Katiyatiya C L F, Bradley G, Muchenje V
Department of Livestock and Pasture Science, University of Fort Hare, Private Bag X1314, Alice 5700, Republic of South Africa.
Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, Republic of South Africa.
J Therm Biol. 2017 Oct;69:85-94. doi: 10.1016/j.jtherbio.2017.06.009. Epub 2017 Jun 29.
Boran (n=15) and Nguni (n=15) cows were used in a study to determine the effect of breed, age and coat colour on the concentration of heat shock protein 90 (HSP90AB1), physiological rectal and skin temperature, and markers of health. The cows were exposed to summer heat stress and Boran cows had higher significant (P<0.05) skin temperature (35.1±0.42°C) as compared to the Nguni cows (36.0±0.38°C). Nguni cows had higher body thermal gradients than the Boran cows. Boran cows had thicker skin (P<0.05) and longer hairs (24.3±2.26mm) than their Nguni counterparts (20.2±2.00mm). The HSP90AB1 concentration was increased in Boran cows, although breed had no significant (P>0.05) influence. Significantly (P<0.05) high urea and total cholesterol was recorded in Boran cows. Coat colour had a significant (P<0.05) effect on the weight and rectal temperature of the study animals. Coat colour and age had no significant effect (P>0.05) on the concentration of HSP90AB1, although older cows (≥9 years) had higher concentrations (5.4±1.29ng/ml). Age had a significant (P<0.05) effect on packed cell volume, neutrophil/lymphocyte, urea, total protein and gamma-glutamyl transferase whereas cows with ≥9 years had more concentrations than young ones. Age significantly (P<0.05) influenced hair length, skin temperature and the thermal gradients. Breed was positively correlated (P<0.001) to coat colour, age, body condition score, weight and temperature humidity index while negatively correlated to urea and total cholesterol. It was concluded that Nguni cows were more adaptable to hot environments than the Boran cows as the latter were unable to balance thermal load between their bodies and the environment.
在一项研究中使用了博拉牛（n = 15）和恩古尼牛（n = 15）来确定品种、年龄和毛色对热休克蛋白90（HSP90AB1）浓度、直肠和皮肤生理温度以及健康指标的影响。这些奶牛遭受夏季热应激，与恩古尼牛（36.0±0.38°C）相比，博拉牛的皮肤温度显著更高（P<0.05）（35.1±0.42°C）。恩古尼牛的身体热梯度比博拉牛更高。博拉牛的皮肤比恩古尼牛更厚（P<0.05），毛发更长（24.3±2.26毫米），而恩古尼牛的毛发长度为（20.2±2.00毫米）。尽管品种没有显著（P>0.05）影响，但博拉牛中HSP90AB1浓度有所增加。博拉牛的尿素和总胆固醇显著（P<0.05）偏高。毛色对研究动物的体重和直肠温度有显著（P<0.05）影响。毛色和年龄对HSP90AB1浓度没有显著影响（P>0.05），尽管年龄较大的奶牛（≥9岁）浓度更高（5.4±1.29纳克/毫升）。年龄对红细胞压积、中性粒细胞/淋巴细胞、尿素、总蛋白和γ-谷氨酰转移酶有显著（P<0.05）影响，≥9岁的奶牛这些指标的浓度高于年轻奶牛。年龄显著（P<0.05）影响毛发长度、皮肤温度和热梯度。品种与毛色、年龄、身体状况评分、体重和温度湿度指数呈正相关（P<0.001），与尿素和总胆固醇呈负相关。得出的结论是，恩古尼牛比博拉牛更能适应炎热环境，因为后者无法平衡身体与环境之间的热负荷。
