Influence of hormonal secretion and fertility in merino mutton sheep by exogenous pheromone application during the breeding season.

The effect of a ram-pheromome extracted from the wool of insemination rams with excellent libido sexualis of the merino mutton sheep breed was examined with respect to the hormonal secretion and fertility of adult ewes during the breeding season. A control group (untreated animals) was at disposal for every experiment. There were significant differences between the ewes treated with pheromone and the controls in the course of the preovulatory LH wave and the oestradiol concentration of the oestrus sheep at the beginning of the breeding season. The ovulation in ewes after prostaglandin application was stimulated by pheromone applications. The regime practised in the experiment on pherome application had a positive influence on the conception rate of the inseminated ewes and resulted in a significant increase of the lambing results (lambs/birth).