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1.
This experiment was conducted to investigate the effects of dietary sodium acetate on lactation performance and rumen microbiota of dairy goats. Fifteen healthy Xinong Saanen dairy goat ewes with similar body weight of (53.54±3.07) kg, the same parity (2 parities) and in mid-lactation [(60±5) d] were randomly divided into 3 groups with 5 replicates in each group. Dairy goats in the control group were fed a basal diet, and those in the experimental groups were fed the basal diet supplemented with 30 (experimental group I) and 60 g/ (d.head) (experimental group II) sodium acetate, respectively. The pre-trial period lasted for 7 days and the experimental period lasted for 21 days. The milk yield of dairy goats was recorded during the experiment. At the end of the experiment, milk samples were collected to analyze the changes in milk composition, and rumen contents of dairy goats were collected from two groups (control group and experimental group II) with significant differences in milk fat percentage. Gas chromatography and 16S rDNA sequencing technology were used to analyze the rumen fermentation parameters and rumen microbial composition and structure of dairy goats. The results showed as follows: 1) compared with the control group, dietary sodium acetate extremely significantly increased the daily milk yield of dairy goats (P<0.01), and the daily milk yield in experimental groups I and II was increased by 0.29 and 0.22 kg, respectively (P<0.01); in experimental group II, the milk fat percentage was significantly increased by 1.30 percentage points (P<0.01), and the non-fat solid content in milk was increased by 3.10% (P>0.05). 2) Compared with the control group, the rumen butyric acid content of dairy goats in experimental group II was significantly decreased (P<0.01), and there was no significant difference in rumen pH, the other volatile fatty acid content and acetic acid to propionic acid ratio (P>0.05). 3) Compared with the control group, the Sobs index, Chao1 index and Ace index of rumen microbiota in experimental group II were significantly increased (P<0.05); the results of similarity analysis (ANOSIM) also showed that there were significant differences in the structure of rumen microbiota between the two groups (P<0.05). 16S rDNA sequencing results showed that at the phylum level, Bacteroidetes and Firmicutes were the dominant phyla in the rumen of the two groups of dairy goats; at the genus level, Prevotella_1 was the dominant genus in the rumen. Compared with the control group, the relative abundances of Ruminococcus_1, Ruminococcaceae_UCG-005, Prevotellaceae_UCG-004 and Lachnoclostridium_12 in rumen of dairy goats in experimental group II were significantly increased (P<0.05), while the relative abundances of Succiniclasticum and Methanobrevibacter in rumen was significantly decreased (P<0.05). 4) The results of correlation analysis showed that rumen microbiota was correlated with daily milk yield, milk fat percentage, milk protein percentage and non-fat solid content of dairy goats. In conclusion, dietary 60 g/ (d.head) sodium acetate can significantly increase the daily milk yield and milk fat percentage, significantly reduce rumen butyrate content, and improve the lactation performance of dairy goats by improving rumen microbial composition and structure. © 2023 Authors. All rights reserved.  相似文献   

2.
The aim of this experiment was to investigate the changes of rumen microbiota density and physicochemical properties at different pH. Five Holstein cows in dry milk period were selected as rumen fluid donors. Using in vitro method, five treatments were set according to the criteria of rumen acidosis, and the pH of culture medium was 6.5, 5.8, 5.5, 5.2 and 5.0, respectively, with five replicates in each treatment. After three hours of incubation, the changes of rumen microbiota density and physicochemical properties were measured. The results showed as follows: 1) with the decrease of pH, the rumen microbiota density showed a fluctuation change of first decreasing, then increasing and then decreasing, and the microbiota density in pH 5.8 treatment was significantly lower than that in pH 6.5 treatment (P<0.05). When pH was 5.2, the rumen microbiota density was the highest, which was significantly higher than that in the other treatments (P<0.05). 2) With the decrease of pH, the intracellular H+-ATPase activity in rumen microbiota was firstly increased and then decreased, but there was no significant difference among all treatments (P>0.05). 3) The intracellular ATP content in rumen microbiota was not significantly affected by different pH treatments (P>0.05). 4) With the decrease of pH, the intracellular protein content in rumen microbiota was gradually increased (P<0.05). 5) With the decrease of pH, the intracellular pH (pHi) and cellular transmembrane pH difference (ΔpH) in rumen microbiota were firstly increased and then decreased, and the pHi and ΔpH in pH 5.5 and 5.2 treatments were significantly higher than those in the other three treatments (P<0.05). 6) With the decrease of pH, the cell membrane permeability of rumen microbiota was gradually increased, except for pH 5.8 treatment, the other treatments were significantly higher than pH 6.5 treatment (P<0.05). In conclusion, the rumen microbiota can increase the intracellular H+-ATPase activity and protein content, consume ATP, and change pHi and ΔpH in response to external pH decline. When pH decreases to 5.5, the membrane permeability and pHi of rumen microbiota increase significantly, indicating that they are running to be subjected to more serious acid stress. The density of rumen microbiota fluctuates with the decrease of pH, and when pH decreases to 5.2, the density of rumen microbiota is the highest. © 2023 Authors. All rights reserved.  相似文献   

