We established the effects of wet/dry feeding on the eating speed of finishing pigs through two experiments: a feeding test (Experiment 1) and a basic test on five types of feed with different mixing ratios of feed and water (Experiment 2).
In Experiment 1, wet/dry feeding for pigs in which water and feed were supplied simultaneously was compared with conventional ad libitum feeding in which air-dry feed and water were supplied separately (control section). The ledge type wet/dry feeder and nose operated flap type wet/dry feeder tended to increase daily feed intake in the latter finishing period of pigs than the ad libitum feeder. The eating speed of pigs in wet/dry feeding was significantly higher (P<0.01) than that in control section. In Experiment 2, the composition of feed and water (weight ratio) was varied in mixing ratios: Section A (air-dry feed 1 to water 0), Section B (1:0.5), Section C (1:1), Section D (1:2), and Section E (1:3). Feed intake of pigs for first ten minutes after starting to eat and eating speed (g/min) significantly increased (P<0.01) in the sections of feed and water mixture compared with the section of air-dry feed alone (Section A). The order from greatest to least was as follows: C>D>E>B>A. Significant regressions of the second degree were established between the water content in feed and the eating speed at 60kg, 80kg and 105kg of the pigs' body weights. The eating speed increased most when the water content of feed was 62-69%. No significant differences were observed among sections for the initial eating time, the number of breaks in eating, and average duration of eating.
From the above, it was estimated that in wet/dry feeding, the reduced eating time was caused by the increased eating speed, and that the mixing ratios to maximize the eating speed were air-dry feed 1 to water 1.3-1.8.

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The amino acids concentration of peptide and whole defatted milk hydrolysate in sow colostrum was determined from farrowing to 1 week postpartum in this study.
Proline was the most abundant amino acid at all times in peptide hydrolysate, which occupied 27% of total amino acids, followed by glutamate+glutamine and glycine. The contents of these three amino acids composed 68% to 75% of total amino acids in peptide hydrolysate. The concentration of essential amino acids was less than that of nonessential amino acids in peptide hydrolysate. Arginine content was predominant among essential amino acids.
All amino acids concentration, except for methionine, decreased drastically from farrowing to 24 hours postpartum in whole defatted milk hydrolysate (p<0.05). Glutamate+glutamine was the most abundant amino acid in whole defatted milk hydrolysate, followed by proline, leucine and aspartate+asparagine in order of concentration from greater to less at all times. Methionine and cystine showed the least amount in both peptide and whole defatted milk hydrolysate.
The concentration ratio of total amino acids of peptide hydrolysate to that of whole defatted milk hydrolysate in colostrum increased linearly from 3.6% at parturition to 13.6% at 1 week postpartum because amino acids concentration of peptide hydrolysate remained relatively constant through the experimental period while that of whole defatted milk hydrolysate decreased remarkably from farrowing to 24 hours postpartum.
These results suggested that the amount of peptide in sow colostrum and mature milk can affect digestion and body protein synthesis of piglets.

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Sixty-four pigs were used to determine the effect of feeding reduced crude protein (CP), amino acid (AA)-supplemented diets on nitrogen excretion during growing (30 to 70kg BW) and finishing (70 to 105kg BW) period. Pigs were fed either diets containing standard CP, or diets reduced in CP by 4% units with or without lysine and threonine supplementation. The amounts of nitrogen retention were estimated by the equations shown in Japanese Feeding Standard for Swine (1993), and fecal and urinary nitrogen excretions were calculated on the intake, absorption and retention of nitrogen.
During the growing period, daily gain and feed conversion were similar between pigs fed the AA-supplemented low-CP diets and those fed the standard-CP diets, but during the finishing period AA supplementation of the low-CP diet failed to improve growth performance to the levels attained by pigs fed the standard-CP diets. Reduction of dietary CP without AA supplementation dramatically reduced pig growth performance in the both periods.
Feeding reduced dietary CP, regardless of AA supplementation, resulted in reduced urinary nitrogen excretion compared with feeding the standard-CP diets. The average amount of urinary nitrogen excretion for pigs fed the AA-supplemented low-CP diets was 63% and 68% of that for pigs fed the standard-CP diets in growing period and finishinig period, respectively. Fecal nitrogen excretion showed to be similar in pattern to that of urinary one except that the differences were less pronounced.

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