Influence of the type of semen and morphology of individual sperm cells on the results of ICSI in domestic cats.

The aim of this study was to analyze the influence of the type of spermatozoa and of different sperm abnormalities on fertilization and embryo development after ICSI in cats. In Exp I, ICSI was performed using urethral or epididymal spermatozoa collected from 7 tomcats. In Exp. II, epididymal spermatozoa from 16 cats were used for ICSI and an epididymal spermatozoon exhibiting no abnormalities or one with an abnormality was microinjected into an oocyte. Exp. I was performed in 14 replicates and Exp. II was performed in 20 replicates. In both experiments the number of cleaved oocytes, the number of embryos at the morula stage and the number of embryos at the blastocyst stage were evaluated at 24 h, and at 6 and 7 days after ICSI, respectively, and compared between experimental groups. No statistically significant differences (P > 0.05) were observed, either for Exp. I or for Exp. II. The average cleavage rate was 60.2%, morula rate 62.3% and blastocyst rate 19.2% in Exp. I and 51.6%, 66.8% and 25.8% in Exp. II, respectively.