Microbiome-transcriptome analysis reveals that dietary supplementation with macleaya cordata extract alters multiple immune pathways with minimal impact on microbial structure.

Background: As a potential antibiotic alternative, macleaya cordata extract (MCE) has anti-inflammatory, antioxidant, and antimicrobial properties. This study was conducted to assess the impact of MCE supplementation on the gut microbiota and its interplay with the host in young goats. Thirty female black goats with similar body weight (5.63 ± 0.30 kg) were selected and randomly allotted into one of three diets: a control diet (Control), a control diet with antibiotics (Antibiotics, 21 mg/kg/day vancomycin and 42 mg/kg/day neomycin), and a control diet with MCE (MCE, 3.75% w/w premix). Results: Principal coordinate analysis of the microbial community showed that samples of Antibiotic clustered separately from both Control and MCE (p < 0.001). The random forest analysis revealed that, in comparison to the Control group, the impact of Antibiotics on the microbiota structure was more pronounced than that of MCE (number of featured microbiota, 13 in Antibiotics and >6 in MCE). In addition, the pathways of significant enrichment either from DEGs between Antibiotics and Control or from DEGs between MCE and Control were almost identical, including Th17 cell differentiation, butanoate metabolism, T-cell receptor signaling pathway, intestinal immune network for IgA production, antigen processing and presentation, and ABC transporters. Furthermore, an integrative analysis indicated that significant positive correlations (p < 0.05) were observed between HEPHL1 and the featured biomarkers Atopostipes, Syntrophococcus, Romboutsia, and Acinetobacter in the MCE group. Conversely, several significant negative correlations (p < 0.05) were identified between HEPHL1 and the featured biomarkers Clostridium_XlVa, Phascolarctobacterium, Desulfovibrio, Cloacibacillus, Barnesiella, Succinatimonas, Alistipes, Oscillibacter, Ruminococcus2, and Megasphaera in the Antibiotics group. Conclusion: Collectively, the analysis of microbiome-transcriptome data revealed that dietary supplementation with MCE produced significant alterations in multiple immune pathways, while having minimal impact on the microbial structure.

Effects of organic and inorganic selenium on selenium bioavailability, growth performance, antioxidant status and meat quality of a local beef cattle in China.

Selenium (Se) is an essential nutrient with multiple health benefits to humans and animals. Cattle generally require dietary Se supplementation to meet their daily requirements. The two main forms of dietary Se in cattle are organic Se and inorganic Se. Data comparing the health and productivity effects of organic Se and inorganic Se on cattle are still insufficient, and it is necessary to conduct more research to evaluate the bioavailability, nutritional value, deposition, and body functions of Se sources in different breeds and physiological stages of cattle raised in areas with different Se levels. The objectives of this study were to determine the effects of organic and inorganic sources of Se on plasma biochemical indices, Se bioavailability, deposition in body tissues and organs, growth performance, antioxidant capacity and meat quality of beef cattle raised in Se-deficient areas. Fifteen Chinese Xiangzhong Black beef cattle with an average weight of 254.5 ± 8.85 kg were assigned to three dietary groups. The three groups were fed the same basal ration and supplemented with either an inorganic [sodium selenite (SS)] or organic [selenomethionine (SM) or Se-enriched yeast (SY)] source of Se (0.1 mg/kg dry matter) for 60 days. At the end of the experiment, three cattle from each group were randomly selected and slaughtered, and samples were collected from tissues and organs for analysis. The results revealed that growth performance, slaughter performance, Se content of tissues and organs, meat quality characteristics including chemical composition, pH45min, pH24h, drip loss, and cooking losses did not differ (p > 0.05) due to supplementation of the different organic and inorganic sources of Se. SM and SY were more effective in increasing (p < 0.05) immunoglobulin M (IgM) concentrations in the blood and reducing (p < 0.05) malondialdehyde (MDA) content in the longissimus dorsi than SS. In conclusion, organic Se is more effective than inorganic Se in improving the immune and antioxidant capacity of Chinese Xiangzhong Black beef cattle.

Rumen-protected glucose stimulates the secretion of reproductive hormones and the mTOR/AKT signaling pathway in the ovaries of early postpartum.

