Utilização do Caseinato de Sódio na Congelação de Sêmen Bovino

Abstract

Semen extender play important role in maintaining sperm quality and viability, as well as the ability to fertilize after cryopreservation process. The objective of this study was to evaluate the efficacy of sodium caseinate (2%) added to commercial diluent with 15% egg yolk (CG group), to maintain the fertility of cryopreserved bovine sêmen; as control, the same commercial diluent with 20% egg yolk without sodium caseinate was used (group G). In experiment 1, sperm kinetics, spermatozoa population without plasma and acrosomal membranes changes (IMPA), without membrane destabilization (SDM) and without membrane phosphatidylserine translocation (FTS), mitochondrial potential (APM) and superoxide generation (O2-) of thawed semen of both groups were evaluated In vitro fertilization test (cleavage rate on D3 and embryo rate in D8) and percentage of pregnancy by TFAI were performed in experiments 2 and 3 F. According to the results, there was difference in spermatic kinetics between groups, favoring GC (P <0.05), mainly after termal stress (T90). IMPA, SDM, FTS, differences were also observed in T90 in favor of GC (P<0.05) for three evaluations. However, the high mitochondrial potential (APM) and oxygen reactive species (EROS) were lower in T0 and T90 in GC (P <0.05). In vitro fertility test showed difference on D3 cleavage rate and on D8 embryos production (P <0.05), as well as in vivo fertility test by TFAI in favor of GC (P <0.05). It was concluded that there was improvement of sperm morphofunctionality and fertility both in vitro and in vivo of cryopreserved bovine semen with addition of 2% caseinate to the diluent.