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The purpose of this study was to explore whether conjugated linoleic acid (CLA) could alleviate fatty liver hemorrhagic syndrome (FLHS) induced by estradiol benzoate intramuscular injection in laying hens. One hundred male Hy-Line white chickens were randomly divided into two groups, namely, the control (CON) and estradiol benzoate (E) groups, and both groups were fed the same basal diet. After injections of estradiol benzoate at 2 mg/kg every two days for a total of 7 times, chickens in the E group showed FLHS symptoms, including liver enlargement, hemorrhage, and steatosis. Then half of the chickens in the E group received an additional diet containing 5000 mg/kg CLA for 8 weeks. The results of morphological observations, hematoxylin and eosin staining, and Oil Red O staining showed that CLA alleviated liver enlargement, hemorrhage, and lipid accumulation in FLHS chickens. In addition, we measured liver function and lipid metabolism indicators, including ALT, AST, TG, TCH, HDL-C, and LDL-C, which further suggested that CLA mitigated the disturbance of serum and liver metabolism in FLHS chickens. Mechanistically, CLA inhibited hepatic de novo lipogenesis, cholesterol synthesis, and TG accumulation and increased TG hydrolysis in FLHS chickens by regulating the gene expression of CD36, ACC, FAS, SCD 1, DGAT2, LIPE, ATGL, CPT1A, SREBP-1c, SREBP-2, PPARγ, and PPARα. Furthermore, CLA ameliorated hepatic oxidative stress and inhibited NF-κB signaling pathway-mediated inflammation in FLHS chickens. In conclusion, CLA regulated lipid metabolism, thus further alleviating oxidative stress and inflammation to alleviate FLHS induced by estrogen in chickens.

The research direction of our team is nutrition and physiology of ruminants, including dietary nutrition metabolism and rumen microorganisms. Previous research has shown that ruminal acetate-to-propionate ratio is related to diet utilization efficiency. At present, it is believed that the main factors affecting the ruminal acetate-to-propionate ratio are the degradation rate of the diet and the rumen microbial structure, but the main mechanism is unclear. This study found that the effect of ruminal acetate-to-propionate ratio was not affected by the concentration of the fermentation substrate, but was affected by the structure of the rumen microbiota. We believe that changes in the rumen microflora structure are the main mechanism for regulating the ruminal acetate-to-propionate ratio. This will help people to further understand the rumen physiology, thereby gradually improving feed conversion efficiency and reducing production costs. Abstract: In order to explore the mechanism by which diet regulates the acetate-to-propionate molar ratio (A: P ratio), we compared the effect on rumen fermentation parameters and the microbiome by altering the ratio of dietary concentrates to roughage ratio and calcium pyruvate infusion. The test animals were Laoshan dairy goats, and were fed continuously through an automatic feeder. The test groups were fed a base diet of low concentrates, and intraruminally infused with calcium pyruvate at two concentrations. The infusion concentrations were derived from the difference in the rate of carbohydrate degradation of the high and low concentrate diets, and they were artificially set such that the high concentration infusion group was infused with twice the concentration as the low concentration infusion group. The control groups were fed high concentrate (6:4) and low concentrate (3:7) diets, respectively. The following results were obtained by measuring rumen fermentation parameters and microbial composition: the rumen A: P ratio was significantly lower in the high-concentrate diet group than in the low concentrate diet group (P 0.05), while infusion of high concentration calcium pyruvate significantly increased the rumen A: P ratio (P effect on rumen microbial structure. The above results indicate that increasing the concentration of the fermentation substrate without affecting the composition of the microflora does not reduce the A: P ratio. Microbiological results showed that the A: P ratio was more closely related to the rumen microflora structure. Therefore, it is believed that rumen microflora structure is the main mechanism regulating A: P ratio in rumen fermentation.

