Fish Oil Supplementation on Growth and Health of Pre-Weaning Dairy Calves
The objective of this study was to study the effect of fish oill (energy source) for preweaning calves. Preweaning calves were more sensitive to environment and stress to sickness. Thirty six male dairy calves fed with 0% (group 1), 2.5% (group 2), and 5% (group 3) of fish oil in milk replacer. All calves were assigned with randomized complete block design. The calves were placed into individual pen after birth randomly. Calves were fed with colostrum after birth until 3 d of age. Calves were fed calf starter and milk replacer from d 4 to d 42 of age. All calves fed with calf starter and water in different bucket set in the front of pen. Calves were fed 5 kg/h/d milk replacer, 2 times a day. All calves were weaned on d 42. Body weights were measured after birth and d 1, d 21 and d 42. Feed and milk replacer intake and fecal scores were measured daily after feeding in the morning. Blood samples were collected on d 1, d 21 and d 42 after morning feeding for 2 hrs for chemical analysis. Growth, health and neutrophils and lymphocytes (stress indices) were evaluated for 42 days. Average daily gain (131.6, 141.5, and 118.4 g/d for group 1, 2, and 3, respectively), feed intake, fecal score, and body cleanliness score of calves did not differ (P > 0.05) among treatments but feed intake was affected by week (P < 0.0001). Calf health was also affected by week (P < 0.001). Immunoglobulin G was higher on d 1 (40.1 mg/ml, P < 0.05). The ratio of neutrophils and lymphocytes (1.13, 0.46, and 0.26 for d 1, d 21, and d 42, respectively), glucose concentration (163.7, 115.1, and 104.1 mg/dl for d 1, d 21, and d 42, respectively) decreased when calf was older (P < 0.001). Growth and health performance of calves fed with three levels of fish oil did not differ (P > 0.05). At 3 weeks of ages, immunoglobulin G of calves was increased as calf fed 2.5% fish oil supplemented in milk replacer.
Keywords: Fish oil, dairy calf, health