PERFORMANCE AND HISTOLOGICAL CHANGES IN TISSUES OF PIGS FED DIETS CONTAINING HIGH OR LOW ERUCIC ACID RAPESEED OILS OR SOYBEAN OIL

Three experiments were conducted to compare high (20.6%) or low (4.0%) erucic acid rapeseed oils with soybean oil when the oils were fed at a level of 15% of the diet for pigs from 25 to 90 kg liveweight. The low erucic acid rapeseed oil originated from Brassica campestris cv. Span. A fourth diet containing no supplemental oil served as a control. In one experiment, 48 crossbred pigs were fed ad libitum in groups of three pigs replicated four times. In a second experiment, 48 pigs were individually fed at a level of 80% of the daily caloric intake of the pigs in the first experiment. In a third experiment, 16 pigs in four groups were allowed continuous free-choice access to the four diets. Serial slaughter and digestibility data were obtained. The incorporation of high or low erucic acid rapeseed oil in the diets did not reduce pig performance when such diets were fed either ad libitum or at a restricted level. When given a choice of feed, pigs selected less of the high erucic acid rapeseed oil diet. When not given a choice of feed, pigs consumed as much of a high erucic acid rapeseed oil diet as they did of the other diets. Digestibility coefficients for energy, nitrogen and lipids were not significantly different for any of the three oil-containing diets. Histological examination of the heart, liver and spleen revealed no marked differences due to feeding any of the oil-based diets.