to receive chromium, especially in the form of chromium-methionine and chromium nanoparticles, during the transition period of ewes under the influence of heat stress. [ABSTRACT FROM AUTHOR]

Simple Summary: Enzymatically hydrolysed yeast is a novel form of yeast culture with positive effects as prebiotics used to improve gastrointestinal health in ruminants. However, their effect on ruminal nutrient digestion is unclear. This study evaluated the effects of a combined yeast culture and enzymatically hydrolysed yeast on dry matter, fibre, and crude protein ruminal digestibility in vitro. Seven different substrates inclusive of legume and grass forages and commercial supplemental feedstuffs were incubated for 24 and 48 h, with or without enzymatically hydrolysed yeast, and again for 0, 2, 4, 8, 16, 24, and 48 h to determine crude protein degradability. Enzymatically hydrolysed yeast improved the fibre digestion of Brachiaria arrecta by 32%, while the dry matter and crude protein digestibility in soybean meal and Glircidia sepium were reduced by 16.2% and 38.5%, respectively, after 24 h of incubation. Therefore, enzymatically hydrolysed yeast has potential to improve ruminal fibre digestibility and modify the crude protein degradation of different substrates, which may contribute to the improved utilization of fibrous feedstuffs and efficiency in nitrogen and crude protein metabolism in ruminants. Live yeast cultures have been a popular additive in ruminant feeds to improve fermentation efficiency, rumen, and intestinal health. However, very little is known about inactive yeast culture and hydrolysable yeast cells on nutrient digestibility in ruminants. Therefore, this study was conducted to determine the effects of a combined yeast culture and enzymatically hydrolysed yeast (YC+EHY) on in vitro dry matter and nutrient digestibility. Seven chemically contrasting substrates, including the leaves and petiole of forage plants (Trichanthera gigantea, Gliricidia sepium, Leucaena leucocephala, and Brachiaria arrecta), agriculture by-products (soybean meal and rice hulls), and a commercial concentrate feed, were incubated in vitro with and without YC+EHY to determine dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), and acid detergent fibre (ADF) digestibility after 24 and 48 h of incubation. A second experiment evaluated in vitro CP degradability by incubating substrates for 0, 2, 4, 8, 16, 24, and 48 h with and without YC+EHY. Incubation with YC+EHY reduced 24 h DM and CP digestibility in soybean meal and G. sepium by 16.2% and 38.5%, respectively. Conversely, the ADF digestibility of B. arrecta incubated with YC+EHY increased by 32%. In vitro ruminal DM and nutrient digestibility were unaffected by YC+EHY after 48 h of incubation. The rate of CP degradability in the commercial concentrate and rice hull inoculated with YC+EHY increased sharply between 16 and 24 h post-incubation and generally plateaued afterwards. Similarly, YC+EHY significantly increased CP degradability in L. leucocephala after 8 and 16 h of incubation. The 16 h CP degradation in T. gigantea without YC+EHY was significantly higher. It was therefore concluded that YC+EHY has potential to improve ruminal ADF digestibility and modify ruminal CP degradation dependent on the type of substrate. [ABSTRACT FROM AUTHOR]

The article "Activity of the Hura crepitans (Linn.) seeds as gastrointestinal antiparasitic in fattening lambs" published in the Indian Journal of Traditional Knowledge explores the potential of Hura crepitans seeds as an antiparasitic treatment for lambs. The study conducted by researchers from various institutions in Mexico and Spain analyzed the effects of different doses of the seeds on lambs' vital signs, blood cells, proteins, and enzymes over a period of five days. The findings provide valuable insights into the potential use of Hura crepitans seeds as a natural antiparasitic agent in livestock management. [Extracted from the article]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Maternal (F 0) exposure to late-gestation heat stress reduces their daughter's (F 1) mammary gland fat pad (FP) mass, parenchyma (PAR) mass, and epithelial cell proliferation when evaluated at birth and weaning, and the daughters go on to produce less milk in their first lactation. Herein, we investigated the effect of maternal late-gestation heat stress on whole-body growth and mammary development of their granddaughters (F 2). Multiparous F 0 cows had access to heat abatement (n = 41, shade, and active cooling via fans and water soakers) or not (n = 41, shade only) for the last 56 d of gestation during a subtropical summer. Consequently, the F 1 daughters, born to F 0 cows, were heat-stressed (HT F1 , n = 36) or cooled (CL F1 , n = 37) in utero during the last 2 mo of gestation. All F 1 heifers were raised as an identically managed cohort until first calving. The F 2 granddaughters, born to HT F1 (HT F2 , n = 12) or CL F1 (CL F2 , n = 17), were raised as an identically managed cohort until 70 d of age. Dry matter intake, BW, hip height, wither height, chest girth, head circumference, mammary gland teat length, and left–right and front–rear teat distances were measured. Average daily gain was calculated for the preweaning period (0–49 d). Mammary ultrasounds were performed on d 21, 49, and 70 (n = 9/group) on the rear left and right quarters to quantify PAR and FP areas. Mammary biopsies were collected for histological evaluation of epithelial structures (hematoxylin and eosin staining), and to quantify cells positive for estrogen receptor, α subunit (ERα), cell proliferation (Ki67), and apoptosis (terminal deoxynucleotidyl transferase dUTP nick-end labeling, TUNEL). Heifer growth from birth to d 49 was similar between CL F2 and HT F2 for all parameters evaluated. Distances between teats and teat length were not different between groups. On d 70, CL F2 heifers tended to have a greater average PAR (right and left quarters) relative to HT F2 heifers. Although the left FP was smaller in HT F2 heifers relative to CL F2 heifers, the average FP was not different. The lumenal and nonlumenal epithelial structures in the PAR of HT F2 heifers were significantly smaller than those of CL F2 heifers. In addition, HT F2 heifers had a reduced percentage of proliferating cells in the epithelial and stromal compartments and a greater percentage of apoptotic cells, particularly in the stroma. The percentage of ERα positive cells was significantly reduced in HT F2 heifers. In summary, although HT F2 heifers' DMI was similar and they grew at the same rate as CL F2 heifers throughout the preweaning phase, their mammary glands had smaller PAR areas with fewer epithelial structures characterized by reduced cell turnover and lower ERα expression. These early changes in the microstructure and cellular turnover of the mammary gland may partly explain the reduction in lactation performance relative to CL F2 counterparts at maturity. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Following a comparison of nutrient total-tract digestibility estimates in lactating buffaloes using single-point undigestible NDF (uNDF) or acid-insoluble ash (AIA) as internal markers, the potential of fecal near-infrared spectroscopy (NIRS) to provide calibration equations for the assessment of the chemical composition of feces and nutrient total-tract digestibility estimated with internal markers was explored. Chemical analyses were performed on 147 fecal samples from lactating buffaloes reared on 5 farms in central Italy (Naples). Each farm fed a silage-based TMR to the buffaloes, and the TMR was sampled in the 2 d before the fecal collection. The TMR and individual fecal samples were collected and analyzed for DM, OM, ash, AIA, ether extract (EE), starch, fiber fractions (amylase-treated NDF without residual ash [aNDFom], amylase-treated NDF inclusive of residual ash [aNDF], ADF without residual ash [ADFom], ADF, hemicellulose, cellulose, ADL, uNDF), N, CP and CP bound to aNDF (NDICP) and to ADF (ADICP). The uNDF content was determined through a 240-h in vitro fermentation and employed, together with AIA as markers, to estimate the total-tract apparent digestibility and total-tract digestibility of DM, OM, ash, N, CP, EE, aNDFom, aNDF, NDIP, ADFom, and ADF, ADIN, ADL, hemicellulose, cellulose, starch, NFC, and the B3 fraction of N (NB3). No correlation was found between DM and OM digestibility estimated with AIA and uNDF as internal markers. Weak correlations were detected for all the other nutients digestibilities, and strong correlations were observed for EE, ADFom, hemicellulose, NDIN, ADIN, NB3, NFC, and starch. The sample set (n = 147) was divided in a calibration set (n = 111) and a validation set (n = 36) to "train" and "validate" the fecal NIRS curve through an external validation process. An estimation usable for preliminary or initial evaluation was obtained for N, CP, and aNDF fecal content. An excellent prediction was obtained for total tract digestibility of ADIN (R2 = 0.90) when estimated with uNDF as the internal marker. The NIRS technology was not able to accurately predict all the other traits and the estimated nutrient digestibility of lactating buffalo diets from fecal spectra. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the effects of various chemical treatments on the in vitro dry matter digestibility (IVDMD) and concomitant feed value of dried grape pomace (DGP). Sun-dried grape pomace, derived from grapes processed in Denizli, Türkiye province was used in the experiment. One control group and three treatment groups were established, each with eight replicates. The first, second and third experimental groups were treated with 1.5% ammonia (NH3 ), 3% urea (CH4 N2O) and 3% sodium hydroxide (3%) (NaOH), respectively. The dry matter content was set at 50% for all groups. The control group received no additional chemicals. All groups were kept in airtight, closed plastic bags at room temperature for one week. Adding NH3 and CH4 N2O significantly improved crude protein levels (24.45 and 19.84%, respectively) and in vitro protein degradability (59.84 and 65.69%, respectively) in the experimental groups (p<0.001). Treatment with CH4 N2O did not exert the same deleterious effect on the ether extract concentration of desiccated grape pomace (p<0.004) as treatment with NaOH. Moreover, relative feed value declined significantly more after NaOH treatment compared to treatments containing nitrogen (p<0.001). Additionally, NaOH treatment yielded the lowest in vitro protein degradability of DGP at 40.32% (p<0.001). With an in vitro dry matter degradability of 47.18%, the findings indicate that among the chemical treatments investigated, application of NH3 resulted in the lowest degradability value (p<0.001). Consequently, it can be inferred that the feed value and digestibility of desiccated grape pomace are highly influenced by the nitrogen concentration or basic nature of the supplemental chemical compounds. [ABSTRACT FROM AUTHOR]

