Effects of Extra Nutritional Vitamin D3 Levels on Physiological Response of Broiler Chicks Exposed to Repeated Lactic Acidosis

A number of 144 male Ross-308 broiler chicks (18-day old) were used to investigate the effects of extra nutritional vitamin D3 levels on the physiological response of broiler chicks exposed to lactic acidosis stress. Effects of the six experimental treatment consisting subcutaneous (SC) injection of 0 (control- and control+), 20000, 30000, 40000, and 50000 IU of vitamin D3 were examined in four replicates of six birds in a complete randomized block design during days 21 to 29 of age. Lactic acidosis is a form of metabolic acidosis that begins when a bird overproduces or underutilizes lactic acid, and their body is not able to adjust to these changes. Liver fat percentage decreased in the birds receiving 50000 IU of vitamin D3 compared with the control birds (P < 0.036). Administration of 30000 IU vitamin D3 enhanced serum concentration of creatinine by 18.52 percent compared with the control+ birds (P < 0.0001). Injection of 50000 and 40000 IU vitamin D3 decreased serum concentration of lactate dehydrogenase by 24.99 and 19.81 percent, respectively, compared with the control+ birds (P < 0.0003). The mean serum activity of alanine aminotransferase in the birds receiving 20000 IU vitamin D3 was greater by 28.57, 18.84, and 17.32 percent, compared with the control+ birds and those received 40000 and 50000 IU, respectively (P < 0.008). It was concluded that administration of extra nutritional vitamin D3 up to 50000 IU per bird resulted in broad but inconsistent changes in the blood biochemical and enzymatic parameters in birds exposed to lactic acid. No firm evidence was found to suggest a protective effect vitamin D3 on the incidence of sudden death syndrome in broilers during lactic acidosis.