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With the anticipated population growth by 2050, the demand for high-quality protein for human consumption is set to rise. To enhance the sustainability of U.S. cattle production, producers and researchers have traditionally concentrated on improving the feed efficiency of steers through advancements in genetics, nutrition, and microbiome tools, resulting in a more marketable beef product. However, without successful pregnancies, there would be no marketable animals to feed. Despite extensive research on hormonal impacts on cattle physiology, including nutrition and reproduction, there is limited knowledge about how the rumen microbial environment is impacted by pregnancy and feed efficiency in female beef cattle. Understanding the rumen microbiome's role in feed efficiency and its response to hormonal changes during pregnancy is crucial for advancing sustainable beef cattle production. Therefore, this review highlights the importance of understanding the microbial dynamics in the rumen of pregnant beef females. Although progress has been made, gaps remain in understanding how varying nutritional requirements throughout pregnancy affect the rumen microbiome, highlighting the need for continued research. Addressing these areas will lead to more efficient and sustainable cattle production practices, benefiting beef production and contributing to global food security. [ABSTRACT FROM AUTHOR]

Folate metabolism is required for important biochemical processes that regulate cell functioning, but its role in female reproductive physiology in cattle during peri- and post-conceptional periods has not been thoroughly explored. Previous studies have shown the presence of folate in bovine oviductal fluid, as well as finely regulated gene expression of folate receptors and transporters in bovine oviduct epithelial cells (BOECs). Additionally, extracellular folic acid (FA) affects the transcriptional levels of genes important for the functioning of BOECs. However, it remains unknown whether the anatomical and cyclic features inherent to the oviduct affect regulation of folate metabolism. The present study aimed to characterize the gene expression pattern of folate cycle enzymes in BOECs from different anatomical regions during the estrous cycle and to determine the transcriptional response of these genes to increasing concentrations of exogenous FA. A first PCR screening showed the presence of transcripts encoding dihydrofolate reductase (DHFR), methylenetetrahydrofolate reductase (MTHFR), and methionine synthase (MTR) in bovine reproductive tissues (ovary, oviduct and uterus), with expression levels in oviductal tissues comparable to, or even higher than, those detected in ovarian and uterine tissues. Moreover, expression analysis through RT-qPCR in BOECs from the ampulla and isthmus during different stages of the estrous cycle demonstrated that folate metabolism-related enzymes exhibited cycle-dependent variations. In both anatomical regions, DHFR was upregulated during the preovulatory stage, while MTHFR and MTR exhibited increased expression levels during the postovulatory stage. Under in vitro culture conditions, ampullary and isthmic cells were cultured in the presence of 10, 50, and 100 μM FA for 24 h. Under these conditions, isthmus epithelial cells exhibited a unique transcriptional response to exogenous FA, showing a pronounced increase in MTR expression levels. Our results suggest that the expression of folate metabolism-related genes in BOECs is differentially regulated during the estrous cycle and may respond to exogenous levels of folate. This offers a new perspective on the transcriptional regulation of genes associated with the folate cycle in oviductal cells and provides groundwork for future studies on their functional and epigenetic implications within the oviductal microenvironment. • Genes related to folate metabolism enzymes are expressed in bovine oviduct ephitelial cells (BOECs). • DHFR , MTHFR , and MTR expression levels exhibit cycle-dependent variations in BOECs from ampulla and isthmus regions. • MTR is upregulated in isthmus cells cultured with increasing levels of folic acid. • Folate metabolism could have important functional and epigenetic implications in the bovine oviduct. [ABSTRACT FROM AUTHOR]

Simple Summary: Cattle are increasingly exposed to high temperatures with accelerating climate change, presenting the risks of heat stress, poor welfare, and even death. In Australia, the sudden onset of extreme conditions means that deaths are not uncommon. Understanding the impact of high environmental temperatures on cattle behaviour and physiology is critical. We aimed to investigate changes in infrared eye temperature and their association with behavioural responses, such as changes in body postures, alterations in feeding behaviour, and body self-care. Twenty-four Angus steers were individually housed to assess heat load responses when they were fed either a standard finisher diet based on cereal grains or an alternative diet with 8% of the grains replaced by an isoenergetic amount of lucerne hay. No differences were observed between different dietary cohorts. The infrared eye temperature (IRT-Eye), of the steers exposed to high environmental temperatures was increased, and this had a strong association with behaviour and physiology. Cattle with increased IRT-Eye temperature showed stress-related behavioural responses, including a downward-facing head, ears directed backwards, and other indicators of heat stress such as increased panting, standing, and increased rumen temperature. The strong association of IRT-Eye with behaviour and physiology suggests that it can be used to detect heat stress in cattle. Cattle in regions with high ambient temperatures are at risk of heat stress. Early detection is important to allow action to be taken to minimise the risks to cattle exposed to thermal stress. This study aimed to investigate the impact of heat stress on IRT-Eye temperature and its association with the behavioural and physiological responses of heat-stressed Angus steers (n = 24) on finisher and or substituted diets. Overall, 2 cohorts of 12 Angus steers were individually housed in a climate-controlled facility to examine responses to heat stress when fed on a standard finisher diet, based on a high percentage of cereal grains, and on a substituted diet in which 8% of the grains were replaced by an isoenergetic amount of lucerne hay. Exposing feedlot cattle to hot environmental conditions increased IRT-Eye temperature, which had a strong association with behaviour and physiology. There was no evidence of differences between the different dietary cohorts. The cattle with increased IRT-Eye temperature showed stress-related responses, including a downward-facing head, ears directed backwards, and other indicators of heat stress such as increased panting, standing, and increased rumen temperature. The strong association of IRT-Eye temperature with stress-related behaviours, as well as with rumen temperature and panting behaviour, highlights the potential for IRT-Eye to be utilised as a non-invasive tool to assess cattle responses in hot conditions. [ABSTRACT FROM AUTHOR]

The purpose of this research was to determine the correlation between the weight of the ovary, the number of follicles, and the quality of the oocytes from the culling female bovine obtained from the slaughterhouse. The variation may affect the potential of the ovary to produce follicles. Paired ovaries were obtained from female bovines. Follicle numbers were recorded and divided into three size categories (small: 3 mm, medium: < 3 mm-8 mm, and large: > 8 mm). Oocytes were aspirated and the number of oocytes was recorded and graded into four categories (grades A, B, C, and D). There was a positive correlation between the weight of the ovary and the number of follicles, which is 0.560 with the regression equation y = 3.52 + 0.501 x. There was a positive correlation between the number of follicles and the number of oocytes, which is 0.546 with the regression equation y =2.48 + 1.204 x. There was a positive correlation between the number of oocytes and the grade of oocytes, which is 0.520, with the regression equation y = 0.93 + 0.800 x. There was no correlation between the weight of the ovary and oocyte grade A, which is 0.013. [ABSTRACT FROM AUTHOR]

Genome-wide association studies (GWAS) significantly enhance our ability to identify trait-associated genomic variants by considering the host genome. Moreover, the hologenome refers to the host organism's collective genetic material and its associated microbiome. In this study, we utilized the hologenome framework, called Hologenome-wide association studies (HWAS), to dissect the architecture of complex traits, including milk yield, methane emissions, rumen physiology in cattle, and gut microbial composition in pigs. We employed four statistical models: (1) GWAS, (2) Microbial GWAS (M-GWAS), (3) HWAS-CG (hologenome interaction estimated using COvariance between Random Effects Genome-based restricted maximum likelihood (CORE-GREML)), and (4) HWAS-H (hologenome interaction estimated using the Hadamard product method). We applied Bonferroni correction to interpret the significant associations in the complex traits. The GWAS and M-GWAS detected one and sixteen significant SNPs for milk yield traits, respectively, whereas the HWAS-CG and HWAS-H each identified eight SNPs. Moreover, HWAS-CG revealed four, and the remaining models identified three SNPs each for methane emissions traits. The GWAS and HWAS-CG detected one and three SNPs for rumen physiology traits, respectively. For the pigs' gut microbial composition traits, the GWAS, M-GWAS, HWAS-CG, and HWAS-H identified 14, 16, 13, and 12 SNPs, respectively. We further explored these associations through SNP annotation and by analyzing biological processes and functional pathways. Additionally, we integrated our GWA results with expression quantitative trait locus (eQTL) data using transcriptome-wide association studies (TWAS) and summary-based Mendelian randomization (SMR) methods for a more comprehensive understanding of SNP-trait associations. Our study revealed hologenomic variability in agriculturally important traits, enhancing our understanding of host-microbiome interactions. [ABSTRACT FROM AUTHOR]

