Avaliação do uso da gema de ovo de galinha (Gallus gallus domesticus) e galinha-d’angola (Numida meleagris) em diferentes proporções na criopreservação de espermatozoides caprino

Abstract

The present study aimed to evaluate the use of egg yolk from different bird species: hen (Gallus gallus domesticus) and guinea fowl (Numida meleagris), in proportions of 10%, 15% and 20%, in protocols of caprine sperm cryopreservation. Six ejaculates from 4 Saanen and Alpine goats were collected twice a week for threeconsecutive weeks. After collection and formation of the seminal pool, the semen was divided into six aliquots, centrifuged at 600 g for 10 minutes and resuspended directly inthe test media, adjusted to a final concentration of 400 million spz/mL, packaged in strawsof 0.25 mL, refrigerated and frozen in nitrogen vapour, using tested and standardized curves. Immediately after the formation of the seminal pool, after semen dilution and after freezing, evaluations of motility, vigor, test of structural and functional integrity of sperm membranes and sperm morphology were performed. The influence of semen processing (p<0.05) was verified, with a gradual reduction in the percentage of motility,in vigor, in the percentage of cells with structural and functional integrity of the membranes, as well as in the percentage of morphologically normal spermatozoa in all stages (in natura, post- dilution and post-freezing). Between treatments, there was no influence (p>0.05) of the bird species used as yolk supplier (hen and guinea fowl), nor between the proportions of yolk used, in all stages of the evaluations performed. We conclude that it is possible to replace chicken egg yolk with guinea fowl egg yolk in goatsemen cryopreservation protocols.