This study was conducted to determine the response of the reproductive hormones and the mTOR/AKT/PI3K pathway in the ovaries of postpartum dairy cows with dietary rumen-protected glucose (RPG). Twelve Holstein cows were randomly assigned to two groups (n = 6/group): the control group (CT) and the RPG group. Blood samples were collected on d 1, 7, and 14 after calving for the gonadal hormone assay. The expression of the gonadal hormones receptors and PI3K/mTOR/AKT pathways were detected using RT-PCR and Western blot. The RPG addition increased the plasma LH, E2, and P4 concentrations on d 14 after calving and upregulated the mRNA and protein expressions of the ERα, ERß, 17ß-HSD, FSHR, LHR, and CYP17A1 but downregulated StAR expression. Immunohistochemical analysis identified higher expressions of the FSHR and LHR in the ovaries of RPG-fed cows compared to CT cows. Furthermore, the protein expressions of p-AKT/AKT and p-mTOR/mTOR were significantly increased in the ovaries of RPG-fed cows compared to the CT group, but the addition of RPG did not alter the protein expression of p-PI3K/PI3K. In conclusion, the current results indicated that dietary RPG supplementation regulated gonadotropin secretion and stimulated expression of hormone receptors and the mTOR/AKT pathway in the ovaries of early postpartum dairy cows. RPG may be beneficial for the recovery of ovarian activity in post-calving dairy cows.

Replacing ZnSO4 with Zn-glycine in the diet of goat promotes the pancreatic function of the offspring.

Zinc supplementation in the diet of goats affects pancreas development in offspring. However, the impact of maternal inorganic and organic zinc supplementation in offspring is poorly defined. In this study, 14 late-pregnant goats were assigned at random to the zinc sulfate group (ZnSO4, n = 7) and the zinc-glycine chelate group (Zn-Gly, n = 7), respectively. Serum samples and pancreas tissue were collected from kids whose mothers were fed ZnSO4 and Zn-Gly at the late pregnancy, respectively. Histologic examination showed no morphologic differences between the 2 groups. Pancreatic zinc content in kids tended to be increased when replacing ZnSO4 with Zn-Gly. The serum insulin concentration was greater and glucagon less in the Zn-Gly group when compared to the ZnSO4 group. The activities of lipase and chymotrypsin were enhanced when replacing ZnSO4 with Zn-Gly. Proteomics results showed that 234 proteins were differentially expressed between the 2 groups, some of which were associated with the secretion of insulin, enzyme activity and signal transduction. The results suggested that supply of dietary Zn-Gly to goats during late pregnancy promoted pancreatic function in offspring compared with dietary ZnSO4 supplementation. This provides new information about pancreatic function when supplementing different zinc sources in the diets of late pregnant goats.

The ileal microbiome and mucosal immune profiles in response to dietary supplementation of ultra-grinded Astragalus membranaceus in weaned goats.

Weaning goats are susceptible to diarrhea and have weakened immune functions due to physiological, dietary and environmental stresses. Astragalus membranaceus (A. membranaceus), a traditional Chinese medicinal herb, has been shown to improve growth performance and immunity in weaned ruminants. However, the influence mechanism of A. membranaceus on intestinal microbiota and mucosal immunity in weaned goats is still unknown. This study investigated the effects of ultra-grinded A. membranaceus (UGAM) on the immune function and microbial community in the ileum of weaned goats. Eighteen healthy weaned Xiangdong black goats (BW, 5.30 ± 1.388 kg) were used in a study of completely randomized block design with 28 days long. The animals were randomly assigned to either a basal diet supplemented with 10 g/d of milk replacer (CON, n = 9) or the CON diet supplemented with 10 g/head UGAM (UGAM, n = 9). Supplementation of UGAM increased (p < 0.05) the plasma concentrations of total protein and albumin. Meanwhile, the addition of UGAM reduced (p < 0.05) the relative mRNA expression of the IL-6 gene (a marker of inflammation), indicating the potential immunomodulatory effect of UGAM. Moreover, the relative abundances of Verrucomicrobiota and Mycoplasma were lower (p < 0.05) in the ileum of goats supplemented with UGAM than CON. These findings suggest that dietary supplementation of UGAM may have enhanced the ileum health of weaned goats by reducing inflammation factor expression and reducing the relative abundance of pathogenic microbes. The observed beneficial effects of ultra-grinded A. membranaceus on ileal mucosal immune and the community of ileal microbiota indicate its potential to be used as a viable option for promoting the well-being of weaned goats under weaning stress.

