In this experiment, we examined the effects of low-digestible crude protein (DCP) feed supplemented with amino acids on nitrogen excretion from feces and urine of growing-fattening pigs during the pre-fattening period (30-70kg) and fattening period (70-110kg) and on the density of ammonium gas from feces and urine in pigs at a body weight 110kg.
Eight hogs (crossbred) were used in this study and were divided into two groups having the same mean body weight. Feed was prepared as follows; standard feed containing DCP of 12.5% and 10.5% for the pre-fattening and fattening periods, respectively, and low-DCP feed containing DCP of 8.5% and 6.5% (a 4% reduction of DCP from the Japanese Feeding Standard for Swine) supplemented with amino acids (lysine, methionine, tryptophan, threonine and isoleucine). The total digestible nutrient ratio was nearly the same. Feed intake, water intake, feces amount, urine volume, nitrogen and mineral contents during the test period and ammonium gas generation density from the feces and urine of 110kg pigs were determined in this study.
There was no significant difference in feed intake during the test period, but water intake was less in the low-DCP feed with amino acids group. The amount of feces showed no significant difference, but the urine volume in the low-DCP feed with amino acids group was less than that of the standard feed group as was the decrease in water intake. Although feces from both groups had similar nitrogen values, for urine nitrogen content, nitrogen intake decreased by two-thirds in the low-DCP feed with amino acids group. Mineral content excretion from feces and urine during the fattening period tended to increase in comparison with that during the pre-fattening period. The density of ammonium gas generation from feces and urine was reduced by the intake of low-DCP feed with amino acids. The peak of ammonium gas generation in the low-DCP feed with amino acids group occurred later than that in the standard feed group.
These results suggest that low-DCP feed supplemented with amino acids is a valuable method for increasing the nitrogen utilization ratio and reducing nitrogen excretion, however changes in the mineral content of urine and feces must be further examined.

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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 70kg of live weight and were slaughtered at 105kg. Growth rate and performance of meat production were recorded for each pig and loins (M. longis-simus 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 II (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 1 were between 46.48 to 53.14mg/100g 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.

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