RESUMO
BACKGROUND: The addition of the detergent Orvus ES Paste (OEP) to semen freezing extenders has been observed to improve the post-thaw survival and longevity of spermatozoa from various species but has never been evaluated for yak spermatozoa. OBJECTIVE: This study evaluated the effects of OEP on the post-thaw motility and viability of epididymal and ejaculated yak spermatozoa. MATERIALS AND METHODS: Semen samples were frozen and thawed in semen freezing extender supplemented with 0 %, 0.375 %, 0.75 % or 1.5 % OEP. The motility and viability of frozen-thawed spermatozoa were evaluated before and after 3 h of incubation. RESULTS: The addition of 0.75 % OEP to the freezing extender significantly improved the mean motility and viability values of both the epididymal and ejaculated spermatozoa immediately after thawing, but the beneficial effects on motility disappeared after 3h of incubation. CONCLUSION: Our findings indicate that the addition of 0.75 % OEP is effective for the preservation of yak spermatozoa.
Assuntos
Bovinos/fisiologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Detergentes/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides/citologia , Acrossomo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Epididimo/citologia , Epididimo/efeitos dos fármacos , Congelamento , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacosRESUMO
The chemical toxicity of cryoprotectants to porcine embryos was examined by the evaluation of survival and DNA damage after exposure to cryoprotectants. Porcine blastocysts were exposed to 10% of ethylene glycol (EG), 1,2-propanediol (PD) or glycerol (GLY) for 1 h at room temperature (23-25 degrees C) and then cultured in vitro for 24 h. The survival rates of blastocysts exposed to PD and GLY were significantly lower than those of control blastocysts in which the embryos were exposed to carrier solution without cryoprotectants. Significantly more DNA-fragmented nuclei occurred in the cryoprotectant-exposed blastocysts, compared with the control blastocysts. Moreover, the indices of DNA-fragmented nuclei in the blastocysts without blastocoele re-formation after culture were significantly higher than those with blastocoele re-formation, irrespective of the exposure treatment. These results indicate that the exposure of porcine blastocysts to cryoprotectant decreases the survival rates and increases the DNA-fragmented nuclei in embryos.