Kinetic and Morpho-Functional Analyses of Refrigerated and Cryopreserved Semen of 5/8 Girolando Bulls

Abstract

This study aimed to investigate the effects of refrigeration and cryopreservation on the sperm kinetic and morpho-functional parameters of 5/8 Girolando bulls. Eleven ejaculates from each bull were collected, diluted, and divided into two portions: one portion was subjected to refrigeration at 5ºC for 24 and 48 hours, while the second portion underwent cryopreservation(-196ºC). Post-thawing, various kinetic parameters were analyzed using the Computer Assisted Sperm Analysis (CASA) system. These parameters included total motility (TM), progressive motility (PM), curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), straightness coefficient (STR), wobble coefficient (WOB), amplitude of lateral head displacement (ALH) and beat cross frequency (BCF). Additionally, plasma membrane integrity (PMI), acrosomal membrane integrity (AMI), mitochondrial membrane potential (MMP), and chromatin condensation (CC) were examined for morpho-functional analyses. The results indicated that kinetic parameters (TM, PM, VCL, VSL, VAP) and morpho-functional analyses (PMI, MMP) differed significantly (P < 0.05) between cryopreserved and refrigerated semen, as well as other parameters such as LIN, ALH, and BCF across all groups. The acrosomal membrane integrity showed no differences, but CC varied significantly among all groups. In conclusion, semen from 5/8 Girolando bulls can be preserved for up to 48 hours at 5ºC, providing an alternative for the short-term use of genetic material from this breed.