Vol. 9, Special Issue 9 (2020)

Author(s):
K Senthilkumar, M Selvaraju, R Ezakial Napolean, B Mohan and M Palanisam

Abstract:
An experiment was conducted on serum cortisol level during winter and summer seasons in Tellicherry goats. Out of 240 Tellicherry does, 120 does during winter season and the remaining 120 does during summer season. The selected does of each season were divided into six experimental groups viz., Groups I, II, III, IV, V (Treatment groups) and VI (Control group). In Group I, the selected does were synchronized with intravaginal sponge method. In group II, all the does were treated with ovsynch protocol. In group III, does were treated with ovsynch protocol along with progesterone intravaginal sponge. The does of group IV were subjected to co-synch protocol which was similar to Ovsynch protocol except that breeding was done at the time of 2^nd GnRH injection. In group V, does were treated with Co-synch protocol along with progesterone intravaginal sponge. The does of group VI were observed for oestrus from the time of selection during each season and were bred by NS or AI during the observed oestrus. During winter and summer seasons there was a significant difference in the mean cortisol levels between pregnant and non-pregnant does at all stages of blood collection. At the time of breeding the cortisol level in non-pregnant does were significantly (P≤ 0.05) higher than pregnant does in all the groups.