The variances of muscle fiber sizes among sampling positions were studied by measuring the cross-sectional areas of individual fibers. Seven muscles were obtained from four steers of Holstein which were grouped into two different body weights. The number of sampling positions was from 3 to 5 in each muscle. Tissue sections were stained with eosin only. Crosssectional areas of one hundred muscle fibers in each sampling position were measured using an image analyzer. Subsequently, the means of these 100 measurements were statistically analyzed for each sampling position. The effects of body weight, cattle, muscle and sampling position in seven muscles were significant. The means of cross-sectional muscle fiber areas varied significantly among cattle and among sampling positions in each muscle. Only in the m. deltoideus, the means of muscle fiber areas of the sampling positions 3 and 5 were the largest and the smallest in all the cattle, respectively. In the m. longissimus, the means of muscle fiber areas of superficial sampling position were significantly smaller than those of profound sampling position. In the m. longissimus and m. semitendinosus, the distribution patterns of muscle fiber sizes showed large differences among the sampling positions in all the cattle. Proportion of their muscle fibers of 1000-5000μm² in the cross-sectional area was 80% or more. In the m. psoas minor and m. rectus thoracis, differences in the patterns of distribution were small in all the cattle. Their muscle fibers of less than 1000μm² were over 50% and muscle fibers of over 2500μm² were not determined. In conclusion, the variance of the means of cross-sectional muscle fiber areas among the sampling positions was considerably large. The difference in the distribution pattern of cross-sectional muscle fiber area also became larger among the sampling positions when the number of thick muscle fibers increased. It was suggested that increasing the number of sampling positions was important to reveal the effects of body weight and cattle on the cross-sectional area of muscle fibers.

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Unsterilized wheat straw was treated with a basidiomycete, Pleurotus salmoneostraminus, to observe changes in its chemical composition and dry matter digestibility. Collection of the substrates was conducted at the following stages: (1) wet wheat straw after soaking (control), (2) fungal treatment on the 30th day (semianaerobic), (3) fungal treatment on the 60th day (after fruiting; aerobic after the 30th day), (4) fungal treatment on the 60th day (semianaerobic), and (5) wet wheat straw without fungal treatment (semianaerobic, negative control). With Pleurotus salmoneostramineus treatment, wheat straw changed to bright yellow. However, wet straw without fungal treatment turned dark with the unidentified mould of indigenous microbiological flora on the wheat straw. NDF content tended to decrease as the duration of fungal treatment lengthened, and a significant decrease in aerobic condition was observed on the 60th day in comparison to semianaerobic condition. No marked change in ADF and ADL content was observed. The value of IVDMD decreased on the 30th day and increased on the 60th day. Higher values of IVDMD were observed on the 60th day in aerobic condition than in semianaerobic condition, although the difference was not statistically significant. Wet straw without fungal treatment showed a marked decrease in IVDMD values, although the changes in NDF, ADF and ADL content were small in comparison.

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Three experiments were conducted to determine the effect of dietary lysine and arginine on growth performance and tissue cholesterol levels in chicks fed the wheat gluten diet containing 20% crude protein. In Experiment 1, graded levels of lysine were added to the basal diet containing 0.34% lysine. The best growth performance was achieved by 0.5% supplementary lysine (in total 0.84% in the diet) and both deficient and excess levels of lysine elevated serum cholesterol level in chicks fed the cholesterol-supplemented diet. The result of Experiment 2 showed that arginine was the second limiting amino acid of the wheat glute n diet and supplementation of arginine along with lysine further reduced the serum cholesterol level in cholesterol-fed chicks. In Experiment 3, chicks were given the cholesterol-added diets containing excess lysine and/or arginine. Supplementation of 1% to 3% excess lysine increased serum cholesterol levels with concomitant growth retardation. These deleterious effect was completely alleviated by 3% excess arginine. Supplementation of 6% excess arginine was toxic for chick growth rate but it was still effective in reducing serum cholesterol levels, which were not affected by excess lysine addition. The extent of hyper-and hypocholesterolemic effect of lysine and arginine in excess, respectively, was not proportional to their supplementary levels in the diet, so that the dietary ratio of lysine to arginine was not a determinant factor regulating serum cholesterol level.

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Chemical and microbiological qualities of on-farm manufactured "Valencay" were evaluated. Samples from 12 cheeses ripened for 5 weeks were analyzed within 5 weeks after manufacture. The average values for protein, fat, carbohydrate and ash content were 15.71%, 20.40%, 1.79% and 2.02%, respectively, and the ripening rate (water soluble N/total N) value was 59.13%. Free amino acid composition was characterized by high leucine, glutamic acid, phenylalanine, proline and valine content. The most dominant species of lactic acid bacteria identified were Lactobacillus plantarum, Lb. casei subsp. 'pseudoplantarum' and Lb. curvatus.