Lameness is a common problem in Bali cattle. It is caused by various factors, both infectious and non-infectious. This study aims to evaluate the physiological changes in the levels of blood glucose and urinary ketone in lame Bali cattle. This study included 18 Bali cattle with locomotive disorders. Blood glucose levels were assessed from blood samples taken from the jugular vein, while urinary ketone levels were assessed from manually taken urine samples during urination of Bali cattle. The results showed that Bali cattle with locomotive disorders had significantly low blood glucose levels as well as mild to moderate ketonuria and thrombocytosis, which were associated with the increased energy requirements of lame cattle for maintaining postural balance. The results also suggested that the incidence of lameness in Bali cattle was relatively high. [ABSTRACT FROM AUTHOR]

This study investigates differences in farmer income and body weight estimation for male and female Bali cattle in extensive farming in Jaro Subdistrict, Tabalong Regency, South Kalimantan. A random sampling approach was used, involving farmers from nine villages. Statistical analyses revealed a significant difference (p < 0.05) in the body weights of male Bali cattle measured by an animeter compared to those estimated by middlemen. In contrast, no significant difference (p > 0.05) was observed for female Bali cattle. These differences significantly impacted farmer income for male cattle because the income estimated by the animeter exceeded that estimated by the middlemen (p < 0.05). However, no significant difference (p > 0.05) was observed between the two estimation methods for female cattle. In addition, no significant relationship was observed between the estimates made by the middlemen and those made by the animeter for both sexes of Bali cattle. This study used the Monte Carlo simulation to predict demand for male and female Bali cattle in 2024. On average, farmers were able to supply between two and three male Bali cattle and between three to seven female Bali cattle per month. To ensure a steady income, farmers are advised to supply at least one male or female Bali cattle. Moreover, farmer groups are encouraged to compensate for cattle shortages or surpluses, thereby ensuring a stable supply for middlemen and consumers. [ABSTRACT FROM AUTHOR]

Background: The Rembi sheep breed is renowned for its exceptional meat quality and significant economic profit. Nevertheless, there is a gap in research on the hepatic parameters of this breed in Algeria despite the considerable value of the liver in the Algerian population's diet. Objectives: The research aimed to determine the impact of physiological factors (age, physiological stage, and body condition score) on biochemical sheep liver parameters. Methods: Sixty clinically healthy female Rembi breed sheep, aged between 3 months and 7 years, raised at the Technical Institute of Livestock (ITELV) Ksar Chellala Farm in Tiaret Province, Algeria, were selected for biochemical analysis and assessing aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB), and total protein (TP). Results: The concentrations of AST, ALP, and GGT increased significantly (P≤0.001) in young sheep, while ALT and TP levels decreased (P≤0.05). However, a high level of GGT (P<0.001) was also observed in lactating ewes, and during pregnancy, females have a low level of ALP (P<0.001). Furthermore, the body condition score does not affect any of the measurements. Conclusion: Considering the animal's age and physiological stage is critical before interpreting the results. [ABSTRACT FROM AUTHOR]

Simple Summary: Japanese black cattle are a well-known Wagyu cattle breed in Japan, with the best-producing carcass. Based on previous studies and the literature, the existence of the internal carotid artery in cattle still needs to be determined. Thus, this research examined the arterial supply in the brains of Japanese black cattle, especially the presence of the internal carotid artery and its closure at different ages. The internal carotid artery (ICA) is a branch of the common carotid artery (CCA), along with the external carotid artery (ECA), which together provide the blood supply for the brain. The description of the ICA in cattle is vague, including denial of its existence or degeneration at an early stage after birth. This anatomical study investigated the internal carotid artery in Japanese black cattle. Sixty-five heads of Japanese black cattle aged from newborn to 13 years were dissected and injected with colored latex from the CCA after separating the head and body. Diameter measurements of the artery branches from the CCA on its bifurcation were conducted. Furthermore, a histological examination of the ICA wall's structures, which consist of the tunica intima, tunica media, and tunica externa, was performed. The ICA of Japanese black cattle is closed on the left side after age 3 years, except for a small lumen at 13 years, whereas the right ICA remains open at all ages. The location of occlusion of the left internal carotid artery (LICA) shows thickness of the tunica intima and an increased connective tissue layer area. The diameter of the ICA does not differ between the left and right sides, and there is no correlation with age. Therefore, further studies are needed, especially of ICA occlusion related to Japanese black cattle's physiology or cerebrospinal disease. [ABSTRACT FROM AUTHOR]

Sustainable livestock systems should provide high production yields while respecting animal welfare. The silvopastoral system (SPS: silvopastoral-trees, pasture, and cattle) offers a more holistic cattle management strategy, than only pasture system (PAS). The SPS incorporates the production of wood and forage, offering protection for the animals while grazing. However, the relationship between animal behavioral indicators in the SPS has been poorly studied in subtropical conditions. The present study was established to investigate the effect of the SPS on the physiological, behavioral, and health responses during one grazing cycle of the Purunã cattle. Thirty heifers were randomly assigned into two groups of 15 animals, either kept on the SPS or under a monoculture system (PAS: pastoral-cattle on pasture). Body weight and body surface temperature, time of grazing, and lying behavior were assessed for both systems during late Autumn (40 days) in a subtropical humid region of Brazil. The data showed a statistically significant influence of the SPS on the reduction of the heifers’ average body surface temperature, from 27.7 oC to 30.3 oC in PAS (P = 0.02). Although there was an important effect of the SPS on decreasing eating behavior (4.77 events/1.5 h), compared to animals kept in the PAS (6.21 events/1.5 h), the differences in forage availability and quality may have played a role in the animals kept in the SPS. Animals in the SPS presented statistically significantly fewer drinking (P = 0.0001) events, higher body condition score (BCS) decline (P = 0.02), and Rhipicephalus microplus (cattle-tick) score (P = 0.009), than animals maintained on the PAS. There was an aggregated tick distribution, and infested animals lost (high tick score) significantly more weight (P = 0.0216) than non-infested ones (low tick score) under SPS conditions. More studies are required to understand better the influence of multiple factors on Purunã behavior and health, especially when considering distinct agricultural systems, forage availability, geographical and subtropical-humid (Cfb) climate conditions, and the impact of ectoparasites on animal performance. [ABSTRACT FROM AUTHOR]

Simple Summary: Rumination is important for the digestive physiology of cattle and can currently be continuously recorded by sensor technologies. Although a decrease in rumination time is associated with several disorders, it often does not lead farmers to take specific action. In this study, we monitored rumination activity with the use of an ear-tag-based accelerometer system. To investigate the association between a decrease in rumination time and the digestive physiology of dairy cows, we compared rumen fluid characteristics between cows with accelerometer-based health alerts and matched healthy counterparts. Cows with health alerts showed greater variations in rumen fluid characteristics during the health alerts than healthy cows. Monitoring rumination activity is considered a useful indicator for the early detection of diseases and metabolic disorders. Accelerometer-based sensor systems provide health alerts based on individual thresholds of rumination times in dairy cows. Detailed knowledge of the relationship between sensor-based rumination times and rumen physiology would help detect conspicuous animals and evaluate the treatment's success. This study aimed to investigate the association between sensor-based health alerts and rumen fluid characteristics in Holstein-Friesian cows at different stages of lactation. Rumen fluid was collected via a stomach tube from 63 pairs of cows with and without health alerts (ALRT vs NALRT). Pairs were matched based on the day of lactation, the number of lactations, and health criteria. Rumen fluid was collected during and after health alerts. The parameters of color, odor, consistency, pH, redox potential, sedimentation flotation time, and the number of protozoa were examined. Results showed differences between both groups in odor, rumen pH, sedimentation flotation time, and protozoan count at the first rumen fluid collection. Within the groups, greater variations in rumen fluid parameters were found for ALRT cows compared to NALRT cows. The interaction between health alert and stage of lactation did not affect the rumen fluid parameters. [ABSTRACT FROM AUTHOR]

