Micronutrients such as vitamins and minerals play an important role in reproduction. In this connection ß-carotene is probably the best known representative of this group and is important for the maintenance and function of the corpus luteum or luteal body. Particularly in spring during the mating season, it is essential to ensure that the mares get enough of this provitamin as the amounts contained in the feed are insufficient. An adequate intake of calcium during pregnancy is also vital as calcium promotes release of female sex hormones and maturation of the egg cells and can thus support fertilisation and the development of the embryo.
An adequate intake of trace elements is also extremely important for the functioning of the reproductive organs. A manganese deficiency, for example, can lead to changes in the uterine lining. The contractility is then considerably impaired so that the uterus no longer responds to oestrogens and in the case of a severe deficiency can become entirely atonic.