Objectives of this study were to investigate the effects of supplementing rumen-protected methionine (RP-Met), threonine (RP-Thr), isoleucine (RP-Ile), and leucine (RP-Leu) individually or jointly to a low-protein diet, on the performance of lactating dairy cows, as well as to determine the effects of these amino acids (AA) on the mammalian target of rapamycin (mTOR) in vivo. Ten lactating Holstein cows were randomly allocated to a repeated 5 × 5 Latin square experiment with five 19-d periods. Treatments were high-protein diet (16% crude protein, positive control; HP), low-protein diet (12% crude protein, negative control; LP), LP plus RP-Met (LPM), LP plus RP-Met and RP-Thr (LPMT), and LP plus RP-Met, RP-Thr, RP-Ile, and RP-Leu (LPMTIL). The dry matter intakes (DMI) of the LP, LPM, and LPMT diets were lower than that of the HP diet, whereas the DMI of the LPMTIL diet was intermediate between the HP diet and the other LP diets. Supplementing RP-Met to the LP diet increased the yields of milk and milk protein, increased the content of milk urea N, and tended to increase milk N efficiency. Co-supplementation of RP-Thr with RP-Met resulted in no further milk production increase. Co-supplementation of all 4 rumen-protected amino acids (RP-AA) increased milk and lactose yields to the level of the HP diet and tended to increase milk protein yield compared with the LPMT diet. We found no significant differences in the contents and yields of milk components between the LPMTIL and HP diets except for a lower milk urea N content in the LPMTIL diet. Venous concentrations of the measured AA were similar across the LP and LP diets supplemented with RP-AA. Relative to levels of the HP diet, LP diets had higher venous concentrations of Met and Gly and tended to have higher Phe concentration and lower concentrations of Val and BCAA. The LPMTIL diet had higher venous concentrations of Arg, Lys, Met, Phe, and Glu, and a lower Val concentration. Phosphorylation status of the measured mTOR components in LPM and LPMT treatments were similar to those in the LP treatment but phosphorylation status of mTOR and eIF4E-binding protein 1 (4eBP1) in LPMTIL treatment were higher. The phosphorylation rates of eukaryotic elongation factor 2 (eEF2) in the 4 LP and LP plus RP-AA diets were higher than that of the HP diet. Overall, results of the present study supported the concept that under the relatively short time of this experiment, supplementing RP-AA, which are believed to stimulate the mTOR signal pathway, can lead to increased milk protein yield. This increase appears to be due to increased DMI, greater mTOR signaling, and greater eEF2 activity.

To investigate the possible pathways of Met deficiency to depress milk protein synthesis, 4 lactating goats fitted with jugular vein, mammary vein, and carotid artery catheters and transonic blood flow detectors on the external pudic artery were used in a 4 × 4 Latin square experiment. Goats were fasted for 24 h followed by a 9-h intravenous infusion of an AA mixture plus glucose. Milk yield was recorded and samples were taken in h 2 to 8 of the infusion period, and mammary biopsy was performed in the last hour. Treatments were graded removal of Met from the infused AA mixture to achieve Met content in the infusate of 100 (complete), 60, 30, or 0% of that in casein. Graded Met removal decreased yield of milk, milk protein, and lactose linearly and tended to decrease yield of milk fat linearly. Milk protein yield decreased to 82, 78, and 69% that of complete mixture infusion, respectively, when the 60, 30, and 0% Met infusate was infused. Circulating Met decreased linearly with graded Met removal. Arterial and venous Met decreased to 36 and 23% that of complete mixture infusion, respectively, when all Met was removed out of the mixture. Concomitant with the decreased circulating concentration was a similar increase in mammary Met affinity as reflected by the linearly increased mammary Met clearance rate. The increased affinity plus the linearly increased mammary blood flow totally offset the negative effect of decreased circulating Met concentration on mammary Met uptake. The overall result was similar mammary Met uptakes across treatments ranging from 285.9 to 339.5 μmol/h. Mammary uptakes of the other AA measured were generally not affected by treatments except for a linearly decreased Thr uptake and a trend of linearly increased Glu uptake. Consistent with the behavior of an AA mainly catabolized in the liver and mainly used for protein synthesis in peripheral tissues, mammary uptake to milk output ratios of Met measured in the present study ranged from 1.25 to 1.49 and was not affected by treatments. For the other AA measured, the ratio of Thr was linearly decreased and that of Glu was linearly increased by graded Met removal. Graded Met removal linearly elevated circulating urea N and glucose concentrations, indicating enhanced whole-body catabolism of AA and hepatic gluconeogenesis. Treatments had no significant effects on circulating insulin, growth hormone, and the other hormones and metabolites measured. Phosphorylation status of eIF4E binding protein 1 tended to decrease linearly and that of p70S6k was linearly decreased by graded Met removal, indicating depressed signal in the intracellular mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. In conclusion, results of the present study indicated that the mTORC1 pathway and whole-body AA catabolism rather than mammary uptake appeared the drivers for changes in milk protein synthesis in response to varying Met supply.

