Effect on Pregnancy Rates of Injected Lecirelin Acetate (GnRH analogue) after Insemination in the Cows

In the present study the effects of lecirelin acetate injections applied in different ways after artificial insemination on the pregnancy rate of cows were investigated. As a material, 180 cows showing the spontaneous oestrus between 50-120 days after parturation and having the sexual cycle at regular intervals and showing no clinical disorders during the treatment process were used. The cows were randomly divided into 4 groups as A, B, C and D. In the group A (n = 50) 50 μg lecirelin acetate was injected to the sacrococcygeal epidural space of the animals immediately after the artificial insemination . The animals in the group B (n = 40) were injected with 2 ml physiological saline solution by the same route applied to the animals in the group A. The animals in the group C (n = 50) were injected with 50 μg lecirelin acetate intramuscularly immediately after the artificial insemination. The animals in the group D (n = 40) were injected with 2 ml physiological saline solution by the same route applied to the animals in the group C. Statistically significant in difference (P <0.05) were observed between the pregnancy rates of groups A and B (64%) and (45%). It was detected that there was no significant difference (P>0.05) in the pregnancy rates of the groups C and D (60% and 52,5%, respectively). In addition, no significant difference (P>0.05) was observed between the group A (applied epidural GnRH) and C (applied intramuscular GnRH). As a result, it was concluded that either intramuscular or epidural administration of Lecirelin Acetate to cows showing spontaneous oestrus can be used after artificial insemination to increase the pregnancy rates