Simple Summary: The general consensus on maternal behavior in free-ranging beef cattle was reviewed. Factors which may affect the display of these behaviors were also explored and provide important information relevant to calf survival and performance. A key aspect of the maternal instinct in all mammals relates to an intricate interplay of various hormones and neurotransmitters around the time of parturition. The influence of these hormones on regulating and initiating maternal behavior in a number of species were also described to provide unique insights for predicting maternal behavior in cattle. Lastly, current methods of measuring behavior were additionally summarized. Bovine maternal behavior is known to be influenced by a variety of factors including hormonal mediation, breed, age, parity, host genetics and general management practices. Following centuries of varying levels of domestication processes, the behavior of the bovine cow has altered from that of her original wild ungulate ancestors, although many maternal instincts have remained unchanged. The influence of maternal behavior on calf health and performance is of interest to cow-calf beef production operations, as in most instances, the cow is solely responsible for rearing the calf until weaning. However, investigating the magnitude of this influence is challenging, in part because objective measurement of behavioral traits is difficult, particularly in extensive settings. In recent years, while a number of remote monitoring devices have been developed that afford opportunities for objective measurement of behavioral traits in livestock, characterization of physiological mechanisms that underlie superior maternal behavior, including identification of potential biomarkers remains elusive in cattle. Hormonal profiles during the periparturient period have been shown to influence behavioral patterns in both current and future generations in other mammalian species and may provide insights into the physiology of bovine maternal behavior. Therefore, the aim of this review is to describe general characteristics of bovine maternal behavior and the factors known to influence it, including hormonal drivers, through which cross-reference to other species is made. Current methods of measuring and assessing behavior that may also be applicable to most production settings have also been reviewed. At present, there is no known hormonal assay that can be used to measure and/or reliably predict bovine maternal behavior post-calving or across generations. Being able to objectively assess superior maternal behavior, whether that be through remote monitoring, hormonal profiling or indirectly through measuring calf performance will be beneficial to livestock industries in the future. [ABSTRACT FROM AUTHOR]

Climate change affects animal physiology. In particular, rising ambient temperatures reduce animal vitality due to heat stress and this can be observed at various levels which included genome, transcriptome, and microbiome. In a previous study, microbiota highly associated with changes in cattle physiology, which included rectal temperature, drooling score and respiratory score, were identified under heat stress conditions. In the present study, genes differentially expressed between individuals were selected representing different additive genetic effects toward the heat stress response in cattle in their production condition. Moreover, a correlation network analysis was performed to identify interactions between the transcriptome and microbiome for 71 Chinese Holstein cows sequenced for mRNA from blood samples and for 16S rRNA genes from fecal samples. Bioinformatics analysis was performed comprising: i) clustering and classification of 16S rRNA sequence reads, ii) mapping cows' transcripts to the reference genome and their expression quantification, and iii) statistical analysis of both data types--including differential gene expression analysis and gene set enrichment analysis. A weighted co-expression network analysis was carried out to assess changes in the association between gene expression and microbiota abundance as well as to find hub genes/microbiota responsible for the regulation of gene expression under heat stress. Results showed 1,851 differentially expressed genes were found that were shared by three heat stress phenotypes. These genes were predominantly associated with the cytokine-cytokine receptor interaction pathway. The interaction analysis revealed three modules of genes and microbiota associated with rectal temperature with which two hubs of those modules were bacterial species, demonstrating the importance of the microbiome in the regulation of gene expression during heat stress. Genes and microbiota from the significant modules can be used as biomarkers of heat stress in cattle. [ABSTRACT FROM AUTHOR]

Simple Summary: The evacuation of farm animals out of a barn is a rarely considered subject. Especially in case of fire, there is a need for functional emergency exits as well as concepts of rescue for swift evacuation, since both the harmful smoke and the danger of collapsing roofs call for urgency. Field reports of firefighters and affected farmers state that barn animals hesitate to leave their familiar surroundings and rather try to withdraw to their known housing, which they deem as safe. Thus, it is not sufficient to simply open the doors and gates hoping for self-rescue of the animals. As there is a lack of guidelines on the design of emergency exits, we conducted an evacuation exercise of year-round housed dairy cattle, in cooperation with the fire brigade by night, to inspect the animals' behaviour. We found that preparing the exits according to the sensory perception of cattle, providing familiar surfaces and adequate lighting, and herding cattle correctly result in a speedy rescue, even if the animals were not habituated to leaving the barn before. We hope to set an example for farmers and fire brigades that are in need of instructions, and that more research considering this vital topic will follow. The aim of this study was to investigate the influencing factors of successfully rescuing year-round housed cattle in case of a barn fire. Empirical research indicates the reluctance of cattle to leave their familiar barn. Subsequent retreat back to the perceived safety inside, which stands in contrast to the unknown and thus adversary elements outside, for example, the fire brigade, is to be expected. We examined the evacuation of 69 dairy cattle, split into three groups, to an adjacent pasture by night and inspected the animals' acceptance of two differently designed escape routes and the effect of preceding training. Along with the time needed for evacuating all animals, we measured faecal cortisol metabolites and daily milk yield to assess stress in the animals. Our preliminary assumption was that cattle trained for pasture would have a decisive advantage over untrained cattle. However, adapting the exits to the sensory physiology of the cattle resulted in an extensive impact on the animals' readiness to leave the familiar housing, as the evacuation of the cattle non-habituated to the exit was comparatively quick and successful. We consider this study instructional for fire brigades and farmers, encouraging them to develop a customised concept for rescuing their cattle in case of an emergency. [ABSTRACT FROM AUTHOR]

There have never been specific research or study about cattle health during shipment using a Camara Nusantara ship as a mode of transportation. The objective of this study was to investigate the ship environment and physiological responses of cattle during transport from Tenau Port (Kupang) to Tanjung Priok Port (Jakarta) using Camara Nusantara 3 ship. The sample of 12 Bali cattle was determined using the purposive sampling total of 250 Bali cattle during transportation. Physiological parameters (including rectal temperature, respiratory rate, pulse rate) were used to evaluate the welfare status and stress level of animals, during the respective transport journeys. Transient changes in physiological parameters were found in the transported animals from day 2 to 4 relative to baseline levels, and the values were within the mild stress level of physiological range for the age of animals involved. There were significant differences (P

Heat stress negatively affects health and production in cows. Examining the cellular response to heat stress could reveal underlying protective molecular mechanisms associated with superior resilience and ultimately enable selection for more resilient cattle. This type of investigation is increasingly important as future predictions for the patterns of heat waves point to increases in frequency, severity, and duration. Cows identified as high immune responders based on High Immune Response technology (HIR) have lower disease occurrence compared to their average and low immune responder herd-mates. In this study, our goal was to identify epigenetic differences between high and low immune responder cows in response to heat stress. We examined genome-wide DNA methylation of blood mononuclear cells (BMCs) isolated from high and low cows, before and after in vitro heat stress. We identified differential methylation of promoter regions associated with a variety of biological processes including immune function, stress response, apoptosis, and cell signalling. The specific differentially methylated promoter regions differed between samples from high and low cows, and results revealed pathways associated with cellular protection during heat stress. [ABSTRACT FROM AUTHOR]

