GONADOTROPHIN RELEASING HORMONE TREATMENT OF HOLSTEIN COWS WITH FOLLICULAR CYSTS MONITORED BY SKIM MILK PROGESTERONE DETERMINATION

Document Type : Original Article

Authors

Theriogenology Department, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt.

Abstract

Progesterone was assayed in skim milk fraction of 38 cystic cows, 26 (68.4%) of which had basal (<0.5 ng/ml) progesterone concentration and were diagnosed as having follicular cysts. These cows were allotted at random to one of 3 treatments: (1) a sham injection of sterile water in 7 cows as controls; (2) a single injection (1 mg) of GnRH analog in 8 cows; (3) double injections (1 mg) of GnRH analog at 7-day interval in all cows.  According to rectal palpation confirmed by skim milk progesterone determination, the double injection gorup responded well (P < 0.05) compared to the single injection and control groups (81.8% vs 62.5% vs 42.9%). The interval from calving to 1st insemination, interval from treatment to conception and interval from calving to conception were significantly (P < 0.01) shorter in the double-injection group than in the other 2 groups. Moreover, the conception rate to first insemination was significantly (P < 0.05) higher (63.6% vs 37.5% vs 42.9%). The data provide an evidence for reduction in infertility and reproductive disorders in cystic cows given double injections of GnRH.

Main Subjects