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1.
Early life intervention is important to shape the gut microbiome profiles of adult animals due to the tremendous alteration of diet components. Nevertheless, there is still no unified understanding about its long-term effects in lambs. In this study, sixty 20-day-old lambs were assigned into ewe-rearing (ER) and artificial-rearing (AR) treatments to evaluate the effects of AR strategy on ruminal microbiota, fermentation, and morphology of pre-weaning lambs (from 20 to 60 days of age) and its long-term effects in the fattening stage (from 61 to 180 days of age). During the pre-weaning stage, ER lambs were breastfed and supplemented starter, while AR lambs were artificially fed with milk replacer and starter. During the fattening stage, all lambs in both treatments were fed with the same fattening diets. At 60, 120 and 180 days of age, 6 lambs from each group were slaughtered to collect rumen content and tissue samples. Compared with ER lambs, the dry matter feed intakes of AR lambs increased (P<0.05) from 20 to 180 days of age, companying an increased average daily gain (ADG) from 61 to 120 days of age (P<0.05) and from 121 to 180 days of age (0.05<P<0.1). Although there was no difference in short-chain fatty acid (SCFA, including acetate, propionate, and butyrate) between treatments before weaning (P>0.05), it was higher (P<0.05) in AR lambs compared with ER lambs at the fattening stage. The rumen keratin layer of AR lambs was thinner (P<0.05) than that of ER lambs. Along with lamb growth from 60 to 180 days of age, the differences in rumen bacterial diversity between AR and ER treatments grew more distinct (P<0.05). Compared with ER lambs, AR lambs increased (P<0.05) rumen bacteria abundance, such as phylum Spirochaetes and genus Treponema at 60 days of age, phylum Actinobacteria and genus Succiniclasticum at 120 days of age, and phylum Proteobacteria at 180 days of age, but decreased genus Selenomonas from 60 to 180 days of age, and Anaerovibrio at 180 days of age. In summary, the early interventions before weaning could improve dry matter feed intake of lambs, which triggered robust rumen development and produced positive long-term effects on rumen fermentation and noticeable weight gain of fattening lambs. It suggests that the artificial rearing strategy is effective in improving rumen fermentation and microbial maturity of intensive fattening lambs.  相似文献   

2.
Although fungal communities in the gastrointestinal tract have a significant role in animal health and performance, their dynamics within the tract are not well known. Thus, this study investigated fungal community dynamics in the rumen and rectum of lambs from birth to 4 mon of age by using IT1S rDNA sequencing technology together with the RandomForest approach to determine age-related changes in the fungal ecology. The results indicated that gastrointestinal fungal community composition, diversity, and abundance altered (P<0.05) with the increasing age of the lambs. Two phyla, Ascomycota and Basidiomycota, dominated the samples. Similarity within age groups of the rumen fungi increased sharply after 45 days of age, while the similarity increased (P<0.05) significantly after 60 days of age in the rectum. The age-related genera, Acremonium, Microascus, Valsonectria, Myrmecridium, Scopulariopsis, Myrothecium, Saccharomyces, and Stephanonectria, were presented in both ruminal and rectal communities, and their changes in relative abundance were consistent at both sites. The principal coordinates analysis showed significant differences (P<0.05) between the fungal communities in the rumen and rectum. Our findings demonstrate that both the age of lambs and the gastrointestinal tract region can affect the composition of these fungal communities, and this provides new insight and directions for future studies in this research area.  相似文献   

3.
采食不同组合全饲粮颗粒料羔羊的瘤胃液代谢参数   总被引：9，自引：3，他引：9  
将40只陶塞特(♂)与藏羊(♀)的杂交一代羔羊(4～4.5月龄,公、羯各半)按同质原则分为4组。预试期(21天)后的50天中,各组试羊分别喂以按2×2析因设计的4种等营养水平、不同组合精料型的全饲粮颗粒料。从各组分别选出6只羊,于饲养试验结束后连续两天采集不同时段的瘤胃液样,测定了其中pH值、NH3-N和VFA含量。结果表明:⑴ 各组羔羊不同时段瘤胃液pH值多在6.30～7.5之间,食后速降,5 h后恢复弱碱性;NH3-N含量变化类似于pH值;此二指标的变化似可说明饲喂间隔4 h的合理性。⑵ 各组羔羊瘤胃发酵均为高丙酸型,乙酸为41.72 %～44.60 % TVFA,丙酸为36.77 %～43.43 % TVFA,有采食含小麦饲粮(A1)丙酸比例较食含甜菜渣饲粮(A2)高的趋势。⑶ 食A1羔羊瘤胃液pH值呈低于食A2者的趋势,食含大豆粕饲粮(B1)羊瘤胃液pH值下降幅度也呈高于食含菜籽粕饲粮(B2)的趋势;瘤胃液NH3-N的组间差异亦有类似趋势。  相似文献   

