Avaliação da eficácia dos diluidores tris ou água de coco em pó (ACP-106®), associado à Aloe vera (Aloe barbadensis Miller), na conservação de sêmen canino

Abstract

The aim was to evaluate the effect of the Aloe vera gel (Aloe barbadensis Miller), in association with the Tris base (hydroxymethyl aminomethane) or powdered coconut water (ACP- 106®) in canine semen conservation, as well as the action of this gel in the renewal process of the extender. Semen samples from five dogs, of breed Basset Hound, were used. In Experiment 1, samples were diluted in duplicate, using Tris plus 20% egg yolk (G1 and G2) or 5% Aloe vera (G3 and G4) and evaluated at 0, 48, 72 and 96 hours. After 48 hours, all samples were centrifuged for 10 minutes (400g) in a cooled centrifuge (5 °C). In the groups G1 and G3 the supernatant was removed and a new extender was added. In the other groups (G2 and G4) pellets were re-diluted in the same supernatant, without renewal. For Experiment 2, samples were divided into two equal aliquots, according to the treatments (G1: Tris + 20% egg yolk, control G2: Tris + 5% Aloe vera; G3: ACP-106® + 5% Aloe vera) and evaluated at 0, 24, 48 and 72 hours after cooling. In both experiments were performed sperm kinetics and membrane integrity analysis (iMP). In Experiment 1 results the diluent renewal did not affect on any parameter analyzed in the group using egg yolk (G1), shown when comparing the two treatments of this substance. The G2 (without renewal) did not demonstrate a significant difference when compared to G1 (renewal). However, groups with Tris-Aloe vera (G3 and G4) were lower (P <0.05) than the groups with Tris-egg yolk (G1 and G2) after the renewal, and this has showed deleterious effect on the group that sperm received new diluent (G3) in all parameters. There were no statistical differences in Experiment 2 in the parameters of total motility, straightness and oscillation index and plasma membrane integrity comparing treatments and evaluation times. However, the progressive motility in G1 proved to be significantly higher (P <0.05) than the other treatments in the first assessment period (0h). However, at 24 the G3 showed values similar to G1. The linearity values of G3 were significantly higher (P <0.05) than other groups from the start of the evaluations. According to the findings from Experiment 1, it can be concluded that the replacement of diluent is not necessary for the preservation of canine spermatozoa undergo cooling (5 °C) for 96 h. Furthermore, it was found that the gel of Aloe vera may be used to replace egg yolk in dog semen cooling diluent at a concentration of 5% without renewal. In the Experiment 2, it can be concluded that Aloe vera can be used at a concentration of 5% to replace egg yolk in dog semen cooling diluent, regardless of the one used.