Lipid metabolism and m6A RNA methylation are altered in lambs supplemented rumen-protected methionine and lysine in a low-protein diet.

BACKGROUND: Methionine or lysine has been reported to influence DNA methylation and fat metabolism, but their combined effects in N6-methyl-adenosine (m6A) RNA methylation remain unclarified. The combined effects of rumen-protected methionine and lysine (RML) in a low-protein (LP) diet on lipid metabolism, m6A RNA methylation, and fatty acid (FA) profiles in the liver and muscle of lambs were investigated. Sixty-three male lambs were divided into three treatment groups, three pens per group and seven lambs per pen. The lambs were fed a 14.5% crude protein (CP) diet (adequate protein [NP]), 12.5% CP diet (LP), and a LP diet plus RML (LP + RML) for 60 d. RESULTS: The results showed that the addition of RML in a LP diet tended to lower the concentrations of plasma leptin (P = 0.07), triglyceride (P = 0.05), and non-esterified FA (P = 0.08). Feeding a LP diet increased the enzyme activity or mRNA expression of lipogenic enzymes and decreased lipolytic enzymes compared with the NP diet. This effect was reversed by supplementation of RML with a LP diet. The inclusion of RML in a LP diet affected the polyunsaturated fatty acids (PUFA), n-3 PUFA, and n-6 PUFA in the liver but not in the muscle, which might be linked with altered expression of FA desaturase-1 (FADS1) and acetyl-CoA carboxylase (ACC). A LP diet supplemented with RML increased (P < 0.05) total m6A levels in the liver and muscle and were accompanied by decreased expression of fat mass and obesity-associated protein (FTO) and alkB homologue 5 (ALKBH5). The mRNA expressions of methyltransferase-like 3 (METTL3) and methyltransferase-like 14 (METTL14) in the LP + RML diet group were lower than those in the other two groups. Supplementation of RML with a LP diet affected only liver YTH domain family (YTHDF2) proteins (P < 0.05) and muscle YTHDF3 (P = 0.09), which can be explained by limited m6A-binding proteins that were mediated in mRNA fate. CONCLUSIONS: Our findings showed that the inclusion of RML in a LP diet could alter fat deposition through modulations of lipogenesis and lipolysis in the liver and muscle. These changes in fat metabolism may be associated with the modification of m6A RNA methylation. A systematic graph illustrates the mechanism of dietary methionine and lysine influence on lipid metabolism and M6A. The green arrow with triangular heads indicates as activation and brown-wine arrows with flat heads indicates as suppression.

Diet Supplementation With Sulfur Amino Acids Modulated Fermentation Metabolome and Gut Microbiome in Goats.

Dietary amino acids shift hydrogen metabolism to an alternative hydrogen sink consisting of dissolved hydrogen sulfur (dH2S) rather than methanogenesis; and influences the fermentation metabolome and microbiome associated with particles and liquid fractions in gut regions (foregut, small intestine, and hindgut) of goats. A completely randomized block design with a total of 20 goats (5 goats per treatment) was used to conduct the trial. The goats were fed on a diet that consisted of a concentrated mixture with maize stover roughage (50:50, on a dry matter basis) and randomly assigned to one of the four treatments: without amino acid supplementation (a basal diet), a basal diet supplemented with methionine (Met), a basal diet supplemented with lysine (Lys), and a basal diet supplemented with methionine and lysine (ML). Goats fed Met alone or in combination had less acetate, acetate to propionate ratio, and greater propionate (p < 0.05) in the foregut and hindgut than those fed control or Lys. Nonetheless, the goats fed on the amino acid supplements had higher levels of branched-chain VFA (p < 0.05) in the foregut and hindgut than the control goats. Goats fed on ML had the highest ammonia (p < 0.01), followed by Met or Lys, both in the foregut and hindgut, compared with the control. Those fed on Met alone or in combination, had lower dH2, dCH4 (p < 0.01), and higher dH2S (p < 0.01) in the foregut and hindgut than the control or Lys. The goats that were fed on Met alone or in combination, had higher 16S rRNA gene copies of total bacteria, methanogens, and 18S rRNA gene copies of protozoa, fungi, and fiber-utilizing bacterial species (p < 0.01) associated with particles vs. liquid, both in the foregut and hindgut than the control goats. This study gives insights into the use of sulfur-containing amino acids, as an alternative dietary mitigation strategy of methanogenesis in ruminants and highlights the need for further research in this direction.

