Effect of Omega-3 and Omega-6 Fatty Acid on Growth Performance, Blood Metabolites and Health indicators of Weaning Holstein Calves

In Suckling calves, due to the low development of rumen, the digestibility of food may decrease, so the energy of the diet can be increased by adding fat sources. The present experiment was conducted to investigate the effect of omega-3 and omega-6 fatty acids on feed intake and growth parameters of Holstein calves.

A total of 40 newborn calves (average age 3 days), for 60 days, in the form of a repeated design to 4 treatments including: (1) no supplemented fat source (control; CON), (2) 3% calcium-salts of soybean oil (Ca-SBO), (3) 3% calcium-salts of flaxseed oil (Ca-CO), and (4) 3% mixture of Ca-SBO and Ca-CO (1.5% each, DM basis; MIX). The study continued 66 days and the calves were gradually weaned during 61-65 days of age.

The starter intake during the period of 31 to 60 days for the control treatment was higher than the other treatments (p=0.05), but no differences were observed among the treatments in the entire experimental period. The daily weight gain in the periods of 31 to 60 days and the whole period for the treatment containing soybean oil supplement was better than the control treatment (p<0.05). Regarding body weight, soybean oil treatment had the highest weight at the end of the experiment. In terms of feed efficiency, mixed oil treatment had better performance than the control and flaxseed oil treatment, and it was not significantly difference with soybean oil treatment (p<0.05). Regarding blood metabolites, a significant differences were observed between experimental treatments in terms of glucose, total protein, cholesterol and other metabolites. Also, the liver enzyme concentration of aspartate aminotransferase for the treatment containing soybean oil on the 60th day of the experiment was the lowest compared to other treatments (p<0.01).

In general, the results showed that the use of soybean oil as a source of omega-3 fatty acids has more positive effects on the growth performance of Holstein suckling calves than flaxseed oil.