Untreated and formaldehyde treated skimmilk powder as a protein supplement for dairy cows

Abstract

Twenty four high producing dairy cows were used in an experiment in which the value of fat free spray-dried milk powder, untreated or formaldehyde treated (0.4 g formaldehyde/100 g crude protein), was studied as a protein supplement in a protein deficient diet. The groups were: 1) Protein shortage group, 1) Untreated milk powder group and 3) Formaldehyde treated milk powder group. Rations were made for all groups from hay, grass silage, barley, oats and mineral and vitamin mixtures according to nutrient requirements excepting that of protein. In the rations of the protein shortage group 25 % of the DCP required for milk production was omitted. In the other groups this deficiency was filled with untreated or formaldehyde treated milk protein. The experiment lasted 15 weeks. The feed consumption and utilization, milk production and composition, and blood contents were determined. In eliminating the protein deficiency with fat free milk powder positive results were found in milk yields, the protein content of the milk and in the live weight of the cows. The differences in the utilization of untreated and formaldehyde treated milk powder were not significant. Only small amounts of formaldehyde (0.11 mg/kg milk), were found in the milk of the cows receiving formaldehyde treated protein. The values of the blood analyses remained within the normal ranges on all diets.