The present study investigated the effects of dietary forage source (quality) and particle size on chewing activity, saliva secretion, and ruminal pH. Twelve multiparous lactating Holstein cows, four of which were ruminally cannulated, were used in a replicated 4 × 4 Latin square experimental design with a 2 × 2 factorial arrangement of treatments. Cows fed wild-rye hay diets had longer daily eating times than cows fed oaten hay diets. Treatments had no effect on ruminating time; therefore, resting time varied inversely to eating time. Neither the rate nor the amount of saliva secretion while eating, ruminating, or resting was affected by diet, resulting in similar total daily saliva secretions across treatments (231 L/day). Total volatile fatty acids (VFAs) in the ruminal fluid from animals fed oaten hay diets were higher than those from animals fed wild-rye hay diets; further, VFAs increased with decreasing forage particle size (FPS). Consistent with elevated VFA concentrations, reducing FPS and including oaten hay in the diet decreased mean ruminal pH and increased the daily time of ruminal pH under 5.8. Results of this study suggest that forage source and particle size affect ruminal pH might be via variations in VFA production rather than increased salivary recycling of buffering substrates.

The objectives of this study were to determine the effects of forage source (quality) and particle size on feed sorting, milk production and nutrient digestibility in lactating dairy cows. Twelve multiparous lactating Holstein cows were used in a replicated 4 × 4 Latin square experiment with a 2 × 2 factorial arrangement of treatments. Treatments were as follows: (a) feeding long oaten hay (OL), (b) feeding short oaten hay (OS), (c) feeding long wild-rye hay (WL) and (d) feeding short wild-rye hay (WS). The sorting activity of cows fed wild-rye hay diets was greater than that of cows fed oaten hay diets. Sorting activity decreased with reduced forage particle size (FPS) for wild-rye hay diets but was not affected for oaten hay diets. Cows fed oaten hay diets had a similar dry matter intake (DMI), but higher total tract nutrient digestibility, and hence higher milk yield than cows fed wild-rye hay diets. The increase in DMI as a result of reduced FPS was significant in cows fed wild-rye hay diets. Feed efficiency (4% fat-corrected milk (FCM)/DMI) decreased from 1.18 to 1.11 when FPS decreased, but was not affected by the forage source. The digestibility of DM, crude protein (CP) and organic matter (OM) in the total tract was decreased by a reduction in FPS for wild-rye hay diets, but was not affected for oaten hay diets. In conclusion, cows fed high-quality forage (oaten hay) had a lower sorting activity and higher production performance than those fed poor-quality forage (wild-rye hay). The optimal dietary FPS in lactating dairy cows should take the effect of forage source into account.

Menin, the protein encoded by the MEN1 gene, is abundantly expressed in the epithelial cells of mammary glands. Here, we found MEN1/menin expression slowly decreased with advancing lactation but increased by the end of lactation. It happened that the number of bovine mammary epithelial cells decreases since lactation, suggesting a role of menin in the control of mammary epithelial cell growth. Indeed, reduction of menin expression through MEN1-specific siRNA transfection in the bovine mammary epithelial cells caused cell growth arrest in G1/S phase. Decreased mRNA and protein expression of Cyclin D1 was observed upon MEN1 knockdown. Furthermore, menin was confirmed to physically bind to the promoter region of Cyclin D1 through a ChIP assay, indicating that menin plays a regulatory role in mammary epithelial cell cycle progression. Moreover, lower expression of MEN1/menin induced increased epithelial cell apoptosis and caused extracellular matrix remodeling by down-regulating its associated genes, such as DSG2 and KRT5, suggesting that menin’s role may also be involved in the control of cell–cell adhesion in normal mammary glands. Taken together, our data revealed an unknown molecular function of menin in epithelial cell proliferation, which may be important in the regulation of lactation behavior of mammary glands. Electronic supplementary material The online version of this article (10.1007/s10911-017-9385-8) contains supplementary material, which is available to authorized users.