3.
This experiment was conducted to study the effects of Bacillus amylolyticus on rumen dry matter digestibility, fermentation parameters and metabolites of dairy cows. Experiment 1: six dairy cows with permanent fistula and had the similar parity (2 to 3 fetuses), body weight [(662 ±57) kg], lactation days [(160 ± 22) d] and milk yield [(36.1 ±3.8) kg / d], were randomly divided into 3 groups with 2 cows per group. Using 3 ×3 Latin square design, each group was extra fed 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, the trial period was 3 periods, 13 days for each period, including 10 days for the pre-trial period and 3 days for the trial period. At the beginning of the trial period, the rumen dry matter digestibility of cows was measured by nylon bag method. Experiment 2: thirty dairy cows with similar parity [(2.5 ±0.3) fetuses], initial body weight [(559.2 ± 7. 4) kg], milk yield [(35. 2 ± 1. 5) kg / d] and lactation days [(99 ± 22) d] were randomly divided into three groups with 10 cows in each group. Cows in the 3 groups were extra fed with 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, respectively. The pre-trial period was 10 days and the trial period was 42 days. The rumen fluid was collected on the last day of the trial period, and the rumen fermentation parameters and metabolites were determined. The results showed as follows: compared with the control group, 1) supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 12, 24, 36, 48 and 72 h (P <0.05), supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 36 and 48 h (P <0.05); 2) supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid, butyric acid, isovaleric acid, valeric acid, total volatile fatty acid and microbial protein in the rumen of dairy cows (P < 0. 05), supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid and isovaleric acid in the rumen of dairy cows and significantly reduce the rumen acetic acid / propionic acid (P < 0. 05), supplementary feeding of 5 ×109 and 5 ×1010 Bacillus amylolyticus had no effects on rumen pH and ammonia nitrogen content (P >0.05); 3) eleven metabolic pathways related to differential metabolites were detected, and ascorbic acid and alginate metabolism were significantly enriched (P < 0. 05) . In conclusion, Bacillus amylolyticus can increase the rumen dry matter digestibility, and improve the rumen fermentation function of dairy cows by affecting the content of rumen metabolites. By comprehensive analysis, supplementary feeding of 5 × 109 CFU / d Bacillus amylolyticus can achieve better effect. © 2023 Authors. All rights reserved.  相似文献   

4.
The purpose of this study was to investigate the effects of compound bacteria preparation (including homogeneous Lactobacillus/heterogeneous Lactobacillus, Bacillus subtilis and Aspergillus niger as well as their compatibility) on nutrient composition, fermentation quality and rumen fermentation characteristics of Phragmites australis silage. Taking growing Phragmites australis from Dongting lake as silage material, five groups were set up, which were blank group (CK group), lactic acid bacteria group (LA group, supplemented with Lactobacillus plantarum, Pediococcus pentosaceus and Lactobacillus buchneri), lactic acid bacteria+Bacillus subtilis group (LA+BS group), lactic acid bacteria+Aspergillus niger group (LA+AN group) and lactic acid bacteria+Bacillus subtilis+Aspergillus niger group (LA+BS+AN group), and each group had 3 replicates. The supplemental level of lactic acid bacteria was 1.5×108 CFU/kg silage raw materials, and the supplemental levels of Aspergillus niger and Bacillus subtilis were 1.0×108 CFU/kg silage raw materials (all were based on fresh weight of silage raw materials). After 60 days of silage, the nutrient composition and fermentation quality of Phragmites australis silage were determined, and the rumen fermentation characteristics were evaluated by in vitro fermentation and in vivo degradation. The results showed as follows: 1) the contents of dry matter and ash in LA, LA+BS and LA+AN groups were significantly lower than those in CK group (P<0.05), and the crude protein content in LA+BS, LA+AN and LA+BS+AN groups was significantly higher than that in CK and LA groups (P<0.05). 2) The silage sensory evaluation scores of all groups were 60 to 70 points, and the ratings were good. The comprehensive scores of fermentation quality in LA+BS and LA+AN groups were higher, among which, the ammonia nitrogen to total nitrogen ratio, acetic acid content and acetic acid to total acid ratio in LA+AN group were significantly decreased compared with CK group (P<0.05), while the lactic acid content and lactic acid to total acid ratio were significantly increased compared with CK group (P<0.05). 3) The dry matter disappearance rate and total gas production of in vitro fermentation in LA+AN group were significantly higher than those in the other groups (P<0.05), and in vitro fermentation parameters such as volatile fatty acid contents in fermentation liquid were improved. 4) The rumen fermentation dry matter degradation rate in LA+AN and LA+BS+AN groups at 8, 24 and 48 h was significantly higher than that in the other three groups (P<0.05). In conclusion, the combined application of lactic acid bacteria and Aspergillus niger with supplemental levels in this experiment has the best effect on the quality of Phragmites australis silage and rumen fermentation characteristics. © The Author(s) 2023.  相似文献   

