The changes in fatty acid composition in the lipid of bovine fat and muscle of beef cattle, caused by fattening via concentrate feeding after grazing, were studied. In experiment 1, 5 Holstein steers (D0) were slaughtered without fattening, and 3 steers (D1) were fattened for 208 days after grazing. The body weight and age of D0 and D1 were 526kg, 24 months, and 708kg, 31 months, respectively. In experiment 2, Japanese Shorthorn steers were fattened for 120 day (N1) and 172 day (N2) periods after being grazed. The number of cattle, their body weight and age were N 1:8 head, 600kg and 23.0 months; and N 2:6 head, 659kg and 24.5 months, respectively. (1) In regard to triacylglycerol fatty acid, C 18:0, C 18:3 and odd number carbon fatty acid decreased, while C 16:0, C 18:1, unsaturated fatty acid and the C 16:0/C 18:0 ratio increased, during fattening. (2) In regard to phospholipid in the muscle longissimus thoracis after fattening for a long period, C 16:1, C 18:1, mono-unsaturated fatty acid, C 22:4 and the C 16:0/C 18:0 ratio of fatty acid, and C 16:0 and the C 16:0/C 18:0 ratio of fatty aldehyde increased, while C 18:0, C 18:3, C 20:5, C 22:5 and ω3 of fatty acid, and C 18:0 of fatty aldehyde decreased. (3) The increase in unsaturated fatty acid and decreasein ω3 fatty acid, which are distinctive features of concentrate feeding-fattened cattle, were also recognized in the grazing cattle due to fattening after grazing.

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We graded each rib eye muscle (M. longissimus thoracis between the 5th and 6th rib portion) for its meat color of dressed carcasses of 764 Holstein steers fattened by a higher level of concentrate which were preserved in a refrigerator after slaughter. The percentages of each meat color grade were as follows: G1 (excellent) 1%, G 2 (very good) 16%, G3 (good) 46%, G4 (fair) 27%, G5 (poor) 10%. The sum of G4 and G5 occupied one third of all. In order to analyze the influencing factors on meat color grade, we investigated and measured 17 items (the fattening period, the initial weight, the final weight, the gain of body weight during fattening period, the daily gain, the distance for transportation from farm to slaughterhouse, the dressed carcass weight, the dressing percentage, the carcass storage times before meat color evaluation, the meat color (L^*, a^*, b^*) of rib eye muscle, the pH at rib eye muscle, the thickness of rib, the thickness of intermuscular fat, the thickness of subcutaneous fat and the rib eye area) of individual animals or carcasses. From the test for equality between two means, the significant differences were found in L^*, a^*, b^*, the thickness of rib, the thickness of intermuscular fat, the thickness of subcutaneous fat, the gain of body weight during fattening period and the distance for transportation from farm to slaughterhouse between some meat color grades. By applying these eight items as discriminant factors, we carried out the stepwise linear discriminant analysis. The results of the analysis suggested that the major factors influencing on meat color evaluation were L^*, the distance for transportation from farm to slaughterhouse, the thickness of rib, the gain of body weight during fattening period and a^*. The sufficient result of discrimination by these factors was not obtained. The meat color evaluation of rib eye muscle seemed to be also influenced by other items.

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An antiserum to prostaglandin (PG) E₂ and indirect immunofluorescence were used to examine immunohistochemically the presence of PGE₂ in hamster oocytes. Then, the percentages of fluorescent oocytes were calculated at different stages of folliculogenesis: primordial, secondary and antral follicles. Fluorescence, spread evenly throughout the cytoplasm, first appeared in 28.6% of the oocytes in large secondary follicles, though it did not appear in the oocytes in primordial and small secondary follicles. In antral follicles at 87, 63, 39 and 15hrs before ovulation, percentages of fluorescent oocytes changed slightly, showing 25.0, 36.4, 34.8 and 33.3% respectively. However, the percentages gradually increased during the period from 9 to 3 hrs before ovulation, showing 44.0 to 72.7%. From these results, it was clarified that hamster oocytes begin to have PGE2 at the stage of large secondary follicles. This also suggested that the PGE₂contained in oocytes plays an important role in their maturation after an LH surge.

