Natural mating is the act of reproduction between a male and a female when the latter shows signs of heat. This method of reproduction is still predominant in extensive systems for suckler cattle (70%) or suckler sheep, and in organic agriculture. In this practice, the breeder puts the male in free association with one or more females. The success rate for natural mating is 90%, compared with 72% for animal insemination (AI) for meat breeds. Natural mating can also benefit from human assistance, in the form of in-hand mating, used in particular for genetic selection and to prevent injuries.

Natural mating is a partial alternative to AI, which has become widespread in several sectors (pigs, cattle and dairy sheep). It is part of an agroecological approach since it limits the use of synthetic hormones by respecting the animals’ physiology and natural cycles. This is especially true in the dairy sheep and goat sectors, where AI is accompanied by synchronization of the ovarian cycles of females with the use of synthetic hormones.

However, in order to maintain the spread of genetic progress, particularly with regard to breed hardiness or prophylactic criteria (scrapie resistance), or to rationalize mating to limit inbreeding in native breeds with low numbers, it is necessary to carry out in-hand mating or to regularly change male breeding stock. Breeders must take into account the variability of heat occurrence in their herds. To ensure that mating takes place at the right time, they can encourage heat grouping by using alternatives to hormones, such as photoperiodic treatments, flushing or the male effect.

Nevertheless, the use of natural mating remains subject to breeding conditions and the requirements of the marketing sector.