4.
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5.
【目的】研究饲粮中添加胍基乙酸和甜菜碱对羔羊生长性能、瘤胃发酵及血清生化指标的影响,为胍基乙酸和甜菜碱在反刍动物生产中的应用提供理论依据。【方法】试验选用48只体重相近(22.03±1.30)kg、3月龄左右的杜泊×小尾寒羊杂种公羔,采用2×2因子完全随机试验设计,试验因素为胍基乙酸(guanidineacetic acid,GAA)(0或900 mg·kg-1)和甜菜碱(betaine,BT)(0或5 g·d-1)。试验羔羊随机分为4组,每组12只。分别为对照组、GAA组、BT组和GAA+BT组。试验期共75 d,其中预试期15 d,正试期60 d。正试期第1天晨饲前称量体重作为初始体重(IBW),正试期内记录每只羊的日采食量、剩料量;正试期结束当日晨饲前先采血后空腹称重,作为终末体重(finwal body eight,FBW),计算平均日增重(ADG)、平均日采食量(ADFI)和饲料效率(FE);血清用于肌酸代谢指标、同型半胱氨酸(Hcy)和乳酸含量测定。试验结束当天正常饲喂试验羊,3h后采集瘤胃液,测定瘤胃发酵参数、消化酶活性以及功能...  相似文献   

6.
In a completely randomized block design experiment, 16 ruminally cannulated male sheep with body weights of (40 ± 2.1) kg were fed twice daily (8:00 and 16:00) with concentrate and forage (50:50 on dry matter (DM) basis). Dietary treatments were supplemented with intraruminal doses of powdered Yucca schidigera extract (YSE) at the levels of 0 (control), 100, 200 and 300 mg · kg−1. On days of 15, 16 and 17 after feeding, ruminal content was sampled at 0, 2, 4, 6 and 8 h after dosing (8:00), and blood samples were collected at the end of experiment (the days 18 and 19 after feeding). Results showed that the treatment groups’ acidity was not affected (P = 0.13) by YSE. Comparing to the control, the ruminal propionate concentration was increased by YSE addition in a dose-dependent manner by up to 29.8% (P < 0.05), and the acetic concentration was decreased by up to 17.5% (P < 0.05). The ruminal ammonia concentration 2 hours after feeding was higher (P < 0.05) in sheep fed without YSE (increased by 17.57 mg· 100 mL−1) than those fed with YSE at 200 mg · kg−1 (6.77 mg · 100 mL−1 increase in NH3) and at 300 mg · kg−1 (6.50 mg· 100 mL−1 increase in NH3). Protozoal populations in the rumen were lower (P < 0.05) with the YSE feeding dose at 300 mg · kg−1 than the control. The serum chemistries were not different among treatments (P > 0.05) and were within the normal physiological ranges for sheep 19 days after feeding. The study indicated that 200 mg· kg−1 and 300 mg· kg−1 YSE groups had particular suppressing effects on ruminal ammonia concentration, ammonia-N concentrations and protozoal populations. The effect of YSE on ruminal fermentation could be attributed to the selective inhibitory effect on rumen microbial species. High level (300 mg · kg−1) YSE as feed additives resulted no negative impact on sheep in our tests.  相似文献   

