The effects of intra-ruminal infusions of volatile fatty acids on food intake of sheep

Abstract

The effects of intra-ruminal infusions of varying dose rates of acetic and propionic acids on the food intake of sheep on high and low planes of nutrition were studied. As the dose rate of acetic acid was increased intake decreased and was significantly different from the control intake at a dose rate of 200 Cal. on both planes of nutrition. However, the depression of food intake was more pronounced on the low than the high plane of nutrition. Infusions of 200 Cal. of propionic acid caused a small increase of food intake on both planes of nutrition, while 300 Cal. caused a significant depression on the low plane of nutrition. Propionic acid infusions had a cumulative effect on the high plane of nutrition where both treatment and control intakes decreased as the dose rate of acid was increased. Butyric acid was not studied in detail but infusions of 400 Cal. were observed to depress food intake. The results are discussed in relation to the possible role of acetate as a “chemostatic” regulator of satiety in ruminants.