5.
Background:Endolysins,the bacteriophage-originated peptidoglycan hydrolases,are a promising replacement for antibiotics due to immediate lytic activity and no antibiotic resistance.The objectives of this study were to investigate the lytic activity of endolysin LyJH307 against S.bovis and to explore changes in rumen fermentation and microbiota in an in vitro system.Two treatments were used:1)control,corn grain without LyJH307;and 2)LyJH307,corn grain with LyJH307(4 U/mL).An in vitro fermentation experiment was performed using mixture of rumen fluid collected from two cannulated Holstein steers(450±30 kg)and artificial saliva buffer mixed as 1:3 ratio for 12 h incubation time.In vitro dry matter digestibility,pH,volatile fatty acids,and lactate concentration were estimated at 12 h,and the gas production was measured at 6,9,and 12 h.The rumen bacterial community was analyzed using 16S rRNA amplicon sequencing.Results:LyJH307 supplementation at 6 h incubation markedly decreased the absolute abundance of S.bovis(approximately 70% compared to control,P=0.0289)and increased ruminal pH(P=0.0335)at the 12 h incubation.The acetate proportion(P=0.0362)was significantly increased after LyJH307 addition,whereas propionate(P=0.0379)was decreased.LyJH307 supplementation increased D-lactate(P=0.0340)without any change in L-lactate concentration(P>0.10).There were no significant differences in Shannon’s index,Simpson’s index,Chao1 estimates,and evenness(P>0.10).Based on Bray-Curtis dissimilarity matrices,the LyJH307 affected the overall shift in microbiota(P=0.097).LyJH307 supplementation induced an increase of 11 genera containing Lachnoclostridium,WCHB1-41,unclassified genus Selenomonadaceae,Paraprevotella,vadinBE97,Ruminococcus gauvreauii group,Lactobacillus,Anaerorhabdus furcosa group,Victivallaceae,Desulfuromonadaceae,and Sediminispirochaeta.The predicted functional features represented by the Kyoto Encyclopedia of Genes and Genomes pathways were changed by LyJH307 toward a decrease of carbohydrate metabolism.Conclusions:LyJH307 caused a reduction of S.bovis and an increase of pH with shifts in minor microbiota and its metabolic pathways related to carbohydrate metabolism.This study provides the first insight into the availability of endolysin as a specific modulator for rumen and shows the possibility of endolysin degradation by rumen microbiota.  相似文献   

6.
Methane from enteric fermentation is the gas with the greatest environmental impact emitted by ruminants.Lovastatin(Lv)addition to feedstocks could be a strategy to mitigate rumen methane emissions via decreasing the population of methanogenic archaea(MA).Thus,this paper provides the first overview of the effects of Lv supplementation,focusing on the inhibition of methane production,rumen microbiota,and ruminal fermentation.Results indicated that Lv treatment had a strong anti-methanogenic effect on pure strains of MA.However,there are uncertainties from in vitro rumen fermentation trials with complex substrates and rumen inoculum.Solid-state fermentation(SSF)has emerged as a cost-effective option to produce Lv.In this way,SSF of agricultural residues as an Lv-carrier supplement in sheep and goats demonstrated a consistent decrease in ruminal methane emissions.The experimental evidence for in vitro conditions showed that Lv did not affect the volatile fatty acids(VFA).However,in vivo experiments demonstrated that the production of VFA was decreased.Lv did not negatively affect the digestibility of dry matter during in vitro and in vivo methods,and there is even evidence that it can induce an increase in digestibility.Regarding the rumen microbiota,populations of MA were reduced,and no differences were detected in alpha and beta diversity associated with Lv treatment.However,some changes in the relative abundance of the microbiota were induced.Further studies are recommended on:(i)Lv biodegradation products and stability,as well as its adsorption onto the solid matter in the rumen,to gain more insight on the“available”or effective Lv concentration;and(ii)to determine whether the effect of Lv on ruminal fermentation also depends on the feed composition and different ruminants.  相似文献   

7.
Background: Rumen microbiome has a great influence on ruminant health and productivity. Different plant extracts have been tested for their ability to modulate the rumen microbiome to improve feed digestion and fermentation. Among the evaluated plant extracts, essential oils, tannins, and saponins appeared to have positive effects on rumen protein metabolism, volatile fatty acids production, and methane and ammonia production.Methods: The objective of this study was to evaluate the effect of rosemary(Rosmarinus officinalis L.) leaves and essential oils on rumen microbial populations. Four ruminally cannulated sheep were used in a 4×4 Latin square design fed(21 d/period): 1) a control diet composed of alfalfa hay and concentrate pellet(CTR), 2) CTR supplemented with 7 g/d/sheep of rosemary essential oil adsorbed on an inert support(EO), 3) CTR with 10 g/d/sheep of dried and ground rosemary leaves(RL), and 4) CTR with 10 g/d of dried and ground rosemary leaves pelleted into concentrate(RL pellet). Abundance of total bacteria, archaea, protozoa, and some select bacterial species or groups was quantified using q PCR, while the community of bacteria and archaea was profiled using denaturing gradient gel electrophoresis.Results: No difference in abundance was noted for total bacteria, protozoa, or Ruminococcus flavefaciens between the control and the treatments, but the rosemary leaves, either in loose form or in pellet, decreased the abundance of archaea and the genus Prevotella(P 0.001). The rosemary leaves in loose form also decreased(P 0.001) the abundance of Ruminococcus albus and Clostridium aminophilum, while the EO increased(P 0.001) the abundance of Fibrobacter succinogenes. The community of bacteria and archaea was not affected by any of the supplements.Conclusions: Being able to affect the abundance of several groups of rumen microbes that are known to be involved in degradation of protein and fiber and production of methane and ammonia, rosemary leaves may be used to modulate rumen microbiome and its function.  相似文献   

