动物营养学报2017，Vol.29Issue(9)：3120-3131,12.DOI:10.3969/j.issn.1006-267x.2017.09.013
热应激对不同品种(系)青年肉牛生产性能、营养物质表观消化率及血液生化指标的影响
Effects of Heat Stress on Performance, Nutrient Apparent Digestibility and Blood Biochemical Indices of Different Breeds of Young Beef Cattle
摘要
Abstract
This experiment was conducted to investigate the effects of heat stress on performance,nutrient apparent digestibility and blood biochemical indices of different breeds of young beef cattle,in order to explore the heat resistance difference of different breeds of beef cattle.Six individuals of Simmental crossbred cattle (Simmental cattle×Xuanhan yellow cattle),indigenous yellow cattle (Xuanhan yellow cattle) and cattle yak (Maiwa yak×Jersey cattle) were chosen based on similar body weight [(185.89±14.02) kg].Animals were fed with the same diet and feeding experiment lasted 187 days,including 7-days adaption period and 180-days test period.The experiment from April 2015 to September 2015.The results showed as follows: 1) the temperature humidity index (THI) of barn was above 72 from May to August and this stage belonged to heat stress (HS) period,and the THI of HS period was higher than April (pre HS) and September (after HS) (P<0.05).During the HS period,the respiratory frequency and rectal temperature were significantly increased (P<0.05) for all experimental animals.The respiratory frequency and rectal temperature of cattle yak was significantly higher than those of Simmental crossbred cattle and indigenous yellow cattle in the period of experiment (P<0.05).2) The dry matter intake per body weight of Simmental crossbred cattle,indigenous yellow cattle and cattle yak was decreased in HS period,and the lowest value in June and significantly lower than April (P<0.05),the degree of decreased was cattle yak>Simmental crossbred cattle>indigenous yellow cattle.The lowest values of average daily gains of Simmental crossbred cattle,indigenous yellow cattle and cattle yak were all in June,and decreased by 27.62% (P<0.05),10.81% (P>0.05) and 46.15% (P<0.05) as contrasted April,respectively.The average daily gain of Simmental crossbred cattle was significantly higher than that of cattle yak from April to July (P<0.05).The highest values of feed/gain of Simmental crossbred cattle and cattle yak in June,and increased by 63.01% (P<0.05) and 89.03% (P<0.05)as contrasted April,respectively;the highest value of feed/gain of indigenous yellow cattle in September,and increased by 53.12% as contrasted to April (P<0.05).3) The apparent digestibility of crude protein (CP) of Simmental crossbred cattle,indigenous yellow cattle and cattle yak was different degrees of reduction in HS period and significantly decreased in July compared with April (P<0.05).The apparent digestibility of ether extract (EE) of Simmental crossbred cattle was significantly decreased in July compared with April (P<0.05),but the HS had no significant effects on the apparent digestibility of EE for indigenous yellow cattle and cattle yak (P>0.05).The apparent digestibility of neutral detergent fiber (NDF) (June) and acid detergent fiber (ADF) (from May to August) of cattle yak was significantly decreased in HS period compared with pre HS (P<0.05).The apparent digestibility of calcium (Ca) of Simmental crossbred cattle (from June to August) and cattle yak (from May to August) was significantly decreased in HS period compared with pre HS (P<0.05),and the apparent digestibility of phosphorus (P) of Simmental crossbred cattle (from June to July) and cattle yak (from May to August) was significantly decreased in HS period compared with pre HS,too (P<0.05).During the experiment period,the apparent digestibility of CP had no significant difference among the three breeds of young beef cattle (P>0.05),the apparent digestibility of EE of Simmental crossbred cattle and indigenous yellow cattle was significantly higher than that of cattle yak (P<0.05),the apparent digestibility of ADF of indigenous yellow cattle was significantly higher than that of Simmental crossbred cattle and cattle yak (P<0.05),and the apparent digestibility of P of Simmental crossbred cattle and indigenous yellow cattle was significantly higher than that of cattle yak (P<0.05).Moreover,the apparent digestibility of Ca of indigenous yellow cattle was significantly higher than that of cattle yak from May to September (P<0.05).4) Serum glucose (GLU) concentration of Simmental crossbred cattle,indigenous yellow cattle and cattle yak had the lowest value in June and decreased by 16.82% (P<0.05),12.82% (P>0.05) and 15.90% (P<0.05) compared with April,respectively.For all the experimental cattle,the non-esterfied fatty acid (NEFA) concentration had the lowest value in July and significantly lower than that in April (P<0.05).Serum urea nitrogen (UN) concentration of Simmental crossbred cattle and indigenous yellow cattle was increased at first and then decreased in the experiment period with the age increasing,while the serum UN concentration of cattle yak was continually increased.Serum creatinine (CRE) concentration of all experimental animals in June to September was significantly higher than that in April and May (P<0.05),and the serum CRE concentration of cattle yak was significantly higher than that of indigenous yellow cattle from July to September (P<0.05).In conclusion,the performance and apparent digestibility of nutrients of different breeds of young beef cattle are decreased under heat stress condition.Indigenous yellow cattle are more tolerance of heat stress than Simmental crossbred cattle and cattle yak,and cattle yak are more sensitive to heat stress.关键词
热应激/肉牛/生产性能/营养物质表观消化率/血液生化指标Key words
heat stress/beef cattle/performance/nutrient apparent digestibility/blood biochemical indices分类
农业科技引用本文复制引用
蒲启建,王之盛,彭全辉,张灿,景小平,胡瑞,邹华围..热应激对不同品种(系)青年肉牛生产性能、营养物质表观消化率及血液生化指标的影响[J].动物营养学报,2017,29(9):3120-3131,12.基金项目
国家肉牛牦牛产业技术体系资金资助(CARS-38) （CARS-38）
