A study was made on the genetic relationships of body measurements at registration to a couple of reproductive traits in Japanese Black females. Genetic parameters were calculated using a REML procedure under multiple-trait animal model. The field records on six body measurements and three reproductive traits of 14, 881 Japanese Black females were analyzed. Body measurements included withers height, chest girth, chest depth, rump length, thurl width and body weight, and reproductive traits included age at first calving, first calving interval and gestation length. Heritability estimates for body measurements were moderate (0.33 for chestgirth, 0.35 for chest depth, 0.39 for rump length, 0.34 for thurl width and 0.39 for body weight) to high (0.45 for withers height), while those for reproductive traits were low (0.04 for age at first calving to 0.17 for gestation length). High and positive genetic correlation coefficients of 0.50 to 0.87 were obtained among body measurements. Most body measurements had negative genetic relationships with reproductive traits. Thurl width had a closest genetic correlation (-0.38) with age at first calving, while rump length had a closest correlation (-0.34) with calving interval. Withers height, which was thought to be an important indicator for growth performance and first insemination, had only low and negative genetic correlation with age at first calving (-0.19), though it had a negative and closest correlation with gestation length (-0.48). Body weight had no close genetic correlation with any reproductive traits (-0.12 to -0.16). Concerning reproductive traits, it may be said that all of the body measurements at registration are not always good indicators for feasible reproductive performance, and that a more efficient method for body measurement should be developed in the near future in order to predict breeding values of reproductive traits such as age at first calving and calving interval, and longevity of replacement heifers and cows.

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Digested bacterial cell powder (DBCP) was prepared from Brevibacterium lactofermentum as an immunopotentiator containing peptidoglycan. In experiment 1, DBCP was given orally to post-weaning piglets. Diarrhea morbidity of piglets fed diets containing 0.01 and 0.03% of DBCP was significantly lower than that of nontreated control group (P<0.05). In experiment 2, DBCP was fed to sows and suckling piglets. Suckling piglets in DBCP treated group showed lower diarrhea morbidity (P<0.05) and significantly higher survival rate (P<0.01) than these in nontreated control group.

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Effects of tea saponin, cholesterol and oils on the growth and feed passage rates were investigated in Single Comb White Leghorn male chicks. Seven-day-old chicks were fed the experimental diets for 10 days in experiments 1 and 2. In experiments 3 and 4, 3-week-old chicks were allotted. The addition of graded levels of saponin to the basal diet caused progressive declines in growth rate and feed intake in experiment 1. These adverse effects were overcome by adding 1.0% cholesterol simultaneously with saponin. Tea saponin did not suppress the hypercholesterolemia induced by dietary cholesterol. In experiment 2, the addition of 10% corn oil or coconut oil to the diet containing 0.5% saponin partly alleviated the growth depression. The alleviatory effect of corn oil was superior to that of coconut oil but inferior to that of 1% cholesterol addition. In experiment 3, saponin and cholesterol were introduced using capsules into the proventriculus to avoid the effect of the taste, and then chicks had free access to the commercial diet for 24h. Even in this case, the administration of 50 or 100mg saponin depressed feed intake. These effects were alleviated by the equal amounts of cholesterol if both supplements were simultaneously administered. In experiment 4, feed passage rate in the digestive tract was measured using chromium oxide. The force-feeding of the diet containing 1.0% saponin delayed the feed passage rate, which was entirely recovered by the concomitant addition of 1.0% cholesterol. Feeding 2ml corn oil together with the saponin-added diet significantly facilitated the crop emptying but much less effective as compared with the addition of cholesterol. These results indicated that the adverse effect of tea saponin and its alleviation by cholesterol or oils were associated with the feed passage rate rather than feed palatability.

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The effects of excess dietary choline, rapeseed meal and fish meal on the fishy tainted eggs of White Leghorn hens were studied. Single Comb White Leghorn hens at 96 weeks of age with high egg production rate were divided into four dietary groups of 10 hens each, and consumed a control diet for 10 days. After then, the control diet was successively switched to 0.46, 0.68 and 0.90% choline diets in the second group, to 5.0, 10.0 and 15.0% rapeseed meal diets in the third groups, and to 4.0, 80 and 12.0% fish meal diets in the fourth group at 10 days internals. The first group was fed the control diet throughout the experimental period. The eggs laid on the odd days were used for determination of trimethylamine (TMA), and those laid on the odd days on the experimental diets were used for sensory test. Body weight, feed intake and egg production rate tended to decrease with increasing dietary choline, rapeseed meal and fish meal levels. TMA in egg albumen was less than 5% of total TMA in egg. TMA in egg yolk ranged from 0.46 to 1.01μg/g yolk in all experimental diets and period, which were less than the threshold value, 1.05μg/g. No fishy tainted eggs in all dietary groups were detected by the sensory test.

