中国农业大学学报2024，Vol.29Issue(1)：127-139,13.DOI:10.11841/j.issn.1007-4333.2024.01.12
去势和热应激对筠连黄牛生产性能、瘤胃发酵和血液生化指标的影响
Effects of castration and heat-stress on production performance,rumen fermentation and blood biochemical indexes of Junlian cattle
摘要
Abstract
The purpose of this study was to study the effects of castration and heat stress on production performance,rumen fermentation and blood biochemical indexes of yellow cattle.Eighteen 16-month-old Junlian yellow bulls of similar weight((292.35±28.71)kg)with different degree of castration(Full-castration group:FCG,hemi-castration group:HCG and sham-operation group:SOG)were selected and divided into three groups,with 6 replicates in each group and 1 bull in each replicate.Then divided into heat stress(July and August)and non-heat stress(September)periods according to the changes of the thermal-humidity index(THI)during the experiment.Then the impact of castration and heat stress on indicators of yellow cattle was analyzed The results showed as follows:1)Compared with the non-heat stress period,bulls in the heat stress period had significantly higher THI,respiratory rate and rectal temperature(P＜0.05).2)During the whole test period,the castration and heat stress significantly increased serum heat-shock protein 70,high-density lipoprotein(HDL-C),low-density lipoprotein(LDL-C)and estradiol concentrations(P＜0.05);while serum testosterone,thyroxine(T4),insulin,and free fatty acids concentrations were significantly decreased(P＜0.05);Besides serum glucose,T4 and LDL-C,castration and heat stress had a significant interaction effects on other serum index(P＜O.05).3)The full-castration and heat stress significantly decreased dry matter intake and average daily gain(ADG),and there was a significant interaction effect(P＜0.05).4)During the heat stress period,the castration significantly decreased crude protein,acid detergent fiber and Ca apparent digestibility,and serum total antioxidant capacity(T-AOC)(P＜0.05),but significantly increased T-AOC in the non-heat stress period(P＜0.05).5)The castration and heat stress both significantly increased rumen pH(P＜0.05),significantly decreased ammonia nitrogen(NH3-N),acetic acid(AA),and total volatile fatty acid(TVFA)concentrations(P＜0.05);and both had significant interaction effects on rumen pH,NH3-N,AA and TVFA concentrations(P＜0.05).In conclusion,castration and heat stress in bulls can affect the secretion of sex hormones concentrations and nutrient apparent digestibility,thereby reducing production performance,which provide a scientific basis for feeding management of beef cattle during heat stress periods.关键词
筠连黄牛/热应激/去势/生产性能/表观消化率/血液生化指标Key words
Junlian cattle/heat stress/castration/production performance/apparent digestibility/serum biochemical indexes分类
农业科技引用本文复制引用
岳子奇,邓文松,王成,左家学,姚小鹤,王之盛,胡瑞,邹华围,肖鉴鑫,左之才,彭全辉,梁秀容..去势和热应激对筠连黄牛生产性能、瘤胃发酵和血液生化指标的影响[J].中国农业大学学报,2024,29(1):127-139,13.基金项目
四川省科技计划项目(2021YFYZ0001) （2021YFYZ0001）
财政部和农业农村部:国家现代农业(肉牛牦牛)产业技术体系项目(CARS-37) （肉牛牦牛）
临沧市肉牛改良与产业化发展关键技术研究与示范项目(202104AC100001-A04) （202104AC100001-A04）