8.
Background：Methane（CH_4） emissions in cattle are an undesirable end product of rumen methanogenic fermentative activity as they are associated not only with negative environmental impacts but also with reduced host feed efficiency.The aim of this study was to quantify total and specific rumen microbial methanogenic populations in beef cattle divergently selected for residual feed intake（RFI） while offered（i） a low energy high forage（HF） diet followed by（ii） a high energy low forage（LF） diet.Ruminal fluid was collected from 14 high（H）and 14 low（L） RFI animals across both dietary periods.Quantitative real time PCR（qRT-PCR） analysis was conducted to quantify the abundance of total and specific rumen methanogenic microbes.Spearman correlation analysis was used to investigate the association between the relative abundance of methanogens and animal performance,rumen fermentation variables and diet digestibility.Results：Abundance of methanogens,did not differ between RFI phenotypes.However,relative abundance of total and specific methanogen species was affected（P〈 0.05） by diet type,with greater abundance observed while animals were offered the LF compared to the HF diet.Conclusions：These findings suggest that differences in abundance of specific rumen methanogen species may not contribute to variation in CH_4 emissions between efficient and inefficient animals,however dietary manipulation can influence the abundance of total and specific methanogen species.  相似文献   

9.
Background: In ruminants, dietary C18:3 n-3 can be lost through biohydrogenation in the rumen; and C18:3 n-3 that by-passes the rumen still can be lost through oxidation in muscle, theoretically reducing the deposition of C18:3 n-3,the substrate for synthesis of poly-unsaturated fatty acids(n-3 LCPUFA) in muscle. In vitro studies have shown that rumen hydrogenation of C18:3 n-3 is reduced by supplementation with palm oil(rich in cis-9 C18:1). In addition, in hepatocytes, studies with neonatal rats have shown that cis-9 C18:1 inhibits the oxidation of C18:3 n-3. It therefore seems likely that palm oil could reduce both rumen biohydrogenation of C18:3 n-3 and muscle oxidation of C18:3 n-3. The present experiment tested whether the addition of palm oil to a linseed oil supplement for goat kids would prevent the losses of C18:3 n-3 and thus improve the FA composition in two muscles, Longissimus dorsi and Biceps femoris. To investigate the processes involved, we studied the rumen bacterial communities and measured the mRNA expression of genes related to lipid metabolism in Longissimus dorsi. Sixty 4-month-old castrated male Albas white cashmere kids were randomly allocated among three dietary treatments. All three diets contained the same ingredients in the same proportions, but differed in their fat additives: palm oil(PMO), linseed oil(LSO) or mixed oil(MIX; 2 parts linseed oil plus 1 part palm oil on a weight basis).Results: Compared with the LSO diet, the MIX diet decreased the relative abuandance of Pseudobutyrivibrio, a bacterial species that is positively related to the proportional loss rate of dietary C18:3 n-3 and that has been reported to generate the ATP required for biohydrogenation(reflecting a decrease in the abundance of rumen bacteria that hydrogenate C18:3 n-3 in MIX kids). In muscle, the MIX diet increased concentrations of C18:3 n-3, C20:5 n-3, C22:6 n-3,and n-3 LCPUFA, and thus decreased the n-6/n-3 ratio; decreased the mRNA expression of CPT1β(a gene associated with fatty acid oxidation) and increased the mRNA expression of FADS1 and FADS2(genes associated with n-3 LCPUFA synthesis), compared with the LSO diet. Interestingly, compared to Longissimus dorsi, Biceps femoris had greater concentrations of PUFA, greater ratios of unsaturated fatty acids/saturated fatty acids(U/S), and poly-unsaturated fatty acids/saturated fatty acids(P/S), but a lesser concentration of saturated fatty acids(SFA).Conclusions: In cashmere goat kids, a combination of linseed and palm oils in the diet increases the muscle concentration of n-3 LCPUFA, apparently by decreasing the relative abundance of rumen bacteria that are positively related to the proportional loss rate of dietary C18:3 n-3, by inhibiting m RNA expression of genes related to C18:3 n-3 oxidation in muscle, and by up-regulating m RNA expression of genes related to n-3 LCPUFA synthesis in muscle,especially in Longissimus dorsi.  相似文献   

