Efecto de la centrifugación coloidal previo al proceso de crio conservación sobre la calidad seminal post descongelación en caninos

Abstract

The objective of the investigation was to evaluate the colloidal centrifugation as a method of sperm selection plus the addition of glycerol in three concentrations 4%, 6% and 8% as cryoprotectant. We evaluated 72 seminal samples from 6 mestizo dogs, healthy, CC 5 (scale 1 to 9), from 3 to 5 years old, whose ejaculates met the following parameters: minimum volume 1ml, mass motility 3 (scale 1 to 5), Individual progressive motility 60% and less than 30% of abnormalities. Each sample was divided into 2 aliquots, the first for Group 1 (conventional centrifugation) and the other for Group 2 (colloidal centrifugation), after which each aliquot was divided into three, corresponding to the concentration of glycerol. Three sperm evaluations were performed (initial, pre-freezing and post-thawing). The comparative analysis between the initial samples and Groups 1 and 2 pre-freezing presented statistical differences (P <0.05) for the concentration, being lower in Group 2 (183x106), as for the progressive individual motility (MIP) reduced in Group 1 (61.3%); the vitality and the percentage of abnormalities did not show statistical differences (P> 0.05), between groups. It was determined that adding glycerol to 4%, improves cryopreservation expressed in a higher MIP (76.7%), as well as a lower percentage of abnormalities (4.3%) and greater vitality (93.6) post thawing, this when the seminal sample was centrifuged previously in colloidal medium. In conclusion, the use of the colloidal medium contributes to improve the selection of spermatozoa that together with a cryoprotectant based on glycerol to 4% allows to maintain the minimum parameters after thawing of the seminal sample in canines.