Iodine deficiency in pigs and the solutions to the problem

Abstract

The articles provides an overview of literature dedicated to the study of iodine status in pigs and establishes an interrelation between the level of microelement in animal diet and the functional activity of thyroid gland. Close correlation between thyroid hormone levels in blood and the reproductive abilities and productiveness of pigs has been observed. Resulting thyroxin and triiodothyronine synthesis and metabolic disorders are among the most common causes of pathological states in animals, which are characterized by lower fertility, increased intrauterine fetal deaths, and birth of non-viable piglets with apparent signs of goiter. Moreover, thyroid hypofunction leads to decreased general and lipoid metabolism in pigs, young animals in particular. Feed is the source of iodine for pigs. Yet, due to intensive growing practices the primary place in pig nutrition is occupied by concentrated feed with as a rule low content of this microelement. In addition, a number of other factors affect iodine levels in organism. Iodine digestibility is particularly hindered by glucosinolates and cyanogenic glycosides, nitrates, nitrites, perchlorates, residue of some pesticides. Iodine absorption in gastrointestinal tract is slowed down by fluorine and sulfur. Pigs may receive enough iodine with additional feed containing inorganic (КІ, NaІ) and organic (iodates) compounds. For this purpose industrial farms tend to use premixtures and mineral additives containing iodine and other macro- and microelements. However, said forms of iodine-containing preparations are often unstable or even aggressive in combination with other components of additives, namely vitamins. In this connection, we are facing a relevant problem of finding new preparations that in small doses would be stable and compatible with other components of compound feed while solving the problem of microelement nutrition. In humane and veterinary medicine nanomaterials, namely metal aquachelates, are used increasingly more often. There is information as to positive impact that iodine aquacitrate has on animals which needs to be further confirmed by profound research.