The Differences in Sperm Concentration and Semen Volume in Different Segments in one Boar Ejaculation

There is one to several short pauses during the boar's whole ejaculation.The semen of the whole ejaculation was divided into three segments: concentrated semen(segment 1),the semen of the first ejaculate with the exception of the concentrated semen(segment 2),the rest part(segment 3).The differences in sperm concentration and semen volume in these three different segments were studied.The results showed that the volume of the concentrated semen was significantly lower than that of the other two segments(P0.01),whereas the sperm concentration and sperm number were significantly higher than those of the other two segments(P0.01).The concentrated semen occupied only about 17% of the whole semen volume whereas about 71% of the total sperm number.The first ejaculate accounted for about 70% of semen volume and 95% of sperms of the whole ejaculation.