Evaluación cuali-cuantitativa de espermatozoides de la cola del epedídimo de cuyes cavia porcellus criollos y mejorados en dos edades reproductivas

Abstract

EPIDÍDIMO.

ABSTRACT The objective of this research was to evaluate the qualitative and quantitative characteristics of sperm extracted from the caudal epididymis of creole guinea pigs and improved in two reproductive ages. Was conducted at the farm Irquis in the Cuenca´s University in 20 breeding male guinea pigs identified by their phenotypic characteristics and arranged in four groups: 5 young native (NY), 5 adult native (NA), 5 youth improved (YI), and 5 adults improved (AI). The animals were hemi castrated and epididymis were dissected in their tail on a petri dish. Sperm recovered by Swim up, diluted in 1 ml medium (18% raffinose and 3% skim milk), processed by Triladyl®, cooled to 5 °C/1 hour, and equilibration time by 0, 2, 24, 48, 96, 192, and 360 hs for analysis of sperm viability. Only frozen sperm of 2 hs of equilibration time in vapors liquid nitrogen. A DCA (2x2) was used: phenotype and age, and ANOVA test was used to significance. Interaction (P <0.05) between factors was obtained, obtaining higher values in Improves, at 0 hs in C and Total abnormalities tail (AaT), at 24hs at motility progressive (IMP), and at 48hs at vitality (V). In total abnormalities (AT) only found differences (P <0.05) at 0 hs (MJ: 26.3; CJ: 32.6; MA: 36.2; CA: 38.5%); and AaT differences (P <0.05) at 0 hs (:; 9.5; CA: 11.5; MA: CJ 4.6 MJ 16.4%) was found, and 48 hs (CA 5.7; CJ: 7.3; MJ: 16.0; MA: 18.1%). In membrane integrity (HOS-Test) was obtained (P <0.05) differences at 2 hs (MJ: 20.0; MA 13.1, CA 10.7; CJ: 9.0%) and 96 hs (CA: 25.4; CJ: 15.3; MJ: 9,7; MA: 8.8%). In the analysis of freezability not sperm survival was obtained in any treatments. In conclusion, the quantity and quality epididymal sperm of guinea pigs identified according to their phenotype varies with age; but could not check their variation in freezability to be quite susceptible to cryopreservation.