Effects of extenders on the quality and fertility of cooled Formosan sambar stag semen after artificial insemination

Chih-Hua Wang, Hsin-Hung Lin, Shann-Ren Kang, Ching-Yun Kuo, Wen-Lin Song, Chin-Hui Tseng, Mu-Jung Cheng, Bing-Tsan Liu, and Perng-Chih Shen

　　The aim of this study was to examine the effects of extenders on the quality and fertility of cooled Formosan sambar stag semen after artificial insemination. Result showed that the sperm motility score (SMS), sperm concentration, and sperm viability (VIAB) of Formosan sambar stag semen collected by electro-ejaculation were 4.7, 8.9×108 sperms/mL and 87.0%, respectively. The SMS of semen diluted with TCY or TY extenders were not decreased by cooling at 4℃ for 12 h (5.0 and 5.0), but those of semen diluted with CY extender were decreased from 5.0 to 4.0. The VIAB (TCY: 86.8 vs. 89.3%; TY: 88.1 vs. 92.1%; CY: 84.2 vs. 88.3%) and acrosomal integrity (NAR) (TCY: 82.3 vs. 86.5%; TY: 82.5 vs. 88.5%; CY: 77.3 vs. 85.4%) of the semen diluted with TCY, TY or CY extenders and cooled at 4℃ for 12 h were significantly lower than those of semen freshly diluted with these extenders without cooling storage (0 h). The pregnant rates (TCY: 70%; TY: 80%; CY: 60%) and parturient rates (TCY: 70%; TY: 80%; CY: 60%) were similar among estrus synchronized Formosan sambar hinds after artificial insemination with the stag semen diluted with TCY, TY or CY extenders cooled at 4℃ for 12 h. In conclusion, Formosan sambar stag semen diluted with TCY or TY extenders has a better sperm quality. Despite of the extender used, the pregnant rate and the parturient rate after AI using the cooled semen were not affected.