Characteristics of lipids in pork fed diets containing food by-products

Concentrations supplemented with sake rice crumbs, dried tea leaf meal, wakame seaweed meal together with bread crumbs were fed to barrows (Landrace * Large white * Duloc) and comparisons were made for contents of total lipid, cholesterol and fatty acid composition in the loin. The pigs started to receive the diets at 70 kg of live weight and were slaughtered at 105kg. Growth rate and performance of meat production were recorded for each pig and loins (M. longissimus thoracis) were separated from the carcasses between the 12th and 13th ribs one day after the slaughter. Experimental treatments were as follows ; supplementing with sake rice crumbs (experiment 1), feeding nutrition enhanced diet, 10 and 30% of that replaced with sake rice crumbs, respectively ; supplementing with tea leaf meal I (experiment 2), feeding concentrate as a control and 0.8% of that replaced with tea leaf crumbs ; supplementing with tea leaf meal 2 (experiment 3), feeding concentrate as a control, 1 and 3% of that replaced with tea leaf meal, respectively ; supplementing with wakame seaweed meal and bread crumbs (experiment 4), feeding concentrate as a control, 0.3% of that replaced with wakame seaweed meal, 5% of that replaced with bread crumbs and replaced with both wakame seaweed meal and bread crumbs. Total lipid contents of the loins ranged from 2.16 to 2.50% in experiment 1 and they were not significantly different in experiment 2 and experiment 3 compared with the controls in each experiment. In Experiment 4, supplementing with bread crumbs resulted in 1.81%-3.79%, but statistical significance was not obtained due to rather large variations within the treatments. Cholesterol levels in the loins in experiment I were between 46.48 to 53.14 mg/100 g and no obvious effects of the treatments were noted. Supplementing with tea leaf meal (experiments 2 and 3) tended to have higher levels than those of the controls. In experiment 4, slightly lower levels of cholesterol were recorded for supplementing with wakame seaweed meal without any statistical significance. Supplementing with sake rice crumbs did not affect meat production performances and characteristics of lipids. Although delayed growth in pig supplemented with tea leaf meal has been reported, there were, in this study, only a little effects of tea leaf meal on fatty acid composition in this study. Supplementing with wakame seaweed and bread crumbs somewhat altered fatty acid composition. Results in this study indicate that these food by-products except the wakame seaweed can be used as supplements to pig feed.