Low-protein diets supplemented with methionine and lysine alter the gut microbiota composition and improve the immune status of growing lambs.

Feeding low-protein (LP) diets with essential amino acids could be an effective strategy for ruminants from economic, health and environmental perspectives. This study was conducted to investigate the effects of rumen-protected methionine and lysine (RML) in the LP diet on growth performance, innate immunity, and gut health of growing lambs. After 15 days of adaption, sixty-three male Hulunbuir lambs aged approximately 4 months were allotted to three dietary groups and each group had three pens with seven lambs for 60 days. The dietary treatments were as follows: a normal protein diet (14.5% CP, positive control; NP), LP diet (12.5% CP, negative control; LP), and LP diet with RML (12.5% CP, LP + RML). Lambs fed with LP + RML diet showed improved villus architecture and gut barrier function than those fed with the other two diets. The mRNA expressions of interleukin-1ß, tumor necrosis factor-α, interferon-γ, toll-like receptor-4, and myeloid differentiation primary response 88 were downregulated in most regions of the intestinal segments by feeding the LP + RML diet. Compared with the NP diet, feeding lambs with the LP diet increased the abundance of Candidatus_Saccharimonas in all regions of the intestinal tract and reversed by feeding the LP + RML diet. Lambs in the LP + RML diet group had lower abundance of Erysipelotrichaceae_UCG-009 and Clostridium_sensu_stricto_1 than those in the LP diet group. The results showed that supplementing RML in the LP diet exhibited beneficial effects on host immune function, intestinal mucosal integrity, and microbiota composition. KEY POINTS: • Adding methionine and lysine in a low-protein diet improve the intestinal mucosal growth and integrity. • Feeding a low-protein diet with methionine and lysine enhance the innate immune status. • Adding methionine and lysine in a low-protein diet alter the intestinal microbiota composition.

Effects of the natural sweetener rebaudioside A on intake, nutrient digestion, rumen fermentation, and blood biochemical parameters in adult goats during summer.

The effects of dietary rebaudioside A inclusion on feed intake, digestion of nutrients, rumen fermentation, and blood biochemical parameters of goats were evaluated in a replicated 3 × 3 Latin square study. Nine adult goats during summer were fed a basal forage/concentrate-based diet and the forage was chopped rice straw. The three dietary treatments were 0, 350, and 700 mg rebaudioside A per kg chopped rice straw on a DM basis. No significant improvement was observed in dry matter intake (DMI) of forage and diet among treatments. Nutrient digestibility of DM and organic matter (OM) showed a significant trend (p < .10) across groups. Rebaudioside A inclusion significantly (p < .01) increased the concentration of total volatile fatty acids in the rumen, however, there were no differences in concentration of ruminal ammonia, and molar proportions of acetate, propionate, and butyrate. About blood metabolites, increasing rebaudioside A in the diet caused a quadratic response in glucose and total protein, and albumin concentrations. Under the conditions of this study, supplementation with rebaudioside A at 350 and 700 mg/kg forage did not improve consumption of rice straw-based diet in adult goats in summer. However, the responses in digestibility, rumen fermentation, and blood metabolites appear to indicate the potential of rebaudioside A as a bio-active substance in goats.

Effects of Dietary Zinc-Methionine Supplementation During Pregnancy on the Whole-Genome Methylation and Related Gene Expression in the Liver and Spleen of Growing Goats: a Short Communication.