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Comparison of mating structure of F1 in reference family on the efficiency of linkage analysis was investigated using Monte Carlo computer simulation. The genetic linkage map was constructed using a two generation reference population comprising of 24 full sib families and 192 progenies derived from a intercross between 12 F₁ sires and 24 F₁ dams. F₁ animals were produced by crossing three grandsires from a different family line with six grandams from another family line. The mating of F₁ was considered to be (1) avoiding sib mating, (2) random mating and (3) full sib mating. A chromosomal map length of 1.2 Morgans was assumed. The average interval between markers was 0.05, 0.10, 0.15 or 0.20 Morgans and all DNA markers or genes had two allelles. The considered markers were placed at regular or random intervals on a chromosome. The marker alleles of each initial population were fixed or random with a 0.5 expected frequency. Chromosomal map length and recombination rate between markers with the lod scores (Z) were estimated using genotypic data from the reference population. Full sib mating of F1 yielded the largest mean square error and avoiding sib mating yielded the smallest mean square error of chromosomal map length and recombination rate. Rate of 3<Z became higher in the order, (1), (2), (3). The difference between (1) and (3) increased with increase in average interval between markers on a chromosome.

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Methods for reducing inbreeding in selection programmes were compared using two generation experiment with Tribolium. Comparison was made among four schemes: I) individual phenotypic selection+random mating, C) optimum family index selection+random mating, CM) optimum family index selection+compensatory mating, and CE) family index selection with heritability slightly biased upwards+random mating. The selected trait was 21 days pupalweight. Pair mating with 10 individuals of each sex was carried out, and 4 progeny of each sex were scored from each pair. For each scheme, experiment was replicated 4 times. The data from each replicate was analyzed by REML method to obtain estimates of heritability and genetic means. Inbreeding coefficient was computed from pedigree. The results obtained were summarized as follows: (a) Because of the small scale of experiment, there was a large variation in estimates of heritability (0.00-0.88). (b) The largest genetic gain was obtained in scheme C, and the smallest in scheme I. Although the genetic gains in schemes CM and CE were smaller than that in scheme C, the reduction did not seem to be important. (c) Scheme C showed the highest inbreeding coefficient (14.9% at generation 2), and the inbreeding coefficient in scheme I was kept in the lowest level (7.9% at generation 2). Two schemes CM and CE reduced the inbreeding coefficient (10.6 and 9.1% at generation 2, respectively), compared to scheme C. The harmonic means of effective population size over two generations in schemes I, C, CM and CE were 12.4, 6.5, 9.3 and 12.1, respectively. From these results, it was suggested that the use of biased heritability is one of the simplest and most efficient methods for reducing inbreeding, especially in short-term selection programmes.

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The relation between carcass grade and fat accumulation was examined by estimating genetic and phenotypic correlations among carcass grade, backfat thickness and carcass cross sectional areas of subcutaneous fat, intermuscular fat and total fat. Carcasses of 326 fattening pig were graded and the cross-section cut between the fourth and fifth thoracic vertebra was photographed for each animal for analyses of fat accumulation. Areas of cross-section, subcutaneous fat and intermuscular fat were analyzed by computer image analysis and fat accumulation around the loin was graded for seam fat score (1-5). Slaughtering season (I; Aug.-Nov., II; Dec.-Jan. and III; Feb.-March) significantly affected age at slaughtering and subcutaneous fat area and all the traits examines in this study were affected by sex except for carcass weight. Comparisons of these traits also show that carcasses graded as "upper class" were of pigs which were slaughtered at younger age than those of carcasses of lower classes. Carcasses graded as "upper class" and "middle class" had thicker backfat, larger subcutaneous and total fat areas and a higher seam fat score than those graded as "ordinary class" although there were no significant difference in intermuscular fat area among the classes. Backfat thickness was highly correlated to subcutaneous fat area (rG: 0.69, rP: 0.61, genetic and phenotypic, respectively), total fat area (rG : 0.74, rP: 0.55) and seam fat score (rG: 0.80, rP: 0.38), however, its correlation to intermuscular fat area was found to be poor (rG: 0.37, rP: 0.17). These results suggest that it may be necessary to incorporate fat accumulation in the carcass cross section into the carcass grading system so that carcass intermuscular fat accumulation is evaluated.

