喷淋与吹风对热应激肉牛生产性能及生理指标的影响

摘要

【目的】研究喷淋与吹风对热应激肉牛生产性能及生理指标的影响。【方法】选用30头体质量、月龄和日增质量相近的西门塔尔杂交肉牛,随机分为A（对照组）、B（间歇性喷淋吹风组）、C（吹风组）3组,进行47d（预试期7d,正试期40d）的环境调控试验,每日定时测定畜舍内外的温、湿度和试验牛只的基本生理指标,定期测定每头试验牛只的采食量和体质量,并进行经济效益分析。【结果】1）与A组相比,B、C 2组14：00时肉牛的呼吸频率均极显著降低（P〈0.01）,其中B组的降低幅度最大;14：00时3组肉牛的直肠温度没有显著差异（P〉0.05）,但B、C 2组14：00直肠温度的升高幅度较05：30时有所降低。2）B组的日均采食量比A组极显著提高了19.55%（P〈0.01）,比C组提高了6.67%（P〉0.05）;C组比A组显著提高了12.07%（P〈0.05）。平均日增质量方面,B组比A组显著提高了18.52%（P〈0.05）,比C组提高了5.79%（P〉0.05）,C组比A组提高了12.04%（P〉0.05）。3）B、C 2组的头日毛盈利比A组分别提高了13.08%和7.99%。【结论】炎热夏季,在肉牛舍进行间歇性喷淋吹风和吹风,可不同程度地缓解肉牛的热应激,提高肉牛的经济效益,且以间歇性喷淋吹风的效果最佳。%【Objective】 The study was conducted to determine the effects of sprinkling water and fanning on physiological indices and growth performance of heat-stressed beef cattle.【Method】 Thirty crossbred beef cattle with similar body weight and age were divided into control group A（no sprinkling water or fanning）,experimental group B（interval sprinkling and fanning from 12：00-04：10 pm daily）,experimental group C（only fanning from 12：00-04：10 pm daily）.The temperature humidity index of cowshed and basic physiological indices of beef cattle were measured at fixed time everyday for 47 days（pre-experiment 7 days,experiment 40 days）,feed intake and body weight were regularly measured as well.Economic profit of each group was calculated at the end of experiment.【Result】 1） The respiratory rate（at 02：00 pm）of group B and C were extremely lower than that of the group A（P0.01）,while the rectal temperature showed no significant difference among the three groups（P0.05）,but compared with group A,the rectal temperature increase range decreased in group B and C between 02：00 pm and 05：30 am.2）Compared with group A and C,the average daily feed intake of group B increased by 19.55%（P0.01）,6.67%（P0.05）,respectively;and the average daily feed intake of group C was significantly increased by 12.07%（P0.05） than that of the group A.3）In contrast to group A and C,the average daily gain of group B increased by 18.52%（P0.05）,5.79%（P0.05）,respectively;and the average daily gain of group C significantly increased by 12.04%（P0.05） than that of the group A.4） Compared with group A,the economic profit（per head per day） of group B and C increased by 13.08%,7.99%,respectively.【Conclusion】 Alternate sprinkling and fanning and fanning can relieve the effect of heat stress on beef cattle and increase economic profit of beef cattle production in different degrees,and the effect of alternate sprinkling and fanning is more prominent.