Manda Srinivas

Semen Characteristics of Normal and Low Grade Ejaculates in Ongole(Bos indicus) Bulls

The normal and low-grade ejaculates collected from the eight bulls under study were evaluated of various semen parameters. The overall means of HOS-G sperm was recorded as 56.50 ± 0.50 and 30.35 ± 0.66 percent for HOS positive and acrosome positive (HPAP), 17.30 ± 0.54 and 19.48 ± 0.66 percent for HOS positive and acrosome negative (HPAN), 18.73 ± 0.54 and 30.11 ± 0.89 percent for HOS negative and acrosome positive (HNAP) and 7.64 ± 0.47 and 19.63 ± 0.94 percent for HOS negative and acrosome negative (HNAN) in fresh semen of normal and low grade ejaculates, respectively. The overall mean sperm penetration distance was recorded as 19.75 ± 0.19 and 14.40 ± 0.19 mm/20 min in normal and low grade ejaculates (Table 1) with a highly significant difference between them (P<0.01). The sperm penetration distance (mm/20 min) differed only amongst bulls of low grade ejaculates and not among those of normal ejaculates. It was concluded from the present study that routine semen evaluation tests which are mainly subjective in nature suffered human bias and have limited ability to predict the fertilizing capacity of the sperm, hence still more sensitive tests like functional assessment of plasma membrane and acrosome membrane (HOS-G Test) and sperm penetration distance in synthetic medium are essential to predict optimum fertility.