Evaluation of formaldehyde-treated casein for wool growth and nitrogen retention

Abstract

Four sheep were given three types of casein supplements (all providing c. 16 g nitrogen per day) and the effects on wool growth rate, body weight gain, and nitrogen retention were measured. The supplements were untreated casein in the diet, untreated casein per abomasum, and formaldehyde-treated casein in the diet. Untreated casein in the diet was inferior to the other casein supplements for all parameters studied. Formaldehyde-treated casein and casein per abomasum were of similar nutritional value. The average increase in wool growth rate above the basal rate was 62% for both types of supplement; nitrogen retained was about 3 g/day, of which more than half was in wool. The treated casein was 90% digestible.