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Experiments were conducted in which acetate and/or propionate were given to voles which weve fed a restricted diet for 30 days. Fifty-five voles, Microtus arvalis Pallas, of 12 weeks of age, with 30 to 40g of body weight, were divided into 3 groups, 1 control and 2 experimental groups. In the control group, voles were fed with a restricted diet of 6.5g of pelleted diet for herbivores. In the first experimental group, voles were fed with a restricted diet and were made to drink Na-acetate solution (20m moles/dl) ad libitum. In the second experimental group, voles were fed with a restricted diet including 0.5g of Ca-acetate and 0.1g of Ca-propionate. The results are summarized as follows. (1) The body weights of the control voles decreased by more than 10 grams. However, the body weights of the experimental voles were maintaind. (2) Blood glucose concentration of the control voles declined from the normal level of 70mg/dl to 33mg/dl. But blood glucose concentration of the experimental voles was maintained at a level of about 60mg/dl. (3) Hepatic glycogen contents in the control voles declined from the normal level of about 22mg/g to about 9mg/g. However, the contents of experimental voles were maintained at the level of about 25mg/g. (4) The concentration of acetone in blood increased rapidly in all groups, but the concentration of ketone bodys in urine did not increase.

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This study was conducted in order to evaluate the effects of a hot environment on the major mineral content in the milk of 20 Holstein lactating cows kept under natural conditions. Lactating cows were fed concentrate, beet pulp, corn silage, Italian rydgrass silage and hay. The major mineral intake of lactating cows was virtually adequate. Milk yield (23.2kg/day) in a hot environment (mean monthly temperature: 22.5-27.2°C) was larger than that (21.9kg/day) in an optimum environment (mean monthly temperature: 5.1-20.1°C). However Ca, P, Mg, and Na content in milk in a hot environment was less than in an optimum environment, and the ratios of Ca, P, Mg, and Na content in milk in a hot environment compared to an optimum environment were 92.1-95.0%. There were significant negative correlations between Ca, P, and Mg content in milk and milk yield, and a significant positive correlation between Na content in milk and milk yield in an optimum environment, but in a hot envionment there were significant positive correlations between P content in milk and milk yield. The decreases in Ca, P, Mg, and Na content in milk affected by heat stress were larger than those affected by the change in milk yield. The results suggest that the Ca, P, Mg, and Na metabolisms in lactating cows may be affected by heat stress and that their content in milk may decrease in a hot environment.

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In order to study the effects of thyroid hormone on liver glycogen, muscle glycogen and liver lipid, male chicks (White-Leghorn, Shaver strain) were surgically thyroidectomized at 11-12 days of age and injected with 1.5μg/10g body weight of L-thyroxine (T₄) at 27 days.
In the first trial, thyroidectomized chicks showed a remarkable increase in liver glycogen and liver lipid, and a decrease in muscle glycogen, compared to the control chicks. Thyroxine injection into the thyroidectomized chicks brought the marked decrease of liver glycogen accumulated and an increase in muscle glycogen at 24 hours after injection. However, contents of liver lipid remained unchanged by T₄ injection, suggesting that the response of liver glycogen to the injection was more rapid than that of liver lipid.
In the second trial, thyroidectomized chicks were made to fast for 24 hours after the T₄ injection. Liver glycogen decreased with time in both thyroidectomized and T₄ injected chicks and thyroidectomized chicks. The rate of decrease was more rapid in thyroidectomized and T₄ injected chicks than that in thyroidectomized chicks and the difference in liver glycogen contents were significant at 16 and 24 hours after injection. In thyroidectomized and T₄ injected chicks, muscle glycogen increased after the first 4-hour depletion, although in thyroidectomized chicks it decreased at a small rate and the difference in muscle glycogen contents were significant at 16 and 24 hours after the injection. The time course of increase in muscle glycogen appeared to be synchronized with that of a decrease in liver glycogen, suggesting that the thyroid hormone plays a role in the regulation of glycogen contents between the liver and muscle.