10.
Background: The interaction of the gut microbiota with key metabolic and physiological processes may be associated with poor growth outcomes in animals born with intrauterine growth restriction(IUGR).Results: Growth performance, plasma hormone concentrations, and intestinal microbiota composition were analyzed in IUGR pigs and in normal birth weight(NBW) pigs when the NBW pigs reached 25, 50, and 100 kg of body weight(BW). Compared to NBW pigs, IUGR pigs had lower initial, weaned, and final BW, and lower average daily gain and average daily feed intake in all the considered time points. In the 25 kg BW group, IUGR pigs had higher concentrations of plasma ghrelin and pancreatic polypeptide(PP), but lower insulin concentration than NBW pigs, while the situation was reversed in the 50 kg BW group. As compared to NBW pigs, IUGR pigs had higher microbial alpha diversity in the jejunum and ileum;in the 50 and 100 kg BW groups, IUGR pigs had higher Firmicutes abundance but lower Proteobacteria abundance in the jejunum, and lower Lactobacillus abundance in the jejunum and ileum;in the 25 kg BW group, IUGR pigs showed higher unclassified Ruminococcaceae abundance in the ileum;and in 25 and 50 kg BW groups, IUGR pigs showed lower Ochrobactrum abundance in the jejunum.Spearman's correlation revealed that Lactobacillus was negatively correlated with growth performance, while unclassified Ruminococcaceae was positively correlated. Predictive metagenomic analysis detected significantly different expression of genes in the intestinal microbiota between IUGR and NBW pigs, suggesting different metabolic capabilities between the two groups.Conclusions: Growing-finishing IUGR pigs showed lower growth performance, higher microbial alpha diversity, and differences in plasma hormone concentrations compared to NBW pigs. Alterations in the abundance of Firmicutes,Proteobacteria, Ruminococcaceae, Lactobacillus, and Ochrobactrum in the small intestine may be associated with IUGR, and may therefore serve as a future target for gut microbiota intervention in growing-finishing IUGR pigs.  相似文献   

11.
Background:A run of homozygosity(ROH)is a consecutive tract of homozygous genotypes in an individual that indicates it has inherited the same ancestral haplotype from both parents.Genomic inbreeding can be quantified based on ROH.Genomic regions enriched with ROH may be indicative of selection sweeps and are known as ROH islands.We carried out ROH analyses in five Chinese indigenous sheep breeds;Altay sheep(n=50 individuals),Large-tailed Han sheep(n=50),Hulun Buir sheep(n=150),Short-tailed grassland sheep(n=150),and Tibetan sheep(n=50),using genotypes from an Ovine Infinium HD SNP BeadChip.Results:A total of 18,288 ROH were identified.The average number of ROH per individual across the five sheep breeds ranged from 39(Hulun Buir sheep)to 78(Large-tailed Han sheep)and the average length of ROH ranged from 0.929 Mb(Hulun Buir sheep)to 2.544 Mb(Large-tailed Han sheep).The effective population size(Ne)of Altay sheep,Large-tailed Han sheep,Hulun Buir sheep,Short-tailed grassland sheep and Tibetan sheep were estimated to be 81,78,253,238 and 70 five generations ago.The highest ROH-based inbreeding estimate(FROH)was 0.0808 in Large-tailed Han sheep,whereas the lowest FROHwas 0.0148 in Hulun Buir sheep.Furthermore,the highest proportion of long ROH fragments(>5 Mb)was observed in the Large-tailed Han sheep breed which indicated recent inbreeding.In total,49 ROH islands(the top 0.1% of the SNPs most commonly observed in ROH)were identified in the five sheep breeds.Three ROH islands were common to all the five sheep breeds,and were located on OAR2:12.2-12.3 Mb,OAR12:78.4-79.1 Mb and OAR13:53.0-53.6 Mb.Three breed-specific ROH islands were observed in Altay sheep(OAR15:3.4-3.8 Mb),Large-tailed Han sheep(ORA17:53.5-53.8 Mb)and Tibetan sheep(ORA5:19.8-20.2 Mb).Collectively,the ROH islands harbored 78 unique genes,including 19 genes that have been documented as having associations with tail types,adaptation,growth,body size,reproduction or immune response.Conclusion:Different ROH patterns were observed in five Chinese indigenous sheep breeds,which reflected their different population histories.Large-tailed Han sheep had the highest genomic inbreeding coefficients and the highest proportion of long ROH fragments indicating recent inbreeding.Candidate genes in ROH islands could be used to illustrate the genetic characteristics of these five sheep breeds.Our findings contribute to the understanding of genetic diversity and population demography,and help design and implement breeding and conservation strategies for Chinese sheep.  相似文献   