Increasing dietary roughage level is a commonly used strategy to prevent subacute ruminal acidosis. We hypothesized that high-roughage diets could promote chewing activity, saliva secretion, and hence more alkaline to buffer rumen pH. To verify the hypothesis, 12 multiparous Holstein cows in mid lactation were randomly allocated to 4 treatments in a triplicated 4 × 4 Latin square experiment with one cow in each treatment surgically fitted with a ruminal cannula. Treatments were diets containing 40, 50, 60, or 70% of roughage on a DM basis. Increasing dietary roughage level decreased DM, CP, OM, starch, and NEL intake, increased ADF intake, and decreased milk yield linearly. Intake of NDF was quite stable across treatments and ranged from 7.8 to 8.1 kg/d per cow. Daily eating time increased linearly with increased roughage level. The increase in eating time was due to increased eating time per meal but not number of meals per day, which was stable and ranged from 8.3 to 8.5 meals per day across treatments. Increasing dietary roughage level had no effect on ruminating time (min/d), the number of ruminating periods (rumination periods per d), and chewing time per ruminating period (min/ruminating period). Ruminating time per kilogram of NDF intake and total chewing time per kilogram of ADF intake were similar across treatments (57.4 and 183.8 min/kg, respectively). Increasing dietary roughage level linearly increased daily total chewing time; linearly elevated the mean, maximum, and minimum ruminal pH; and linearly decreased total VFA concentration and molar proportion of propionate in ruminal fluid. Saliva secretion during eating was increased, the secretion during rumination was unaffected, but the secretion during resting tended to decrease with increased dietary roughage level. As a result, total saliva secretion was not affected by treatments. In conclusion, the results of the present study did not support the concept that high-roughage diets elevated ruminal pH through increased salivary recycling of buffering substrates.

Thirty healthy Holstein dairy cows in the dry period were randomly divided into three groups and fed diets with different net energy for lactation (group A: 1.2 Mcal/kg DM, group B: 1.3 Mcal/kg DM, and group C: 1.4 Mcal/kg DM) for 8 weeks prepartum. Thereafter, dairy cows were fed a diet of the same formulation (1.66 Mcal/kg DM) for 12 weeks postpartum. The effects of different dietary energy densities in the dry period on postpartum performance and metabolic parameters of dairy cows were observed. Milk yield was reduced by 14.5% in the low-energy diet group; however, there were no differences in milk composition between the three groups. Postpartum plasma β-hydroxybutyrate, non-esterified fatty acid, growth hormone, and glucagon levels were significantly decreased whereas leptin and neuropeptide levels were elevated in the low-energy diet group. Moreover, body fat mobilization was attenuated, and the decline in postpartum body condition was reduced in the low-energy diet group, thus effectively reducing the postpartum negative energy balance.

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.

To determine whether insulin exerts an effect on milk fat yield through the direct regulation of milk fat synthesis in the mammary gland, the hyperinsulinemic-euglycemic clamp procedure was performed in lactating goats in the present study. The effects of the hyperinsulinemic-euglycemic clamp on milk yield, milk composition, milk fatty acid yield and the expression levels of mRNAs of milk fat synthesis-related genes were examined. The results revealed that the hyperinsulinemiceuglycemic clamp had no significant effect on the milk yield, the milk protein yield, the yield and content of lactose or the yield and content of solids-not-fat (SNF) (P > 0.05). In contrast, the milk fat percentage and milk fat yield were decreased by 35.3% and 33.6%, respectively (P C16) and 5 fatty acids synthesized de novo in the mammary gland ( 0.05), including acetyl-coenzyme A carboxylase (ACC), fatty acid synthase (FAS), fatty acidbinding protein (FABP), lipoprotein lipase (LPL), stearoyl-CoA desaturase (SCD) and glycerol-3-phosphate acyltransferase (GPAT). However, the expression level of the SCD gene was significantly reduced during the post-procedure period (P

