O uso de um novo diluidor para congelamento de sêmen de jumento na inseminação de fêmeas equinas com ovulação induzida

Abstract

This study was carried out in Lagoa Dourada county, Minas Gerais State, from December 2013 to March 2014, with the aim of propose, produce and utilize a new extender for freezing donkey semen, as part of a new protocol. Also, the pregnant rates of mares inseminated after detection of ovulation, induced by hCG, were evaluated. Those animals were submitted to a follicular control at every 8-hour interval after drug administration, when a follicle higher than 30-35mm diameter and uterine edema 2 were recorded. Two Pêga breed donkeys were used as semen donors. After collection, semen was frozen using two extenders: (1) glucose-skimmed milk powder (GSMP) egg yolk ethylene glycol (Jepsen, 2010) and (2) PIVO-2013. Mares were inseminated post-ovulation with frozen-thawed semen, from both extenders with an insemination dose of 5mL (300.00 x 106 338.89 ± 7,35 x 106 mobile spermatozoa / insemination dose), with deposition of semen inside the uterus body. The pregnant rates were 23.81% (5/21) and 55.56% (10/18), respectively, for extenders 1 and 2 (p<0,05), respectively. Seminal characteristics differed between donkeys, showing individual variation. The pregnant rates per donkey were 28.57% (6/21) and 50% (9/18), respectively, for donkeys 1 and 2. The administration of 1,666 IU of hCG was efficient to induce ovulation, being the majority of the ovulations observed within 30 to 40h after induction