12.
Background: Extensive degradation of amino acids in the rumen via microbial deamination decreases the postruminal availability of dietary indispensable amino acids. Together with the normal decrease in voluntary dry matter intake(DMI) around parturition in dairy cows, microbial metabolism contributes to a markedly negative balance of indispensable amino acids, including methionine which may be the first-limiting for milk production. The main objective of the current study was to profile changes in major bacterial species with key functions in cel ulose and hemicel ulose digestion, xylan breakdown, proteolytic action, propionic acid production, lactate utilization and ruminal biohydrogenation in cows supplemented with rumen-protected Methionine(SM; Smartamine M, Adisseo NA, Alpharetta,GA, USA) from-23 through 30 d relative to parturition. Because ~90% of the methionine in SM bypasses the rumen,~10% of the methionine is released into the rumen and can be utilized by microbes.Results: As expected, there was an increase in overall DMI after parturition(Day, P 0.05) during which cows consumed on average 19.6 kg/d versus 13.9 kg/d in the prepartum period. The postpartum diet contained greater concentrations of lipid and highly-fermentable carbohydrate from corn grain, which likely explains the increases in the relative abundance of Anaerovibrio lipolytica, Megasphaera elsdenii, Prevotella bryantii, Selenomonas ruminantium,Streptococcus bovis, and Succinimonas amylolytica. Despite similar DMI prepartum, cows fed SM had greater(Treatment × Day, P 0.05) abundance prepartum of Fibrobacter succinogenes, Succinimonas amylolytica, and Succinivibrio dextrinosolvens. However, the greater DMI in cows fed SM after parturition(19.6 kg/d versus 13.9 kg/d) was associated with lower abundance of Fibrobacter succinogenes(2.13 × 10-3 versus 2.25 × 10-4) and Selenomonas ruminantium(2.98 × 10-1 versus 4.10 × 10-1). A lower abundance(Day, P 0.05) was detected on d 20 compared with d-10 for Fibrobacter succinogenes and Succinivibrio dextrinosolvens. The relative abundance of Butyrivibrio proteoclasticus and Eubacterium ruminantium was stable across treatment and time.(Continued from previous page)Conclusions: In diets with proper balance of rumen-degradable protein and fermentable carbohydrate, the smal fraction of Methionine released from the rumen-protected supplement did not seem to compromise growth of major bacterial species in the rumen. In fact, it had a positive effect on 3 major species prepartum when DMI was similar between groups. Because the actual requirements of Methionine(and Lysine, for example) by the cow during the transition period are unknown, it appears warranted to study the rumen microbiome as it relates to supply of rumen-protected amino acids.  相似文献   

13.
The aim of this experiment was to investigate the effects of compound preparation of Chinese herbal extract on performance, immune and antioxidant function and ruminal bacterial flora of cows with high somatic cell count (SCC) in milk. Ten transitional Holstein cows with similar body condition, lactation period, milk yield and milk SCC higher than 500 000 cells / mL were selected and divided into control group [milk SCC = (97.48±23.75) ten thousand cells / mL] and experimental group [milk SCC = (98. 78 ± 29. 92) ten thousand cells / mL] based on the principle of similar milk SCC, each group contained 5 cows, and cows in 2 groups were not treated with medication. The control group was fed a total mixed ration (TMR), and the experimental was fed the TMR+54 g / (d.head) compound preparation of Chinese herbal extract. The experiment lasted for 35 days. The results showed as follows: 1) compared with the control group, the addition of compound preparation of Chinese herbal extract in the diet significantly decreased the SCC in milk at days 14 and 28 of cows with high SCC in milk (P<0.05), but had no significant effects on milk yield, milk composition and nutrient apparent digestibility (P>0.05) . 2) Compared with the control group, the addition of compound preparation of Chinese herbal extract in the diet significantly increased the contents of immunoglobulin A (IgA), immunoglobulin M (IgM) and interferon-γ (IFN-γ) in serum of cows with high SCC in milk (P<0.05), and significantly decreased the serum tumor necrosis factor-α (TNF-α) content (P<0.05) . 3) Compared with the control group, the addition of compound preparation of Chinese herbal extract in the diet significantly decreased the proportions of Actinobacteria, Succinivibrionaceae_UCG-001 and Ruminococcus_gauvreauii_group in rumen of cows with high SCC in milk (P < 0. 05), and significantly increased the rumen Prevotellaceae_UCG-001 proportion (P<0.05) . It is concluded that the addition of compound preparation of Chinese herbal extract in the diet can reduce the SCC in milk, increase the immune function, and improve the rumen bacterial flora composition of cows with high SCC in milk. © 2023 Authors. All rights reserved.  相似文献   

