Evaluation of semen quality parameters and sperm kinematics in three wool sheep breeds in conditions of high tropics in Colombia

Abstract

This study aimed to evaluate the effect of the ejaculate, race, and sperm collections on semen quality and kinematic parameters in three wool sheep breeds in conditions of high tropics in Colombia. Semen was collected from 12 males of Creole, Romney marsh, and Hampshire sheep breeds ranging from 2 to 5 years of age, with artificial vagina, during 4 collections with a time of abstinence of 3 days. Motility analysis was performed with the help of a computer-assisted semen analysis (CASA) in combination with a fluorescent Hoechst 33259 stain for the study of viability and morphology. An analysis of measures repeated over time was performed with the SAS statistical package, using the Proc Mixed method. There were no significant differences (p > 0.05) in the percentage of total motility and progressive motility for the first and second ejaculates, but there were differences (p < 0.05) for concentration, volume, and viability the first ejaculate was significantly superior to the second, independent of breed and collection. Sperm kinematic variables related to progressive movement and speed (ALH, VAP, LIN) do not differ between ejaculates, but there is a racial effect (p > 0.05), since the Creole breed is superior in all these variables, which could suggest that the sperm cells of this breed have the ability to travel greater distance in less time, compared with sperm from the other two breeds, under the conditions of the present experiment.