Proteinkvalitet och biogena aminer i ensilage – effekt på mjölkkors hälsa & foderintag

Abstract: The aim of this paper was to explain protein degradation in silage and protein quality and biogenic amines in silage and their effects on the health of the dairy cows. After harvest-ing, the plant proteases degrade the proteins in the plant. The protein degrades to different fractions with different digestibilites in the rumen. Fraction A contains non- protein nitro-gen which is peptides, free amino acids and amines. True protein is in the fraction B and is further divided into three subfractions depending on their solubility. Fraction C is insoluble and bound to the lignin-cellulose complex. Biogenic amines are found naturally in forages but can also be formed by microorganisms. Proteolytic clostridia and enterobacteria can decarboxylate free amino acids to biogenic amines. By using additives in silage making the pH is decreased rapidly and the protein degradation is decreased. In silage with less than 50 % true protein of crude protein different symptoms have been observed when itis feed to dairy cows. Symptoms are, for example, high somatic cell count in milk, displaced abo-masum and fertility problems. Studies have shown that biogenic amines are accountable for decreased feed intake, ketonemi and impaired immune function in ruminants. Decreased feed intake can impair the negative energy balance after parturition, which can impair the immune defense and health problems. The conclusion of the paper was that it is worth reducing the protein degradation in silage, because the studies have shown that it influences the health of dairy cows. More studies are needed to understand the silage pro-tein quality and the effect of biogenic amines on feed intake and health.