7.
The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages, growth, digestion, rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages. Banana pseudostem silage was prepared either conventionally without any additives(CON) or mixed with 0.6% formic acid(F), 10% corn flour(C), or both(F+C). Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50(dry matter(DM) basis). A total of 48 Nubian black castrated goats(body weight(BW),(22.64±1.82) kg; 4-mon-old) were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design. Each group was fed on one of the four experimental diets for 40 days. A factorial arrangement of treatments of 2(formic acid levels: 0 and 0.6%)×2(corn flour: 0 and 10%) was adopted. Formic acid supplementation increased(P0.05) average daily gain, as well as lactic acid, propionate and butyric acid and water-soluble carbohydrate concentrations, but decreased(P0.05) the feed conversion rate, p H value, acetate/propionate ratio, and butyric acid concentration relative to the CON group. Corn flour supplementation increased(P0.05) the apparent digestibility of crude protein, neutral detergent fiber, and non-fibrous carbohydrate and Fibrobacter succinogenes, Ruminococcus albus, and Butyrivibrio fibrisolvens populations, but decreased(P0.05) the Ruminococcus flavefaciens population relative to the CON group. There were no F×C treatment interactions(P0.05) for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate(NFC)(P0.05). The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility, and regulating ruminal fermentation and bacteria populations.  相似文献   

8.
The objective of this study was to observe the forage yield, silage fermentative quality, anthocyanin stability, and antioxidant activity during the storage period and in vitro rumen fermentation of anthocyanin-rich purple corn (Zea mays L.) stover (PS) and sticky corn stover (SS). Forage yield of corn stover was weighed and ensiled with two treatments: (1) hybrid sticky waxy corn stover (control), and (2) hybrid purple waxy corn stover (treatment). Samples were stored in mini-silos for periods of 0, 7, 14, 21, 42, 63, 84, and 105 d. The results showed that PS had significantly higher (P<0.05) yields of dry matter (DM), organic matter (OM), gross energy (GE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and total anthocyanins than that of the SS. Anthocyanin-rich purple corn stover silage (PSS) showed higher (P<0.05) levels of DM and CP relative to the sticky corn stover silage (SSS). Although anthocyanin-rich PSS displayed a lower (P<0.05) level of pelargonidin-3-glucoside (P3G), it had higher (P<0.05) levels of peonidin (Peo) and pelargonidin (Pel) compared to the control. Delphinidin (Del) and malvidin (Mal) were not detected in SSS during the ensilage period; in PSS, Del was no longer detected after 7 d of ensilage. Specifically, total anthocyanins in anthocyanin-rich PSS decreased rapidly (P<0.05) prior to 7 d of ensilage, and then remained at relatively stable (P>0.05) constants. Compared to the anthocyanin-rich PSS, SSS displayed significantly higher (P<0.05) pH value and ammonia nitrogen (NH3-N) content. Propionic acid (PA) at 0 d and butyric acid (BA) during the entire study period were not detected, whereas anthocyanin-rich PSS showed a higher (P<0.05) level of lactic acid (LA) than that of the SSS. Compared with the SSS extract, anthocyanin-rich PSS extract showed a higher (P<0.05) level of 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and displayed a lower (P<0.05) half maximal inhibitory concentration (IC50) value. Moreover, anthocyanin-rich PSS reduced (P<0.05) gas production (GP), and displayed lower levels of immediately soluble fraction and ratio of acetic acid (AA) to PA at 12 h, but the other parameters were unaffected (P>0.05) relative to the control. Taken together, the results indicated that: (1) anthocyanins could be stable in silage; (2) anthocyanin-rich PSS showed better silage fermentative quality and stronger antioxidant activity; and (3) anthocyanin-rich PSS had no negative effect on rumen fermentation parameters.  相似文献   

