Influence of different fat supplements on digestibility and ruminal digestion in cows

— In two trials each using 3 cows fitted with, rument cannulas, the effects of different lipid supplements on digestibility and ruminal digestion were analyzed. In trial 1, a control diet based on maize silage (Ci ) was compared to the same diet with a supplement of crude (untreated) bone fat (UF) and with a crystalline animal fat (CF). In trial 2, a control diet (C2) similar to diet C1 was com- pared to the same diet with a supplement of protein-coated (encapsulated) fat (EF). Fatty acid con- tent in dry matter was 2.5% for control diets, 8.1 to 9.1 % for supplemented diets. Apparent digestibility of nutrients, pH and volatile fatty acids in rumen juice, in sacco degradability of dry matter and cell walls were determined.