Effect of Bioactive Fatty Acids on Growth Performance of Milk-Fed Holstein Dairy Calves Under Cold Stress

In order to evaluate the effects of Omega-3 and Omega-6 fatty acids on the growth performance of milk-fed Holstein calves in the cold season, forty newborn calves (41.8 kg of body weight, average age=4 days) in 65 days period were allocated to one of four diets and ten calves per group, in balanced randomized complete design as the repeated measurements over time. The experimental treatments as follows: (1) starter feed supplemented with no fat source (CON), (2) starter feed supplemented with 3% Ca-salts of soybean oil rich in n-6 FA, (3) starter feed supplemented with 3% Ca-salts of fish oil rich in n-3 FA, and (4) starter feed supplemented with an equal mixture of Ca-salts of soybean and fish oil (1.5% each, DM basis). Calf starter intake in OMEGA-3 was higher than others (p<0.01), whereas the control group significantly reduced starter intake. Average Daily Gain was higher in OMEGA-3 in the entire period (3-60 d) (p=0.0309). Feeding supplemental 3% fish oil improved feed efficiency compared to control and Ca-salts of soybean oil treatments (p<0.01). Calves in the OMEGA-3 group had higher body weight at weaning (p=0.0100). The Omega-3 group had better fecal scores and fewer days with diarrhea and control group had higher. Based on the results of this experiment, simultaneous consumption of Omega-3 fatty acids under cold stress can play an important role in improving calf health and guarantee optimal growth.