14.
Methane emissions from ruminant livestock contribute significantly to the large environmental footprint of agriculture.The rumen is the principal source of methane, and certain features of the microbiome are associated with low/high methane phenotypes. Despite their primary role in methanogenesis, the abundance of archaea has only a weak correlation with methane emissions from individual animals. The composition of the archaeal community appears to have a stronger effect, with animals harbouring the Methanobrevibacter gottschalki clade tending to be associated with greater methane emissions. Ciliate protozoa produce abundant H_2, the main substrate for methanogenesis in the rumen,and their removal(defaunation) results in an average 11% lower methane emissions in vivo, but the results are not consistent. Different protozoal genera seem to result in greater methane emissions, though community types(A, AB, B and O) did not differ. Within the bacteria, three different ‘ruminotypes' have been identified, two of which predispose animals to have lower methane emissions. The two low-methane ruminotypes are generally characterized by less abundant H_2-producing bacteria. A lower abundance of Proteobacteria and differences in certain Bacteroidetes and anaerobic fungi seem to be associated with high methane emissions. Rumen anaerobic fungi produce abundant H_2 and formate, and their abundance generally corresponds to the level of methane emissions. Thus, microbiome analysis is consistent with known pathways for H_2 production and methanogenesis, but not yet in a predictive manner. The production and utilisation of formate by the ruminal microbiota is poorly understood and may be a source of variability between animals.  相似文献   

15.
Live yeast（Saccharomyces cerevisiae） constitutes an effective additive for animal production;its probiotic effect may be related to the concentrate-to-forage ratio（CTFR）.The objective of this study was to assess the effects of S.cerevisiae（SC） on fiber degradation and rumen microbial populations in steers fed diets with different levels of dietary concentrate.Ten Simmental × Local crossbred steers（450 ± 50 kg BW） were assigned to a control group or an SC group.Both groups were fed the same basal diet but the SC group received SC supplementation（8 × 10^9 cfu/h/d through the ruminal fistula）following a two-period crossover design.Each period consisted of four phases,each of which lasted 17 d：10 d for dietary adaptation,6 d for degradation study,and 1 d for rumen sample collection.From the 1~（st） to the 4~（th） phase,steers were fed in a stepwise fashion with increasing CTFRs,i.e.,30：70,50：50,70：30,and 90：10.The kinetics of dry matter and fiber degradation of alfalfa pellets were evaluated;the rumen microbial populations were detected using real-time PCR.The results revealed no significant（P〉 0.05） interactions between dietary CTFR and SC for most parameters.Dietary CTFR had a significant effect（P〈 0.01） on degradation characteristics of alfalfa pellets and the copies of rumen microorganism;the increasing concentrate level resulted in linear,quadratic or cubic variation trend for these parameters.SC supplementation significantly（P〈 0.05） affected dry matter（DM） and neutral detergent fiber（NDF）degradation rates（c_（DM）,c_（NDF）） and NDF effective degradability（ED_（NDF））.Compared with the control group,there was an increasing trend of rumen fungi and protozoa in SC group（P 〈 0.1）;copies of total bacteria in SC group were significantly higher（P〈 0.05）.Additionally,percentage of Ruminobacter amylophilus was significantly lower（P〈 0.05）but percentage of Selenomonas ruminantium was significantly higher（P〈 0.05） in t  相似文献   

16.
A single nucleotide polymorphism(SNP)of 805 bp region in the intron 6 of transforming growth factor β1(TGF-β1)gene was identified by polymerase chain reaction-single-strand composition polymorphism(PCR-SSCP)in 196 sheep among Small-tailed Han sheep,Tong sheep,Tan sheep and Oula sheep.Comparative sequence analysis of cloned products revealed an AGAC deletion at 294 bases upstream of exon 7 of the TGF-β1 gene(site 14201 in gi76871756).Statistical results of the genotype and allele frequencies in different breeds showed that genotype AB was dominant in the Small-tailed Han sheep.Genotype BB,however,was in majority in low-fecundity sheep.The results of a Chi-square test indicated that all the populations were in Hardy-Weinberg equilibrium.  相似文献   

17.
The experiment was conducted to study the effects of fermented soybean residues on growth performance, apparent nutrient digestibility, meat quality and blood physiological indexes of Hu sheep, and to investigate the value of fermented soybean residues in the production of meat sheep. In the present study, twenty-one healthy male Hu sheep with similar body weight were selected and randomly allocated into a basal diet （control） group, a soybean residue group （basal diet+20% soybean residue, SR） or a fermented soybean residues group （basal diet+20% fermented soybean residues, FSR）, with 7 animals in each group. The experiment lasted for 49 days, including a 7-day adaptation period. The results were as follows: 1）Compared with the control and SR groups, addition of 20% fermented soybean residues in the diet （FSR） significantly increased the average daily weight gain of Hu sheep （P< 0.05） and significantly reduced the weight gain cost （P<0.05）. 2） The apparent digestibility of dry matter （DM）, crude protein （CP） and neutral detergent fiber （NDF） of Hu sheep in the fermented soybean residues group was significantly higher than that in other groups （P<0.05）. 3） Compared with the SR group, the carcass weight of the FSR group was increased （P<0.05）, while the dressing percentage, meat redness values of the FSR group were greater than those of the other groups （P<0.05）, and the drip loss was lower than other groups （P<0.05）. 4） Compared with the control and SR groups, the serum total protein content of the FSR group was increased （P< 0.05）, and the urea nitrogen content was reduced （P<0.05）. Compared with the SR group, the serum albumin content of the FSR group was increased significantly （P<0.05）. In conclusion, the addition of fermented soybean residues in the diet significantly improved the average daily gain of Hu sheep, reduced the feed cost, improved the apparent digestibility of DM, CP and NDF, and improved the meat quality and serum biochemical indexes. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.  相似文献   

