Efeitos da centrifugação em coloide de camada única e de diferentes diluentes de congelamento sobre qualidade do sêmen equino

Abstract

This study aimed to evaluate the effect of a colloid in single layer centrifugation (AndroColl®-E; Minitub, Germany) associated to three freezing extenders: extender 1 (Botucrio®; Biotech, Botucatu,, Brazil), extender 2 (EquiPlus Freeze®; Minitub, Germany + 3% glycerol) and extender 3 (EquiPlus Freeze®; Minitub, Germany + 3% DMSO) on equine semen quality. We used three ejaculates from five stallion (n=15), collected by artificial vagina. After collection, the semen was diluted with extender to from skimmed milk (EquiPlus®, Minitub, Germany) and divided into 2 groups: group E (centrifuged without colloid) and group A (centrifuged with colloid). No grupo E, o sêmen foi centrifugado à 676g por 15 minutos, no grupo A, o sêmen foi centrifugado à 314g por 20 minutos. Após a centrifugação, os grupos receberam os diferentes diluentes: diluente 1, diluente 2 e diluente 3. The kinetics was evaluated by CASA and the integrity of plasma and acrossomal membrane by association of fluorescent probes and subjected to flow cytometry. With respect to the CASA parameters, it can be seen that the A1 group, with the colloid centrifuged, had superior result in LIN and WOB variables, compared to the E1 group. The variables, RAP, VCL, VAP, ALH and BCF, had lower results when centrifuged with colloid, A1 group than in the group E1. With respect to the integrity of plasma and acrosomal membrane, it can be seen that A1 and A3 groups were centrifuged with colloid, they had superior result to E1 and E3 groups, which were centrifuged without the colloid. The use of colloid improved integrity of plasma and acrosomal membranes probably avoided the process of sperm hyperactivation and provided lower production of ROS. Greater in vivo studies are needed to prove this technique.