Heat stress is an environmental factor that negatively affects the morphological and physiological properties of dairy cattle. The aim of this study is to investigate the relationship between heat stress and milk yield, milk fat ratio and body temperature in Holstein-Friesian dairy cattle. The data of the study was obtained from a private Kurtalan Farm of Siirt province, the Southeastern Anatolia Region of Turkey. Milk yield and other traits of 13 head Holstein- Friesian dairy cattle were recorded in March, April, May, June, July, August and September. In addition, temperature and humidity records were recorded in the farm and in the parlor to be used for calculating the temperature humidity index value. In the analysis of data, correlation and regression methods were used. As a result of the study, the negative correlation (P<0.01) was found between milk yield and milk fat ratio and the positive correlation (P<0.001) were detected between heat stress and body temperature. In addition, a significant negative relationship was observed between rectal temperature and milk yield (P<0.01). [ABSTRACT FROM AUTHOR]

An alarming number of large mammalian species with low reproduction rates is threatened with extinction. As basic knowledge of reproductive physiology is currently lacking in many species, increasing the understanding of reproductive physiology is imperative and includes the development of novel artificial reproduction technologies. Despite the relatively comprehensive knowledge on molecular mechanisms underlying reproduction in livestock species such as cattle, pregnancy failures are likewise far from understood. Contrary to other wildlife species, the European roe deer (Capreolus capreolus) displays a remarkably high pregnancy rate. In parts, cattle and roe deer exhibit comparable features of preimplantation embryo development. Therefore, understanding the high fertility rate in the roe deer holds a great potential for cross-species knowledge gain. As the only known species among the artiodactylae, the roe deer displays a long period of embryonic diapause. The preimplantation blastocyst reaches a diameter of 1 mm only at around 4 months compared to around 13 days post estrus in cattle. The expanded blastocyst survives in a uterine microenvironment that contains a unique set of yet unidentified factors that allow embryonic stem cells to proliferate at low pace without impairing their developmental potential. Upon reactivation, intimate embryo-maternal communication comparable to those reported in cattle is thought to occur. In this review, current knowledge, parallels and differences of reproductive physiology in cattle and roe deer are reviewed. The roe deer is proposed as a unique model species to (1) enhance our knowledge of fertility processes, (2) define factors that support embryo survival for an extended period, (3) advance knowledge on embryonic stem cells, and (4) unravel potential implications for the development of novel strategies for artificial reproductive technologies. [ABSTRACT FROM AUTHOR]

Understanding the impacts of nutrition on reproductive physiology in cattle are fundamental to improve reproductive efficiency for animals under different nutritional conditions. Starting on Day 0 (day of ovulation) until next ovulation, Holstein heifers (n = 24) were fed: low energy diet (ad libitum grass hay; LED) and high energy diet (ad libitum grass hay + concentrate supplement; HED). Heifers on HED gained more weight (average daily gain: 0.824 ± 0.07 vs 0.598 ± 0.09 kg/day) and had increased insulin concentrations. The dominant follicle of wave 1 in HED had greater growth rate overall from Days 0 to 8 and on Days 6--7 and 8--9 and started atresia later. The dominant follicle of wave 2 in HED had greater growth rate overall from Day 9 to 18 and on Days 14--15 and 15--16. In two-wave patterns, there was no difference in estradiol or progesterone concentrations but concentrations of FSH were lower in HED on Days 15 and 16. Estradiol concentrations increased earlier in two-wave patterns in association with earlier luteolysis. The frequency of two follicular waves was greater in HED than LED (11/12 vs 6/11; 92.7% vs 54.5%). In conclusion, an acute increase in dietary energy altered not only growth rate of the dominant follicle but also follicular wave pattern in heifers by increasing frequency of two follicular waves. The hypotheses were supported that an acute increase in dietary energy (1) prolongs growth period of dominant follicles and (2) alters follicular wave pattern in heifers. [ABSTRACT FROM AUTHOR]

Rising temperatures caused by climate change have adverse effects on cattle physiology, welfare, health, and reproduction. Heat stress in cows affects the oocyte and embryo directly through heat shock on cellular function. Fewer data are available on the effect of high temperatures on male fertility. Temperature-humidity index (THI) is a measure for assessing the risk of heat stress that combines the effects of temperature and humidity. The aim of this study was to determine the relationship between THI and fresh or frozen–thawed sperm quality of Holstein bulls kept in temperate climates. Bull sperm data of 29,170 ejaculates from 933 bulls collected at 3 Dutch artificial insemination centers between 2015 and 2018 were evaluated. The assessed variables included total sperm motility and morphology of fresh semen, and total sperm motility, morphology, and progressive motility of frozen semen 0 and 3 h after thawing. In addition, 56-d nonreturn rates were analyzed. The assessed effects were season and THI on the day of semen collection and during spermatogenesis (30 d before collection), bull, age of bull, year, and location. Bulls were divided into 2 categories according to their age: young (<36 mo) and older (>36 mo). Overall sperm quality of young bulls improved as age increased. No effect of THI on fresh sperm variables was observed in either young or older bulls. However, high THI at spermatogenesis negatively affected the cryotolerance of sperm cells. Sperm cells from young and older bulls showed a pronounced decrease (14–18%) of the assessed variables 3 h after thawing after the increase of THI during spermatogenesis in autumn. Remarkably, older bulls were more sensitive to THI at spermatogenesis compared with semen collection, showing up to a 3.8 times higher negative effect on frozen sperm quality. However, an elevated THI at semen collection produced a tendency toward decreased 56-d nonreturn rates as the age of the bull increased. Although this decrease was up to 4%, rising temperatures may still cause important economic losses in the future. For the first time, the present study confirmed that climate compromises not only sperm quality, but also dairy bull fertility. [ABSTRACT FROM AUTHOR]

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The present study evaluated the interaction effects of n-3 fatty acids (from linseed oil (LSO), 0 v. 2·5, % DM basis) with rumen undegradable:degradable protein (RUP:RDP) ratios (low ratio (LR) 27:73; high ratio (HR) 38:62 based on crude protein %) in dairy calves' starter diet. Forty-eight 3-d-old female Holstein dairy calves (41·5 kg of body weight (BW)) were allocated in a 2 × 2 factorial arrangements in the following treatments (n 12 calves/each): (1) no supplementation of LSO with LR (NLSO-LR); (2) no supplementation of LSO with HR (NLSO-HR); (3) supplementation of LSO with LR (LSO-LR) and (4) supplementation of LSO with HR (LSO-HR). The calves were weaned on day 53 of the experiment and remained in the study until day 73. Intake was not affected by LSO and RUP:RDP ratio. However, average daily gain (ADG) was improved with LSO supplementation. Feeding the HR diet increased ADG compared with the LR diet during the entire period. Final BW was greater in calves fed on the LSO than those fed the NLSO diet. Microbial protein production did not differ among treatments. Calves fed on LSO diets had greater feed efficiency than those which were not fed on LSO diets. The calves supplemented with LSO had greater wither and hip heights compared with the unsupplemented calves. The glucose, cholesterol, HDL and insulin concentrations increased in calves supplemented with LSO. In conclusion, the HR diet improved calves' performance post-weaning; however, LSO could enhance growth performance of dairy calves during the pre-weaning period. [ABSTRACT FROM AUTHOR]

