Studies on the Experimental Production and Prevention of Bloat in Cattle. III. The Effect of Vegetable Oil and Animal Fat on Acute Legume Bloat

Abstract

Summary The influence of animal and vegetable fats on ruminal motility, eructation, and bloat has been investigated in dairy cattle receiving freshly harvested alfalfa tops under laboratory and feed-lot conditions. Five eructation and rumen motility trials were conducted on a nonlactating cow having a transected trachea and a ruminal fistula. It was found that the administration of vegetable oil before alfalfa feeding prevented the development of bloat symptoms. Oil administered during the development of bloat increased the rate of eructation and the volume of gas expelled and reduced intrarumen pressure within 15 min. In the feed-lot trials, eight intact cows, selected for bloat susceptibility, were fed freshly chopped alfalfa with and without the addition of fat. Three types of feeding regimes were followed using reversal type experiments: (1) alfalfa alone; (2) alfalfa containing vegetable oil added at the rate of 1 ml. per pound, and (3) a prefeeding of a concentrate mixture containing various levels of animal tallows followed by alfalfa. The incidence and severity of bloat were estimated with a tympanometer. Fat intakes in excess of 0.06 lb. per head per feeding period prevented bloat for the period immediately following their administration. Bloat prevention was accompanied by a marked and statistically significant increase in alfalfa consumption. These effects did not carry over to the subsequent feeding period, even at intakes of 0.5 lb. of tallow per head. It is concluded that foaming of the rumen ingesta is an important factor in the etiology of acute legume bloat. Rumen motility studies indicate that there is a sufficient number of secondary (eructation) contractions occurring during the development of bloat to relieve the pressure, if the cardia can be cleared of foam. Animal and vegetable fats prevent acute legume bloat by exerting such an effect.