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Seventeen Japanese Black steers were used to examine the effects of finish weight (550kg, 600kg, 650kg), sires (2 groups) and concentrate during the latter fattening period (barley-fed group, corn-fed group) on carcass characteristics. During the growth of cattle from 550kg to 600kg, there was an increase of 18.4kg of muscle weight and 11.4kg of fat weight in the carcass. On the other hand, during the growth of cattle from 600kg to 650kg, there was an increase of 7.8kg of muscle weight and 25.2kg of fat weight in the carcass. Moreover, as the animals grew from 600kg to 650kg, there was a large increase in the fattening period and total TDN intake. These results suggest that it is more efficient to finish up to 600kg of live weight before the excess accumulation of fat in point of the growth rate and feed consumption. A significant effect of sires on the marbling score was obserbed. The barley fed group had larger muscle and bone weight than the corn fed group. There were significant interactions between sires and kinds of concentrate for slaughter age, total TDN intake, daily gain, cold carcass weight, dressing percentage, ribeye area and belly thickness except for the subcutaneous fat. The influence of the kinds of concentrate on feed intake, the rate of body weight gain and carcass characteristics changed for different sires.

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The experiment was conducted to compare the efficiency of 2 iron preparations, iron dextran and gleptoferron, and to determine the minimum requirement of injectable iron for preventing piglet anemia. In the first experiment, piglets were divided into 2 groups and one group was injected intramuscularly with 100mg iron from iron dextran at 3 days of age and another group was not treated. All piglets were not offered creep feed before 24 days of age. Hemoglobin and hematocrit were signficantly higher in the iron treated group than in the untreated group and red blood cell was rapidly increased in numbers by the iron injection. However, the prevention of anemia by 100mg iron was unstable later in the nursing period, when 9mg of hemoglobin/100ml blood was used as a minimum standard of adequate hemoglobin concentration. In the second experiment, the single injection of 1ml iron dextran (100mg iron) or gleptoferron (200mg iron) was done at 4 days of age and creep feed was offered after 7 days of age. Hemoglobin and hematocrit were higher in the gleptoferron group than in the iron dextran group, reflecting the difference of injected iron levels. The mean corpuscular hemoglobin and mean corpuscular volume were also related to the administered iron levels. In the third experiment, when in total 200mg iron was administered from iron dextran, no difference was observed in hemoglobin nor hematocrit as compared with those from gleptoferron. Thus, iron from iron dextran and gleptoferron have a similar efficiency for piglet anemia. The last experiment showed there was no difference in hemoglobin and hematocrit betwen 200 mg and 400mg iron injection.

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Simulated data were generated by a Monte Carlo computer simulation to study the effects of unbalanced data on sire evaluation and estimate of variance components. The simulated data included 40 sires and 100 herds, and subclass size was assumed to be distributed by Poisson distribution with mean observations of five. The degree of unbalanced data was set up according to the percentage of deleted subclasses: 0 to 90%. Estimation of variance components and sire effect prediction were carried out by i-MINQUE. The percentages of subclass deletion showed little effect on the estimated std. dev. (standard deviation) of sire effect. However, error std. dev. increased significantly as the percentage of subclass deletion increased. Estimated heritability was almost constant against the change of the deletion rate; whereas, the correlation between the predicted values and the expected values of sire effect decreased as the percentage of subclass deletion increased. This declining trend was becoming clear when the rate of deletion was more than 70%, and when heritability was less then 0.3. Consequently, if the target value of the correlation was more than 0.8, data filled with more than 10% subclasses was considered to be desirable with 0.3 heritability, data with more than 20% was desirable with 0.2 heritability and data with more than 30% was desirable with 0.1 heritability. Then the pattern of subclass deletion was analyzed to clarify the desirable data structure. The results showed that the types of deletion pattern had no effect on estimates of sire std. dev. and heritability; whereas, the correlated deletion pattern had accuracy as high as the random deletion pattern. Even if accuracy was compared between deletion patterns of selection, positive or negative correlated deletion patterns had relatively higher accuracy for the prediction of sire effect.