A water-soluble polysaccharide fraction extracted from the leaf of Ginkgo biloba was named GBLP. The protective effect of GBLP on nonalcoholic fatty liver disease (NAFLD) was observed and underlying mechanism was explored. Wistar male rats were randomly divided into five groups, namely, normal control group, model control group and GBLP groups (100, 200 and 400 mg/kg/d). A rat model of NAFLD was established in male Wistar rats by feeding with high-fat diet (HFD) for 8 weeks. On day 57, the intragastric administration of GBLP started once daily for 4 weeks. The results showed that GBLP supplementation significantly and dose-dependently lowered the weight gain of body, liver index and serum lipid parameters in HFD-fed rat. Meanwhile, GBLP attenuated HFD-induced liver injury through reducing hepatic steatosis, TG accumulation, serum ALT, AST and ALP levels. GBLP had a positive effect on obesity-associated insulin resistance (IR) via reducing serum glucose and insulin levels. Furthermore, GBLP enhanced the activities of antioxidant enzymes and reduced MDA levels in serum and liver. These results indicate that GBLP can play a certain protective role against HFD-induced NAFLD, and the protective effects may be associated with attenuating IR, preserving liver function, enhancing antioxidant defense system, and reducing lipid peroxidation.

The MEN1 gene, which encodes the protein Menin, was investigated for its regulatory role in milk protein synthesis in mammary glands. Menin responds to nutrient and hormone levels via the PI3K/Akt/mTOR pathway. Bovine mammary epithelial cells and tissues were used as experimental models in this study. The results revealed that the milk protein synthesis capacity of mammary epithelial cells could be regulated by MEN1/Menin. The overexpression of Menin caused significant suppression of factors involved in the mTOR pathway, as well as milk protein κ-casein (CSNK). In contrast, a significant increase in these factors and CSNK was observed upon MEN1/Menin knockdown. The repression of MEN1/Menin on the mTOR pathway was also observed in mammary gland tissues. Additionally, MEN1/Menin was found to elicit a negative response on prolactin (PRL) and/or insulin (INS), which caused a similar downstream impact on mTOR pathway factors and milk proteins. Collectively, our data indicate that MEN1/Menin could play a regulatory role in milk protein synthesis through mTOR signaling in the mammary gland by mediating the effects of hormones and nutrient status. The discovery of Menin’s role in mammary glands suggests Menin could be potential new target for the improvement of milk performance and adjustment of lactation period of dairy cows.

This study was conducted to evaluate the effect of aloe polysaccharide on immune responses of chickens immunized with Bordetella avium ( B. avium ) vaccine. SPF chickens were randomly divided into 6 groups and vaccinated against B. avium vaccine which respectively contained aloe polysaccharide of three different dosages, propolis and pine pollen polysaccharide. The data showed that aloe polysaccharide significantly enhanced serum and bile antibody level, blood lymphocyte ratio and splenic T lymphocyte proliferation rate in groups I, IV and V. 40 mg/ml of aloe polysaccharide made the vaccine most effective and 20 mg/ml of propolis or 20 mg/ml of pine pollen polysaccharide achieved the same effect. These results suggested that aloe polysaccharide could significantly enhance immune effect of B. avium inactivated vaccine and had important implications for the further use of aloe polysaccharide as a new type of plant-derived immunopotentiator.

Varied doses of Taishan Pinus massoniana pollen polysaccharide (TPPPS) and Astragalus polysaccharide (APS) extracted by hot water extraction and ethanol precipitation method were added to the vaccine in order to prepare polysaccharide-rabbit haemorrhagic disease (RHD) tissue inactivated vaccine. The purpose was to study effects of TPPPS on immune response of RHD tissue inactivated vaccine and on production performance of Rex rabbits. Results showed that each index in groups I, II, III and IV was higher than that in group V, especially groups I, II and IV, the difference between which and group V was much more significant (P

