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Effect of an Injection of a Fat Soluble Vitamin Mix (E, A, and D) to Newborn Beef Calves on Markers of Cell Oxidative Damage and Calf Performance
Early calf death is one of the major contributors to economic loss, and muscle lesions not related to white muscle disease may contribute to reduced vigor of calves suffering from weak calf syndrome. The objective of the current study was to determine the effects of vitamin E, A and D injection on calves exposed to cold temperature. Thirty-two newborn calves from spring calving multiparous Charolais cows (age 3-10 years) were blocked within gender by date of birth and assigned to treatment in a 2x2 factorial design. At birth, calves were administered an injection of 4 ml of saline (SAL), or 4 ml VITAL E-A+D (EAD: 300 IU/mL vitamin E as d-a-tocopherol, 100,000 IU/mL vitamin A as retinyl-palmitate, and 10,000 IU/mL vitamin D as cholecalciferol). At 5 h of age, the calves were placed in a chamber at 0 or 25°C for 90 minutes and rectal temperature was recorded every 10 minutes. At 24 h of age, an injection of Bo-Se (2 mg of selenium as sodium selenite and 136 IU of Vitamin E as d-a-tocopheryl acetate) was administered to all calves. Plasma samples were collected at birth, 5 h, 6.5 h, 24 h, 48 h, and 45 d. Plasma creatine kinase and 8-isoprostane concentrations at 24 h were not affected (P > 0.48) by injection or environmental treatment, showing no effect of treatment on markers of cell damage. Regardless of temperature treatment, calves receiving the EAD had greater rectal temperatures (P = 0.04) than those calves receiving SAL (38.85 vs. 38.75 ± 0.03 °C, respectively) at birth. Calves subjected to cold temperature had greater (P = 0.05) rectal temperatures than the calves subjected to thermo-neutral conditions. Calves receiving EAD had lesser (P = 0.02) ADG during the first 5.5 weeks of life than those receiving SAL (0.93 vs. 1.14 ± 0.06 kg/d). However, 205 d adjusted weaning weights were not different (P= 0.58) between injection treatments (254 vs. 260 ± 8.2 kg for EAD and SAL, respectively). Calves receiving EAD had greater rectal temperatures and lower average daily gains than calves receiving SAL. There was no detectable difference in markers of cell damage due to treatments. Calves receiving EAD may have had increased metabolic rates which could have contributed to the increase in rectal temperature and decreased ADG. Injection of EAD at birth may be beneficial to calf health in terms of body heat production.
Keywords: calf, injectable vitamin