An important aspect associated with muscle growth and meat quality concerns the intrinsic properties of muscle connective tissue, particularly collagen. Using immunohistochemical and biochemical techniques, age related changes of intramuscular collagen in rat were followed in this study.
The thickness of primary muscle fasciculus increased from birth until 10-week-old rat. This change was agreed with that of the body weight of rat. In the one-day-old rat, some nucleus of a muscle cell were localized at the center of muscle fiber. The connective tissue were scattered in muscle. The dense compact perimysium was observed first at the age of 3 weeks. Type IV collagen already appeared in endomysium at the age of one day. Type I collagen in perimysium was observed at the age of one week. Type III collagen in perimysium was defined at the age of 3 weeks. It is likely to exist a relationship between compaction of perimysium and the occurrence of type III collagen.
The content of protein in muscule increased from birth until 4-weeks-old, then it reached plateau. On the other hand, intramuscular collagen also increased until 4-week-old but it lowered contrarily in mature rat. Total amount of intramuscular collagen at the age of 10 weeks and 7 monthes were about half of its at the age of 4 weeks. The ratio of intramuscular collagen to protein was higher (2 times) in very young (1 days-6 weeks) than in mature (10 weeks and 7 monthes) rats.
The percentage (60-70%) of intramuscular collagen solubilized by heating was very high and did not show the significant change with chronological age. Type I collagen chains were recognized in the SDS-PAGE of the solubilized fractions by heating, although the other bands including type III and IV collagen were not detected.

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It has been suggested that stress acting via the adrenal gland may play a role in the etiology of ovarian cysts in the sow. The purpose of the present experiment was to determine the effects of exogenous ACTH on the estrus and ovulation in the normal sow. Four sows which had displayed several estrous cycles of 18-21 days were used. Three sows received intramuscular (im) injections of 0.5IU/kg ACTH suspended in saline solution twice daily at approximately 09:00h and 17:00h, for 7 or 9 days beginning on Day 16 or 19 after ovulation. The response of the ovary and uterine cervix to the treatment was monitored by rectal palpation. Plasma estrogens, progesterone, cortisol and corticosterone were measured by radioimmunoassay. The remaining sow received a single im injection of 1IU/kg ACTH during the luteal phase. The first 3 sows developed ovarian follicles beginning around the anticipated date of the next estrus. Two sows displayed feeble estrus on Day 23 and 27, respectively, after a previous ovulation. The remaining sow failed to display post-treatment estrus, and mature follicles were found present. Ovulation in all sows was blocked and follicular cysts developed. Plasma estrogen concentrations were generally maintained on a low level, in spite of the involution of the corpora lutea, follicular development and formation of cystic follicules. In 2 of 3 sows, plasma progesterone values were also as low as in the normal follicular phase, except for one sow in which the level rose considerably with the luteinization of the cystic follicles. When a sow was injected with 1IU/kg of ACTH, plasma corticoid values peaked in half an hour after treatment and returned to the basal level at 9 hours. The plasma corticoid pattern was almost the same in the 3 sows which were given ACTH consecutively.
These results indicate that the sow exposed to various stressful stimuli may induce hypersecretion of ACTH, and that the preovulatory surge of LH may be suppressed through a feedback mechanism due to depressed estrogen secretion in developing follicles. Therefore ovulation may be blocked and follicles may become cystic.