Background: C16:0 and cis-9 C18:1 may have different effects on animal growth and health due to unique metabolism in vivo. This study was investigated to explore the different effects of altering the ratio of C16:0 and cis-9 C18:1 in fat supplements on growth performance, lipid metabolism, intestinal barrier, cecal microbiota, and inflammation in fattening bulls. Thirty finishing Angus bulls (626 ± 69 kg, 21 ± 0.5 months) were divided into 3 treatments according to the randomized block design: (1) control diet without additional fat (CON), (2) CON + 2.5% palmitic acid calcium salt (PA, 90% C16:0), and (3) CON + 2.5% mixed fatty acid calcium salt (MA, 60% C16:0 + 30% cis-9 C18:1). The experiment lasted for 104 d, after which all the bulls were slaughtered and sampled for analysis. Results: MA tended to reduce 0–52 d dry matter intake compared to PA (DMI, P = 0.052). Compared with CON and MA, PA significantly increased 0–52 d average daily gain (ADG, P = 0.027). PA tended to improve the 0–52 d feed conversion rate compared with CON (FCR, P = 0.088). Both PA and MA had no significant effect on 52–104 days of DMI, ADG and FCR (P > 0.05). PA tended to improve plasma triglycerides compared with MA (P = 0.077), significantly increased plasma cholesterol (P = 0.002) and tended to improve subcutaneous adipose weight (P = 0.066) when compared with CON and MA. Both PA and MA increased visceral adipose weight compared with CON (P = 0.021). Only PA increased the colonization of Rikenellaceae, Ruminococcus and Proteobacteria in the cecum, and MA increased Akkermansia abundance (P < 0.05). Compared with CON, both PA and MA down-regulated the mRNA expression of Claudin-1 in the jejunum (P < 0.001), increased plasma diamine oxidase (DAO, P < 0.001) and lipopolysaccharide (LPS, P = 0.045). Compared with CON and MA, PA down-regulated the ZO-1 in the jejunum (P < 0.001) and increased plasma LPS-binding protein (LBP, P < 0.001). Compared with CON, only PA down-regulated the Occludin in the jejunum (P = 0.013). Compared with CON, PA and MA significantly up-regulated the expression of TLR-4 and NF-κB in the visceral adipose (P < 0.001) and increased plasma IL-6 (P < 0.001). Compared with CON, only PA up-regulated the TNF-α in the visceral adipose (P = 0.01). Compared with CON and MA, PA up-regulated IL-6 in the visceral adipose (P < 0.001), increased plasma TNF-α (P < 0.001), and reduced the IgG content in plasma (P = 0.035). Compared with CON, PA and MA increased C16:0 in subcutaneous fat and longissimus dorsi muscle (P < 0.05), while more C16:0 was also deposited by extension and desaturation into C18:0 and cis-9 C18:1. However, neither PA nor MA affected the content of cis-9 C18:1 in longissimus dorsi muscle compared with CON (P > 0.05). Conclusions: MA containing 30% cis-9 C18:1 reduced the risk of high C16:0 dietary fat induced subcutaneous fat obesity, adipose tissue and systemic low-grade inflammation by accelerating fatty acid oxidative utilization, improving colonization of Akkermansia, reducing intestinal barrier damage, and down-regulating NF-κB activation. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of different processing methods (steam-flaking, micronized and micronized-flaking; F, M, and MF, respectively) of corn grains on various factors including water absorption index (WAI), damaged starch content (DSC), nutrient digestibility, gas production (GP), microbial crude protein (MCP) and effective utilizable crude protein (EUCP). Flaked treatments (F and MF) were used in whole, cracked and ground forms (1.5- and 3-mm), while non-processed corn grains (G) and M were only ground. All MF treatments showed higher ruminal digestibility of dry matter (DM) and starch, GP, as well as increased MCP and EUCP compared to other treatments (P<0.001). The F treatment in the whole form and ground micronized corn showed significantly lower (P<0.001) ruminal digestibility of DM and starch, as well as GP and MCP. However, the above two treatments exhibited greater in vitro disappearances of DM and starch in the small intestine. It can be concluded that post-flaking of infrared radiated corn may induce severe ruminal degradation above that of steam flaking. Therefore, a flake density greater than 0.41 kg/L may be appropriate for micronized-flaked corn when used in its whole form to achieve optimum ruminal degradation and maximum digestibility of starch in the small intestine. [ABSTRACT FROM AUTHOR]

The study aims to characterize the robustness of distinct clinical assessments in identifying the underlying conditions of dry eye disease (DED), with a specific emphasis on the involvement of conjunctival goblet cells. Seven rabbits receiving surgical removal of the lacrimal and Harderian glands were divided into two groups, one with ablation of conjunctival goblet cells by topical soaking of trichloroacetic acid (TCA) to the bulbar conjunctiva (n = 3) and one without (n = 4), and the conditions of DED were assessed weekly using Schirmer test, tear breakup time (TBUT), tear osmolarity, and National Eye Institute (NEI) fluorescein staining grading. After 8 weeks, the rabbits were sacrificed, and the eyes were enucleated for histopathological examination. Histopathological analysis revealed corneal epithelial thinning in both groups. While TCA soaking significantly decreased the density of conjunctival goblet cells, DED rabbits without TCA also showed a partial reduction in goblet cell density, potentially attributable to dacryoadenectomy. Both groups showed significant decreases in Schirmer test and TBUT, as well as an increase in tear osmolarity. In DED rabbits with TCA soaking, tear osmolarity increased markedly, suggesting that tear osmolarity is highly sensitive to loss and/or dysfunction of conjunctival goblet cells. Fluorescein staining was gradually and similarly increased in both groups, suggesting that fluorescein staining may not reveal an early disruption of the tear film until the prolonged progression of DED. The Schirmer test, TBUT, tear osmolarity, and NEI fluorescein grading are distinct, yet complementary, clinical assessments for the evaluation of DED. By performing these assessments in definitive DED rabbit models, both with and without ablation of conjunctival goblet cells, the role of these cells in the homeostasis of tear osmolarity is highlighted. Characterizing the robustness of these assessments in identifying the underlying conditions of DED will guide a more appropriate management for patients with DED. [ABSTRACT FROM AUTHOR]

3D human tissue models/microphysiological systems (3D/MPS) can represent human physiology. Linking organ models can improve biological fidelity and predictive capability. 3D/MPS may be infected with HIV, enabling studies of pathogenesis, host–virus interactions, inflammation, neuropathogenesis, and HIV reservoirs. Integrating immune cells or lymphoid tissues into 3D/MPS facilitates study of HIV immune responses, leukocyte depletion, immune ontogeny, immunotherapies, and vaccines. Application of 3D/MPS to therapeutic development facilitates sophisticated preclinical pharmacology, in silico modeling, predictions of human response and safety, and evaluation of potency of biologics. Tissue sources and/or modifications permit study of unique conditions, including TB co-infection, substance use, and special populations (e.g., medically fragile, pregnant or lactating people, and children). Three-dimensional (3D) human tissue models/microphysiological systems (e.g., organs-on-chips, organoids, and tissue explants) model HIV and related comorbidities and have potential to address critical questions, including characterization of viral reservoirs, insufficient innate and adaptive immune responses, biomarker discovery and evaluation, medical complexity with comorbidities (e.g., tuberculosis and SARS-CoV-2), and protection and transmission during pregnancy and birth. Composed of multiple primary or stem cell-derived cell types organized in a dedicated 3D space, these systems hold unique promise for better reproducing human physiology, advancing therapeutic development, and bridging the human–animal model translational gap. Here, we discuss the promises and achievements with 3D human tissue models in HIV and comorbidity research, along with remaining barriers with respect to cell biology, virology, immunology, and regulatory issues. [ABSTRACT FROM AUTHOR]