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The aim of the present study was to investigate the stability of binding mutagenic tryptophan pyrolysates such as Trp-P1 and Trp-P2 to Lactobacillus casei subsp. casei R-52 cells. Stability was estimated by quantifying the amount of Trp-P1 or Trp-P2 dissociated from R-52 cells bound with Trp-P1 or Trp-P2 under the presence of trypsin or bile acid, or various pH conditions (pH2.0-8.0). The addition of trypsin to the assay system did not affect the dissociation of Trp-P1 or Trp-P2 from the cells, whereas the addition of oxgall to the system caused obvious dissociation. Under the presence of 0.3% oxgall, the dissociation rates of Trp-P1 and Trp-P2 were nearly 50% and 85%, respectively.

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Purification of lymphocytes of newborn calves aged from 0 to 14 weeks old was attempted by centrifugation with different densities (1.067, 1.077, 1.087, 1.079 and 1.107) of Ficoll-diatrizoate(F-D) fluid. When the dencity of 1.107 was used, the highest yield and purity of lymphocytes and the lowest monocyte contamination were obtained from samples of all aged calf tested. We concluded that 1.107 was the optimum density of F-D fluid for the purification of lymphocytes of newborn calves instead of 1.077 or 1.087 that were used for adult cattle.

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The responses of plasma insulin and growth hormone (GH) concentrations to the different intraruminal administration time duration of propionate were examined in non-lactating Holstein cows. Propionate (10mmol/kg body weight; P) was administrated for different time duration of P/1min, P/60min or P/120min into the rumen via rumen canula. Saline was injected as the control. Plasma concentrations of propionic acid, glucose, insulin and GH were measured at 20min intervals during the period 0min to 180min after the beginning of administration. The plasma propionic acid concentration elevated transiently and reached the peak value (P<0.05) at 20min after the beginning of the P/1min administration. The plasma glucose concentration dropped and reached the lowest value (P<0.05) at 60min in the P/1min administration. Settled elevations were observed in the plasma insulin concentrations in P/60min and P/120min administrations. However, the elevation of plasma insulin concentration in P/1min was transient. The area under response curve (AUC) of insulin in P/60min administration was greater (P<0.05) than that of any other administration. The plasma GH concentrations lowered (P<0.05) in P/1 min and P/60min administrations. Though AUC of GH in all propionate administrations were smaller (P<0.05) than that of the control, no significant difference was observed among the different time durations. These results indicate that settled elevation in plasma propionic acid has stronger stimulative effect on insulin secretion than transient elevation. The results also indicate that intraruminal propionate administration suppresses GH secretion without any relationship to its administration time duration.

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It is necessary to obtain information on economic values of traits used as selection criteria for improvement of beef cattle. However the economic values of carcass traits differ with market trend and other production circumstances. This study was made to investigate how the economic values of carcass traits were affected by the trade liberalization of beef imports and the fluctuations in price. The ordinary economic weights (partial regression coefficients) and standardized economic weights (standard partial regression coefficients) were derived from carcass of 8, 107 Japanese Brown steers from 1988 to 1992 by using multiple regression analysis. The four regression models with different dependent variables, i. e. carcass unit price, carcass sale price, dairy revenue increase and profit, were obtained by months within each year. These dependent variables can be regarded as aggregate genotype in selection indexes. The carcass traits considered as independent variables in the models were carcass weight, marbling score, ribeye area, rib-thickness and subcutaneous fat thickness. In 6 of 8 cases, the ordinary and standardized economic weight of carcass weight significantly decreased with the year. All the ordinary economic weights of marbling score increased in the course of years and also tended to increase at the end of years. Further, the standardized economic weights of marbling score increased with the year, when daily revenue increase, carcass sale price and profit were taken as ependent variables. With respect to rib-eye area, the year effects on the ordinary economic weights were significant sources when daily revenue increase and profit were taken as dependent variables and the same effects on the standardized economic weights were significant for all dependent variables. The year and month effects on the ordinary and standardized economic weights of rib thickness and subcutaneous fat thickness were not significant. The results showed that the economic importance of marbling score (a quality trait) remarkably raised but that of carcass weight (a quantity trait) droped during the five years before and after trade liberalization of beef imports, although Japanese Brown has been characterized by larger quantity traits.

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