The effect of replacing inorganic zinc with organic zinc in diets of pregnant goats was investigated on the development of the liver and spleen of offspring. Pregnant goats (n = 14; Xiangdong black goat, local breed) of similar parity and body weight (BW, 37.17 ± 5.28 kg) were selected and divided randomly into two groups: the zinc sulfate group (ZnSO4; n = 7) and the methionine-chelated zinc group (Zn-Met; n = 7). Goats were fed for 45 days (day 106 of gestation to delivery). After delivering, lactating goats were fed a diet without extra zinc supplement. Kid goats were weaned at 2 months of age and both the groups were fed the same diet. All goats were fed a mixed diet and had free access to fresh water. Kid goats were slaughtered on day 100, and the liver and spleen were collected, weighed, and stored in liquid nitrogen for genomic DNA methylation and related gene expression determination. In the Zn-Met group, the liver organ index of kid goats showed an increasing trend (P < 0.10), but the methylation of the whole genome was not affected both in the liver and spleen (P > 0.10). Furthermore, the blood zinc content of the offspring was reduced (P < 0.05), and the expression of genes related to methylation were downregulated (P < 0.05) or showed a downward trend (P < 0.10) in the liver and spleen. These data indicated that goats feeding Zn-Met during pregnancy increased the offspring liver organ index without change in the genomic DNA methylation. It is speculated that the regulation of zinc finger protein Sp3 adjusted by blood zinc indirectly regulated the expression of methylation-related genes in the liver and spleen of the kid goats, thus enhancing the development and function of the immune system of the offspring.

Dietary xylo-oligosaccharide improves intestinal functions in weaned piglets.

This study aimed at investigating the effects of dietary xylo-oligosaccharide (XOS) on intestinal functions (i.e., intestinal morphology, tight junctions, gut microbiota and metabolism) and growth performance in weaned piglets. 19 weaned piglets were randomly divided into two groups (n = 9/10): a control group (basic diet) and a XOS treated group in which piglets were fed 0.01% XOS for 28 days. Growth performance, blood cells and biochemical parameters, serum cytokines, intestinal morphology, tight junctions, gut microbiota, and the metabolic profiles of the gut digesta were analyzed. The results showed that dietary supplementation with XOS had little effects on growth performance, blood cells and biochemical parameters, and intestinal morphology. However, the inflammatory status and intestinal barrier were improved in XOS-fed piglets evidenced by the reduction of IFN-γ and upregulation of ZO-1. Microbiota analysis showed that XOS enhanced α-diversity and affected the relative abundances of Lactobacillus, Streptococcus, and Turicibacter at the genus level. The alterations in the microbiota might be further involved in carbohydrate metabolism, cell motility, cellular processes and signaling, lipid metabolism, and metabolism of other amino acids by functional prediction. A metabolomics study identified three differentiated metabolites, including coenzyme Q6, zizyphine A, and pentadecanal, which might be produced by the microbiota and further affect host metabolism. In conclusion, dietary XOS improved the inflammatory status, gut barrier, and microbiota communities, which might be used as a potential feed additive to prevent gut dysfunction caused by weaning in the pig industry.

Magnolol and Honokiol Attenuate Apoptosis of Enterotoxigenic Escherichia Coli-Induced Intestinal Epithelium by Maintaining Secretion and Absorption Homeostasis and Protecting Mucosal Integrity.