Simple Summary: The strategic supplementation of cattle in an intensive production system seeks to maximize intake and improve tropical forage digestibility, improving production performance per area. In this sense, the use of coproducts, such as distillers grains, becomes an economical alternative due to their lower cost in relation to other traditionally used ingredients. The aim of this study was to evaluate the effects of including high-protein distillers dried grains (HP-DDG; 430 g/CP) in supplements for beef cattle in an intensive grazing finishing system. Five uncastrated male Nellore cattle with an average body w (BW) of 413.5 ± 32 kg were used in a 5 × 5 Latin square design. High-protein distillers' dried grain (HP-DDG) does not affect the total voluntary intake of beef cattle when replacing soybean meal (SBM). Pasture dry matter intake does not change. Urinary nitrogen excretion decreased with the inclusion of HP-DDG. HP-DDG decreases the proportion of nitrogen compounds that are recycled to the rumen. The objective was to evaluate the effects of including high-protein distillers dried grains (HP-DDG; 430 g/CP) in supplements for beef cattle in an intensive finishing pasture system. Five Nellore bulls with an average body weight (BW) of 413.5 ± 32 kg were distributed in a 5 × 5 Latin square design. The animals were randomly allocated to Marandu palisade grass paddocks (Urochloa brizantha cv. Marandu), with 0.32 ha each. Protein-energy supplements were evaluated and formulated with different replacement levels (0, 250, 500, 750 and 1000 g/kg) of soybean meal (SBM) by HP-DDG. Supplements were offered once a day in the amount of 6.0 kg/animal. Replacing SBM with HP-DDG had no effect (p > 0.10) on the intake of total and pasture DM, OM, CP, NDFap, digestible organic matter (DOM), metabolizable protein and CP:DOM ratio. Total and pasture DM intake averaged 6.07 and 11.54 kg/day, respectively. Replacing SBM with HP-DDG reduces and increases, respectively, the intake of degradable (RDP) and undegradable (RUP) protein in the rumen (p < 0.10) with a consequent linear reduction in ruminal ammonia concentration (RAN), nitrogen excretion in urine and serum N concentration (SUN) (p < 0.10). In supplements offered in the amount of 6.0 kg animal/day, SBM can be completely replaced by HP-DDG. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) signaling is known to be involved in the antidepressant‐like effects of conventional antidepressants, such as desipramine (DMI), a tricyclic antidepressant, and fluoxetine (FLX), a selective serotonin reuptake inhibitor; however, the precise role of neuronal VEGF signaling in mediating these effects remains unclear. Using mice with excitatory neuron‐specific deletion of VEGF and its receptor, fetal liver kinase 1 (Flk‐1) in the forebrain, we examined the effects of forebrain excitatory neuron‐specific deletion of VEGF or Flk‐1 on the antidepressant‐like effects of repeated DMI and chronic FLX administration in the forced swim test (FST). Repeated intraperitoneal (i.p.) injections of DMI (10, 10, and 20 mg/kg at 24, 4, and 1 h before the FST, respectively) significantly decreased immobility in control mice; however, this effect was completely blocked in mice with neuron‐specific VEGF or Flk‐1 deletion. Although chronic treatment with FLX (18 mg/kg/day, i.p.) did not impact immobility in control mice 1 day after the 22nd injection, immobility was significantly reduced 1 day after the preswim and the 23rd FLX injection. However, in mice with neuron‐specific Flk‐1 deletion, chronic FLX treatment significantly increased immobility in the preswim and failed to produce antidepressant‐like effects. Collectively, these findings indicate that neuronal VEGF–Flk‐1 signaling contributes to the antidepressant‐like actions of conventional antidepressants. [ABSTRACT FROM AUTHOR]

We used published data consisting of 263 treatment mean observations from beef cattle and dairy steers and heifers, in which CH4 was measured via chambers or head boxes, to evaluate relationships between enteric CH4 production and dry matter intake (DMI) and dietary components. Daily DMI was positively related (slope = 15.371, p < 0.001) to total daily production (g/d) of CH4 (r2 = 0.821). Among chemical components, dietary neutral detergent fiber (NDF) concentration was the most highly related (r2 = 0.696; slope = 0.2001; p < 0.001) to CH4 yield (g/kg of DMI), with strong relationships also noted for dietary starch:NDF ratio (r2 = 0.662; slope = −2.4587; p < 0.001), starch (r2 = 0.495; slope = −0.106; p < 0.001), and the proportion of metabolizable energy relative to gross energy (r2 = 0.561; slope = −23.663; p < 0.001). The slope (−0.5871) and intercept (22.2295) for the dietary ether extract vs. CH4 yield were significant (p < 0.001), but the relationship was highly variable (r2 = 0.150). For dietary crude protein concentration, the slope for CH4 yield was not significant (−0.0344; p < 0.381) with an r2 value near zero. Decreasing DMI by programming body weight gain or restricting feed intake could decrease CH4 production in confined cattle, but these approaches might negatively affect growth performance and product quality, potentially negating positive effects on CH4 production. Feeding higher-quality forages or using grazing management systems that decrease dietary NDF concentrations or substituting grain (starch) for forage should decrease both CH4 yield from enteric production and manure CH4 production via increased digestibility. Effects of feeding management and diet formulation strategies should be additive with other mitigation approaches such as feed additives, allowing the cattle industry to achieve maximal decreases in enteric CH4 production, while concurrently maintaining optimal beef production. [ABSTRACT FROM AUTHOR]

Simple Summary: There is increasing evidence that feeding a garlic and citrus extract supplement (GCE) to dairy cows could reduce enteric methane emissions and improve milk production. However, there is a lack of information on the effect of feeding with this supplement on the production performance of grazing cows. In a study conducted on a Chilean commercial farm, two experiments examined the impacts of feeding with GCE on the milk production performance and carbon footprint of grazing cows in the early- to mid-lactation and late-lactation stages. In both experiments, grazing cows were offered a supplementary concentrate without or with GCE (33 g/cow/d). Feeding with GCE increased feed intake and improved milk production, feed efficiency and lactation persistency in early- to mid-lactation and late-lactation grazing cows. Simulation of life cycle assessment indicated that the impacts of GCE on milk production efficiency resulted in a lower carbon footprint for milk. Thus, this study demonstrated that feeding with GCE could be a viable nutritional solution for improving sustainable dairy production in grazing systems. Two trials were conducted to evaluate the effect of a garlic and citrus extract supplement (GCE) on the milk production performance and carbon footprint of grazing dairy cows in a Chilean commercial farm. A total of 36 early- to mid-lactation and 54 late-lactation Irish Holstein-Friesian cows were used in Trial 1 and Trial 2, respectively. In both trials, the cows were reared under grazing conditions and offered a supplementary concentrate without or with GCE (33 g/cow/d) for 12 weeks. The concentrate was fed in the afternoon when the cows visited the milking parlour. Consequently, the results of milk production performance in these trials were used to determine the effect of feeding with GCE on the carbon footprint (CFP) of milk using a life cycle assessment (LCA) model. In Trial 1 and Trial 2, feeding with GCE increased estimated dry matter intake (DMI, kg/d) by 8.15% (18.4 vs. 19.9) and 15.3% (15.0 vs. 17.3), energy-corrected milk (ECM, kg/d) by 11.4% (24.5 vs. 27.3) and 33.5% (15.5 vs. 20.7), and feed efficiency (ECM/DMI) by 3.03% (1.32 vs. 1.36) and 17.8% (1.01 vs. 1.19), respectively. The LCA revealed that feeding with GCE reduced the emission intensity of milk by 8.39% (1.55 vs. 1.42 kg CO2-eq/kg ECM). Overall, these results indicate that feeding with GCE improved the production performance and CFP of grazing cows under the conditions of the current trials. [ABSTRACT FROM AUTHOR]

A study was carried out for a period of 4 months to evaluate the effect of dietary inclusion of garden cress (GC) seeds on growth performance and nutrient digestibility in New Zealand White rabbits. Eighteen New Zealand White female rabbits of four months of age were selected and were divided into three groups of six animals each based on age and body weight. The animals were randomly allotted to three dietary treatments, T1 (control diet with 18 per cent CP and 2700 kcal DE), T2 (concentrate with 5 per cent GC seed on dry matter basis) and T3 (concentrate with 7.5 per cent GC seed on dry matter basis). Data analysis revealed that the growth performance and nutrient digestibility of dry matter, crude protein and ether extract were similar among treatment groups. Furthermore, dietary treatments had no effect on blood biochemical parameters. From the overall results, it can be concluded that GC seeds can be safely incorporated up to 7.5 per cent in rabbit diet without compromising the health status and growth performance in New Zealand White rabbits. [ABSTRACT FROM AUTHOR]

Introduction: Plant-based (vegan) diets for dogs are commercially available, however, research investigating long-term nutritional adequacy of these diets is scarce. Use of client-owned animals has become increasingly popular for apparent total-tract nutrient digestibility (ATTD) studies, yet low guardian compliance with the study protocol, such as providing daily dietary intake information, is a challenge. However, the impact of low diet reporting compliance on the overall ATTD results is unknown. Methods: Sixty-one, client-owned healthy adult dogs completed a randomized, double-blinded longitudinal study. Dogs were randomly assigned into two groups that were fed either a commercial extruded meat-based diet (MEAT, n=30) or an experimental extruded vegan diet (PLANT, n=31) for 12 weeks. At the end of the study, pet guardians performed a 72-hour total fecal collection for ATTD assessment. Pet guardians were asked to complete a food diary for the duration of the trial, however only a subset of guardians (n=35) provided this food diary at the end of the study. Results: No evidence of an association between pet guardians providing a food diary and apparent digestibility coefficients (ADC) of crude protein (CP) (p=0.14), crude fat (EE) (p=0.72), and dry matter (DM) (p=0.68) was found. Apparent digestibility coefficients for CP (p=0.52), EE (p=0.78), and DM (p=0.43) did not differ between PLANT and MEAT. Body weight and age were found to be associated with CP (p=0.03) and DM (p=0.01) digestibility, but no association with EE (p=0.07) digestibility was present. Discussion: These results indicate that vegan- and animal-based diets with similar nutrient profiles can have comparable nutrient digestibility. Moreover, presence or absence of a guardian-reported food diary had no effect on the overall results of the ATTD study. Further studies investigating guardian compliance for ATTD trials are needed to develop a standardized protocol and reduce current challenges and limitations related to pet guardian’s participation in digestibility trials. [ABSTRACT FROM AUTHOR]

