Further studies on the use of nicotine to promote leanness in pigs.

Four experiments using weight gain, feed efficiency and carcass analysis criteria were conducted with 148 pigs to determine the effects of feeding nicotine sulfate at various levels on protein and fat deposition. A level of 5 p.p.m. of nicotine sulfate in the ration fed to pigs from weaning until market weight significantly decreased (P<.05) the depth of loin fat in two of three experiments in which it was tested and slightly increased the carcass protein: fat ratio in all experiments. A level of 20 p.p.m. was as effective as 5 p.p.m. but higher levels of 40 and 80 p.p.m. had no effect on carcass quality. The fat content of the livers of pigs fed 5 p.p.m. of nicotine sulfate was found to be 8 to 10 per cent higher than that of controls in the two experiments in which it was measured. Higher levels of nicotine had little or no effect on liver lipids. Plasma cholesterol levels of pigs were not increased by the feeding of nicotine sulfate at levels of 5, 20 and 80 p.p.m.