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Two trials were conducted using Holstein bull calves purchased from a market at 1wk of age. In trial 1, 20 calves were used to examine the effect on water balance and fecal moisture content during wk 2 of daily amounts of milk replacer (500vs. 200g/d) with or without free access to solid feed (timothy hay and concentrate) from wk 1. In trial 2, the other 20 calves were used to examine the effect of the similar treatments on glomerular filtration rate (GFR) and reabsorption of water (RAOW) from renal tubules during wk 2. Both trials were conducted in a factorial arrangement by dividing 20 calves into 4 groups of 5 calves each. When water balance was determined in trial 1, difference of the sum of urine volume and fecal water excretion from the sum of water used to prepare liquid milk replacer, and moisture originally contained in dry milk replacer and ingested solid feed was designated as apparent water retention (AWR), because metabolic water and evaporation from the lung and body surface were not considered. Ingestion of solid feed and a larger amount of milk replacer resulted in a decrease in urine volume and an increase in fecal water excretion, independent of the amounts of milk replacer. Fecal moisture content also increased from 66-67% in calves received no solid feed to 76-77% in calves given solid feed from wk 1, independent of daily amounts of milk replacer. However, AWR was increased not only by the ingestion of solid feed but also by the larger amount of milk replacer. Results of trial 2 suggested that decrease in urine volume resulting from ingestion of solid feed was due to enhanced RAOW which occurred in spite of an increase in GFR.

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Three types of bacterial mix starter cultures (P2M 120, PLM 230, S 51) were used to make dry fermented sausages. Fermenting and ripening were carried out at a controlled range of 20 to 13.5°C and with a RH of 70-90%, respectively. The total aerobic bacterial count was 1.1×105/gin the control sausage and was 5.6×106-1.0×107/g in the experimental sausages at day 0. After 3 days, these numbers increased to about 108-109/g in the control and experimental sausages and maintained the number until 35 days. The pH values dropped rapidly to 4.8 on the PLM 230 and S 51 experimental sausages at 3 days. On the other hand, the pH of the control sausage dropped to 4.8 at 7 days and after that, the pH ranged from 4.6-4.8 on the control and experimental sausages. Coliform group disappeared at 3 or 7 days in experimental sausages and at 14 days in the control sausage. There was no significant difference on the proximate analysis among the four types of sausage. Protein, fat and ash content of the final products increased twice that of the original amount. The peptide content was highest in the S 51 sausage and the total free amino acid content was highest in the PLM 230 sausage. The PLM 230 sausage scored higher than the others on the sensory evaluation, and the control sausage scored the lowest.

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Digestibilities and nitrogen retention of non-gelatinized and gelatinized limed splits, and effects of the limed splits on digestibilities of nutrients were studied in colostomized chickens. Egg albumen (control diet), a 1:1 (on the basis of crude protein) mixture of egg albumen and non -gelatinized limed split (AS diet) and that of egg albumen and gelatinized limed split (AGS diet) were used as the dietary protein source. All diets contained 14% crude protein. Decreased feed consumption was observed in AS diet and AGS diet groups. There was no difference in digestibilities of nutrients among 3 groups, but nitrogen retention in AS and AGS diet groups was lower than in control group. Results obtained here indicate that more than 90% of limed split is digested by chickens irrespective of gelatinization and that the palatability of limed split should be improved for practical use.

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This study was conducted to examine effects of dietary cellulose levels on growth and nitrogen utilization in young chicks fed equal amounts of nutrients of a 15% protein diet. Body weight gain significantly increased with an increase in dietary cellulose level until 3.5%, then decreased linearly up to an inclusion of 20% of cellulose in the diet (3.5 vs. 0, 10 or 20%, P<0.05). Feed efficiency was not influenced by dietary cellulose levels from 0 to 5%, but decreased by 10% and more dietary cellulose levels(10 vs. 1.5, 3.5 or 5%, P<0.05; 20 vs. 0, 1.5, 3.5 or 5%, P<0.05). Nitrogen(N) retention, N retention rate and retention rate of absorbed N were significantly increased by 1.5% cellulose level (P<0.05), then significantly decreased by 3.5% and more dietary cellulose levels (P<0.05). Apparent digestibility of dietary protein was not influenced by changes in dietary cellulose level. It is concluded that the highest rates of growth and N retention and retention rate are obtained by 1.5% dietary cellulose, and lowered by 3.5% and more dietary cellulose levels when protein intake is restricted to 15% crude protein in chicks.

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