Legumes shrubs such as Cratylia argentea have an ability to thrive in environments with low water availability and poor soil. On the other hand, forage grasses such as Tifton 85 have a greater demand for inputs to be productive. The objective of this study was to evaluate the performance of growing and finishing Lacaune lambs fed Cratylia argentea hay as an alternative to Tifton 85 (Cynodon spp). Twenty-four Lacaune lambs aged between five and six months (average body weight [BW] 21.50 ± 3.38 kg) were arranged in a split-plot randomized block design. The plots consisted of different Cratylia to Tifton 85 hay proportions (0, 20%, 40%, or 100%, dry matter [DM] basis) as a roughage replacement in the total diet. The subplots represented two evaluation times, entitled "initial period" and "final period", which consisted of the early seven days of total feces and urine collection, and the last seven days of the experiment, respectively. The lambs were blocked by weight with six replicates per treatment. The results show that the level of Tifton 85 replacement for Cratylia hay in the roughage portion of the lamb diet did not influence (P > 0.05) weight gain (WG), dry matter intake or dry matter digestibility; feed conversion, feed efficiency; and the evaluated nitrogen balance variables. The digestibility coefficient of neutral detergent fiber decreased linearly as Tifton 85 replacement for Cratylia level was increased, which probably happened due to the presence of highly lignified material within the Cratylia hay. However, the alternative legume maintained animal performance of Tifton 85. In conclusion, Cratylia hay can be recommended as a potential substitute for Tifton 85 hay, which requires greater inputs for the production. Cratylia may be considered a feeding strategy for livestock production, especially for smallholder livestock systems and regions with unfavorable soil and climate. [ABSTRACT FROM AUTHOR]

Corn shredlage is a whole-plant corn silage with a greater proportion of long particles and intensively processed stalks (by shredding and peeling) and kernels (by thorough crushing). Corn shredlage may improve rumen function and milk performance of dairy cows, especially in low-fibre diets. Paradoxically, little is known about the specific effects of corn shredlage on rumen fermentation. This study aimed to understand how the dietary replacement of corn silage with corn shredlage changes feed intake, rumen fermentation, rumination time, and milk performance of dairy cows fed a low-fibre diet. Thirty-four lactating cows were allocated to two dietary treatments in a crossover design with two 30-day periods. The dietary treatment was a total mixed ration with either 1) 25% conventionally processed corn silage (CON; 14-mm theoretical length of cut, TLOC) or 2) 25% corn shredlage (SHR; 26-mm TLOC). Cows on the SHR diet had increased DMI and body weight. Although milk yield was unaffected by diet, cows on the SHR diet tended to have increased yields of 4% FCM, ECM, and milk fat. The yields of milk protein and lactose were not affected by diet. Similarly, the proportion of milk components remained unaffected. The feed efficiency (milk/DMI) was higher in cows fed the CON diet, whereas it remained unaffected when expressed as ECM/DMI. Neither rumination nor rumen fermentation parameters were affected by the diet. Overall, the positive effects of corn shredlage on milk performance were relatively small and a result of increased DMI rather than improved rumen fermentation or rumination. Corn shredlage increased DMI Corn shredlage tended to increase yields of 4% FCM, ECM, and milk fat Corn shredlage did not affect rumination and rumen fermentation [ABSTRACT FROM AUTHOR]

Inclusion of urea in dairy cattle diets is often limited by negative effects of high levels of feed urea on dry matter intake (DMI) and efficiency of rumen N utilization. We hypothesized that supplying urea postruminally would mitigate these limitations and allow greater inclusion of urea in dairy cattle diets. Four rumen-fistulated Holstein-Friesian dairy cows (7 ± 2.1 lactations, 110 ± 30.8 d in milk; mean ± standard deviation) were randomly assigned to a 4 × 4 Latin square design to examine DMI, milk production and composition, digestibility, rumen fermentation, N balance, and plasma constituents in response to 4 levels of urea continuously infused into the abomasum (0, 163, 325, and 488 g/d). Urea doses were targeted to linearly increase the crude protein (CP) content of total DMI (diet plus infusion) by 0%, 2%, 4%, and 6% and equated to 0%, 0.7%, 1.4%, and 2.1% of expected DMI, respectively. Each 28-d infusion period consisted of a 7-d dose step-up period, 14 d of adaptation, and a 7-d measurement period. The diet was fed ad libitum as a total mixed ration [10.9% CP, 42.5% corn silage, 3.5% grass hay, 3.5% wheat straw, and 50.5% concentrate (dry matter basis)] and was formulated to meet 100%, 82%, and 53% of net energy, metabolizable protein, and rumen-degradable protein requirements, respectively. Linear, quadratic, and cubic effects of urea dose were assessed using polynomial regression assuming the fixed effect of treatment and random effects of period and cow. Dry matter intake and energy-corrected milk yield responded quadratically to urea dose, and milk urea content increased linearly with increasing urea dose. Apparent total-tract digestibility of CP increased linearly with increasing urea dose and ruminal NH 3 -N concentration responded quadratically to urea dose. Mean total VFA concentration was not affected by urea dose. The proportion of N intake excreted in feces decreased linearly and that excreted in urine increased linearly in response to increasing urea dose. The proportion of N intake excreted in milk increased linearly with increasing urea dose. Urinary urea excretion increased linearly with increasing urea dose. Microbial N flow responded cubically to urea dose, but the efficiency of microbial protein synthesis was not affected. Plasma urea concentration increased linearly with increasing urea dose. Regression analysis estimated that when supplemented on top of a low-CP diet, 179 g/d of postruminal urea would maximize DMI at 23.4 kg/d, corresponding to a dietary urea inclusion level of 0.8% of DMI, which is in line with the current recommendations for urea inclusion in dairy cattle diets. Overall, these results indicate that postruminal delivery of urea does not mitigate DMI depression as urea dose increases. [ABSTRACT FROM AUTHOR]

This study was aimed to assess the effects of reducing free water access time and feeding milk at various dry matter (DM) concentrations on water consumption, growth performance, DM intake (DMI), and blood metabolites of Holstein dairy calves. Sixty Holstein dairy calves [42 ± 3.0 kg of body weight (BW)] were used in a 3 × 2 factorial randomized block design with the main factors including milk DM (low, medium, and high DM; LDM, MDM, and HDM, 125, 140, and 155 g/kg, respectively) and water access time (short and long-time free water access, ST and LT respectively). Neither milk DM concentration nor water access time had any effect on the mean water intake (L/d). Increasing the concentration of liquid feed in both water provision schedules, improved the final BW, average daily gain (ADG), heart girth, and withers and hip heights. However, main blood metabolites were not affected by milk DM. The LT calves that consumed the highest milk DM (HDM) had the greatest ADG compared to other treatments (P<0.05). A trend was found for the interaction between milk DM and water access time as in the ST calves, the final BW was greater than LT at 125 and 140 g/kg milk concentrations (P=0.08) but at 155 g/kg milk DM, the highest final BW was found in LT calves. It was concluded that under the environmental condition similar to this study, water provision duration for neonatal calves could be reduced to once a day (just 2 h) however, we do not recommend increasing the DM content of milk by more than 140 g/kg when water is provided freely, 2 h once a day. [ABSTRACT FROM AUTHOR]

Tannins can be utilized to increase rumen undegradable protein (RUP) by their capacity to form complexes with diverse nutrients present in the feed. In that regard, high-performance ruminants demand elevated RUP levels. The objective of this study was to evaluate the effects of incorporating varying levels of tannin into three protein sources (cottonseed, peanut, and soybean meals) on ruminal kinetic parameters, ruminal fermentation, and intestinal digestibility. Thus, three in situ experiments were conducted to investigate the ruminal degradation kinetics, where Fraction A represents the soluble portion, Fraction B relates to the portion potentially degraded in the rumen, and kd denotes the degradation rate of Fraction B, for both dry matter (DM) and crude protein (CP) in the rumen. Additionally, the study assessed dry matter effective degradability (ED), rumen undegradable protein (RUP), and intestinal digestibility (ID). These experiments utilized three cannulated animals for the in situ incubations. Regarding cottonseed meal in terms of DM degradation kinetics, tannin inclusion had a quadratic effect on fraction A (p < 0.01), B (p = 0.10, trend), kd (p = 0.03), and ED (p < 0.01). Fraction A of CP had a cubic effect (p = 0.03), being greater for the control compared with the other treatments. The inclusion of tannin linearly increased RUP (p < 0.01). The RUP proportion increased 29, 33, and 45% when 20, 40, and 60 g/kg tannin were used, respectively, compared to the control. For peanut meal, the A fraction of protein and RUP responded quadratically as tannin was included in peanut meal (p < 0.01). However, tannin levels did not affect fraction B of protein and ID. Regarding soybean meal, fractions A and B of DM and ED had cubic effects (p < 0.01), being greater for the control compared with the other treatments, and responded quadratically as tannin increased. Also, tannin inclusion had a cubic effect on fractions A and B of protein, RUP, and ID (p < 0.01). The cubic behavior showed greater B fraction and ID and lower A fraction and RUP for the control compared other treatments (p < 0.01). Tannins offer a promising avenue for elevating RUP levels in diets featuring cottonseed and peanut meals. Nevertheless, no advantages were observed when treating soybean meal with tannin. [ABSTRACT FROM AUTHOR]

