摘要
牦牛犊牛出生后,经历从采食液体饲料过渡到采食固体饲料、由非反刍营养型过渡到反刍营养型的转变。犊牛及早适应采食固体饲料对其生长和消化系统发育非常关键,是犊牛培育的重点。本试验旨在利用非靶向代谢组学技术探究固体饲料不同饲喂量对哺乳期牦牛犊牛胰腺发育的影响。选取日龄[(60±3)日龄]、体重[(54.20±3.28)kg]相近的21头健康的牦牛犊牛(公)作为试验动物,随机分为3组,即低饲喂量组(40%采食组,IR40组)、中饲喂量组(70%采食组,IR70组)和高饲喂量组(自由采食组,AL组),每组7头。3组试验犊牛均在饲喂等量代乳粉的基础上,分别采食低、中、高饲喂量的固体饲料(精料和苜蓿干草)。预试期30 d,正试期90 d。结果表明:1)AL组的体重、胰腺指数、外分泌部面积总占比显著高于IR70组(P<0.05);AL组的体重、胰腺重量、胰腺指数、外分泌部面积总占比显著高于IR40组(P<0.05)。2)AL组胰腺的胰淀粉酶、胰蛋白酶活性和胰岛素含量显著高于IR70组(P<0.05);AL组胰腺的胰淀粉酶、胰蛋白酶、糜蛋白酶活性和胰高血糖素、胰岛素、生长抑素含量显著高于IR40组(P<0.05);IR70组胰腺的胰高血糖素含量显著高于IR40组(P<0.05)。3)代谢组学分析发现,与AL组相比,IR70组在甾体生物合成中,麦角钙化醇含量显著上升(P<0.05);在卵母细胞减数分裂通路、孕酮介导的卵母细胞成熟通路和乳腺癌通路中,孕酮含量均显著上升(P<0.05);在嘧啶代谢通路中,脱氧胞苷酸、尿嘧啶含量显著上升(P<0.05)。与IR40组相比,IR70组在胰岛素抵抗通路中,UDP-N-乙酰葡糖胺含量显著下降(P<0.05);在甾体生物合成通路中,麦角钙化醇含量显著上升(P<0.05);在内分泌抵抗通路中,睾酮含量显著上升(P<0.05);在甘氨酸、丝氨酸和苏氨酸代谢通路中,O-磷酸-L-丝氨酸含量显著下降(P<0.05);在新霉素、卡那霉素和庆大霉素生物合成通路中,UDP-N-乙酰葡糖胺含量显著下降(P<0.05);在甾体激素生物合成通路中,科托酮、睾酮含量显著上升(P<0.05)。综上得出,采用代乳饲喂方式培育哺乳期牦牛犊牛时,提高固体饲料饲喂量改善了犊牛的生长发育质量,促进了其胰腺组织形态与功能的发育;且中饲喂量能够诱导哺乳期牦牛犊牛胰腺细胞分化,提升机体对小分子营养物质的消化吸收能力。
After the birth of a yak calf,the early adaptation of calves to solid feed is critical to their growth and digestive system development,as it involves the transition from liquid to solid feed and from a non-ruminant to a ruminant nutritional type.It is considered the focus of calf breeding.The aim of this experiment was to investigate the effects of different feeding levels of solid feed on the development of pancreas in suckling yak calves using non-targeted metabolomics techniques.Twenty-one healthy yak calves(males)with similar age[(60±3)days of age]and weight[(44.45±2.50)kg]were selected as test animals and randomly divided into three groups:the low feeding group(40%feed intake group,IR40 group),the medium feeding group(70%feed intake group,IR70 group)and the high feeding group(free feeding group,AL group),with 7 yak calves in each group.All three groups were fed equal amounts of milk replacer and different amounts of solid feed(concentrate and alfalfa hay).The pretest period lasted for 30 days,and the test period lasted for 90 days.The results showed as follows:1)the body weight,pancreatic organ index and total percentage of external secretory part area were significantly higher in the AL group than the IR70 group(P<0.05);additionally,the body weight,pancreatic weight,pancreatic organ index and total percentage of external secretory part area were significantly higher in the AL group than the IR40 group(P<0.05).2)Pancreatic amylase,pancreatic protease activity and insulin content were significantly higher in the AL group than the IR70 group(P<0.05).Moreover,pancreatic amylase,trypsin and chymotrypsin activities and glucagon,insulin and growth inhibitor contents were significantly higher in the AL group than the IR40 group(P<0.05);glucagon content was significantly higher in the IR70 group than the IR40 group(P<0.05).3)Metabolomic analysis revealed a significant increase in ergocalciferol content in steroid biosynthesis in the IR70 group compared with the AL group(P<0.05);progesterone content was significantly increased in the oocyte meiotic pathway,progesterone-mediated oocyte maturation pathway and breast cancer pathway(P<0.05);in the pyrimidine metabolic pathway,the contents of deoxycytidylic acid and uracil were significantly increased(P<0.05);the content of UDP-N-acetylglucosamine in the insulin resistance pathway was significantly decreased in the IR70 group compared with the IR40 group(P<0.05);the ergocalciferol content in the steroid biosynthesis pathway was significantly increased(P<0.05);the testosterone content in the endocrine resistance pathway was significantly increased(P<0.05);the O-phosphate-L-serine content in the glycine,serine and threonine metabolic pathways was significantly decreased(P<0.05);UDP-N-acetylglucosamine content was significantly reduced in the neomycin,kanamycin and gentamicin biosynthetic pathways(P<0.05);in the steroid hormone biosynthetic pathway,corticosterone and testosterone contents were significantly increased(P<0.05).In summary,it is concluded that when suckling yak calves are bred by milk replacer feeding,increasing the amount of solid feed improve the quality of growth and development of yak calves,and promote the development of the morphology and function of their pancreatic tissues;and the medium feeding amount can induce the differentiation of pancreatic cells in suckling yak calves,and enhance the body’s ability to digest and absorb small molecule nutrients.
作者
梁玉鸿
焦洋
刘书杰
杨得玉
周玉青
张万明
崔占鸿
LIANG Yuhong;JIAO Yang;LIU Shujie;YANG Deyu;ZHOU Yuqing;ZHANG Wanming;CUI Zhanhong(Key Laboratory of Plateau Grazing Animal Nutrition and Feed Science of Qinghai Province,Yak Engineering Technology Research Center of Qinghai Province,Key Laboratory of Animal Nutrition and Forage-Feed of Grazing Yak and Tibetan Sheep in Qinghai-Tibetan Plateau,Ministry of Agriculture and Rural Affairs,Academy of Animal Husbandry and Veterinary Sciences,Qinghai University,Xining 810016,China;Management Committee of Plateau Ecological Animal Husbandry Science and Technology Demonstration Park,Haibei Tibetan Autonomous Prefecture,Haiyan 810299,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2023年第12期7903-7919,共17页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家自然科学基金项目(32260853)
青海省中央引导地方科技发展资金项目(2023-ZY-017)。
关键词
哺乳期
牦牛犊牛
固体饲料饲喂量
胰腺发育
代谢组学
suckling period
yak calves
feeding level of solid feed
pancreas development
metabolomics
作者简介
梁玉鸿(1998-),女,贵州赤水人,硕士研究生,研究方向为反刍动物营养与饲料。E-mail:2383631828@qq.com;通信作者:崔占鸿,研究员,硕士生导师,E-mail:cuizhanhong27@126.com。
