Backfat and carcass composition of piglets fed milk replacers containing vegetable oil compared with sow-reared piglets.

The carcass composition of piglets fed artificial milk was compared to sow-reared piglets. The artificial milk diets contained 25%, by weight, soybean oil or mixtures of canola and high erucic acid rapeseed oil. Both the total lipid and nitrogen (apparent) digestibility of the artificial milk diets was high, even when the dietary oil contained high levels of erucic acid. Sow-reared animals were matched with the piglets receiving the artificial milk by sex and live body weight. On both a relative and an absolute basis, the piglets receiving the artificial milk diets had less carcass fat than sow-reared animals. The per cent nitrogen and ash of the carcasses of sow-reared piglets were significantly reduced compared with piglets eating milk replacer. The fatty-acid patterns of the backfat of the piglets generally resembled the patterns of the dietary lipids. Piglets eating vegetable oil diets had long-chain polyunsaturated fatty acids in their backfat, even though the oils they were consuming did not.