18.
This study evaluated the effects of dietary concentrate level and chromium methionine(Cr-Met)supplementation on ruminal fermentation and fatty acid composition, and ruminal bacteria abundance in Tan lambs. Forty male Tan lambs [(21.00±1.23) kg body weight, 5 months of age] were randomly assigned to four treatment groups with 10 lambs in each treatment. The treatments were: a low-concentrate (LC) diet (concentrate:forage, 35:65) without Cr-Met supplementation; a high-concentrate (HC) diet (concentrate:forage, 55:45) without Cr-Met supplementation; groups fed the HC diet with 0.75 or 1.50 g·d-1·lamb-1 Cr-Met (HCM and HCH, respectively). Ruminal fluid was collected on day 65 with an oral stomach tube about 3 h after the morning feed and samples used for fermentation analysis, fatty acid composition determination and bacterial DNA extraction. It was found that: 1) Ruminal pH, acetate proportion and acetate:propionate were greater (P<0.05) with the LC diet whereas microbial crude protein, propionate and valerate proportions were greater (P<0.05) with the HC diet. The acetate:propionate was greater (P<0.05) in the HCM group than in the HC group. 2) For the HC diet, the DNA abundances of Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) and Ruminococcus flavefaciens were decreased (P<0.05), compared with the LC diet, whereas the DNA abundance of Anaerovibrio lipolytica was increased (P<0.05). For lambs fed the HC diet, DNA abundances of B. fibrisolvens stearic acid subgroup, Butyrivibrio VA, Butyrivibrio proteoclasticus, and A. lipolytica showed a linear decrease (P<0.05) with increasing Cr-Met supplementation level; However, the DNA abundance of R. flavefaciens showed a linear increase (P<0.05). 3) Compared with the LC group, the concentrations of t11 C18:1, trans C18:1, c9t11 CLA, t10c12 CLA, C18:2n6, and C18:3n3 were decreased by the HC diet without Cr-Met supplementation whereas the concentration of C18:0 was increased. There was a linear increase in t11 C18:1 and trans C18:1 with increasing Cr-Met supplementation level in lambs fed the HC diet. The results suggest that the HC diet inhibited the growth of ruminal bacteria involved in the ruminal biohydrogenation process, and the addition of Cr-Met had a potentially positive effect on conjugated linoleic acid (CLA) synthesis in body tissue. © 2022, Editorial Office of Acta Prataculturae Sinica. All rights reserved.  相似文献   

19.
Background:Galacto-oligosaccharides(GOS)have been shown to modulate the intestinal microbiota of suckling piglets to exert beneficial effects on intestinal function.However,the modulation of intestinal microbiota and intestinal function by GOS in intestinal inflammation injury models has rarely been reported.In this study,we investigated the effects of GOS on the colonic mucosal microbiota composition,barrier function and inflammatory response of lipopolysaccharides(LPS)-challenged suckling piglets.Methods:A total of 18 newborn suckling piglets were divided into three groups,the CON group,the LPS-CON group and the LPS-GOS group.Piglets in the LPS-GOS group were orally fed with 1 g/kg body weight of GOS solution every day.On the d 14,piglets in the LPS-CON and LPS-GOS group were challenged intraperitoneally with LPS solution.All piglets were slaughtered 2 h after intraperitoneal injection and sampled.Results:We found that the colonic mucosa of LPS-challenged piglets was significantly injured and shedding,while the colonic mucosa of the LPS-GOS group piglets maintained its structure.Moreover,GOS significantly reduced the concentration of malondialdehyde(MDA)and the activity of reactive oxygen species(ROS)in the LPS-challenged suckling piglets,and significantly increased the activity of total antioxidant capacity(T-AOC).GOS significantly increased the relative abundance of norank_f_Muribaculaceae and Romboutsia,and significantly decreased the relative abundance of Alloprevotella,Campylobacter and Helicobacter in the colonic mucosa of LPS-challenged suckling piglets.In addition,GOS increased the concentrations of acetate,butyrate and total short chain fatty acids(SCFAs)in the colonic digesta of LPS-challenged suckling piglets.GOS significantly reduced the concentrations of interleukin 1β(IL-1β),interleukin 6(IL-6),tumor necrosis factor-α(TNF-α)and cluster of differentiation 14(CD14),and the relative mRNA expression of Toll-like receptor 4(TLR4)and myeloid differentiation primary response 88(MyD88)in the LPS-challenged suckling piglets.In addition,GOS significantly reduced the relative mRNA expression of mucin2(MUC2),and significantly increased the protein expression of Claudin-1 and zonula occluden-1(ZO-1)in LPS-challenged suckling piglets.Conclusions:These results suggested that GOS can modulate the colonic mucosa-associated microbiota composition and improve the intestinal function of LPS-challenged suckling piglets.  相似文献   

20.
Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P 0.05); the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.  相似文献   

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