Seasonal study of serumic zinc levels in cows suspected of deficiency and its relationship with diet in industrial dairy farms of Urmia

Considering the very important role of zinc in structural and physiological functions of livestock body and the paucity of research in the regions, the objective of this study was to investigate zinc deficiency in cows suspected of deficiency in industrial dairy farms of Urmia and its relationship with diet of the animals. In this study, blood samples were taken from cows suspected of deficiency including animals that had anorexia, decrease in production and most importantly infertility problems. Samples were also taken from the animals diets. Sampling was conducted on a seasonal basis and 25 serum samples were collected in each season. Measurement was performed using atomic absorption method and serumic levels were calculated in micromoles. The results of this study indicated that in the animals suspected of zinc deficiency, there was no significant difference between different seasons but zinc levels were below normal in winter, spring and autumn. It is probable that dietary zinc deficiency especially low zinc levels in concentrate diets in the main cause of low zinc values in this study.