The present study was conducted to assess if Dicalcium Phosphate 18% (DCP) supplementation in dairy feed would affect dry matter intake, milk composition, blood mineral balance and milk production in lactating crossbred Dairy Cows). A 4 × 4 double change-over design set as Latin Squares was used to do feeding and digestibility trials. DCP was supplemented at different levels 0; 0.3; 0.6; 0.9% DM/day of DCP for which the experimental groups was respectively designated as T0, T1, T2, T3, The effect of DCP supplementation on parameters of interest was evaluated using blood serum, milk, feed and feed refusals samples. The present study revealed that supplementation of DCP with the concentrate mix improved mean dry matter intake (11.46; 12.81; 14.59, and 15.68 kg DM/d) for T0, T1, T2, T3, respectively, and digestibility of nutrients in lactating dairy cows compared to the controls. Likewise, DCP supplementation improved milk production and composition except solids not fat (SNF) composition. Serum calcium (Ca) composition was significantly in supplemented group (p<0.05). DCP supplementation significantly improved (p<0.05) total Ca intake, Ca in milk, Ca in feces, total Ca excretion. Optimum dairy cow production and productivity was achieved at 0.6% DM/day of DCP supplementation. However, the current results need to be confirmed using large number of lactating dairy animals. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of high concentrate diets (HCD) on the rumen fermentation and the digestibility of nutrients in different sites of the gastrointestinal tract (GIT) in goats. Four goats were used in a crossover design. The goats were fitted with a ruminal cannula and flexible T-cannulae proximal duodenum and terminal ileum. Treatments were as follows: low concentrate group (LCG) and high concentrate group (HCG). Duodenal flow and forestomach digestibility of starch were significantly higher in the HCG than those in the LCG (p < 0.05); There was no significant difference in ileum flow and digestibility of starch in the small intestine, large intestine and total GIT (p > 0.05). The digestibility of crude protein (CP) in the forestomach was significantly higher in the HCG than in the LCG (p < 0.05); the flow of the duodenum and ileum of CP, and the CP digestibility of the small intestine, large intestine and total GIT were not significantly different between groups (p > 0.05). The duodenal and ileal flow of neutral detergent fiber (NDF), the NDF digestibility of the different segments and total GIT were not significantly different between groups (p > 0.05). Compared to the LCG, the ruminal pH of the HCG was significantly lower (p < 0.05). The HCG concentrations of microbial crude protein, ammonia nitrogen and isovaleric acid were significantly higher (p < 0.05) than the LCG. The foam strength, foam production and viscosity of the rumen fluid in the HCG were higher than the LCG (p < 0.01). These results showed that when the goats were fed with HCD, the digestibility of nutrients was not significantly impaired, but the risk of frothy rumen bloat increased. Due to a serious shortage of high-quality roughage in China, producers commonly used a high-concentrate diet in ruminants, which can improve animal production performance. Gastrointestinal digestive function plays a vital role in the absorption of nutrients and the healthy growth of animals. Therefore, this research evaluated the digestibility of various nutrients in different segments of the gastrointestinal tract (GIT) under HCD feeding by using three-site cannula goats as experimental animals. The results indicated that the GIT of goats could fully digest nutrients such as starch and protein under HCD feeding conditions. [ABSTRACT FROM AUTHOR]

Allowing dairy cattle to access pasture or outdoor areas is known to be beneficial for cows' welfare and is considered important by the general public. However, in confinement-based operations with high-yielding cows, pasture access may be difficult to implement, especially for lactating animals. Providing pasture access to heifers and dry cows seems a more feasible option for most farms. The objective of this study was to investigate the effects of providing high-yielding dairy cows with free-choice pasture access during the dry period on their health, behavior, and milk production. Over the study period, a total of 78 Holstein cows were assigned to 1 of 2 treatments during the dry period (51 ± 8 d): housing with free-choice access to the pasture (PAST) or housing continuously without any access to the outdoors (CTRL). After calving, all cows from both treatments were mixed and housed continuously. To assess the effects of the treatment on cows' performance, all animals enrolled were monitored both before calving and during the first 100 d in milk of the following lactation. The behavior of all cows involved was monitored continuously during the whole observation period using collar-based sensors. All cows were inspected monthly to assess lameness, hock lesions, cleanliness, and body condition score. During the period after calving (0–100 d in milk), milk production and composition were also monitored. Results showed that free-choice pasture access affected cows' feeding behavior. Before calving, the animals in PAST spent more time feeding than in CTRL and, interestingly, this difference tended to persist for several weeks after calving. During the dry period, cows in PAST were cleaner than in CTRL but no differences in locomotion and body condition score were found between the 2 groups. Free-choice pasture access during the dry period also affected milk production during the following lactation. The cows that spent the dry period in PAST produced more milk than CTRL counterparts, particularly for the animals that calved during summer. In the current study we have found that providing free-choice pasture access during the dry period can positively affect the performance of dairy cattle and represents a desirable practice in confinement-based dairy production systems. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the effects of post-ruminal supply of urea (PRU) on nutritional status, and liver metabolism of pregnant beef cows during late gestation. Twenty-four Brahman dams, pregnant from a single sire, and weighing 545 kg ± 23 kg were confined into individual pens at 174 ± 23 d of gestation, and randomly assigned into one of two dietary treatments up to 270 d of gestation: Control (CON, n = 12), consisting of a basal diet supplemented with conventional urea, where the cows were fed with diets containing 13.5 g conventional urea per kg dry matter; and PRU (PRU, n = 12), consisting of a basal diet supplemented with a urea coated to extensively prevent ruminal degradation while being intestinally digestible, where the cows were fed with diets containing 14,8 g urea protected from ruminal degradation per kg dry matter. Post-ruminal supply of urea reduced the urine levels of 3-methylhistidine (P = 0.02). There were no differences between treatments for dry matter intake (DMI; P = 0.76), total digestible nutrient (TDN) intake (P = 0.30), and in the body composition variables, such as, subcutaneous fat thickness (SFT; P = 0.72), and rib eye area (REA; P = 0.85). In addition, there were no differences between treatments for serum levels of glucose (P = 0.87), and serum levels of glucogenic (P = 0.28), ketogenic (P = 0.72), glucogenic, and ketogenic (P = 0.45) amino acids, neither for urea in urine (P = 0.51) as well as urea serum (P = 0.30). One the other hand, enriched pathways were differentiated related to carbohydrate digestion, and absorption, glycolysis, pyruvate metabolism, oxidative phosphorylation, pentose phosphate pathway, and biosynthesis of amino acids of the exclusively expressed proteins in PRU cows. Shifting urea supply from the rumen to post-ruminal compartments decreases muscle catabolism in cows during late gestation. Our findings indicate that post-ruminal urea supplementation for beef cows at late gestation may improve the energy metabolism to support maternal demands. In addition, the post-ruminal urea release seems to be able to trigger pathways to counterbalance the oxidative stress associated to the increase liver metabolic rate. [ABSTRACT FROM AUTHOR]

Objectives were to determine the effects of supplementing increasing amounts of choline ion on hepatic composition and mRNA abundance in pregnant dry cows subjected to a fatty liver induction protocol. Holstein cows (35 primiparous and 41 multiparous) at mean (± standard deviation) of 211 ± 9.9 days of gestation were blocked by body condition (3.59 ± 0.33) and assigned to receive 0, 6.45, 12.90, 19.35, and 25.80 g/day of choline ion as rumen-protected choline (RPC) as a top-dress for 14 days. Cows were fed for ad libitum intake on days 1 to 5 and restricted to 30% of the required net energy for lactation from days 6 to 14 of the experiment. Hepatic tissue was sampled on days 5 and 14 and analyzed for concentrations of triacylglycerol and glycogen, and mRNA abundance was investigated. Orthogonal contrasts evaluated the effects of supplementing RPC (0 g/day vs. rest), and the linear, quadratic, and cubic effects of increasing intake of choline ion from 6.45 to 25.80 g/day. Results are depicted in sequence of treatments from 0 to 25.8. During feed restriction, RPC reduced the concentration of hepatic triacylglycerol by 28.5% and increased that of glycogen by 26.1%, and the effect of increasing RPC intake on triacylglycerol was linear (6.67 vs. 5.45 vs. 4.68 vs. 5.13 vs. 3.81 ± 0.92% wet-basis). Feeding RPC during feed restriction increased abundance of transcripts involved in choline metabolism (CHKA, PLD1), synthesis of apolipoprotein-B100 (APOB100), and antioxidant activity (GPX3), and decreased the abundance of transcripts involved in hepatic lipogenesis (DGAT2, SREBF1) and acute phase response (SAA3). Most effects were linear with amount of choline fed. Changes in hepatic mRNA abundance followed a pattern of reduced lipogenesis and enhanced lipids export, which help explain the reduced hepatic triacylglycerol content in cows fed RPC. Choline exerts lipotropic effects in dairy cows by altering transcript pathways linked to hepatic lipids metabolism. [ABSTRACT FROM AUTHOR]

Context. Mitigating urinary nitrogen (N) losses is an important target of sustainable cattle nutrition concepts. One option to achieve this may be dietary inclusion of tanniferous herbs. Aims. Aim of the study was to investigate herbs with different profiles of tannins for their efficiency to abate urinary N losses. Small burnet (Sanguisorba minor) with high concentrations of total tannins, plantain (Plantago lanceolata) with low concentrations and birdsfoot trefoil (Lotus corniculatus) with expectedly high concentrations of condensed tannins were included in the treatments. Methods. The test plants were mixed in dried form into a grass-maize-silage diet at 80 g/kg of dietary dry matter. They replaced dried perennial ryegrass (control). Twenty-four multiparous dairy cows were randomly allocated to the four diets. Intake, eating time, rumination time, and milk yield were recorded individually, and representative samples of milk and excreta were collected and analysed six times within 14 days, following 10 days of adaptation. The diets with ryegrass, birdsfoot trefoil, plantain or burnet contained, per kilogram of dry matter, 0, 1.8, 1.2 and 1.9 g condensed tannins, 0.1, 1.9, 1.7 and 15.5 g total tannins, and 26.2, 28.5, 27.5 and 26.6 g N. Key results. Milk yield and composition were not affected by treatment, apart from a decline in milk protein content when feeding plantain. Milk urea concentration was reduced with burnet by more than 30%, compared with the control and plantain. Birdsfoot trefoil also reduced milk urea concentration, but to a lesser degree. Furthermore, the burnet treatment substantially shifted N excretion from urine to faeces (about 30% lower urine N losses). All treatments lowered the proportion of fine particles of <1.0 mm in faeces, what might be due to high fibre content of the control. Conclusions. At dietary proportion of 80 g/kg, burnet is a forage herb with potential to reduce ruminal ammonia generation as indicated by reduced urinary N and milk urea. Plantain and birdsfoot trefoil had no or negligible effects. Implications. The study indicated that small burnet could have potential as a feed additive for dairy cows in terms of N-use efficiency, lower emissionsto the environment, and reduced animal metabolic stress. [ABSTRACT FROM AUTHOR]

