PHYSIOLOGICAL RESPONSE OF CROSSBRED CALVES TO PRE-MONSOON, MONSOON AND POST-MONSOON SEASONS OF KERALA*

Abstract

A study was conducted to assess the adaptability of crossbred female calves inhabiting Mannuthy, Thrissur, Kerala. Seven crossbred female calves of six to twelve months of age were randomly selected from University Livestock Farm and Fodder Research and Development Scheme, Mannuthy, Thrissur. Physiological responses such as Rectal Temperature (RT), Respiratory Rate (RR), Heart Rate (HR) and Pulse Rate (PR) were recorded at 08:00-09:00 h and 13.00-14:00 hin pre-monsoon, monsoon and post-monsoon seasons. Meteorological data were also recorded on all the days of the experiment. There is a significant (p<0.05) increase in diurnal variation as indicated by elevated ambient temperature, relative humidity and THI from 08:00-09:00 h and 13.00-14:00 h in all the three seasons. Similarly RT, RR, HR and pulse rate increased significantly (p<0.05) with diurnal variation from 08:00-09:00 h and 13.00- 14:00 h in all the three seasons. This study indicates that all the animals were under heat stress in all the three seasons as evidenced by significant increase in RT, RR, HR and PR from forenoon to afternoon. It is concluded that the animals are trying to cope up with the heat stress by altering their physiological responses. But elevated RT during afternoon in all the three seasons indicates low thermal adaptability of the animals to the existing ambience

Keywords

• physiological responses
• adaptability
• crossbred calves
• season