Effect Of Vegetable Oils Research Articles

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

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.

THE PREVENTION OF NUTRITIONAL ENCEPHALOMALACIA IN CHICKS BY VEGETABLE OILS AND THEIR FRACTIONS

One of the disorders occurring in young chicks upon synthetic diets is characterized by severe pathological changes in the central nervous system (l-3). This disease, for which we have suggested the term nutritional encephalomalacia, has no correlation with body weight, sex, or breed of chick (4) and develops only during the period of active brain growth (5). The disease is not infectious nor transmissible by inoculation. Since the disorder was observed but rarely upon diets of natural foods, experimentation on the possible dietary factors was begun by incorporating in the synthetic diet various natural foods, such as grains, grain products, green foodstuffs, animal tissues, or animal products. The ineffectiveness of these supplements led to further experiments in which the content of mineral, fat, carbohydrate, and vitamin of the synthetic diet was varied. A high proportion of lard in the diet seemed to favor the development of the disease. When the lard was replaced by vegetable oils, these were found to provide complete protection (6). We wish to report experiments demonstrating this protective effect of vegetable oils. It will be shown also that the preventive factor is contained in the non-saponifiable fracti0n.l Care and Examination of Animal-White Leghorn chicks of accredited stock were obtained from Hall Brothers, Wallingford,