Background: Small intestinal starch digestion in ruminants is potentially limited by inadequate production of carbohydrases. Previous research has demonstrated that small intestinal starch digestion can be improved by postruminal supply of casein or glutamic acid. However, the mechanisms by which casein and glutamic acid increase starch digestion are not well understood.Objectives: The objective of this experiment was to evaluate the effects of duodenal infusions of starch with casein or glutamic acid on postruminal carbohydrase activities in cattle.Methods: Twenty-two steers [mean body weight (BW) = 179 ± 4.23 kg] were surgically fitted with duodenal and ileal cannulas and limit-fed a soybean hull-based diet containing small amounts of starch. Raw cornstarch (1.61 ± 0.0869 kg/d) was infused into the duodenum alone (control), or with 118 ± 7.21 g glutamic acid/d, or 428 ± 19.4 g casein/d. Treatments were infused continuously for 58 d and then steers were killed for tissue collection. Activities of pancreatic (α-amylase) and intestinal (maltase, isomaltase, glucoamylase, sucrase) carbohydrases were determined. Data were analyzed as a randomized complete block (replicate group) design using the GLM procedure of SAS to determine effects of infusion treatment.Results: Duodenal casein infusion increased (P < 0.05) pancreatic α-amylase activity by 290%. Duodenal glutamic acid infusion increased (P < 0.03) duodenal maltase activity by 233%. Duodenal casein infusion increased jejunal maltase (P = 0.02) and glucoamylase (P = 0.03) activity per gram protein by 62.9% and 97.4%, respectively. Duodenal casein infusion tended to increase (P = 0.10) isomaltase activity per gram jejunum by 38.5% in the jejunum. Sucrase activity was not detected in any segment of the small intestine.Conclusions: These results suggest that small intestinal starch digestion can be improved in cattle with increased small intestinal flow of casein through increases in postruminal carbohydrase activities. [ABSTRACT FROM AUTHOR]

Animals have precise recognition systems for amino acids and peptides that regulate their feeding behavior as well as metabolic responses. Because of their particular gastrointestinal structure, ruminants are expected to have unique mechanisms of amino acid regulation in the digestive tract. To better understand these mechanisms in the ruminant digestive tract, the expression of Tas1r3 and Pept1 was studied along the gastrointestinal tract of Japanese Black cattle through quantitative RT-PCR and immunohistochemistry. Tas1r3 mRNA was detected ubiquitously along the gastrointestinal tract, and the most predominant expression was observed in the reticulum. In addition, the presence of Tas1r3 receptor was confirmed in the rumen through immunohistochemistry. The expression level of Pept1 mRNA was higher in the forestomach (rumen, reticulum, and omasum) and small intestine (duodenum) than that in the tongue, and predominant expression was observed in the rumen. By contrast, a negligible amount of Pept1 mRNA was detected in the abomasum and large intestine. Further studies on the roles of Tas1r3 and Pept1 in the digestive tract, in particular, in the four components of the stomach, will help us to understand the mechanisms of amino acids regulation in ruminants and provide the basis for formulating cattle diets to improve the health and productivity of cattle. [ABSTRACT FROM AUTHOR]

Following the recent breakthrough of total structural determination of a Au-thiolate nanocluster [P. Jadzinsky et al., Science 318, 430 (2007)], extensive interests have been stimulated to unveil (or revisit) the structure-property relationship of various thiolate-Au nanostructures in light of the new finding of –SR–(Au–SR)x– “staple” motif. Here, we present experimental x-ray absorption spectroscopy (XAS) and x-ray photoelectron spectroscopy (XPS) results on the local structure and electronic properties of thiolate-protected Au nanocluster encapsulated in bovine serum albumin (Au-BSA) together with theoretical calculation of projected local density of states (l-DOS) of Au25(SR)18 model cluster. Analysis of the Au L3-edge extended x-ray absorption fine structure (EXAFS) of Au-BSA suggested that the nanocluster is Au25 with Au-thiolate “staple” motif. X-ray absorption near-edge structure (XANES) and Au 4f XPS were used to probe the electronic behavior of Au-BSA. The Au d-electron density of Au-BSA was found to decrease by 0.047 e- relative to that of the bulk. A self-consistent real space Green’s function approach implemented in ab initio FEFF8 program was used to calculate the l-DOS of Au25(SR)18 and other model clusters from a site-specific perspective. The theoretical results are in good agreement with the experimental d-DOS data of Au-BSA and, importantly, systematically illustrate the effect of Au-thiolate “staple” motif on the electronic behavior of Au25(SR)18. The present work sheds light on the structure-property relationship of thiolate-protected Au25 from both experimental and theoretical perspectives and illustrates the usefulness of XAS/l-DOS method in such studies. [ABSTRACT FROM AUTHOR]

Nuclear copies of the mitochondrial DNA (NUMTs) have already been described in several species. In this context, we identified and analysed 166 bovine NUMT regions with a total length of 430 kbp, representing about 0.02% of the cattle nuclear genome. Copies of all mitochondrial regions were detected in the nuclear genome, with distinct degrees of sequence similarity to the mitogenome. Some NUMT regions include large mitogenome segments and show high similarity to the organelle genome sequence. NUMT regions are frequently modified by insertion of repetitive sequences and by sequence rearrangements. We confirmed the existence of 29 NUMT regions by PCR amplification using DNA from the cow (Dominette) which was used to generate the bovine genome reference sequence, ruling out the possibility that these NUMTs could be artifacts of the genome assembly. As there are NUMT regions with high similarity to the mitogenome, special care is needed when designing primers for mitochondrial DNA amplification. Our results can therefore be used to avoid co-amplification of bovine nuclear sequences similar to mitochondrial DNA. [ABSTRACT FROM AUTHOR]

Differences in reproductive physiology between cattle breeds may help to explain distinct responses to assisted reproductive techniques and to define breed-specific protocols with improved efficiency. Germinal vesicle (GV) stage oocytes are characterized by increasing levels of chromatin compaction enclosed within the nucleus (graded from GV0 to GV3), associated with different developmental competence. The first objective of this study was to characterize chromatin configuration of GV stage oocytes recovered by OPU at random days of the estrous cycle from Nelore (Bos indicus) and Holstein (Bos taurus) cows. In Nelore 90% of the oocytes presented advanced stages of chromatin compaction associated with higher developmental competence (GV2 and GV3), while in Holstein, only 65% of the oocytes were at these stages. Then, aiming to obtain a more homogeneous population of oocytes in Holstein, we tested two synchronization protocols combining aspiration of all visible follicles at a random day (day 0), two IM injections of FSH 12 h apart on day 2, and OPU on day 4 (OPU/D4) or 5 (OPU/D5). The protocol OPU/D4 provided around 45% of the oocytes with low chromatin compaction (GV1), while the protocol OPU/D5 provided 70% of the oocytes at GV2 and 20% at GV3. Finally, we assessed the effects of a culture system known to prevent meiotic resumption on chromatin configuration of the GV2 enriched oocyte population obtained with the protocol OPU/D5. After 9 h of culture most oocytes transited from GV2 to GV3, with 90% of the oocytes at GV3 stage. This study demonstrates differences between Nelore and Holstein cows regarding patterns of chromatin configuration that may account for their different performance in IVM/IVF. In addition, it provides novel references for the design of protocols aiming to regulate oocyte quality before IVM for the optimization of IVF outcomes. • Nelore and Holstein display different patterns of oocyte chromatin configuration. • Patterns associated with higher oocyte competence are more frequent in Nelore. • Protocols combining OPU and FSH treatment can homogenize oocytes in Holstein. • Culture with NPPC and steroids can be used to control oocyte chromatin dynamics. [ABSTRACT FROM AUTHOR]

A trend of global warming has been observed over the last few years and it has often been discussed whether there is an effect on livestock. Numerous studies have been published about heat stress in cattle and its influence on the physiology and productivity of animals. Preventing the negative effects of heat stress on cattle is essential to ensure animal welfare, health and productivity. Monitoring and analysis of physiological parameters lead to a better understanding of the adaptation processes. This can help to determine the risk of climate change and its effects on performance characteristics, e.g. milk yield and reproduction. This, in turn, makes it possible to develop effective measures to mitigate the impact of heat load on animals. The aim of this article is to provide an overview of the current literature. Studies especially about the physiological and productive changes due to heat stress in cattle have been summarised in this review. The direction of future research into the aspect of heat stress in cattle is also indicated. [ABSTRACT FROM AUTHOR]