Dry matter intake (DMI, kg/d) is closely related to the magnitude of negative energy and protein balance during the transition period, and the metabolic adaptations to support lactation in dairy cows. Thus, DMI might affect the development of cytological endometritis in the early postpartum period. Difficulty to adapt to these metabolic changes is related to impaired immune function and increased occurrence of reproductive disorders. We aimed to examine the association of pre- and postpartum DMI, body weight (BW), body condition score, milk yield and milk composition, and days to first ovulation with cytological endometritis at 15 (CYT15) and 30 DIM (CYT30). A second objective was to understand the association of vaginal discharge with CYT15 and CYT30 and performance. We conducted a pooled statistical analysis of 5 studies, including data from 280 multiparous Holstein cows. Based on the cutoffs for the percentage of uterine polymorphonuclear cells (PMN), determined by taking the median value of the data set for 15 and 30 DIM, cows were categorized as follows: LOW15 (PMN % at 15 DIM ≤24%; n = 125), HIGH15 (PMN % at 15 DIM >24%; n = 125), LOW30 (PMN % at 30DIM ≤7%; n = 141); and HIGH30 (PMN % at 30DIM >7%; n = 139). Cows in HIGH15 consumed an average of 1.97 ± 0.5 kg/d less DM than cows in LOW15 during prepartum, and 3.01 ± 0.5 kg/d less DM during postpartum. Dry matter intake (as a percentage of BW) was higher for cows in LOW15 during pre- and postpartum than for cows in HIGH15. Moreover, cows in HIGH15 tended to have lower milk yield than cows in LOW15 from the third until the fifth week postpartum. Although DMI was not associated with CYT30, DMI (as a percentage of BW) was lower for cows in LOW30 pre- and postpartum than for cows in HIGH30. There was no association between CYT30 and milk yield. Cows in LOW15 had greater days to first ovulation than cows in HIGH15, while cows in LOW30 also had greater days to first ovulation than cows in HIGH30. Simple regression analyses demonstrated linear associations of increased DMI, particularly postpartum, with decreased uterine PMN percentage and lower vaginal discharge score. Additionally, increased units of vaginal discharge score and increased percentage units of uterine PMN were linearly associated with decreased milk yield. Corroborating with the notion of the ovarian function being associated with uterine inflammatory status, cows in HIGH15 and HIGH30 ovulated on average 3 d before than cows in LOW15 and LOW30, respectively. Cytological endometritis at 15 DIM was associated with lower DMI from 4 wk before calving until 4 wk postpartum and was associated with lower milk yield. The association of vaginal discharge with cytological endometritis was variable and dependent on the day of evaluation. [Display omitted] [ABSTRACT FROM AUTHOR]

Gangue-based backfill cementitious materials (BCM) are widely applied due to their low CO2 footprint, while the application is restricted by gangue's low reactivity. In this study, dry chemical modification was developed to modify the gangue, and multiple characterized approaches were used to characterize the dissolution property, mineral composition, and particle size distribution of modified gangue (MCG), as well as the compressive strength and microstructure of BCM. The findings show that the residue weight of MCG stabilized at 2 wt.% of formic acid, and the modification reduces the kaolinite and calcite, resulting in smaller particles. Additionally, the three days compressive strength of the BCM made with MCG was improved from 0.3 MPa to 0.6 MPa. Attributed to the increased reactivity of MCG, it was found that the dissolution weight increased by 2.13%. This study offers a novel method for activating gangue and a new kind of MCG-prepared BCM, which makes a significant contribution towards achieving the UN Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

The study was conducted to determine the proximate composition, dry matter degradability in the rumen and the cost of each feed ingredient used in the formulation. The feed ingredients used in formulating the rations were; watermelon peel, orange peel, groundnut haulms and poultry litter. The dry matter proximate composition ranged from 88 to 92% (F6 to F4). Crude protein was shown to be lowest in F2 (10.0%) and highest in F5 (20.18%) which was probably due to higher proportion of orange peel. Crude fibre recorded in F2 (25.21%) was the highest while F6 (4.0%) was the lowest. Ether extract ranges from 3.9% (F6) to 2.0%(F5). This was probably due to the orange peel content of the ration. The degradation observed ranged from 6.80% to 39.95% at 3 hours, 23.60 to 38.00% at 6 hours and a slight increase (35.15 to 38%) was noticed at 12 hours. It ranged from 35.15% to 52.70%, at 24 hours, 42.20% to 64.80%, at 48 hours and 56.40% to 73.44% at 72 hours. The cost of the formulation recorded showed F4 (N 450) to be the lowest and F3 (N 1250) highest. The outcome of the study showed that F5 and F6 had higher degradability, and crude protein, and moderate cost. [ABSTRACT FROM AUTHOR]

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Simple Summary: Climate change and environmental heat stress are important challenges for the future of the dairy industry, as these environmental factors can reduce the productive and reproductive performance of dairy cows. Therefore, relieving the heat stress of dairy cows is an important priority for the dairy industry. Plant extracts have advantages in safety, efficiency, low toxic side effects (if correctly selected) and residue, thus, can significantly aid in alleviating heat stress in dairy cows. This paper reviews the effects of some plant extracts on alleviating heat stress in dairy cows and their possible regulatory mechanisms. The aim is to develop applicable strategies using plant extracts to alleviate heat stress in dairy cows. Heat stress (HS) in cows is a critical issue in the dairy industry. Dairy cows accumulate heat from body metabolism, along with that imposed by air temperature, humidity, air flow and solar radiation. HS in animals can occur during hot and humid summers when the ambient temperature is extremely high. Dairy cows have relatively high feed intakes and metabolic heat production and are thus susceptible to HS, leading to reductions in feed intake, lower milk yield, affected milk quality, reduced animal health and even shortening the productive lifespan of cows. Therefore, alleviating HS is a top priority for the dairy industry. Suitable plant extracts have advantages in safety, efficiency and few toxic side effects or residues for applications to alleviate HS in dairy cows. This paper reviews the effects of some plant extract products on alleviating HS in dairy cows and briefly discusses their possible mechanisms of action. [ABSTRACT FROM AUTHOR]

Knowledge about individual daily herbage dry matter (DM) intake (DMI) helps identifying efficient dairy cows and adapting supplementation better to herbage intake and nutrient requirements of grazing dairy cows. With the aid of behavioural characteristics, raw data recorded with the RumiWatch (RW) system and processed with the RW converter 0.7.3.31 (C31), estimation of herbage DMI may be possible. First, C31, which allows differentiation of prehension bites and mastication chews, was validated through direct observation of behavioural characteristics and compared to the previous RW converter 0.7.3.11 (C11). Further, the influence of a low and high pre‐grazing herbage mass (HM), with the same target herbage allowance (HA), on bite mass, DMI, number of prehension bites, and milk production was investigated. In total, 24 lactating Holstein cows were pairwise allotted to one of two HM treatments. The cows received a new pasture paddock twice per day with a daily target HA of 22 kg DM per cow/day. On average, low HM (LHM) and high HM (HHM) paddocks had an HM of 589 and 2288 kg DM/ha, respectively, above 6.7 click units (1 CU = 0.5 cm). Overall, LHM cows produced 2.7 kg/day more milk and 2.5 kg/day more energy‐corrected milk, had the same herbage DMI and a similar prehension bite mass. The averaged bite mass per week was 0.49 g DM/bite (LHM) or 0.47 g DM/bite (HHM), respectively. A longer eating time (617 vs. 559 min/day) and a shorter rumination time (297 vs. 365 min/day) were observed for the LHM cows compared with the HHM cows. The validation of the RW showed similar results for C11 and C31 apart from prehension bites, where C31 showed a mean absolute deviation of 12.4%. Pre‐grazing HM had no effect on relevant behavioural characteristics for prospective intake estimation, namely, bite mass and number of prehension bites. [ABSTRACT FROM AUTHOR]

