Some Effects of Feeding Animal Fat and N,N'-Diphenyl-P-Phenylenediamine to Swine

Twenty-four Palouse pigs were divided into four groups of 6 pigs and individually self-fed the experimental rations. The variables were a 10% level of added inedible animal fat and a 0.1% level of N,N'diphenyl-para-phenylenediamine (DPPD). The pigs were treated as follows: Group I received no added dietary fat during the entire experimental period. Group II was fed a ration which contained 10% added fat until 120 1b. body weight and no added fat thereafter. Group III received no added fat to 120 lb. and then a 10% added fat ration until slaughter (195 lb.). Group IV was fed a ration containing a 10% level of added fat throughout the entire experimental period. DPPD was fed at a 0.1% level to half the animals in each group. Added animal fat significantly increased the rate of gain when fed to pigs to a weight of 120 lb. (P<.01) and when fed between weights of 120 to 195 lb. (P<.05). The number of days required to reach a weight of 120 lb. was significantly less for the groups receiving fat in the ration (P<.05). Feed efficiency was also significantly improved by feeding added fat until pigs reached 120 lb. body weight (P<.05). Added fat did not significantly improve feed efficiency when fed to hogs only between 120 and 195 lbs. body weight. The carcass measurements taken were not affected by feeding a 10% added level of animal fat in the rations. Feeding DPPD in the swine rations did not significantly influence the rate of gain, number of days required until slaughter, or feed efficiency. The dietary antioxidant did, however, significantly (P<.01) decrease the peroxide value of fat samples taken at slaughter and stored for 21 days at 36° F.