Sixteen shorthorn cows from Xiazhuang farm were admitted to the Veterinary Teaching Hospital at the College of Animal Science and Veterinary Medicine, Shandong Agricultural University for evaluation of poor appetite, listlessness, fever, tachycardia, tachypnea, lethargy, positive jugular venous pulse and anemia. Blood smear examination and polymerase chain reaction analysis in these cows revealed an infection with Mycoplasma wenyonii. The subjects were divided into two groups: control group (three cows) treated with intramuscular injection with imidocarb dipropionate (3 mg/kg/day for 2 days) and the experimental group (13 cows), treated with injection-acupuncture (Imidocarb Dipropionate, 1 mg/kg, once every 3 days for 6 days) at BL17, BL18, BL20, BL25, ST36, SP06 and CV04. At day 15, negative results were found using blood smear examination in all control and experimental groups.

Bordetellosis, caused by Bordetella avium, continues to be an economic problem in the poultry industry of China. Vaccines with good protective ability are lacking. Thus, developing a novel vaccine against the B. avium infection is crucial. Here, we constructed a recombinant Pichia pastoris transformant capable of expressing the outer membrane protein A (ompA) of B. avium to prepare the recombinant ompA subunit vaccine and then evaluated its immune effects. To further investigate the immunomodulation effects of Taishan Pinus massoniana pollen polysaccharides (TPPPS) on this subunit vaccine, three concentrations (20, 40, and 60 mg/mL) of TPPPS were used as the adjuvants of the ompA subunit vaccine respectively. The conventional Freund's incomplete adjuvant served as the control of TPPPS. Chickens in different groups were separately vaccinated with these vaccines thrice. During the monitoring period, serum antibody titers, concentrations of serum IL-4, percentages of CD4(+) and CD8(+) T-lymphocytes in the peripheral blood, lymphocyte transformation rate, and protection rate were detected. Results showed that the pure ompA vaccine induced the production of anti-ompA antibody, the secretion of IL-4, the increase of CD4(+) T-lymphocytes counts and lymphocyte transformation rate in the peripheral blood. Moreover, the pure ompA vaccine provided a protection rate of 71.67% after the B. avium challenge. Notably, TPPPS adjuvant vaccines induced higher levels of immune responses than the pure ompA vaccine, and 60 mg/mL TPPPS adjuvant vaccine showed optimal immune effects and had a 91.67% protection rate. Our findings indicated that this recombinant B. avium ompA subunit vaccine combined with TPPPS had high immunostimulatory potential. Results provided a new perspective for B. avium subunit vaccine research.

Dermonecrotic toxin (DNT) produced by Bordetella bronchiseptica (B. bronchiseptica) can cause clinical turbinate atrophy in swine and induce dermonecrotic lesions in model mice. We know that the N-terminal of DNT molecule contains the receptor-binding domain, which facilitates binding to the target cells. However, we do not know whether this domain has sufficient immunogenicity to resist B. bronchiseptica damage and thereby to develop a subunit vaccine for the swine industry. In this study, we prokaryotically expressed the recombinant N-terminal of DNT from B. bronchiseptica (named DNT-N) and prepared it for the subunit vaccine to evaluate its immunogenicity. Taishan Pinus massoniana pollen polysaccharide (TPPPS), a known immunomodulator, was used as the adjuvant to examine its immune-conditioning effects. At 49 d after inoculation, 10 mice from each group were challenged with B. bronchiseptica, and another 10 mice were intradermally challenged with native DNT, to examine the protection imparted by the vaccines. The immune parameters (T-lymphocyte counts, cytokine secretions, serum antibody titers, and survival rates) and skin lesions were determined. The results showed that pure DNT-N vaccine significantly induced immune responses and had limited ability to resist the B. bronchiseptica and DNT challenge, whereas the mice administered with TPPPS or Freund's incomplete adjuvant vaccine could induce higher levels of the above immune parameters. Remarkably, the DNT-N vaccine combined with TPPPS adjuvant protected the mice effectively to prevent B. bronchiseptica infection. Our findings indicated that DNT-N has potential for development as an effective subunit vaccine to counteract the damage of B. bronchiseptica infection, especially when used conjointly with TPPPS.

