Abstract: To study the effects of foot-and-mouth disease vaccine on sperm quality including the average collected volume, the average density, the average activity,the rate of semen abandon and the number of frozen semen tubules in bulls of different months. 30 bulls were divided into 3 groups according to their age and they were injected foot-and-mouth disease vaccine simultaneously. The results showed that after injecting foot-and-mouth disease vaccine, the sperm collected volume was no significant differences (P＞0.05) among the three groups, and the average sperm density was also no differences (P＞0.05) between bulls aged 24 and 32 months besides the 42 months bulls whose density of sperm was significant differences(P＜0.01) after injection. At the same time, the sperm activity in all experimental bulls was significantly lower (P＜0.01) than that before injection, and the time of the influence on 32-month-old bulls was the shortest. Otherwise, the rate of semen abandon of bulls aged 32 months was no significant differences (P＞0.05), and which was increased (P＜0.01) significantly in 24 and 42 months bulls. The number of frozen semen tubules was also no significant differences (P＞0.05) in 32 months bulls and which was obvious differences(P＜0.05) in another two groups in the later period of injection. It was concluded that injection of foot-and-mouth disease vaccine affected differently sperm quality of Fleckvieh bulls of different months, especially youth bulls.

Key words: foot-and-mouth disease vaccine; Fleckvieh; bull; sperm quality