9.
【目的】研究高精料饲粮条件下,添加不同水平葡萄籽原花青素（GSPs）对杜寒杂交羔羊生长性能、瘤胃发酵、瘤胃及血清炎症因子及抗氧化能力的影响。为葡萄籽原花青素在反刍动物生产中的应用提供数据参考。【方法】选择48只体重相近（22.75±1.20 kg）、月龄相近的杜泊×小尾寒羊杂交公羔,采用单因素完全随机试验设计,将48只羔羊随机分为4组,每组12只。基础饲粮精粗比为7:3,GSPs添加量分别为0（对照组,CON）、10（10GSPs）、20（20GSPs）、40（40GSPs）mg·kg-1 BW。饲养期共60 d,前15 d为预饲期。正试期第1天晨饲前称量体重作为初始体重。正试期结束后颈静脉采集血液并分离血清,用于抗氧化指标、炎性因子和脂多糖含量测定;同时每组随机选择6只分别于饲喂后1、3、4、6、8、12 h口腔采集瘤胃液,立即测定瘤胃液pH,饲喂后3 h瘤胃液样品用于测定发酵指标及脂多糖含量。每组剩余6只进行屠宰,采集瘤胃组织测定抗氧化指标和炎症因子水平。【结果】10GSPs和20GSPs组的末体重显著高于对照组（P<0.05）,与40GSPs组差异不显著（P>0.05）。10GSPs和20GSPs组ADG和ADFI显著高于对照组和40GSPs组（P<0.05）,而40GSPs组与对照组差异不显著（P>0.05）;添加GSPs对瘤胃pH有一定的调控作用,饲喂后3、8、12 h瘤胃pH随GSPs添加水平增加而线性升高（P<0.05）,4 h瘤胃pH较对照组有线性升高趋势,但差异不显著（P=0.057）;添加GSPs后瘤胃液中乙酸、丁酸、总挥发性脂肪酸浓度有降低的趋势（P<0.1）,对丙酸、异戊酸、戊酸浓度及乙酸/丙酸值没有显著影响（P>0.05）;添加GSPs后血清脂多糖浓度较对照组显著降低（P<0.05）,但不影响瘤胃液中脂多糖浓度。20GSPs和40GSPs组瘤胃组织GSH-Px活性显著高于对照组和10GSPs组,MDA含量显著低于对照组和10GSPs组（P<0.05）。20GSPs和40GSPs组血清SOD活性显著高于对照组,GSH-Px活性显著高于对照组和10GSPs组（P<0.05）。添加GSPs对瘤胃组织炎症因子没有显著影响,但有降低IL-6和IL-10的趋势（P<0.1）。20GSPs和40GSPs组血清TNF-α水平显著低于对照组和10GSPs组（P<0.05）;40GSPs组血清IL-10含量显著低于对照组（P<0.05）,与10GSPs和20GSPs组差异不显著（P>0.05）。【结论】高精料饲粮条件下补饲适量GSPs可以提高羔羊瘤胃pH,提高血清和瘤胃组织抗氧化能力,对羔羊健康具有潜在的保护效应。在本试验条件下,GSPs的最佳饲喂量为20 mg·kg-1BW。  相似文献   

10.
试验采用4×4拉丁方设计,观察其4种粉碎粒度豆粕(细粉豆粕、中粉豆粕、未粉豆粕和粗粉豆粕)对绵羊瘤胃发酵和豆粕瘤胃外流速度(铬标记方法)的影响。试验结果表明,不同粉碎粒度豆粕对瘤胃液pH没有显著影响。瘤胃NH3-N浓度具有随着豆粕粉碎粒度增大而降低的趋势,但统计差异不显著。细粉豆粕在瘤胃中的分解速度快于粗粉和未粉豆粕(P>0.05),未粉豆粕组NH3-N浓度在采食6h后比其它3组低10.35%~15.60%,而粗粉豆粕组瘤胃NH3-N浓度在采食8h后比其它3组高6.28%~13.07%。细粉豆粕、中粉豆粕、未粉豆粕和粗粉豆粕通过瘤胃的速度分别为每小时5.8%、4.5%、5.0%和4.8%,前3组羊粪中Cr2O3浓度高峰出现时间为饲喂后40h,而粗粉豆粕在44h。未粉豆粕在瘤胃中的外流速度适中,而蛋白质分解量较少,未粉豆粕可直接利用在反刍动物生产中。  相似文献   