This study evaluated the immune-enhancing activity of polysaccharides from the rhizoma of Atractylodis macrocephalae Koidz (RAMPS) in vitro. Lymphocyte proliferation, cell cycle distribution, and percentages of CD4(+) and CD8(+) cells were determined. Different concentrations of RAMPS were added to peripheral blood T lymphocytes. Results showed that RAMPStp and RAMPS60c could significantly enhance T lymphocyte proliferation individually or synergistically with phytohemagglutinin at most concentrations. The active sites of RAMPStp and RAMPS60c were then selected. Lymphocyte cell cycle distribution and percentages of CD4(+) and CD8(+) cells were determined by flow cytometry. At most time points, RAMPS60c and RAMPStp could promote lymphocytes enter into S and G2/M phases. RAMPStp and RAMPS60c effectively improved the percentages of CD4(+) and CD8(+) T cells. RAMPStp produced optimal effects. Therefore, RAMPStp could be used as a component of novel immunopotentiators.

To determine the effects of the initial timing of forage supply on growth, ruminal fermentation parameters and rumen development in preweaning calves, 18 7-day-old Holstein calves of 42 ± 3 kg were randomly divided into three treatment groups. The dietary treatments were (1) milk and commercial starter diet (MS) control, (2) milk and starter diet supplemented with oat hay at 2 weeks (MSO2), and (3) milk and starter diet supplemented with oat hay at 6 weeks (MSO6). Starter feed and oat hay were provided ad libitum, and 2 L of milk was provided twice daily. Samples were collected at 64 days of age. Supplementing with hay increased the dry-matter intake; P < 0.05). The height, body length, heart girth and cannon bone circumference were similar among the three treatments (P > 0.05). The concentrations of serum glucose (P = 0.07) and β-hydroxybutyric acid; P < 0.05) were lower in the MSO6 group than in the MS and MSO2 groups. Rumination time was longer, and time spent on non-nutritive oral behaviour (such as e.g. licking surfaces, tongue rolling, wood-shaving consumption) was lower for hay-supplemented calves than for the control (P < 0.05). Although ruminal pH of hay-supplemented calves was significantly higher than that of the control, total rumen fluid volatile fatty acid concentrations were not significantly different among treatments. Calves in the MSO2 group had a smaller ratio of empty weight to slaughter weight (P < 0.05) and a larger total digestive tract weight (P < 0.05); the empty gastrointestinal tract weights were similar among the three treatments, suggesting that MSO2 calf weight gain may have resulted from intestinal chyme accumulation. Compared with the control, hay-supplemented calves had reduced rumen papilla width and epithelium thickness (P < 0.05), and no discernable plaque formation. Hay supplementation in the diet of preweaning calves improved the overall dry-matter intake, improved rumination, reduced non-nutritive oral behaviours, improved rumen pH, and ensured healthy rumen development; furthermore, productivity and rumen development were better in calves supplemented with hay from the second week.

An animal feeding trial was conducted on 18 seven‐day‐old Holstein dairy bull calves weighing 42 ± 3 kg each. Calves were randomly assigned into three groups (n = 6 each). The dietary treatments were as follows: (1) milk and starter for the control group (MS), (2) supplementation of oat hay from week 2 on the basis of milk and starter (MSO2), and (3) supplementation of oat hay from week 6 on the basis of milk and starter (MSO6). All animals were fed starter and oat hay ad libitum. The major phyla in the different groups of rumen fluid included Firmicutes, Actinobacteria, Bacteroidetes, Proteobacteria, and Euryarchaeota. The major genera were identified, and major genera proportions in the three groups were as follows: Methanobrevibacter (Euryarchaeota), 2.1%, 1.7%, and 2.1%; Olsenella (Actinobacteria), 23.9%, 17.7%, and 12.8%; Prevotella (Bacteroidetes), 10.5%, 16.5%, and 19.2%; Dialister (Firmicutes), 3.3%, 4.1%, and 2.8%; Succiniclasticum (Firmicutes), 3.8%, 4.7%, and 9.2%; and Sharpea (Firmicutes), 0.4%, 2.5%, and 0.2%, respectively. There were no significant differences in the various phyla among the three groups (p > .05). The results showed that calves hay supplementation time did not affect the diversity of the rumen microbiota in the suckling calves. However, the hay supplementation altered the proportion of the various microbial populations, supplementation of oat hay from week 2 on the basis of milk and starter could improve calves rumen pH.