Fusarium mycotoxins are inactivated by rumen flora; however, a certain amount can pass the rumen and reticulum or be converted into biological active metabolites. Limited scientific evidence is available on the impact and mitigation of Fusarium mycotoxins on dairy cows' performance and health, particularly when cows are exposed for an extended period (more than 2 months). The available information related to these mycotoxin effects on milk cheese-making parameters is also very poor. The objective of this study was to evaluate a commercially available mycotoxin mitigation product (MMP, i.e., TOXO® HP-R, Selko, Tilburg, The Netherlands) in lactating dairy cows fed a Fusarium mycotoxin-contaminated diet, and the repercussions on the dry matter intake, milk yield, milk quality, cheese-making traits and health status of cows. The MMP contains smectite clays, yeast cell walls and antioxidants. In the study, 36 lactating Holstein cows were grouped based on the number of days of producing milk, milk yield, body condition score and those randomly assigned to specific treatments. The study ran over 2 periods (March/May–May/July 2022). In each period, six animals/treatment were considered. The experimental periods consisted of 9 days of adaptation and 54 days of exposure. The physical activity, rumination time, daily milk production and milk quality were measured. The cows were fed once daily with the same total mixed ration (TMR) composition. The experimental groups consisted of a control (CTR) diet, with a TMR with low contamination, high moisture corn (HMC), and beet pulp; a mycotoxins (MTX) diet, with a TMR with highly contaminated HMC, and beet pulp; and an MTX diet supplemented with 100 g/cow/day of the mycotoxin mitigation product (MMP). The trial has shown that the use of MMP reduced the mycotoxin's negative effects on the milk yield and quality (protein, casein and lactose). The MTX diet had a lower milk yield and feed efficiency than the CTR and MMP HP-R diets. The MMP limited the negative effect of mycotoxin contamination on clotting parameters, mitigating the variations on some coagulation properties; however, the MMP inclusion tended to decrease the protein and apparent starch digestibility of the diet. These results provide a better understanding of mycotoxin risk on dairy cows' performances and milk quality. The inclusion of an MMP product mitigated some negative effects of the Fusarium mycotoxin contamination during this trial. The major effects were on the milk yield and quality in both the experimental periods. These results provide better insight on the effects of mycotoxins on the performance and quality of milk, as well as the cheese-making traits. Further analyses should be carried out to evaluate MMP's outcome on immune–metabolic responses and diet digestibility. [ABSTRACT FROM AUTHOR]

This article aims to review recent progress and update on utilization of exogenous fibrolytic enzymes in fiber fermentation, degradation, and digestions and nutritive and anti-nutritional characteristics of whole legume faba bean and its silage. The study focused on strategies to improve the utilization and bioavailability of fiber through pre-treating exogenous fibrolytic enzymes. The review includes features of nutrition and anti-nutritional factors and environment impact, forage fiber fermentation, degradation and digestion, legume bean in various diets, use of exogenous enzyme and factor affecting enzyme action in fiber digestion as well as exogenous enzyme response. This review also provides very recent research on effects of fibrolytic enzyme on rumen degradation characteristics of dry matter and fiber of whole plant faba bean silage and effect of exogenous fibrolytic enzyme derived from trichoderma reesei on lactational performance, feeding behavior, rumen fermentation and nutrient digestibility in dairy cows fed whole plant faba bean silage-based diet. This study provides an insight on nutritive and anti-nutritive characteristics of whole legume bean and its plant silage and utilization of exogenous fibrolytic enzymes in fiber fermentation, degradation, and digestions. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to determine the effect of dietary supplementation of n-3 polyunsaturated fatty acids (PUFA) and n-6 PUFA on dry matter intake (DMI), energy balance, oxidative stress, and performance of transition cows. Forty-five multiparous Holstein dairy cows with similar parity, body weight (BW), body condition score (BCS), and milk yield were used in a completely randomized design during a 56-d experimental period including 28 d prepartum and 28 d postpartum. At 240 d of pregnancy, cows were randomly assigned to one of the 3 isoenergetic and isoprotein dietary treatments, including a control ration containing 1% hydrogenated fatty acid (CON), a ration with 8% extruded soybean (HN6, high n-6 PUFA source), and a ration with 3.5% extruded flaxseed (HN3; high n-3 PUFA source). The HN6 and HN3 diets had an n-6/n-3 ratio of 3.05:1 and 0.64:1 in prepartum cows and 8.16:1 and 1.59:1 in postpartum cows, respectively. During the prepartum period (3, 2, and 1 wk before calving), DMI, DMI per unit of BW, total net energy intake, and net energy balance were higher in the HN3 than in the CON and NH6 groups. During the postpartum period (2, 3, and 4 wk after calving), cows fed HN3 and HN6 diets both showed increasing DMI, DMI as a percentage of BW, and total net energy intake compared with those fed the CON diet. The BW of calves in the HN3 group was 12.91% higher than those in the CON group. Yield and nutrient composition of colostrum (first milking after calving) were not affected by HN6 or HN3 but milk yield from 1 to 4 wk of milking was significantly improved compared with CON. During the transition period, BW, BCS, and BCS changes were not affected. Cows fed the HN6 diet had a higher plasma NEFA concentration compared with the CON cows during the prepartum period. Feeding HN3 reduced the proportion of de novo fatty acids and increased the proportion of preformed long-chain fatty acids in regular milk. In addition, the n-3 PUFA-enriched diet reduced the n-6/n-3 PUFA ratio in milk. In conclusion, increasing the n-3 fatty acids concentration in the diet increased both DMI during the transition period and milk production after calving, and supplementing n-3 fatty acids was more effective in mitigating the net energy balance after calving. [ABSTRACT FROM AUTHOR]

Background and Aim: Improving the feed efficiency of beef cattle is necessary to increase the profitability of meat production. Implementing marker-assisted selection breeding systems can improve the genetic potential of beef cattle for increased productivity. This research aimed to study the effects of insulin-like growth factor (IGF)-1 C472T, growth hormone (GH) C2141G, and GH receptor (GHR) T914A polymorphisms on growth performance and feed efficiency in young Kazakh white-headed cattle. Materials and Methods: Young Kazakh white-headed cattle (n = 50) were grouped after weaning according to sex (28 bulls and 22 heifers) and they were genotyped according to the IGF-1 C472T, GH C2141G, and GHR T914A polymorphisms. The test period was conducted from 8 to 15 months of age. The experimental animals were evaluated for live weight (LW) at the beginning and end of the test period. They were also assessed for average daily gain, hip height, metabolic mid-weight (MMWT), actual dry matter intake (DMI), and residual feed intake (RFI). Results: Significant differences in MMWT were found between the bulls with the IGF-1TT and IGF-1CT genotypes, which was a 2.2 kg increase in heterozygous cattle (p < 0.05). Heterozygous IGF-1CT bulls differed with a higher DMI of 0.087 kg/ day (p < 0.05) compared to IGF-1TT homozygotes. Carriers of the IGF-1TT genotype had the greatest feed efficiency at 0.068 kg/day (p < 0.05). Heifers with the GHCC genotype differed in their maximum DMI with an increase of 1.17%–1.57% (p < 0.05) relative to the other genotypes. The G allele in the GH C2141G polymorphism was associated with better (p < 0.05) feed efficiency in the Kazakh white-headed breed. The minimum DMI and RFI in GHR T914A heterozygous heifers were significantly inferior (p < 0.05) to the other genotypes. Conclusion: Association studies of the IGF-1 C472T, GH C2141G, and GHR T914A polymorphisms indicate a relationship between growth, development, and feed efficiency with the genetic characteristics of young Kazakh white-headed cattle. A significant (p < 0.05) dominant effect was found in the IGF-1 gene in bulls and in the GHR gene in heifers, which should be considered when breeding with heterogeneous parental pairs. The negative effect of the allele substitution in the IGF-1 C472T polymorphism was observed in the LW of heifers (−3.25 kg) at the age of 8 months and bulls (−6.05 kg) at 15 months. The substitution in the GH C2141G polymorphism was associated with a significant reduction in DMI by 0.036 kg (p < 0.05) and an increase in feed efficiency by 0.023 kg (p < 0.05) during the rearing of heifers. These results can improve the production efficiency of mature herds of Kazakh white-headed cattle. [ABSTRACT FROM AUTHOR]

This study examined the impact of two corn processing methods (steam-flaked (SFC) vs. ground) combined with two weaning ages (50 or 75 days) on calf performance, blood metabolites, rumen fermentation, nutrient digestion, and behavior. The study involved 48 three-day-old Holstein calves, with an average body weight of 41.4 ± 2.2 kg. The experimental design was a 2 × 2 factorial arrangement, resulting in four treatment groups: SFC50 (SFC and weaning at 50 days), SFC75 (SFC and weaning at 75 days), GC50 (ground corn and weaning at 50 days), and GC75 (ground corn and weaning at 75 days). Calves were given whole milk at 4 L/ day from day 3–15 and 7 L/ day from day 16 to either 43 or 68, depending on weaning age. Weaning occurred between days 44 and 50 for early-weaned calves and between days 69 and 75 for late-weaned calves. The study lasted until calves were 93 days old. The starter ration consisted of soybean meal, corn grain, 5% chopped wheat straw and premix. Results indicated that the SFC-based starter feed improved calf performance and nutrient digestion, as evidenced by increased weight gain, dry matter, crude protein, and neutral detergent fiber digestibility. Calves fed the SFC-based starter diet had lower blood albumin and urea N concentrations, while blood total protein and globulin concentrations were higher, especially in early-weaned calves. No significant changes in rumen pH and ammonia-N concentration were observed. In addition, the SFC starter feed resulted in higher volatile fatty acids concentration and longer feeding time in weaned calves compared to ground corn. Overall, these results suggest that an SFC-based starter feed may be beneficial for both early and late weaned calves. [ABSTRACT FROM AUTHOR]