BACKGROUND The cortex of Magnolia officinalis has long been used as an element of traditional Chinese medicine for the treatment of anxiety, chronic bronchitis, and gastrointestinal dysfunction. This study aimed to elucidate the underlying mechanism of its functional ingredients (magnolol and honokiol) in modifying the secretion and absorption homeostasis and protecting mucosal integrity in an Enterotoxigenic Escherichia coli (ETEC)-induced diarrhea mouse model. MATERIAL AND METHODS This study established a diarrhea mouse model infected by ETEC at a dosage of 0.02 ml/g live body weight (BW) in vivo. Magnolol or honokiol was followed by an intraperitoneal administration at dosages of 100, 300, and 500 mg/kg BW according to a 3×3 factorial arrangement. The useful biomarkers for evaluating the integrity of intestinal tract and histologic injury were analyzed and morphological development (including villus height, crypt depth, and ratio of villus height to crypt depth) and the expressions of inflammatory cytokines were determined by real-time PCR. RESULTS The results showed that magnolol and honokiol (500 mg/kg BW) reduced the concentrations of NO, DAO, and DLA, and iNOS activity, and the mRNA expressions of the interferon gamma (IFN-γ) and interleukin 10 (IL-10), and inhibited intestinal epithelial cell apoptosis. Magnolol and honokiol (300 mg/kg BW) elongated the villus height and crypt depth and decreased the number of goblet cells and the ratio of villus height to crypt depth. CONCLUSIONS The current results indicate that magnolol and honokiol enhance the intestinal anti-inflammatory capacities, elongate the villus height and crypt depth, and reduce goblet cell numbers to inhibit the intestinal epithelium apoptosis and effectively protect the intestinal mucosa. These results show that magnolol and honokiol protect the intestinal mucosal integrity and regulate gastrointestinal dysfunction.

Molecular hydrogen generated by elemental magnesium supplementation alters rumen fermentation and microbiota in goats.

We tested the hypotheses that supplementation of a diet with elemental Mg increases ruminal dissolved H2 (dH2) in rumen fluid, which in turn alters rumen fermentation and microbial community in goats. In a randomised block design, twenty growing goats were allocated to two treatments fed the same basal diet with 1·45 % Mg(OH)2 or 0·6 % elemental Mg. After 28 d of adaptation, we collected total faeces to measure total tract digestibility, rumen contents to analyse fermentation end products and microbial groups, and measured methane (CH4) emission using respiration chambers. Ruminal Mg2+ concentration was similar in both treatments. Elemental Mg supplementation increased dH2 at 2·5 h post morning feeding (+180 %, P<0·001). Elemental Mg supplementation decreased total volatile fatty acid concentration (-8·6 %, P<0·001), the acetate:propionate ratio (-11·8 %, P<0·03) and fungal copy numbers (-63·6 %, P=0·006), and increased propionate molar percentage (+11·6 %, P<0·001), methanogen copy numbers (+47·9 %, P<0·001), dissolved CH4 (+35·6 %, P<0·001) and CH4 emissions (+11·7 %, P=0·03), compared with Mg(OH)2 supplementation. The bacterial community composition in both treatments was overall similar. Ruminal dH2 was negatively correlated with acetate molar percentage and fungal copy numbers (P<0·05), and positively correlated with propionate molar percentage and methanogen copy numbers (P<0·05). In summary, elemental Mg supplementation increased ruminal dH2 concentration, which inhibited rumen fermentation, enhanced methanogenesis and seemed to shift fermentation pathways from acetate to propionate, and altered microbiota by decreasing fungi and increasing methanogens.

Effects of dietary supplementation of Acanthopanax senticosus on gastrointestinal tract development in calves.

Twenty-four newborn Holstein dairy male calves (with initial body weight of 38 ± 3.0 kg) were used in a randomized block design experiment to determine effects of dietary supplementation of Acanthopanax senticosus (AS) on gastrointestinal tract development. Calves were fed milk (10%/body weight) three times at 06.00, 12.00 and 18.00 hours daily with one to four treatments during the experimental periods (4 to 28 days): no supplementation of AS (control group, CG); 1.0 g/L•time of micro-powder AS (MP); 1.0 g/L•time of superfine powder AS (SP); or 1.0 g/L•time of coarse powder AS (CP). On days 7, 14, 21 and 28, 20 mL blood samples were collected at 06.00 hours before the morning feeding. At the end of the trial (28 days), all calves were euthanized, and tissue samples were taken and placed in 4% buffered formaldehyde for analyses. In the rumen of MP treatment, compared with the CG treatment, wall thickness and papillae diameter was both significantly lower (P<0.05), while crypt depth was significantly greater (P<0.05). In the duodenum, villi diameter of AS supplemented treatments was significantly lower than that of CG treatment (P<0.05). Results indicate that calves during sucking period supplemented with AS as MP style could promote gastrointestinal development.

Influence of Oleic Acid on Rumen Fermentation and Fatty Acid Formation In Vitro.