11.
为研究添加不同水平的柴胡提取物对热应激条件下泌乳后期荷斯坦奶牛营养物质表观消化率和瘤胃发酵参数的影响,采用随机区组设计,按照产奶量、泌乳天数及胎次相同的原则将48头荷斯坦奶牛随机分为4组,每组12头,各组在基础日粮中分别添加0、0.5、2.5和5.0g/kg柴胡提取物(干物质基础),试验期9周。结果表明:热应激条件下,柴胡提取物对瘤胃pH,氨氮含量,丙酸、异丁酸、丁酸、异戊酸和戊酸浓度,乙酸/丙酸及营养物质表观消化率均无显著影响(P0.05);0.5g/kg组的菌体蛋白含量显著高于2.5和5.0g/kg添加组(P0.05),添加5.0g/kg柴胡提取物降低瘤胃总挥发性脂肪酸(P=0.05)和乙酸浓度(P=0.06),不利于瘤胃发酵。因此,柴胡提取物推荐添加剂量不宜超过5.0g/kg。  相似文献   

12.
为了研究冬季补饲对妊娠期藏母羊瘤胃挥发性脂肪酸(volatile fatty acid,VFA)、微生物区系及羔羊生长发育影响.采用单因子试验设计,随机选择健康藏母羊440只,分为2组.对照组(control check,CK)为放牧饲喂,处理组(test,T)在放牧基础上,每只母羊补饲0.1 kg·d-1精料补充料,试验期为45 d(配种后106～150 d).试验结束后,从处理组和对照组中随机选择5只和6只母羊屠宰后分析瘤胃挥发性脂肪酸和细菌菌群组成.同时测定新生羔羊的生长发育指标.结果 表明:(1)处理组羔羊的体重、体高和胸围显著高于对照组(P＜0.05);(2)处理组瘤胃液总挥发性脂肪酸(Total volatile fatty acids,TVFA)、丙酸和丁酸含量显著高于对照组(P＜0.05),同时乙酸和异丁酸显著低于对照组(P＜0.05);(3)两组母羊瘤胃微生物在门和属水平上组成相似,拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)以及疣微菌门(Verrucomicrobia)为优势菌门;而普雷沃菌属-1(Prevotella l)、理研菌科RC9肠道群(Rikenellaceae-RC9-gut-group)、普雷沃氏菌科-UCG-001(Prevotellaceae-UCG-001)为优势菌属;(4) Alpha多样性指数中,对照组的Shannon指数显著高于处理组(P＜0.05),说明对照组瘤胃微生物多样性优于处理组;(5)瘤胃微生物功能预测发现,两组母羊瘤胃微生物主要富集于复制和修复(Replication and Repair)、碳水化合物代谢(Carbohydrate Metabolism)和信号转导(Signal Transduction).综上,妊娠后期藏母羊的冬季补饲能够为胎儿的生长发育提供必要的营养需求,同时提高母羊瘤胃液中TVFA、丙酸和丁酸含量,但在一定程度上影响了瘤胃细菌的多样性.  相似文献   

13.
为研究集约化饲养模式下巴美肉羊与小尾寒羊的生长性能、屠宰性能及肉品质指标,试验选择4月龄体况良好、体重相近的巴美肉羊和小尾寒羊公羔各10只,按品种分为2组,饲喂以精粗质量比为50∶50(干物质基础)的全混合日粮(TMR)。测定各试验羊饲养120d期间的相关生长性能指标和相关屠宰性能及肉品质指标。结果表明:1)巴美肉羊的干物质采食量、试验末体重、总增重和日增重均极显著高于小尾寒羊(P0.01);2)巴美肉羊宰前活重(P0.01)、热胴体重(P0.05)和眼肌面积(P0.05)均显著高于小尾寒羊,而屠宰率则显著低于小尾寒羊(P0.01);3)巴美肉羊背最长肌宰后45min的pH(P0.05)、宰后1h的红色度(a*)和黄色度(b*)(P0.01)以及宰后24h的红色度(a*)(P0.05)等指标均显著高于小尾寒羊,而巴美肉羊背最长肌的剪切力、滴水损失和蒸煮损失等指标显著低于小尾寒羊(P0.05)。由此可见,在以TMR日粮为主要饲喂方式的集约化饲养模式下,巴美肉羊比小尾寒羊能发挥更高的生产性能并生产出品质更佳的羊肉。  相似文献   

