The Effect of Different Sources of Selenium on Performance, Health, Growth Factor and Some Blood Parameters of Holestine Dairy Calves

The  low-consumption  elements such as selenium can be included in the diet from a variety of sources. The purpose of this study was to investigate the effects of incorporation of inorganic, organic and nano selenium in the diets of dairy calves on their performance, health, growth factor and some of their blood parameters. Forty-eight newborn Holstein calves were used in a completely randomized design over a 60-day period with four treatments (6 females and 6 males per treatment) as follows: 1) control diet without selenium, 2) mineralized selenium supplemented diet, 3) organic selenium supplemented diet, and 4) nano selenium supplemented diet. Except for control (1) other treatments had the same concentration of selenium (0.3 mg / kg diet). Body weight changes, growth parameters, fecal consistency, health scores, biochemical metabolites, liver enzymes activity, glutathione peroxidase, total antioxidant capacity, non-esterified fatty acid values, beta-hydroxybutyric acid and malondialdehyde were measured. The results showed that selenium sources were ineffective on feeding and DM intake before weaning. Supplementation with selenium did not affect the live weight of the calves. Selenium sources had do not affect on blood parameters, while total blood antioxidant capacity was higher in calves containing organic selenium compared to other treatments (0.506 mmol / L). Body length, chest circumference and body capacity were affected by different sources of selenium. Nano-selenium supplementation increased the height of calves in comparison with other treatments. The present results showed that the optimum source of selenium was organic selenium for dairy calves.