The extent to which a nutrition-related disorder such as ketosis alters the ruminal microbiota or whether microbiota composition is related to ketosis and potential associations with host metabolism is unknown. We aimed to evaluate variations occurring in the ruminal microbiota of ketotic and nonketotic cows in the early postpartum period, and how those changes may affect the risk of developing the disease. Data on milk yield, dry matter intake (DMI), body condition score, and blood β-hydroxybutyrate (BHB) concentrations at 21 d postpartum were used to select 27 cows, which were assigned (n = 9 per group) to a clinical ketotic (CK, 4.10 ± 0.72 mmol BHB/L, DMI 11.61 ± 0.49 kg/d, ruminal pH 7.55 ± 0.07), subclinical ketotic (SK, 1.36 ± 0.12 mmol BHB/L, DMI 15.24 ± 0.34 kg/d, ruminal pH 7.58 ± 0.08), or control (NK, 0.88 ± 0.14 mmol BHB/L, DMI 16.74 ± 0.67/d, ruminal pH 7.61 ± 0.03) group. Cows averaged 3.6 ± 0.5 lactations and a body condition score of 3.11 ± 0.34 at the time of sampling. After blood serum collection for metabolomics analysis (1H nuclear magnetic resonance spectra), 150 mL of ruminal digesta was collected from each cow using an esophageal tube, paired-end (2 × 300 bp) sequencing of isolated DNA from ruminal digesta was performed via Illumina MiSeq, and sequencing data were analyzed using QIIME2 (v 2020.6) to measure the ruminal microbiota composition and relative abundance. Spearman correlation coefficients were used to evaluate relationships between relative abundance of bacterial genera and concentrations of serum metabolites. There were more than 200 genera, with approximately 30 being significant between NK and CK cows. Succinivibrionaceae UCG 1 taxa decreased in CK compared with NK cows. Christensenellaceae (Spearman correlation coefficient = 0.6), Ruminococcaceae (Spearman correlation coefficient = 0.6), Lachnospiraceae (Spearman correlation coefficient = 0.5), and Prevotellaceae (Spearman correlation coefficient = 0.6) genera were more abundant in the CK group and were highly positively correlated with plasma BHB. Metagenomic analysis indicated a high abundance of predicted functions related to metabolism (37.7%), genetic information processing (33.4%), and Brite hierarchies (16.3%) in the CK group. The 2 most important metabolic pathways for butyrate and propionate production were enriched in CK cows, suggesting increased production of acetyl coenzyme A and butyrate and decreased production of propionate. Overall, the combined data suggested that microbial populations may be related to ketosis by affecting short-chain fatty acid metabolism and BHB accumulation even in cows with adequate feed intake in the early postpartum period. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the fecal excretion of N (TN and NH4 +-N) in dairy cows receiving the feed supplement Biolife® (Eurovix S.p.A., Italy) containing active dry yeast Saccharomyces cerevisiae. Two groups of 14 Holstein cows (B – experimental; C – control) at tie-stalled breeding participated in the experiment. Group B received the feed supplement through the total mixed ration (TMR). Fresh feces samples from both groups were collected on d 7, 14, 21, 28, 35 from the start of supplementation. Mean values of fecal pH and excreted DM did not differ between groups. The concentration of NH4 +-N in the fecal samples of group B was reduced by 28.05%, average for the entire studied period (P<0.05). In the period d 21-35, this reduction was 35% (P=0.095). Excreted TN, averaged over the entire period, was reduced by 16.18% in group B, but the difference was not statistically significant. The reduction of TN content in feces from group B was more pronounced in the period d 21-35, when the reduction was 31.99% compared to group C (P=0.084). A period of at least 14 days is required for adaptation to the supplement and for an occur effect on N excretion. [ABSTRACT FROM AUTHOR]

This study aimed to create an equation to predict dry matter intake (DMI) and milk production and N-ureic in the milk of dairy cows managed in tropical conditions in Brazil. We used 113 observations from three experiments using lactating Jersey, Girolando, and Holstein cows. The goodness of fit of the developed equations was evaluated using the coefficients of determination (r2) and root mean square error (RMSE). There was a positive correlation between body weight and milk yield (MY) of r = 0.73. The equation considered DMI to be the most important variable to estimate the MY (r2 = 0.65). Four equations were adjusted to estimate the DMI, where, by a stepwise procedure, the first variable included in the equation was the neutral detergent fibre intake, which explained 92% of the DMI of the cows. However, when the variables BW, MY, and milk fat were included in the equation, there was a reduction of 0.06 in RMSE and an increase in precision (r2 = 0.94). The nutrient intake, milk production, and characteristics prediction equations present satisfactory precision and accuracy for dairy cows managed in tropical conditions in Brazil. [ABSTRACT FROM AUTHOR]

The objective of present study was to assess the effects of unprotected and calcium salts of oils on total tract digestibility, ruminal degradation and fermentation in lambs. Four lambs fitted with ruminal fistula were used in a change-over design using 2 × 2 factorial arrangement. Levels of first factor (oils) were palm oil and linseed oil and levels of second factor were protected oil (calcium salts) and unprotected oil. Feeding of palm oil resulted in higher ruminal effective degradability of neutral detergent fiber (NDF) than linseed oil, and lambs fed protected oil had higher ruminal effective degradability of NDF than unprotected oil (P<0.05). Lambs fed palm oil had higher dry matter intake (DMI) and total tract digestibility of nutrients compared to those fed linseed oil. Acetate concentration in lambs fed palm oil was higher compared to linseed oil. Feeding of protected oil resulted in higher acetate concentration than unprotected oil (P<0.05). The lowest acetate concentration was found in lambs fed unprotected linseed oil (ULO) and the highest acetate concentration was observed in lambs fed unprotected and protected palm oil (UPO and PPO, respectively). Lambs fed palm oil had the highest gas and methane production compared to linseed oil. Protected oil resulted in higher gas and methane production than unprotected oil (P<0.05). Lambs fed PPO had the highest, and those fed ULO had the lowest methane production (P<0.05). Based on the results, protection of linseed oil is necessary to enhance ruminal degradation and fermentation, but this process is not necessary for palm oil. [ABSTRACT FROM AUTHOR]

We aimed to test the associative effects among forages, and between forage and concentrates on the in vitro digestibility of dry matter and neutral detergent fibre using an artificial ruminal fermentation system. The study consisted of two assays, in which associative effects were evaluated among three forages, sugarcane, maize silage, and Tifton 85 hay under two incubation conditions (single feed or all feeds together in a jar), and the associative effects between sugarcane and soybean meal and/or ground maize. For the first assay, sugarcane digestibility increased (p < 0.02), whereas the maize silage digestibility decreased (p < 0.01) when forages were incubated together in the same jar. Tifton hay digestibility was not altered (p ≥ 0.57) by the incubation condition. In the second assay, the sugarcane digestibility was depressed (p < 0.05) when the forage was incubated along with maize grain. For both assays, the pattern of repeatability for digestibility estimates presented an influence of the incubation condition. We concluded that the incubation of different feeds together in the same jar using artificial fermenters causes associative effects among them. These effects can influence the estimates of in vitro dry matter and fibre digestibility and alter their repeatability. [ABSTRACT FROM AUTHOR]

Single-cell ingredients (SCI) are considered promising nutrient sources which are produced using environmentally friendly biotechnological processes. The aim of the current study was to evaluate the replacement of fishmeal, plant protein sources, and fish oil with SCI in organic feeds for European sea bass (Dicentrarchus labrax). Bacterial protein, yeast protein, and microalgae were used to replace fishmeal trimmings, soya bean meal, and fish oil from trimmings. Triplicate groups (30 fish per replicate) of European sea bass (14.4 ± 2.4 g) were fed the experimental diets for 71 days. The results showed that the incorporation of SCI at all levels of inclusion significantly enhanced nutrient digestibility. Additionally, growth performance parameters were not affected by SCI inclusion, exhibiting similar or improved values. Moreover, a tendency for improved anterior and posterior gut structure was observed and a significant increase of lysozyme activity at the two highest inclusion levels of SCI was determined. Overall, the results showed that the inclusion of SCI at 15% (bacterial: yeast: algae—9.4: 4.7: 1) is possible without compromising any of the parameters evaluated. According to these findings, a higher substitution of fishmeal trimmings, plant protein sources, and fish oil from trimmings with SCI in organic diets for European sea bass (D. labrax) can be further evaluated in future studies. [ABSTRACT FROM AUTHOR]

Simple Summary: There is increasing interest in the use of behavioral indicators to identify and even predict health disorders in dairy cattle, allowing for improved management and treatment strategies. The behavior changes such as the prepartum total daily rumination (TDR), total daily activity (TDA) and dry matter intake (DMI) have been suggested as predictors for subclinical hypocalcemia (SCH) and hypomagnesemia (HYM) postpartum. Our main objective was to evaluate the association between rate of change in rumination and activity behavior and DMI across the three days prior to calving with SCH and HYM status at D0 (day of calving) and D3 postpartum. Our results suggest that the rate of change in prepartum TDR, TDA and DMI is not an effective estimator of SCH and HYM status postpartum. Changes in prepartum behaviors such as total daily rumination (TDR), total daily activity (TDA) and dry matter intake (DMI) have the potential to be used as early indicators for cows at risk for subclinical hypocalcemia (SCH) or hypomagnesemia (HYM) after calving. Our objective was to investigate associations between average daily rate of change in total daily rumination (ΔTDR), total daily activity (ΔTDA) and dry matter intake (ΔDMI) from −3 days prepartum to calving with SCH and HYM at D0 or D3 relative to calving. Prepartum TDR, TDA and DMI were measured in 64 Holstein dairy cows. Blood samples were taken at D0 and D3 post-calving for the measurement of total plasma Ca and Mg concentration. Linear regression models were used to analyze the association between ΔTDR, ΔTDA and ΔDMI and SCH and HYM at D0 and D3 relative to calving. Potential confounding variables were offered to the models and backwards selection was used to determine which covariates to retain. No significant differences in prepartum ΔTDR, ΔTDA or ΔDMI were found between cows with or without SCH and HYM at D0 and D3. Our results suggest that the change in TDR, TDA and DMI in the last 3 days prepartum are not effective predictors for cows that will have SCH or HYM in the first 3 days postpartum. [ABSTRACT FROM AUTHOR]