A series of batch cultures were conducted to investigate the effects of oleic acid (OA) on in vitro ruminal dry matter degradability (IVDMD), gas production, methane (CH4) and hydrogen (H2) production, and proportion of fatty acids. Rumen fluid was collected from fistulated goats, diluted with incubation buffer, and then incubated with 500 mg Leymus chinensis meal supplemented with different amounts of OA (0, 20, 40, and 60 mg for the CON, OA20, OA40 and OA60 groups, respectively). Incubation was carried out anaerobically at 39°C for 48 h, and the samples were taken at 12, 24 and 48 h and subjected to laboratory analysis. Supplementation of OA decreased IVDMD, the cumulative gas production, theoretical maximum of gas production and CH4 production, but increased H2 production. However, no effect was observed on any parameters of rumen fermentation (pH, ammonia, production of acetate, propionate and butyrate and total volatile fatty acid production). The concentrations of some beneficial fatty acids, such as cis monounsaturated fatty acids and conjugated linoleic acid (CLA) were higher (P < 0.05) from OA groups than those from the control group at 12 h incubation. In summary, these results suggest that the OA supplementation in diet can reduce methane production and increase the amount of some beneficial fatty acids in vitro.

Effects of dietary addition of cellulase and a Saccharomyces cerevisiae fermentation product on nutrient digestibility, rumen fermentation and enteric methane emissions in growing goats.

This study was designed to assess the effectiveness of dietary cellulase (243 U/g, derived from Neocallimastix patriciarum) and a Saccharomyces cerevisiae fermentation product (yeast product) on ruminal fermentation characteristics, enteric methane (CH4) emissions and methanogenic community in growing goats. The experiment was conducted in a 5 × 5 Latin square design using five Xiangdong black wether goats. The treatments included a Control and two levels of cellulase (0.8 g and 1.6 g/kg dry matter intake (DMI), i.e. 194 U/kg and 389 U/kg DMI, respectively) crossed over with two levels (6 g or 12 g/kg DMI) of the yeast product. There were no significant differences regarding feed intake, apparent digestibility of organic matter, neutral detergent fibre and acid detergent fibre among all the treatments. In comparison with the Control, the ruminal ammonia N concentration was decreased (p = 0.001) by cellulase and yeast product addition. The activities of carboxymethylcellulase and xylanase were decreased after cellulase addition. Moreover, dietary cellulase and yeast product addition led to a significant reduction (p < 0.05) of enteric CH4 emissions although the diversity and copy numbers of methanogens among treatments were not dissimilar. The present results indicate that the combination of cellulase and yeast fermentation product can reduce the production of CH4 energy and mitigate the enteric CH4 emissions to a certain degree.

Alteration of antioxidant enzymes and associated genes induced by grape seed extracts in the primary muscle cells of goats in vitro.

This study was conducted to investigate how the activity and expression of certain paramount antioxidant enzymes respond to grape seed extract (GSE) addition in primary muscle cells of goats. Gluteal primary muscle cells (PMCs) isolated from a 3-week old goat were cultivated as an unstressed cell model, or they were exposed to 100 µM H2O2 to establish a H2O2-stimulated cell model. The activities of catalase (CAT), superoxide dismutases (SOD) and glutathione peroxidases (GPx) in combination with other relevant antioxidant indexes [i.e., reduced glutathione (GSH) and total antioxidant capacity (TAOC)] in response to GSE addition were tested in the unstressed and H2O2-stimulated cell models, and the relative mRNA levels of the CAT, GuZu-SOD, and GPx-1 genes were measured by qPCR. In unstressed PMCs, GSE addition at the dose of 10 µg/ml strikingly attenuated the expression levels of CAT and CuZn-SOD as well as the corresponding enzyme activities. By contrast, in cells pretreated with 100 µM H2O2, the expression and activity levels of these two antioxidant enzymes were enhanced by GSE addition at 10 µg/ml. GSE addition promoted GPx activity in both unstressed and stressed PMCs, while the expression of the GPx 1 gene displayed partial divergence with GPx activity, which was mitigated by GSE addition at 10 µg/ml in unstressed PMCs. GSH remained comparatively stable except for GSE addition to H2O2-stimulated PMCs at 60 µg/ml, in which a dramatic depletion of GSH occurred. Moreover, GSE addition enhanced TAOC in unstressed (but not H2O2-stimulated) PMCs. GSE addition exerted a bidirectional modulating effect on the mRNA levels and activities of CAT and SOD in unstressed and stressed PMCs at a moderate dose, and it only exhibited a unidirectional effect on the promotion of GPx activity, reflecting its potential to improve antioxidant protection in ruminants.

