author(s)
LJ Dutta, KC Nath, BC Deka, D Bhuyan, P Borah, GK Saikia, DP Bora, R Deka, C Acharya and D Bharali

abstract
A study was conducted to compare the efficacy of GnRH and GnRH fortified with bypass fat, minerals and vitamins for treatment of true anoestrus in crossbred cows based on oestrus induction response, post treatment conception rate and blood biochemical constituents. Per cent response to different treatment regimen in terms of manifestation of external signs of oestrus was recorded as 83.33, 50.00 and 83.33 for supportive, GnRH and GnRH + supportive treatment groups respectively. The corresponding post treatment oestrus intervals for the cows under the three treatment groups were 10.60 ± 2.11, 12.67 ± 7.31 and 5.00 ± 1.05 days and the conception rates were 50.00, 50.00 and 50.00 per cent. As regards to blood biochemical constituents studied in true anoestrus crossbred cows it could be mentioned that serum levels of most of the minerals (phosphorus, iron and zinc); reproductive hormone (Oestrogen) and metabolic hormones (leptin, ghrelin and IGF-1) were not found to vary significantly following treatment with different regimens. It can be concluded that Supportive treatment was found to be effective as GnRH in addressing true anoestrus in crossbred cows.