SELECTION OF BULLS FOR ARTIFICIAL-INSEMINATION ACCORDING TO SEXUAL PERFORMANCE

The French Artificial Insemination Cooperatives have been involved for 20 years approximately, in a special breeding soundness programme. The aim of this review is to report on the procedure used in such a programme and on the beneficial effects that have resulted, in the semen production in the Artificial insemination Centers on the one hand and on the next generations of bulls on the other hand. This programme is conducted on young post-pubertal bulls, aged 12-15 months approximately. It relies on the evaluation of the libido, the testis morphology and on the semen production and its ability to sustain deep freezing. Ten ejaculates are sufficient to be accurately discriminative in between individuals (one double ejaculation weekly usually). Following these tests, bulls are classified and those that rank unsatisfactory are discarded. This concerns 20 % of the bulls on average. Such a selection results in a significant improvement of the semen production in the Artificial Insemination Centers (very low percentage of semen discarded) and also contributes to improve the breeding soundness performances of the male offsprings. Combined with its indirect effect on the female fertility, such a selection of the bulls that enter the artificial Insemination centers results in a major contribution to enhance the overall fertility rate of the national cattle population bred by the means of Artificial Insemination.