A total of 997 Landrace pigs were ultrasonically scanned from first to fifth generations (G1 to G5) to investigate some factor effects on the carcass traits of fat thickness (FT), intermuscular fat thickness (IMFT), muscle thickness (MT), M. longissimus thoracis area (MLTA), total muscle thickness (MmT) and rib thickness (RT). Each trait was measured at four positions on the left side part of the body at a constant weight of 90kg. The scanning positions were A to D from shoulder to midback. Positions A and C were about 5cm from the midline with positions B below A and D below C. Positions A, B and C, D were at the 5th and 13th rib sections, respectively. A combination of trait and position was used as a trait. For example, FT and MLTA on position A were defined as A-FT and A-MLTA, respectively. Most of the FT estimates were found to decrease from G1 to G5. MLTA increased from G1 to G5. A-FT, C-FT, A-IMFT, A-MT, B-MmT and B-RT of females were significantly higher than those of males. The selected group had significant thinner FT and larger MLTA than that of the non-selected group on positions A and C. Generation×sex interaction was significant for A-FT, C-FT, A-MLTA and D-RT. Generation×selection interaction was significant for FT on positions A, C and D, MLTA on positions A and C, and D-RT. The linear regression of fattening period was significantly negative for FT in all positions, B-MmT and RT on positions B and D.

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An MTT colorimetric assay was used to measure the mitogenic response of chicken peripheral blood lymphocytes (PBL) to T cell mitogens, Concanavalin A (Con A) and phytohemagglutinin (PHA). OD values obtained in T cell mitogen-stimulated PBL rose as the incubation times increased. The largest OD values (optimal concentrations) were observed at 0.1mg/ml of PHA concentration and at 31.25 to 62.5μg/ml of Con A concentrations, respectively. The results suggest that the mitogenic response of chicken PBL is maesurable by MTT colorimetric assay, although the data must be compared with values obtained by radioactive nucleotide incorporation assay.

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The protective effect of the oral administration of fermented egg white powder (FEWP) on experimental Escherichia coli infection was investigated in immunosuppressant-treated mice. After intravenous infection with E. coli (3.1×10⁶ CFU), cyclophosphamide reduced the survival rate from 100% to 25%. When FEWP was given once daily for 4 days before infection, the survival rate increased to 70%. Cortisone acetate also reduced the survival rate from 100% to 30%, but when FEWP was given once daily for 4 days before infection the survival rate increased to 65%. These results show that FEWP markedly enhanced resistance to E. coli infection in cyclophosphamide- and cortisone-treated mice one day after completing FEWP pretreatment.

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Effective population size is one of the most important parameters in the design of animal breeding programmes, because it is closely related to the rate of inbreeding, the variation of selection response due to random genetic drift and the chance of loss of favourable alleles. In Japanese beef cattle breeding, it has been pointed out that the effective population size is dramatically reduced by the intensive use of prominent sires. In this paper, the authors developed a method for maximizing effective population size under an intended genetic gain. In the method, mating frequency of each sire is assigned according to the expected progeny difference (EPD) using quadratic programming technique. The method was applied to the population of Japanese Brown Cattle in 1993. The results obtained are summarized as follows: 1) From the survey of the actual mating frequencies, the annual effective population size of Japanese Brown Cattle was estimated as about 20. In particular, a sire with the highest EPD for beef marbling score (BMS) shared 40% of the total number of matings. This intensive use was considered as the main reason for the small effective size of population. 2) The proposed method was expected to increase the effective population size by 50%, while keeping the present genetic gain in BMS. Comparison between the optimal and actual mating frequencies showed that there is plenty of room for improvement of mating frequencies in Japanese Brown sires. These results suggest that the proposed method gives a guide for the control of mating frequencies of sires.

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Responses of milk protein production to protein concentrate supplements were estimated using 12 dairy cows fed on an all-silage forage program. A concentrate diet corresponding to 70% of the crude protein (CP) requirement was given to them, and silages were given ad libitum (control). In addition to control feeding, soybean meal or fish meal equivalent to 30% of the CP requirement were supplemented. Using corn silage (Exp. 1), 6 cows were fed on control, soybean meal, and fish meal-supplemented feed in a Latin square design, each for 3 week period. In Exp. 2 in which grass silage was used, the other 6 cows were fed on control, soybean meal, and fish meal supplemented-feed in a Latin square design, each for 16 days. Total N, casein N, whey N, and non protein nitrogen (NPN) were measured from milk samples taken in the last 2 days of each period. Venous blood samples were taken immediately before morning milking in the last days of each period, and plasma free amino acid, glucose, acetate and 3-hydroxybutyrate were analyzed. 1) Milk total N (milk protein) level was improved by soybean and fish meal in grass silage feeding, but not in corn silage feeding. 2) The percentage of casein N in total milk N was not influenced by the supplements. The percentage of NPN increased and whey N slightly declined via the protein supplement. 3) Plasma urea level increased significantly due to the supplements, but the other metabolite levels were not influenced. Soybean meal and fish meal supplementation caused an increased proportion of essential amino acids in plasma total amino acid levels. 4) Different lactation responses to protein supplements were confirmed between corn silage and grass silage feedings.

