Reproductive efficiency of asymptomatic Theileria equi carriers mares submitted to an embryo transfer program

Abstract

This study aimed to assess and evaluate the effects of Theileria equi infection on embryonic recovery, gestation and early embryonic loss. Thirteen Mangalarga Marchador Theileria equi positive donors (diagnosed through nested-PCR) and 40 embryos receptors were used. Donors were submitted to two embryo collections in two consecutive estrous cycles (GId); after, the same mares were treated with imidocarb dipropionate (1.2mg/kg IM.) in order to collect more embryos in two more estrous cycles (GIId). Receptors were divided into two groups (control and with treated) with 20 animals each, where one group was the control (GIr) and the other one (GIIr) treated with 1.2mg/kg IM of imidocarb dipropionate assessing the gestation rate at 15, 30, 45 and 60 days. After 52 embryo collections, the embryonic recovery rates were 53.84% (14/26) and 65.38% (17/26) (p > 0.05) for GId and GIId, respectively. The gestation rate was 70% (14/20) (p > 0.05) at 15, 30, 45 and 60 days in group GIr and for GIIr was 85% (17/20) (p > 0.05) at 15 days, 80% (16/20) (p > 0.05) at 30, 45 and 60 days. The treatment with imidocarb dipropionate did not cause significant improvement in the reproductive efficiency at an ET program.