Mefepronic acid, a PPAR agonist, is inefficient on reproductive performance of ewes in both early and late postpartum period

Abstract

The liver is a dynamic organ that plays critical roles in many physiological processes. In farm animals, supporting the liver reduces postpartum metabolic diseases and loss of reproductive and milk yield in transition period. The aim of this study is to investigate the effects of mefepronic acid (2-methyl-2-phenoxy propionic acid) injection on reproductive performance parameters with short-term progestagen administration in early and late postpartum period Hungarian Merino ewes during the non-breeding season. In the study, 89 adult ewes in the early (n=45) and late (n=44) postpartum (pp) period were used in the study. Control and treatment (MA) groups were formed separately for each pp period. Following insertion of vaginal sponge containing 60 mg medroxyprogesterone acetate for 7 day, PMSG 500 IU was injected intramuscularly (day 7) to all ewes. In treatment groups (Early MA and Late MA), 10 mg/kg mefepronic acid (Hepagen®, Fatro Güneşli) was injected (day 7), and remaining ewes consisted of control groups (Early Control and Late Control). The estrus signs of the ewes were followed and they were hand-mated (ewe: ram=5:1). Pregnancies were determined with transabdominal real time B-Mode ultrasonography with convex probe (3.5 MHz) on day 45 post-mating. There were no statistical differences in estrus rate, pregnancy rate, lambing rate and litter size at 1st service, 2nd service and overall services in early and late pp groups. According to results of this study, administration of mefepronic acid to ewes in the early and late pp period had no increasing effect on reproductive parameters. However, further studies investigating the survival of embryos and prostaglandin metabolism are needed to determine the efficacy of mefepronic acid in ewes.