The effect of formaldehyde-treated casein on the growth of ruminant lambs

Abstract

Growth studies were made with two groups of 12 crossbred wether lambs given a diet containing 10% casein for 18 weeks from 9 weeks of age. The casein in the diet of one group was untreated but in the other was treated with formaldehyde. The group receiving the treated casein grew significantly faster and required significantly less food per unit of gain than did the lambs given untreated casein. There was no difference in the rate of wool growth. Although the digestibility of nitrogen was lower in the lambs given the treated casein, these lambs excreted less nitrogen in their urine and then nitrogen balances were higher than in the lambs given untreated casein. There appeared to be a lower proportion of fat and a higher proportion of protein in the body gain of the group receiving treated casein. The feeding of treated casein was also associated with an increase in the level of ß-ammo nitrogen and a decrease in the level of urea nitrogen in the plasma.