摘要
本试验旨在研究夏季热应激对肉牛血清生化指标、瘤胃发酵参数及微生物区系的影响。选取20头18月龄、体重为(330±20)kg的健康锦江牛,随机分为常温组和高温组,每组各10头牛,均饲喂基础饲粮。常温组与高温组分别饲养于春季适温环境和夏季高温高湿环境,预试期10 d,正试期30 d。结果表明:常温组的平均温湿指数(THI)为69.86,未受到热应激;高温组平均THI为83.40,属于中度热应激。与常温组相比,高温组肉牛体温有升高的趋势(P=0.080),呼吸频率显著升高(P<0.05);血清总抗氧化能力(T-AOC)显著降低(P<0.05),血清免疫球蛋白A(IgA)含量与谷胱甘肽过氧化物酶(GSH-Px)活性均极显著降低(P<0.01);瘤胃氨态氮(NH3-N)浓度显著升高(P<0.05),总挥发性脂肪酸(TVFA)含量极显著降低(P<0.01)。对试验牛瘤胃微生物组学采用16S rRNA测序技术分析发现,与常温组相比,在门水平上,高温组的放线菌门(Actinobacteriota)的相对丰度显著升高(P<0.05),脱硫杆菌门(Desulfobacterota)和Patescibacteria的相对丰度极显著升高(P<0.01);在属水平上,高温组的克里斯滕森菌科_R-7群(Christensenellaceae_R-7_group)、NK4A214_group和普雷沃氏菌科UCG-003(Prevotellaceae UCG-003)的相对丰度显著降低(P<0.05)。以上结果表明,夏季高温高湿环境可引起肉牛热应激,热应激引起肉牛体温、呼吸频率升高,抗氧化、免疫能力下降,瘤胃液挥发性脂肪酸含量下降,NH-N浓度升高,瘤胃纤维素分解菌丰富度降低,但不影响瘤胃细菌的多样性。
The aim of this study was to investigate the influence of summer heat stress on serum biochemical indexes,rumen fermentation parameters and microflora of beef cattle.Twenty healthy Jinjiang cattle,which aged 18 months and weighing(330±20)kg,were randomly divided into two groups,the normal and high temperature groups,with 10 cattle in each group,all fed the basal diet.The cattle in normal temperature group and high temperature group were raised in spring and a high temperature and humidity environment in summer,respectively,with a pre-test period of 10 day and a positive test period of 30 day.The results showed that the average temperature and humidity index(THI)of the high temperature group was 69.86,which was not subjected to heat stress,while the THI of the high temperature group was 83.40,which belonged to moderate heat stress.Compared with the normal temperature group,beef cattle in the high temperature group had a tendency to increase their body temperature(P=0.080)and their respiratory rate increased significantly(P<0.05);the serum total antioxidant capacity(T-AOC)decreased significantly(P<0.05),and the serum immunoglobulin A(IgA)content and glutathione peroxidase(GSH-Px)activity decreased significantly(P<0.01);ruminal ammonia nitrogen(NH3-N)concentration was significantly higher(P<0.05),total volatile fatty acid(TVFA)content was significantly lower(P<0.01).Profiling the microbiome of rumen using 16S rRNA sequencing,compared with the normal temperature group,at the phylum level,the relative abundance of Actinobacteriota was significantly higher in the high temperature group(P<0.05),the relative abundance of Desulfobacterota and Patescibacteria increased significantly(P<0.01);at the genus level,compared with the normal temperature group,the relative abundance of Christensenellaceae_R-7_group,NK4A214_group and Prevotellaceae UCG-003 was significantly decreased in the high temperature group(P<0.05).The above results show that the high temperature and high humidity environment in summer can cause the heat stress of beef cattle.Heat stress can increase the body temperature and respiratory rate of beef cattle,reduce the antioxidant and immune ability,reduce the VFA content,increase the NH-N concentration in rumen fluid,and reduce the richness of rumen cellulose decomposing bacteria,but does not affect the diversity of rumen bacteria.
作者
杨梓曼
尚相龙
陈豪
兰剑
聂春桃
陈环
瞿明仁
宋小珍
YANG Ziman;SHANG Xianglong;CHEN Hao;LAN Jian;NIE Chuntao;CHEN Huan;QU Mingren;SONG Xiaozhen(Jiangxi Provincial Key Laboratory of Animal Nutrition/Engineering Research Center of Nutritional Feed Development,College of Animal Science and Technology,Jiangxi Agricultural University,Nanchang 330045,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2022年第7期4487-4497,共11页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家自然科学基金项目(32060768)
现代农业产业技术体系资助项目(CARS-37)。
关键词
热应激
肉牛
血清生化指标
瘤胃发酵
瘤胃微生物区系
heat stress
beef cattle
serum biochemical indexes
rumen fermentation
rumen microflora
