| With the development of animal husbandry in the direction of scale and factory,animal welfare and healthy farming have become important measures to improve the economy of livestock products.As one of the five large cattle breeds in China,Qinchuan cattle has the characteristics of delicious meat and strong resistance.In this experiment,the metabolic control cabin was used to control the behavior of 12-month-old Qinchuan cattle with similar body weight and temperature at different temperatures of-5°C,20°C,30°C,and 40°C.Growth performance,blood biochemistry and other indicators were tested,which is intended to provide theoretical basis and technical support for the comfortable temperature of Qinchuan cattle.1:Effect of temperature on behavior of Qinchuan cattleThrough careful observation and counting of the behavior of Qinchuan cattle,the statistical results showed that the feeding time,feeding frequency and feeding speed of Qinchuan cattle at 40°C were significantly lower than at 20°C（P<0.05）.Qinchuan cattle in the ruminant behavior,the chewing time and chewing times of Qinchuan cattle at 40°C decreased significantly than at 20°C,and the ruminant time at 40°C increased significantly than at 20°C（P<0.05）.There was a significant difference in chewing time between-5°C and 20°C（P<0.05）.The average daily drinking water and urination frequency at 40°C increased significantly than at 20°C（P<0.05）.The exercise behavior of Qinchuan cattle at-5°C and 40°C decreased significantly than at 20°C.The rest behavior of Qinchuan cattle at-5°C and 40°C decreased significantly than at 20°C（P<0.05）.The daily weight gain of qinchuan cattle at-5°C was significantly lower than that at 20°C（P<0.05）.Qinchuan cattle showed negative weight gain at 40°C,and significant difference with 20°C（P<0.05）.2:Effect of temperature on physiology and biochemistry of Qinchuan cattleIn the feeding process,the blood of Qinchuan cattle was extracted under different temperature conditions,and the physiological and biochemical indexes were detected.The results showed that there were significant differences in body temperature（head,abdomen and back）of Qinchuan cattle at different temperatures（P<0.05）.Compared with 20°C,the respiratory rate,heart rate and rectal temperature were significantly increased at 40°C and30°C（P<0.05）.Among the biochemical results,the contents of GLU,TP,ALB and TC at40°C,5 d were significantly increased at 20°C,but the BUN content was significantly decreased（P<0.05）.In the endocrine index,the contents of T3 and T4 on 3 d,5 d at 40°C was significantly decreased at 20°C,but the content of Cort was significantly increased（P<0.05）.The content of K+,Ca2+and Cl-in serum inorganic ion content at 40°C was significantly different from that at 20°C（P<0.05）;Among the enzyme activities,ALT,CK,CK-MB and LDH at 40°C were significantly lower than those at 20°C on the 5th day（P<0.05）.The results of antioxidant index,which the SOD at 40°C was decreased significantly than at 20°C on the 5th day,but the MDA increased significantly（P<0.05）.In the immune index,the IgA,IgG,IgM at 40°C was significantly reduced at 20℃on the 5th d,HSP70 was significantly increased（P<0.05）.3:Effect of temperature on reproductive performance of Qinchuan cattleEffects on the reproductive performance of Qinchuan cows and bulls:according to the test results,when the temperature exceeds 30°C,the cow’s estrus rate,ovulation rate,conception rate,bull’s semen volume,total sperm count,sperm motility,was significantly lower than that at 15-25°C（P<0.05）.After incubated granulosa cells at 40°C for 12 h,the cell viability was significantly lower than that at 37°C（P<0.05）.In summary,the high temperature environment has a great adverse effect on the growth performance,behavior,physiological and biochemical indexes,antioxidant index,endocrine index and reproductive performance of Qinchuan cattle.When the ambient temperature is as low as-5°C,there is no significant effect on Qinchuan cattle.Therefore,in the breeding process of qinchuan cattle,measures should be taken to prevent heatstroke. |