MiR‐24‐3p, a broadly conserved, small, noncoding RNA, is abundantly expressed in mammary tissue. However, its regulatory role in this tissue remains poorly understood. It was predicted that miR‐24‐3p targets the 3′ untranslated region (3′‐UTR) of multiple endocrine neoplasia type 1 (MEN1), an important regulatory factor in mammary tissue. The objective of this study was to investigate the function of miR‐24‐3p in mammary cells. Using a luciferase assay in mammary epithelial cells (MAC‐T), miR‐24‐3p was confirmed to target the 3′‐UTR of MEN1. Furthermore, miR‐24‐3p negatively regulated the expression of the MEN1 gene and its encoded protein, menin. miR‐24‐3p enhanced proliferation of MAC‐T by promoting G1/S phase progression. MiR‐24‐3p also regulated the expression of key factors involved in phosphatidylinositol‐3‐kinase/protein kinase B/mammalian target of rapamycin and Janus kinase/signal transducer and activators of transcription signaling pathways, therefore controlling milk protein synthesis in epithelial cells. Thus, miR‐24‐3p appears to act on MAC‐T by targeting MEN1. The expression of miR‐24‐3p was controlled by MEN1/menin, indicating a negative feedback loop between miR‐24‐3p and MEN1/menin. The negatively inhibited expression pattern of miR‐24‐3p and MEN1 was active in mammary tissues at different lactation stages. The feedback mechanism is a new concept to further understand the lactation cycle of mammary glands and can possibly to be manipulated to improve milk yield and quality. MiR‐24‐3p negatively modulates the expression of MEN1/menin in mammary epithelial cells by targeting the 3 'UTR of MEN1. MiR‐24‐3p plays regulatory role of cell proliferation and milk protein synthesis in mammary epithelial cells through cooperatively acting with menin. [ABSTRACT FROM AUTHOR]

Three hundred and sixteen bovine livers were inspected during slaughtering at Urmia Abattoir in May 2016. Eighty-nine inspected livers have various gross and microscopic lesions. 89 hepatic tissue samples were processed routinely and stained by Harris Hematoxylin and Eosin (H&E), Periodic Acid- Schiff reagent (PAS) and Sudan IV for frozen sections. Hepatic lesions were observed in 89 samples (28.16%) of 316 liver samples. lesions in the inspected cattle were consisted 33/316 (10.44%) fatty change, 40/316 (12.65%) fascioliasis, 8/316 (2.53%) hydatid cyst, 6/316 (1.89%) focal coagulative necrosis and 2/316 (0.63%) hemorrhage. The results show that abundance of hepatic fatty change in male cattle is more than females. Indeed, abundance of mild type of hepatic fatty change 15/33 (45.45%) is more than moderate type 11/33 (33.33%) and severe type 7/33 (21.21%). According to presence of hepatic fatty change in most livers affected by fascioliasis, it seems fascioliasis may be a cause of hepatic fatty change in cattle slaughtered at Urmia Abattoir. [ABSTRACT FROM AUTHOR]

Chemical immobilization is necessary for the physiological study of large wild animals. However, the immobilizing drugs can adversely affect the cardiovascular and respiratory systems, yielding data that do not accurately represent the normal, resting state. We hypothesize that these adverse effects can be ameliorated by reversing the immobilizing agent while holding the animal under general anaesthesia. We used habituated sheep Ovis aries (N = 5, 46.9 ± 5.3 kg body mass, mean ± SEM) and goats Capra hircus (N = 4, 27.7 ± 2.8 kg) as ungulate models for large wild animals, and measured their cardiorespiratory function under three conditions: (1) mild sedation (midazolam), as a proxy for the normal resting state, (2) immobilization (etorphine and azaperone), and (3) general anaesthesia (propofol) followed by etorphine antagonism (naltrexone). Cardiac output for both sheep and goats remained unchanged across the three conditions (overall means of 6.2 ± 0.9 and 3.3 ± 0.3 L min−1, respectively). For both sheep and goats, systemic and pulmonary mean arterial pressures were significantly altered from initial midazolam levels when administered etorphine + azaperone, but those arterial pressures were restored upon transition to propofol anaesthesia and antagonism of the etorphine. Under etorphine + azaperone, minute ventilation decreased in the sheep, though this decrease was corrected under propofol, while the minute ventilation in the goats remained unchanged throughout. Under etorphine + azaperone, both sheep and goats displayed arterial blood hypoxia and hypercapnia (relative to midazolam levels), which failed to completely recover under propofol, indicating that more time might be needed for the blood gases to be adequately restored. Nonetheless, many of the confounding cardiorespiratory effects of etorphine were ameliorated when it was antagonized with naltrexone while the animal was held under propofol, indicating that this procedure can largely restore the cardiovascular and respiratory systems closer to a normal, resting state. [ABSTRACT FROM AUTHOR]

The size and body condition of cows can affect their reproductive efficiency. However, few studies reported genetic correlations between these traits in beef cattle. Thus, we estimated the genetic parameters and correlations between weight (MW), height (MH) and body condition score (BCS) of cows and reproductive traits (SC: scrotal circumference, AFC: age at first calving, GL: gestation length, DC: days to calving, and CI: calving interval) in Nelore animals. In addition, it has also obtained direct and correlated responses aiming at determining whether changes in cow size and body condition may affect the herd reproductive performance. A series of two-trait Bayesian analyzes were performed including MW, MH or BCS with each of the reproductive traits. The heritability estimated for MW, MH and BCS were 0.46 ± 0.02, 0.35 ± 0.01 and 0.17 ± 0.02, indicating an involvement of additive gene action mainly in cows' size determination. For the reproductive traits of females, heritability ranged from 0.05 ± 0.00 for CI to 0.18 ± 0.01 for GL, and was 0.37 ± 0.01 for SC. Low repeatability were estimates for GL (0.19 ± 0.00), DC (0.19 ± 0.00) and CI (0.05 ± 0.00). The MW was positive correlated with AFC (0.23 ± 0.08), CI (0.25 ± 0.15) and, with lower magnitude, of GL (0.14 ± 0.03). Null genetic correlations were obtained between MW with SC (0.03 ± 0.03) and DC (−0.01 ± 0.04). The MH showed positive and low genetic association with all female reproductive traits, but negative with SC (−0.08 ± 0.03). Negative and favorable genetic correlations were estimated between BCS and females reproductive traits, but unfavorable with SC (−0.13 ± 0.06). In summary, the negative impact of increase the size of Nelore females on their reproductive performance is expected to be small in tropical regions. The use of sires with high genetic breeding values for SC should result in slight reduction of BCS of cows, but no effective genetic response in female size is expected. Selection based on BCS should promote little improvement in reproductive efficiency of cows. [ABSTRACT FROM AUTHOR]

Currently, very limited information is available on the growth of alpacas (Vicugna pacos) . The aim of this study was to describe the growth of alpacas with percentile curves and to generate an equation for precise estimating the body weight using a body height, length or circumference. 162 alpacas, ranging in age from a few days to 36 months, were measured over a period of twelve months. Every two weeks five different body parameters and the body weight were recorded. The resulting percentile curves describe the development of body weight, height at withers, height in the hip and length of the trunk of up to three year old alpacas. No significant differences in the development of the skeleton were determined between males and females as well as the two subspecies Huacaya and Suri (P > 0.01). As in other species, the thoracic circumference is a reliable parameter for estimating the body weight. The equation based on to the model of a cubic function allows a very accurate prediction of the body weight (R 2 = 0.97). The results provide new data about the growth pattern of alpacas. Based on the data guidelines concerning the growth of alpacas were created for veterinarians, alpaca owners and breeders. They supply a solid basis for recommendation in feeding and management of reproduction. Using the percentile curves, a reliable prediction of growth and conclusions regarding the age of an alpaca are possible. [ABSTRACT FROM AUTHOR]

The process of pre-extraction is an important stage in the process of collagen synthesis. This stage increases the sensitivity of collagen molecule chains that can affect production yields and collagen properties. The objectives of the study were to synthesize and evaluate halal collagen from Bali cattle's hide on different -extracting processes. A total of 5 treatments applied in this study, namely: T1 = Ca(OH)2 5% (b/v) ; T2 = Ca(OH)2 15% (b/v) ; T3 = Ca(OH)2 5% + CH3COOH 5%(b/v) ; T4 = Ca(OH)2 15% + CH3COOH 5% (b/v). Each treatment was repeated 4 times. Data were analyzed in a variety of ways using SPSS program. The observed parameters consisted of: 1) yield, 2) viscosity and 3) pH. The results showed that the difference in real pre-extracting process increased the yield and viscosity, but not the pH value. The application of T4 treatment provided the best results compared to other treatments as well as controls to increase the yield and also improve the collagen's physical properties and pH. [ABSTRACT FROM AUTHOR]