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The total infusion of nutrients was examined in sheep via the technique of continuous alimentation. Four abult Suffolk sheep fitted with a permanent ruminal cannula and a simple Tshaped duodenal cannula were used. A peristaltic pump was used to infuse solutions of volatile fatty acid triglycerides (VFA-TG) consisting of 70% triacetin, 20% tripropionin, 10% tributyrin on the basis of energy and minerals into the rumen, and casein solution into the duodenum. Each experimental period consisted of a common feeding period (non-infusion period) of 14 days when orchardgrass hay and concentrate ration was offered, and a changeover and adaptation period of 5 days followed by an infusion period of 14 days. The total daily amounts of energy and protein infused were equivalent to 1.5 and 1.2 times the maintenance amount, respectively. Ruminal and blood samples were withdrawn through the ruminal cannula and from a jugular vein catheter in each period. In the latter half of each of the non-infusion and infusion periods, glucosetreatment capacity was determined by the glucose load experiment, and insulin secretory response of glucose and the responsiveness of peripheral tissues to insulin were determined by the hyperinsulinemic euglycemic clamp (EGC) technique. Infusion of VFA-TG into the rumen caused a marked increase in ruminal TG concentration and a slight decline in ruminal pH values during the latter half of the infusion period. Intragastric infusion of nutrients resulted in slightly lower plasma ammonia and urea concentrations in comparison with non-infusion period. There was no significant effect of the infusion on plasma glucose, insulin, non-esterified fatty acid or triglyceride concentrations. Plasma lactic acid concentration was higher in the infusion period than in the non-infusion period (p<0.01). In the glucose load experiment, glucose treatment capacity and insulinogenic index (IGI) represented as a ratio of insulin increment to glucose increment were not significantly affected by the intragastric infusion of nutrients. In the EGC experiment, tissue responsiveness to insulin was slighty high in the infusion period. Although blood pH, P_co2, HCO₃^- and base excess tended to be higher during the latter half of the infusion period, sheep had no abnormal condition from a general clinical view. These findings may indicate that the technique of continuous infusion of total nutrients in the present experiment maintained sheep in a normal physiological situation, as in a common feeding, over a 2 week infusion period.

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An abnormal muscle in intra-muscular ossification is extremely rare. Ossification was observed in a whole cross section of bovine M. longissimus thoracis by direct X-ray photography. This sample showed a high pH value of 7.05, and the proportions of moisture and solid matter content were 83% and 12.6%, respectively. Hydroxyprorine, prorine and glycine content, which are rich in collagen fibers, were very much higher in the abnormal muscle than in the normal sample. Microscopic observation showed that the tissues were composed of spindle cells, not typical muscle fibers, and were similar to connective tissues observed by histochemical staining. However, the peripheral muscle, M. trapezius thoracicus, didn't contain any solid matter and its amino acid composition was not different from that of the normal muscle. When compared with M. trapezius thoracicus the abnormal M. longissimus thoracis, Ca and P content were approximately 25 times and 3 times higher, respectively. The ossified solid contained Ca, P and Sr levels similar to those in the costal bone, while Zn and Fe levels were 3-4 times as high. The gross structure of the solid was coral-formed, porous and shaped into branches. A sponge-shaped surface was observed under a scanning electron microscope. One of the probable reasons behind the ossification is the formation of the first connective tissues in the muscle, followed by the process of calcification or metaplasia. The tissues damaged by the ossification were repaired with connective tissues, and the ossification process was repeated causing it to spread into the whole muscle.

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Preweaning growth of a calf is the conjugated trait as calf growth and nursing ability. In addition, maternal effects may be composed of both additive genetic and permanent environmental effects. In this study, a model suitable to estimate genetic parameters for growth and nursing ability under grazing was investigated and the parameters were estimated for birth weight and preweaning daily gains in 657 Japanese Brown calves. These traits were analyzed using two different models (model 1 and 2). In model 2, maternal effect was devided into the breeding value and other effects, while not in model 1. Genetic parameters were estimated by the Derivative-Free Restricted Maximum Likelihood with the pedigree traced back 2 generations. The model 2 was more suitable to estimate maternal heritability for preweaning daily gain than the model 1. Direct heritability for birth weight was estimated as 0.40. Direct heritability for daily gain from birth until the months weighed increased as they grew older. The highest direct heritability (0.48) was estimated old at six months. The direct-maternal genetic corelations tended to be negative. The highest estimates of heritability and repeatability for maternal effect were obtained for daily gain until three months (0.31 and 0.42, respectively). It is concluded that the most probable producing ability (MPPA) for nursing ability in Japanese Brown cattle is predicted most appropiately by daily gain until three months.

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Fifteen Japanese Black steers engaged in progeny test of two sires were used in this study. Histological properties of biopsy materials taken from longissimus lumborum and biceps femoris muscles were observed at 9-10 months old. Intramuscular fatty tissue, perimysium deposits, was detected already at this age with individual difference in its development. In the longissimus, the histological volume score of the fatty tissue was related significantly to beef marbling score (BMS) of the carcass at 21-22 months old (p<0.05). Correlation coefficient between percentage of Type αW fibers and BMS was also significant (p<0.05). In the biceps, these coefficients were not significant. These results indicated that BMS could be estimated from the early observation of the perimysium deposits in the longissimus muscle.

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In order to characterize the processing of prolactin (PRL) by mammary cells, cells were loaded with PRL and PRL were analyzed by SDS-polyacrylamide gel electrophoresis. Receptorbound PRL had the same molecular weight (23, 000) as authentic PRL. No peaks with a molecular weight smaller than 23, 000 were detected. PRL in the PRL-receptor complex was protected from a proteolytic enzyme (s). It was concluded that PRL was degraded after dissociation from the receptor.

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