14.
张春桃  马涛  屠焰  刁其玉 《中国农业科学》2022,55(18):3664-3674
【目的】生物钟系统普遍存在于生命体的各级水平,与动物本身的消化生理及生长性能存在着密切的内在关联。试验探讨了昼夜节律与湖羊瘤胃发酵参数和养分消化代谢的关联,以期为提高育肥羊生长性能和营养物质的利用率提供依据。【方法】选用体重为(21.57±0.77) kg 健康湖羊45只,随机分为3个处理组,每组15只,各处理组采用相同的精料补充料和粗料。3个处理分别设置为：白天处理组（DH),即早上饲喂日总精料的70%+日总粗料的30%;晚上处理组(DL),即早上饲喂日总精料的30%+日总粗料的70%;对照组(CON),即早上和晚上各饲喂日总精料的50%+日总粗料的50%。饲喂两个月后,进行消化代谢试验。采用全收粪、尿法用于测定养分表观消化率和代谢率。饲养试验结束后,分别于晨饲前两小时和晚饲前2h,通过口腔采集瘤胃液样本用于相关指标测定。【结果】①试验羊只的日增重DH组为215.00g,进食量低于DL组和CON组,饲料转化比最优,为5.35,分别优于其他2组11.19 %和16.04 %。②与CON相比,DH组羊只干物质 (DM)、有机物 (OM)、粗蛋白 (CP)、中性洗涤纤维 (NDF)和酸性洗涤纤维 (ADF)消化率均高于CON 和DL组,具体：DH与DL组相比,DM消化率提高了21.42%,CP提高了22.29%,NDF提高了9.85%,ADF提高了28.69%。③氮的生物学价值DH组比CON明显提高（P>0.05）各组间可消化氮的摄入量之间无显著差异,DL组试验羊的总氮排出显著高于DH组（P<0.05）。DH组羊沉积氮、氮利用率和氮的生物学价值显著高于DL组（P<0.05）和CON组（P>0.05）。④不同处理对各组试验羊瘤胃微生物蛋白(MCP)、乙酸、和总挥发性脂肪酸(TVFA)等指标差异不显著（P>0.05）,DH组羊只瘤胃pH、乙丙比、丁酸显著低于DL组（P<0.05）。随着昼夜交替变化,瘤胃pH、NH3-N、乙酸、丙酸、总挥发性脂肪酸和乙丙比发生显著变化（P<0.05）,相关参数值白天高于夜间。【结论】在相同日粮营养素含量条件下,改变早、晚精粗料比的分配,可提高羊只生长性能和养分的消化利用率;白昼与夜间对瘤胃发酵有影响,白天饲喂高精料日粮对瘤胃TVFA、NH3-N和MCP含量具有促进作用。总之,早上适量提高精料比例,更符合动物机体的消化和吸收的节奏,对饲料的利用效果更佳。  相似文献   

15.
为研究植物蜕皮甾酮、大蒜提取物、苍术提取物、桑叶提取物和牛蒡子提取物对瘤胃体外发酵的影响,试验利用体外产气量法设对照组(未添加组)和5个试验组,每种植物提取物的添加水平为1.5%,测定了发酵24和48h的DM消化率以及发酵96h的发酵参数。结果显示:1)和对照组相比,各试验组24hDM消化率无显著性差异(P0.05),植物蜕皮甾酮和大蒜提取物组48h的DM消化率显著高于对照组(P0.05);2)各植物提取物对96h产气量、理论最大产气量以及产气速率均无显著性影响(P0.05);3)各组之间pH无显著性差异(P0.05);植物蜕皮甾酮、桑叶提取物和苍术提取物组的NH3-N浓度显著低于对照组(P0.05);植物蜕皮甾酮和桑叶提取物显著降低了总挥发酸浓度(P0.05),而牛蒡子提取物显著提高了总挥发酸浓度(P0.05);各提取物均降低乙酸摩尔比,升高了丙酸的摩尔比,但差异不显著(P0.05)。添加上述提取物能够降低体外发酵NH3-N浓度、提高48hDM消化率,可以一定程度的改善瘤胃发酵模式。  相似文献   