Six healthy Murrah buffalo were assessed for middle uterine artery and fetal umbilical blood flow at regular interval from day 18 of gestation onward. Resistance index and pulsatility index of middle uterine artery was invariably similar (p>0.05) from day 30 of gestation onward. However, these indices exhibited a decreasing (p<0.05) trend till nine-month of gestation in fetal umbilicus. In brief, the doppler indices of fetal umbilicus suggested the decrease in resistance of blood flow to the fetus. [ABSTRACT FROM AUTHOR]

Feet and leg conformation is evaluated as a subset of conformational structure traits in dairy and beef cattle and is related to the feet and leg quality that can compromise the animals' productive performance and longevity. The aim of this study was to perform a genome-wide association study (GWAS) of two traits related to feet and leg conformation in Nellore cattle to identify chromosomal regions related to the expression of these traits. Phenotypic and pedigree data from 104,725 animals and genotypes from 1,435 animals and 407,730 SNPs were used. Feet and leg structure was evaluated as a binary trait (FL1) to identify yearling animals with feet and leg problems or as categorical score (FL2) to assess the overall quality of their feet and leg. The top ten 1-Mb windows that explained the largest proportion of the total genetic variance were identified and functional enrichment analyses were performed. The 10 windows with large effects obtained for FL1 are located on chromosomes 1, 2, 6, 7, 8, 10, and 14, and together explained 8.96% of the additive genetic variance. For FL2, these windows are located on chromosomes 1, 7, 10, 11, 18, 20, 22, 28, and 29, explaining 8.98% of the additive genetic variance. Several candidate genes were identified, including DLX2 which is associated with osteogenic differentiation, IL-1ß and IL-1A associated with some properties of articular cartilage, PiT1 which plays an important role in bone physiology, and CTSL associated with rheumatoid arthritis. The results presented here should contribute to a better understanding of the genetic and physiologic mechanisms regulating both traits, and identifies candidate genes for future investigation of causal mutations. [ABSTRACT FROM AUTHOR]

A single dose protocol of FSH for superstimulation in cattle may improve compliance and superovulatory response. A single subcutaneous (sc) administration of pFSH was efficacious, but response depended on body condition and injection site; the adipose tissue pad behind the shoulder was most efficacious. Inconsistent results in Holsteins were partially overcome by sc administration of 75% of the total pFSH dose behind the shoulder on the first day followed by 25% 48 h later. An alternative would be to combine FSH with polymers that cause it to be released slowly over several days. Hyaluronan is found normally in most animal tissues and is nonreactive when administered parentally. A single intramuscular (im) administration of pFSH in a 2.0% hyaluronan induced a superovulatory response that did not differ from twice daily im administration over 4 d. However, 2.0% hyaluronan was viscous and difficult to mix with FSH. Although solutions of 1.0 and 0.5% hyaluronan were less viscous, they lacked efficacy as a single im administration. However, superovulatory response was high when either 1.0 or 0.5% hyaluronan was used in a two-dose im protocol; two-thirds on the first day and one-third 48 h later. A single im administration of FSH in 0.5% hyaluronan effectively induced superstimulation for OPU in cattle. Successful superovulation in the cow was associated with circulating FSH levels that were similar to endogenous FSH levels prior to follicular wave emergence; however, levels must be maintained above baseline for at least 72 h, or 36 h for OPU. Circulating FSH levels following a single sc administration of 400 mg NIH-FSH-P1 behind the shoulder in beef cows increased to 1.0 or 1.2 ng/mL at 12 h and were back near baseline in approximately 60 h, while FSH levels following im administration of 200 mg NIH-FSH-P1 in 0.5% hyaluronan into Holstein donors reached 1.5 ng/mL at 12 h and returned to baseline in approximately 36 h. [ABSTRACT FROM AUTHOR]

Background: The potential of circulating miRNAs as biomarkers of tissue function, both in health and disease, has been extensively demonstrated in humans. In addition, circulating miRNA biomarkers offer significant potential towards improving the productivity of livestock species, however, such potential has been hampered by the absence of information on the nature and source of circulating miRNA populations in these species. In addition, many miRNAs originally proposed as robust biomarkers of a particular tissue or disease in humans have been later shown not to be tissue specific and thus to actually have limited biomarker utility. In this study, we comprehensively analysed miRNA profiles in plasma and cell fractions of blood from cattle with the aim to identify tissue-derived miRNAs which may be useful as biomarkers of tissue function in this important food animal species. Results: Using small RNA sequencing, we identified 92 miRNAs with significantly higher expression in plasma compared to paired blood cell samples (n = 4 cows). Differences in miRNA levels between plasma and cell fractions were validated for eight out of 10 miRNAs using RT-qPCR (n = 10 cows). Among miRNAs found to be enriched in plasma, we confirmed miR-122 (liver), miR-133a (muscle) and miR-215 (intestine) to be tissue-enriched, as reported for other species. Profiling of additional miRNAs across different tissues identified the human homologue, miR-802, as highly enriched specifically in liver. Conclusions: These results provide novel information on the source of bovine circulating miRNAs and could significantly facilitate the identification of production-relevant tissue biomarkers in livestock. In particular, miR-802, a circulating miRNA not previously identified in cattle, can reportedly regulate insulin sensitivity and lipid metabolism, and thus could potentially provide a specific biomarker of liver function, a key parameter in the context of post-partum negative energy balance in dairy cows. [ABSTRACT FROM AUTHOR]

Despite the recent advances in transcriptomics, gene expression studies addressing cattle´s skeletal muscle adaptations in response to compensatory growth are warranted, particularly regarding lipid metabolism due to its impact in meat sensory and nutritional traits. In the present study, in comparison to ad libitum feeding, a period of feed restriction was used in order to understand the changes in bull´s lipid metabolism and gene expression of the adipogenic and lipogenic pathways after re-alimentation. Thus, 40 young Alentejana bulls were either fed ad libitum (CG group) from 9 to 18 months of age or subjected to food restriction from 9 to 15 months of age, and fed ad libitum until 24 months of age (DG group). The intramuscular fat (IMF) and total fatty acids (FA) contents were similar between groups. The major FA (>2%) contents were similar (16:0, 16:1c9, 18:1c9 and 18:2n-6) between treatments with the exception of 18:0 content that was 15% lower in DG than in CG and 20:4n-6 that tended to be greater on DG bulls. Regarding minor FA (<2%), the DG group presented greater proportions (P<0.01) of 17:1c9, 18:1t9, 18:1t10 (, 18:1c11), 18:1c13, 18:3n-6, 22:0, 22:4n-6 and 22:6n-3 and lower (P<0.05) proportions of 20:0, 18:1t16+c14, and branched chain FA (iso-15:0, anteiso-15:0, iso-16:0 and anteiso-17:0) than the CG group. Delta-9 desaturase activity indices were consistently greater (P<0.05) in DG, when compared to the CG group. Regarding microarray analysis, differentially expressed genes between CG and DG bulls were grouped in 5 main biological functions: lipid and nucleic acid metabolisms, small molecule biochemistry, molecular transport and translational modification. Discontinuous growth down-regulated the expression of ACACB (FC (fold-change) = 1.32), FABP3 (FC = 1.45), HADHA (FC = 1.41) and SLC37A4 (FC = 1.40) genes, when compared to the CG system (FDR<0.05). In contrast, in the CG bulls, the expression of ELOVL5 (FC = 1.58) and FASN (FC = 1.71) was down-regulated when compared to DG bulls. These results were confirmed to be significant (P<0.05) in the case of ELOVL5, FASN and SLC37A4, and almost significant for FABP3 by qRT-PCR analysis. The SCD1 and SCD5 gene expressions were not found to be affected by growth path. These results contribute to the still scarce knowledge about the mechanisms involved in fatty acid metabolism during compensatory growth which have decisive role on meat quality produced in Mediterranean areas. [ABSTRACT FROM AUTHOR]