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We estimated the heritabilities of 24 body measurements and the genotypic and phenotypic correlation between them in Thoroughbreds. Data were obtained from 189 3-year-old Thoroughbreds of 68 sires which have more than two progenies. The data was analyzed by the least-square analysis using the Method 3 of Henderson (1953). The sire, sex and training place were contained as effects. As a result, the sire effects on the height at back, the height at breast, the length of cannon, the length of hind cannon, the thickness of breast and the circumference of girth were significant at above 5% levels, and the heritabilities of these 6 measurements were estimated to be high. The genetic correlations were from -1.84 to +3.17. However, some values were not reliable because these standard error is a large. Each correlation among the four measurements, that is the height at withers, the height at back, the height at croup and the circumference of girth, were estimated to be higher, ranging from +0.70 to +0.95. On the other hand, the minus correlations between the three parts, that is the height at withers, the height at back and the height at croup, and the body length were from -0.51 to -0.24. The phenotypic correlations were from -0.03 to +0.91. The high correlation among the three measurements, that is the height at withers, the height at back and the height at croup, and others were estimated. Especially noticeable is the correlation between the height at withers and the height at back which is estimated to be the highest.

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Relationship between the spatial distribution and social status in a herd of goats was studied. The herd composed of 18 Saanen goats, five adult billies, six adult nannies, four male kids and three female kids, was reared in a paddock of 2, 900m2 in which vegetation and topography were heterogeneous. Observations were performed during the daytime over four months from June to October. Behavior types (resting, eating and others) and positions of animals in the paddock were recorded onto the map of the paddock every five minutes. After observations, the map was divided into 167 grid areas (about 4.5m× 4.5m each) by lines, and the marks of individual animals in each area were counted and analyzed. Animals higher in social rank rested frequently, but ate less frequently, as compared with the subordinate goats. The data showed the evident relationship between social status and spatial distribution. The dominant goats used specific areas concentratively. For example, four dominant male goats used frequently the areas where wooden tables were located, and the frequency of the appearance of the four goats in the areas was about 60% of the total frequency in the herd. Whereas these four billies preferred several specific areas that were the same or close to each other, areas that each of them used most frequently differed individually. The spatial distribution of these dominant goats may be settled by the behavior pattern that they approach and avoid each other for their preferable areas.

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This experiment was carried out in order to investigate the effects of equalized or restricted water consumption on eating and rumination behaviour in sheep receiving only fresh or dried-grass in similar amounts. Daily time spent eating the dried grass tended to be fairly prolonged when water consumption was forcedly equalized to that for fresh-grass feeding, while the time spent markedly decreased due to restricted water intake after feeding dried-grass. The lag time after eating dried-grass tended to decrease due to the equalization of water consumption, and to increase somewhat via the restriction of water intake. The daily time spent ruminating did not change in the case of either feeding dried-grass with equalization or restriction of water consumption. The difference in water consumption did not affect the rumination index (time spent ruminating/100g D. M. eaten) and the rumination efficiency in sheep given access to forage diets with similar amounts of dry matter.

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Castrated Holstein male calves were restricted to 67 to 78% of ad lib. drinking water consumption for some periods (14 days) and a comparison was made to the period (14 days) with free choice of drinking water to investigate effect of the restriction on water balance, feed intake and digestibility in growing calves. The following results were obtained. 1) Water restriction reduced the amount of hay consumed but did not affect the intake of calf starter. 2) Coefficients of digestibility for dry matter, organic matter, nitrogen and crude fiber were not significantly affected by water restriction. 3) Water restriction reduced the quantities of water in the urine and feces. 4) In the course of rehydration, the amount of water drunk on the first day of ad libitum water was very high, but returned to the level for free access after 2 days on rehydration. During rehydration the change of quantity of water excreted in urine showed the same pattern as that drunk while fecal water increased gradually to the predehydration level.

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