Mycoplasma suis (M. suis), a hemotrophic pathogen of pigs, causes economic losses in swine production throughout the world. Inorganic pyrophosphatase (ppa) is a very important gene in M. suis. The ppa gene of M. suis was synthesized by PCR-based accurate synthesis (PAS) and overlapextension PCR, inserted into vector pMD18-T, and then subcloned to the prokaryotic expression vector pET28c.The recombinant plasmid pET28c_ppa was transformed to E. coli BL21 for expression under induction of isopropyl thiogalactoside. The expressed product was identified by SDS-PAGE and Western blot, which suggested that the recombinant protein has good antigenicity. Piglets were immunised with purified recombinant protein, and specific antibodies to the recombinant protein were detected in piglet serum. The results show that the ppa gene can be efficiently expressed in E. coli and that the expressed recombinant protein can elicit a specific serum antibody response in piglets. PAS and overlap-extension PCR were first used to synthesize the ppa of M. suis. They provide simple, rapid, reliable and relatively inexpensive methods to synthesize, clone, and express genes. The experiment conducted in this paper will enable future research into the role and function of the ppa gene.

Multiparous early lactation Holstein cows (n = 16) were used in a randomized complete block design to determine the effects of feeding fatty acid calcium and the interaction of forage quality on production performance and biochemical indexes in early lactation cow. Treatments were as follows: (i) feeding low-quality forage without supplying fatty acid calcium (Diet A), (ii) feeding low-quality forage with supplying 400 g fatty acid calcium (Diet B), (iii) feeding high-quality forage without supplying fatty acid calcium (Diet C) and (iv) feeding high-quality forage with supplying 400 g fatty acid calcium. This experiment consisted 30 days. The milk and blood samples were collected in the last day of the trail. Intakes were recorded in the last 2 days of the trail. Supplementation of fatty acid calcium decreased significantly dry matter intake (DMI) (p < 0.01). Addition fatty acid calcium decreased milk protein percentage (p < 0.01) and milk SNF percentage (p < 0.01), but increased MUN (p < 0.05). Supplemented fatty acid decreased concentration of blood BHBA (p < 0.05), but increased TG, NEFA, glucagon, GLP-1, CCK, leptin, ApoA-IV, serotonin and MSH concentration in blood, the CCK concentration and feed intake showed a significant negative correlation (p < 0.05).

Background Lactogenesis includes two stages. Stage I begins a few weeks before parturition. Stage II is initiated around the time of parturition and extends for several days afterwards. Methodology/Principal Findings To better understand the molecular events underlying these changes, genome-wide gene expression profiling was conducted using digital gene expression (DGE) on bovine mammary tissue at three time points (on approximately day 35 before parturition (−35 d), day 7 before parturition (−7 d) and day 3 after parturition (+3 d)). Approximately 6.2 million (M), 5.8 million (M) and 6.1 million (M) 21-nt cDNA tags were sequenced in the three cDNA libraries (−35 d, −7 d and +3 d), respectively. After aligning to the reference sequences, the three cDNA libraries included 8,662, 8,363 and 8,359 genes, respectively. With a fold change cutoff criteria of ≥2 or ≤−2 and a false discovery rate (FDR) of ≤0.001, a total of 812 genes were significantly differentially expressed at −7 d compared with −35 d (stage I). Gene ontology analysis showed that those significantly differentially expressed genes were mainly associated with cell cycle, lipid metabolism, immune response and biological adhesion. A total of 1,189 genes were significantly differentially expressed at +3 d compared with −7 d (stage II), and these genes were mainly associated with the immune response and cell cycle. Moreover, there were 1,672 genes significantly differentially expressed at +3 d compared with −35 d. Gene ontology analysis showed that the main differentially expressed genes were those associated with metabolic processes. Conclusions The results suggest that the mammary gland begins to lactate not only by a gain of function but also by a broad suppression of function to effectively push most of the cell's resources towards lactation.