Assessment of fertilizing potential in crossbred breeding bulls by some current diagnostic approach in vitro

Semen samples collected from best selected breeding bulls of 2 different tr iple crossbreds were subjected to be tested by BCMPT, HOST and ZHPT after b eing evaluated routinely and the same samples were confirmed in field artif icial insemination trials. Majority of the tests like individual motility, normal percentage, cold shock resistance and MBRT showed a significant posi tive correlation with fertility. In BCMPT, no statistical difference was ob served with diluted semen, but observed significantly (P<0.05) with the nea t semen which also exhibited a nonsignificant negative correlation with fie ld Al trials. In HOST, the "g" type (total tail swollen) per cent of sperms revealed a significant difference (P<0.01) among the 4 bulls acid showed a highly significant positive correlation with field fertility trials. In ZH PT, a significant (P<0.05) variation was observed among the bulls for FP an d FI, but these 2 values indicated a nonsignificant negative correlation wi th field fertility trials. BCMPT, HOST and ZHPT can effectively be used in combination with conventional techniques in vitro to select a sire in cross bred bovine.