It is known that physiological overproduction of nitric oxide (NO) contributes to oxidative stress and inflammation. Our published studies indicated that vitamin A (VA) reduces NO-induced oxidative stress in bovine mammary epithelial cells (BMECs) by increasing antioxidant enzyme activities. However, the precise mechanism is unclear. The present study was conducted to examine the protective effects of VA on NO-induced damage to BMECs in vitro using diethylenetriamine nitric oxide (DETA-NO) as the NO donor and to explore the intracellular signaling mechanisms of VA that involve nuclear factor erythroid 2-related factor (Nrf2) and nuclear factor kappa-B (NF-κB). Subconfluent BMECs were divided into 10 treatment groups with 6 replicates per treatment and were cultured with dimethyl sulfoxide (DMSO, vehicle negative control) or 0, 0.05, 0.1, 0.2, 0.5, 1, 2, 3, or 4 µg/mL of VA for 24 h and then incubated in the absence or presence of DETA-NO (1,000 µmol/liter) and VA for an additional 6 h. The results showed that exposure to DETA alone decreased cell proliferation compared with the negative control. Pretreatment with VA promoted the proliferation of BMECs, increased the activities of antioxidative enzymes including selenoprotein glutathione peroxidase (GPx) and thioredoxin reductase (TrxR) and their gene and protein expression but decreased NO and interleukin 1 (IL-1) contents in a quadratic manner (P < 0.05). In addition, the expression of mRNA and protein of factors that are related to NF-κB or Nrf2 signaling pathways in BMECs were regulated by VA in a quadratic dose-dependent manner; VA at a concentration of 1 µµg/mL exhibited the strongest effect. Together, these results suggest that VA promotes antioxidant functions of BMECs by regulating the synthesis of selenoproteins including GPx and TrxR and by reducing concentrations of IL-1 and NO in vitro by modulating Nrf2 and NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

Prolonged consumption of Indigofera pasture plants can cause both hepatotoxicosis and reproductive losses in grazing animals with the responsible toxin indospicine forming persistent tissue residues. Separate accumulation and depletion feeding trials were undertaken in calves fed Indigofera spicata (3 mg indospicine/kg bodyweight) to ascertain the appearance and elimination of indospicine from various tissues. In the accumulation trial indospicine concentrations increased throughout the 42-day feeding period with maximum levels of 15 mg/L in plasma and 19 and 33 mg/kg in liver and muscle, respectively. In the depletion trial, calves were fed I. spicata for 35 days, after which the plant was withdrawn from the diet. The rate of elimination was relatively slow with estimates of half-life being 31, 25 and 20 days for muscle, liver and plasma, respectively. Indospicine levels measured in bovine tissues in this trial are comparable with levels in horsemeat and camel meat reported to cause fatal hepatoxicity in dogs, a species known to be susceptible to this toxin. The persistence of indospicine residues in bovine tissues and the widespread distribution of Indigofera species in tropical and sub-tropical grazing lands warrant further investigation, as indospicine has been established as causing reproductive losses and likely contributes to calf losses in these regions. [ABSTRACT FROM AUTHOR]

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The diverse rumen microbiome converts lowquality feedstuffs into usable energy and provides approximately 70% of the energy required by its ruminant host through fermentation byproducts. Due to microbial impacts on host health and productivity, numerous studies have associated rumen microbiome variation with important sustainability phenotypes, such as feed efficiency and methane emissions. Although diet, genetics, and environment contribute to variation in feed efficiency, selection for feed-efficient beef cattle using genetic improvement technologies has helped to understand and improve the persistence and longevity of such phenotypes within the herd. While diet has been considered to be the primary driver for the composition and structure of the rumen microbiome, recent studies have indicated the microbial communities present in the rumen are under low-to-moderate host genetic control. The mutualistic, commensal, and parasitic microorganisms that reside in the rumen and lower gastrointestinal tract of cattle and other ruminants exert enormous influence over animal physiology and performance. The ability to interrogate these systems at great depth has permitted a greater understanding of the microbiological and molecular mechanisms involved in ruminant nutrition and health. The work in our group in the field of beef cattle gut microbiology, as it relates to feed efficiency, permits the exploration of these critical microbial community networks. This knowledge will aid researchers seeking to address the grand challenge of maintaining host-efficient gut microbiomes throughout cattle production operations. This work is supported by the Agriculture and Food Research Initiative grant no. 2020-67015-30832 from the USDA National Institute of Food and Agriculture. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to investigate the effect of corn grain particle size on ruminant fermentation and blood metabolites in Holstein steers fed total mixed ration (TMR) as a basal diet to explain fundamental data of corn grain for cattle in Korea. Methods: Four ruminally cannulated Holstein steers (body weight 592±29.9 kg) fed TMR as a basal diet were housed individually in an auto temperature and humidity modulated chamber (24°C and 60% for 22 h/d). Treatments in a 4×4 Latin square design were TMR only (control), TMR with whole corn grain (WC), coarsely ground corn grain (CC), and finely ground corn grain (FC), respectively. The corn feeds substituted for 20% energy intake of TMR intake. To measure the ruminal pH, ammonia N, and volatile fatty acids (VFA), ruminal digesta was sampled through ruminal cannula at 1 h intervals after the morning feeding to determine ruminal fermentation characteristics. Blood was sampled via the jugular vein after the ruminal digesta sampling. Results: There was no difference in dry matter (DM) intake between different corn particle size because the DM intake was restricted to 1.66% of body weight. Different corn particle size did not change mean ammonia N and total VFA concentrations whereas lower (p<0.05) ruminal pH and a ratio of acetate to propionate, and higher (p<0.05) propionate concentration were noted when the steers consumed CC compared with WC and FC. Concentration of blood metabolites were not affected by different particle size of corn grain except for blood triglyceride concentration, which was significantly (p<0.05) increased by FC. Conclusion: Results indicate that feeding CC may increase feed digestion in the rumen, whereas the FC group seemed to obtain inadequate corn retention time for microbial degradation in the rumen. [ABSTRACT FROM AUTHOR]

The aim of this study was to measure different characteristics of the cow teats and teat canals using ultrasonographic scanning, discover morphological changes in cow teats and recovery time of the teat tissue caused by machine milking. Overall 148 dairy cows of the Holstein (n = 100) and Simmental (n = 48) breed were investigated. Recovery of the teat internal parameters after milking was observed by ultrasonographic scanning. Teat canal length (TCL), teat canal diameter (TCD) and teat wall thickness (TWT) of 296 right front and rear teat were evaluated from 1776 measurements before (t0) and 0, 30, 60, 90 and 120 minutes after milking (t1 - t5). Maximum significant differences for the selected teat characteristics were found between t0 and t1 measurements. The highest restorations of the initial length 103.52% and 114.23% were detected 120 minutes after milking for front and rear teat canals in Holstein breed. Similar process of restoration was found in Simmental breed. All measured internal traits (TCL, TCD, TWT) showed decrease of values indicating the regeneration process of the teat and udder structures after the milking. However, teat canal length a teat wall thickness remained extended until the examination, what proved that 120 minutes period is not enough time for teat structures full recovery after milking. Significant relationships before milking between front teat canal diameter and daily milk yield (r = 0.348) and milk flow rate (r = 0.257) were confirmed. Negative correlations were found between teat canal length (front and rear) and milk production and milk flow rate before milking and immediately after milking. Significant effect of breed and recovery time was found in all internal traits, whereas cross factors daily milk production, recovery time and milk flow rate recovery time were significantly influenced only in relation to teat canal diameter. [ABSTRACT FROM AUTHOR]