Treatment of cystic ovarian disease in the dairy cow with 50, 100 or 250 micrograms of gonadotropin-releasing hormone (GnRH, LHRH).

The present study examined the effect of three dose levels of LHRH (50, 100 and 250 micrograms) for the treatment of cystic ovarian disease in lactating dairy cows. The main results are given in Table I. A total of 52 cows were treated; 14 cows with 50 micrograms of LHRH, 24 with 100 micrograms, and 14 with 250 micrograms. No statistically significant differences were found in the clinical response between the 3 treatment groups. Compared to the reproductive performance of the rest of the herd, in which the study took place, the reproductive performance after treatment indicated a good overall response to treatment. Progesterone analyses performed on milk or plasma on the day of treatment in 28 cases (Table II) revealed that 25% of the treated cows had elevated levels of progesterone in milk or plasma on the day of treatment. Progesterone "profiles" based on 4 samples in 5 cows (Figure 1) indicated that unnecessary retreatments may, to some extent, have been performed in this study.