16.
Grain-induced subacute ruminal acidosis (SARA) impairs rumen epithelial barrier function, but it is yet to be determined if SARA can cause persistent damage to the morphology and function of the rumen epithelial barrier. The objective of the present study was to investigate if SARA has persistent effects on the morphological structure and permeability of ruminal epithelium and the expression of the genes involved in epithelial barrier function using a lactating goat model. Twelve mid-lactating Saanen goats with rumen cannulas were randomly assigned to 1 of 2 groups: control group (Ctrl, n=4) fed a basal diet with a non-fiber carbohydrate (NFC) to neutral detergent fiber (NDF) ratio of 1.40, and SARA group (SARA, n=8) fed the same basal diet but with increasing NFC to NDF ratio from 1.4 to 1.79, 2.31, and 3.23 overtime to induce SARA. At the end of the SARA challenge (post-SARA), 4 goats were randomly selected from the SARA group and fed only hay mixture adlibitum for another 4 weeks to allow for restitution (post-SARA). Ruminal pH was continuously recorded to monitor the severity of SARA. Samples of the ventral ruminal epithelium were collected after slaughter to examine the structural and functional changes of the ruminal epithelium using transmission electron microscopy (TEM), Ussing chambers, qRT-PCR, and Western bolt analyses. Compared with the Ctrl group, ruminal papilla length, width, surface area and thickness of stratum corneum increased (P<0.05), while stratum spinosum and basale thickness, and total depth of the epithelium decreased (P<0.05) in the SARA group. These changes diminished or tended to return to the levels of the Ctrl group in the post-SARA group (P>0.05). The SARA challenge also decreased cellular junction and widened the intercellular space between epithelial cells. Rumen transepithelial short-circuit current (Isc), tissue conductance (Gt), and mucosa-to-serosa flux of paracellular horseradish peroxidase (HRP) all increased (P<0.05) both in the SARA and post-SARA groups, which indicates that SARA can induce a sustained increase in epithelial permeability and barrier dysfunction. Moreover, the mRNA and protein expressions of CLDN1, OCLN and ZO-1 were down-regulated (P<0.01) in both the SARA and post-SARA groups. The results of this study showed that SARA could result in sustained epithelial barrier dysfunction, at both structural and functional levels, which is associated with decreased expression of rumen epithelial tight junction proteins, and the restitution of rumen epithelial barrier function is slower than that of its morphology.  相似文献   

17.
Eight Chinese Holstein cows were used in a 4 × 4 Latin square design to determine the effects of rumen protected methionine (RPMet) and Niacin on milk yield and milk composition of lactating cows with 14 d adaptation and 6-d sampling periods. The cows were fed the control diet or the control diet plus RPMet (25 g·−1), niacin (6 g·−1), or RPMet (25 g·−1) + niacin (6 g·−1). The results showed that RPMet supplementation in the diet increased 4% fat corrected milk (FCM) yield (P < 0.05) and milk fat percentage (P < 0.05). However, supplemental RPMet had no effect on the solid non fat (SNF) (P > 0.05) and lactose percentage (P > 0.05). Dietary niacin supplementation increased milk yield (P < 0.05), milk protein percentage (P < 0.05) and lactose percentage (P < 0.05), but had no effect on milk fat percentage (P > 0.05) and SNF (P > 0.05). RPMet supplementation in the diet of lactating cows significantly decreased serum urea nitrogen (P < 0.01) and glucose contents (P < 0.05), but had no effects on nonesterified fatty acids (NEFA), total cholesterol and triglyceride (P > 0.05). Niacin supplementation influenced the contents of glucose and NEFA in serum, but had no effects on the urea nitrogen, total cholesterol and triglyceride (P > 0.05).  相似文献   

18.
Isolated ruminal epithelia from caudal blind sacs of dairy goats were incubated with butyrate and insulin-like growth factor-1 (IGF-1) at different concentrations. Proportions of ruminal epithelium in different phases of the cell division cycle were determined by flow cytometric analysis. The proportion of epithelial cells in S phase and G2-M phase (PS&G2-M) increased significantly (P<0.01) whereas the proportion of epithelial cells in G0-G1 phase (PG0-G1) decreased after incubation with IGF-1. PS&G2-M decreased whereas PG0-G1 increased markedly (P<0.01) after incubation with sodium butyrate. PS&G2-M incubated with IGF-1 and butyrate sodium together increased more than that incubated with IGF-1 alone; PG0-G1, however, decreased significantly (P<0.01). Our results indicate that IGF-1 enhances whereas sodium butyrate inhibits the proliferation of rumen epithelial cells. Furthermore, butyrate and IGF-1, together, have a synergic effect on the proliferation of rumen epithelium.  相似文献   

