Experiments with a feed fat supplement on the basis of free saturated fatty acids in feeding of lactating dairy cows

In a longterm experiment with 60 high producing dairy cows of black and white breed with high portions of HF divided In two equal groups by pair-technique the influence of a feed-fat-supplement to the concentrate including the feed additive CRINA HC 900 on milk- and fertility-performance was investigated under definited conditions. The feed-fat was a product of C 16:0 and C 18:0 fatty acids, the feed additive belonged to the group of essential oils. The results of the experiment demonstrate a significant effect of the combined treat ment on FCM-yield by 11,5%, on milk-fat performance by 14% and on milk-protein production by 12,3%. Furthermore the fat content of milk was increased by 5,8% and the protein content of milk was increased by 3,9%. The cell count of the milk was decreased during the experimental period by 36%. The fertility of the cows was improved by artificial insemination Index, intercalving time and veterinary treatment of sterility. The Influence of the feed fat supplement on protein content of the milk is inconsistent to many results of the international literature with calcium-soaps. The mode of action of the feed supplements was discussed under special consideration of physiological effects. The influence of the feed fat on FCM yield can be related to a higher energy supply of the cows by the daily ration, the influence on the protein content or milk are probably the results of an intramammarian stimulation of the protein metabolism between blood and alveolar cells by the essential oils. The depression effects on cell count may be the result of a metabolic stimulation by the combination of feed fat as energy source and of essential oils as enzyme activator.