Effect of tea catechins on regulation of antioxidant enzyme expression in H2O2-induced skeletal muscle cells of goat in vitro.

Skeletal muscle cells (SMCs) of goats were stress induced with 1 mM H(2)O(2) in the absence or presence of 0.5, 5, and 50 µg/mL tea catechins (TCs) incubation. Cells were harvested at 48 h postincubation with TCs to investigate the effects of TCs on cell proliferation, cell membrane integrity, antioxidant enzyme activities, and antioxidant enzyme genes and protein expression levels. Results showed that H(2)O(2) induction inhibited cell proliferation with or without TC incubation; moreover, the inhibition effect was enhanced in the presence of TCs (P < 0.001). H(2)O(2)-induced stress increased the lactate dehydrogenase (LDH) activity in the absence or presence of TC incubation, but concentrations of TCs, less than 5 µg/mL, showed protective functions against LDH leakage than in other H(2)O(2)-induced treatments. The catalase (CAT) activity increased when SMCs were stress induced with H(2)O(2) in the absence or presence of TC incubation (P < 0.001). H(2)O(2)-induced stress decreased CuZn superoxide dismutase (CuZn-SOD) and glutathione peroxidase (GPx) activities, whereas this effect was prevented by incubation with TCs in a concentration-dependent manner. H(2)O(2)-induced stress with or without TC incubation had significant effects on mRNA and protein expression levels of CAT, CuZn-SOD, and GPx (P < 0.001). CAT and CuZn-SOD mRNA expression levels were increased by different concentrations of TC incubation, and this tendency was basically consistent with corresponding protein expression levels. The GPx mRNA expression level increased with a low concentration of TCs but decreased with concentrations greater than 5 µg/mL of TCs, whereas GPx protein expression in all TC-incubated groups was lower than in the control treatment. The current findings imply that TCs had an inhibitory effect on cell proliferation and enhanced damage to the cell membrane integrity, but TCs affected antioxidant status in SMCs by modulating antioxidant enzyme activities at mRNA and protein expression levels.

Effects of alkyl polyglycoside, a nonionic surfactant, and forage-to-concentrate ratio on rumen fermentation, amino acid composition of rumen content, bacteria and plasma in goats.

In the present study, the effects of different forage-to-concentrate ratios (F:C) and an alkyl polyglycoside (APG) supplementation on parameters of rumen and blood metabolism were investigated in goats. A 2 x 2 factorial experiment was arranged within a 4 x 4 Latin square design (four 22-day periods), using four wether goats equipped with permanent ruminal cannulas. The experimental diets included two F:C levels (40:60 vs. 60:40), and two APG supplementation levels (None or 13 ml APG daily per animal). Rumen contents and blood samples were collected at the end of each period. Dietary F:C alteration affected plasma urea and influenced the proportions of leucine, histidine, arginine, glycine, proline, alanine, valine, phenylalanine, cysteine and tyrosine in rumen content, and the proportions of methionine, threonine and proline in solid-associated bacteria (SAB) significantly. Dietary APG decreased the proportions of valine and phenylalanine in rumen content, and the histidine content of liquid-associated bacteria. The interaction between dietary F:C and APG was significant for the proportions of glycine and alanine in rumen content, and the proportions of lysine and threonine in SAB. The proportion of lysine was greater, but the proportion of threonine was less in SAB for goats fed high F:C diet without APG supplementation. The proportions of plasma free amino acids and glucose concentration were not affected by experimental treatments. These results indicated that dietary APG addition affected the amino acid composition of the rumen content and ruminal bacteria, but this depended on the dietary F:C ratio. It is necessary to validate the effectiveness of dietary APG supplementation in further studies with more animals.