19.
The present study was conducted to evaluate the effect of dietary mulberry(Morus alba L.) leaves powder(MLP) supplementation on meat quality of finishing pigs.A total of 40 Duroc×Landrace×Yorkshire pigs(initial body weight of(40.5±0.63) kg) were randomly allotted into two treatments,fed either with control diet or 15% MLP diet for 85 d.The results showed that MLP diet decreased(P≤0.05) average daily gain(ADG) and increased(P0.05) feed/gain ratio(F/G) in the finishing and whole period.MLP diet also decreased(P0.05) carcass weight,dressing percentage,last rib and average backfat depth.However,MLP diet increased(P0.05) intramuscular fat(IMF) content,decreased(P0.05) shear force,cooking loss and drip loss.In addition,MLP diet increased(P0.05) total antioxidative capacity,glutathione peroxidase and tended(P0.10) to increase total superoxide dismutase in serum.In longissimus thoracis,myosin heavy chain(MyHC) I and IIa mRNA levels were increased(P≤0.05) for MLP diet.In conclusion,15% MLP supplementation reduced the growth performance and carcass traits,but improved meat quality of finishing pigs possibly through the change of myofiber characteristics,enhancement of antioxidative capacity and increase of IMF.  相似文献   

20.
Five lactating Holstein cows in a 5×5 Latin square experiment were fed five high-concentrate total mixed rations(TMRs) to investigate the effects of step-wise improvement of forage combination on ruminal and milk fatty acid profiles. The ratio of concentrate to forage was fixed as 61:39, and the step-wise improvement of forage combination was applied as: TMR1, a ration containing corn stover; TMR2, a ration containing corn stover and ensiled corn stover; TMR3, a ration containing ensiled corn stover and Chinese wild ryegrass hay(Leymus chinensis); TMR4, a ration containing the ryegrass hay and whole corn silage; TMR5, a ration containing the ryegrass hay, whole corn silage and alfalfa hay. The TMRs were offered to the cows twice daily at 0700 and 1900 h. The entire experiment was completed in five periods, and each period lasted for 18 days. Diurnal samples of rumen fluids were collected at 0100, 0700, 1300 and 1900 h(day 16); 0300, 0900, 1500 and 2100 h(day 17); and 0500, 1100, 1700 and 2300 h(day 18). The step-wise improvement of forage combination increased energy and crude protein contents and decreased fibre content. As a result, the step-wise improvement of forage combination increased dry matter intake and milk yield(P0.05). The step-wise improvement increased dietary content of linolenic acid(C18:3 n-3), but did not alter dietary proportions of palmitic acid(C16:0), stearic acid(C18:0), oleic acid(C18:1 cis-9), linoleic acid(C18:2 n-6) and arachidic acid(C20:0). In response to the forage combination, ruminal concentration of C16:0, C18:2 n-6 and C18:3 n-3 linearly increased against their dietary intakes(P0.10). The step-wise improvement increased milk contents of C10:0, C12:0, C14:0, C16:0, C18:2 n-6 and C18:3 n-3(P0.10) and decreased milk contents of C18:0 and C18:1 cis-9(P0.05). Milk yields of C16:0, C18:1 cis-9, C18:2 n-6 and C18:3 n-3 were linearly increased by the increase of these fatty acids in the rumen(R2≥0.79, P0.05), and milk yields of C18:2 n-6 and C18:3 n-3 were also positively correlated with dietary intake of these fatty acids(R2≥0.85, P0.05). The step-wise improvement increased the transfer efficiencies from feed to milk for C18:2 n-6 from 11.8 to 14.2% and for C18:3 n-3 from 19.1 to 22.3%. In a brief, along with the step-wise improvement of forage combination, more dietary linoleic and linolenic acids might escape microbial hydrogenation in the rumen and consequently accumulated in milk fat though these fatty acids were present in low concentrations in ruminal fluids. The step-wise improvement of forage combinations could be recommended as a dietary strategy to increase the transfer efficiency of linoleic and linolenic acids from feed to milk.  相似文献   

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