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Four experiments were conducted 1) to measure the response of lysine, threonine, methionine, isoleucine and valine supplementation of a L-tryptophan 0.05% supplemented corn-soybean meal basal diet, and 2) to estimate the threonine requirement for growing pigs kept under practical ad libitum group-feeding conditions. Daily gain (DG) and feed conversion ratio (FCR) were used as response criteria. 1) Experiment 1, involving 24 pigs weighing approximately 25kg, measured growth response to the addition of L-lysine HCl 0.5% (0.4% free base), L-threonine 0.1% and DL-methionine 0.1% to the basal diet, which contained lysine 0.44%, threonine 0.39%, sulfur amino acids (methionine+cystine) 0.49%, tryptophan 0.15% and crude protein (CP) 10.7%. DG and FCR were 762g and 2.5, respectively, when the mixture of three amino acids was added, while DG was decreased to 524g and FCR increased to 3.2 by adding mixture devoid of lysine. A mixture lacking methionine drew no response, 738g and 2.6, respectively-while a mixture without threonine was intermediate, 619g and 2.8, respectively. 2) In experiments 2 and 3, we determined the threonine requirement for 20 pigs weighing approximately 24kg each. We measured growth response to the addition of L-threonine, 0, 0.05, 0.1 and 0.15% for experiment 2 and 0, 0.1, 0.15 and 0.2% for experiment 3, to the basal diet supplemented with L-lysine HCl 0.5%. DG and FCR changed linearly as the addition of L-threonine was increased to 0.1-0.15%. Further increases in the addition of L-threonine had no effect. Using DG and FCR as the response criteria, the calculated requirements for threonine were 0.51% and 0.49%, respectively. 3) In experiment 4, involving 16 pigs weighing approximately 29kg, we measured growth response to the addition of L-isoleucine 0.1% and L-valine 0.1% to the L-lysine HCl 0.5% and L-threonine 0.15% supplemented basal diet, which contained isoleucine 0.44% and valine 0.54%. There was no response to the addition of isoleucine and valine. 4) The results of these experiments suggest that lysine and threonine are the first- and second limiting amino acids in a 10.7% CP, tryptophan supplemented corn-soybean meal diet, which is not limitied in sulfur amino acids, isoleucine and valine.

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Sheep were fed lucerne hay alone or supplemented with a physiological dose of calcium propionate (10mmol/kg BW) and exposed to a thermoneutral (20°C) or a hot environment (30°C) in order to observe the effects of dietary propionate and of heat exposure on glucose disappearance rate and insulin response following the intravenous injection of glucose.
The blood glucose disappearance rate before feeding tended to be higher for lucerne hay with the calcium propionate diet than for the lucerne hay alone diet, but the blood glucose disappearance rate after feeding tended to be lower for lucerne hay with the calcium propionate diet than for the lucerne hay alone diet. Insulin secretion in response to glucose injection before feeding tended to be greater during heat exposure than under the thermoneutral condition regardless of diet, and after feeding it tended to be smaller for the lucerne hay with calcium propionate diet than for the lucerne hay alone diet, regardless of air temperature. These results suggest that both the rate of blood glucose utilization and insulin secretory response to exogenous glucose are influenced more by dietary conditions than by environmental heat exposure.

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The optimum gentle stirring time was estimated for effective operation of simultaneous removal of nitrogen and phosphorus from the swine wastewater by the modified aerated lagoon process. The experiment was carried out with four different stirring times, 0, 4, 6 and 8 hours. Other conditions were fixed; 3 hours for filling, 5 days for detention and 2 hours for settling. The results obtained showed that (1) the nitrogen removal efficiency increased to similarly high rates of 90% by 6 and 8 hours of gentle stirring, (2) the phosphorus removal efficiency also amounted to similarly high rates of 87-88% by these stirring times, (3) TOC and OD were not influenced by the gentle stirring time, and the TOC removal rates were 97% in all the processes and (4) SVI increased with the stirring time and was 71 by 8 hours of gentle stirring. From the results obtained, the optimum stirring time for efficient simultaneous removal of nitrogen and phosphorus by the modified aerated lagoon process was estimated to be approximately 6 hours. Practical application of this processto the treatment of a mixture of feces and urine is considered necessary.

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Rice straw (RS) was offered to three rumen fistulated wethers, alone or supplemented with soybean meal (SBM) at 100, 200 or 300g per day, to investigate the effects of SBM supplementation on the supply of nitrogen (N) and energy to the ruminal microbes, ruminal fiber digestion and voluntary intake of RS. Ruminal degradation of crude protein, organic matter and cell wall constituents (CWC) was measured by the in sacco technique. The SBM supplementation increased the degradability of crude protein, but had little effect on the organic matter degradation. The rumen degradable N supply, and the ratio of N and energy supply to the ruminal microbes were improved with the increasing level of SBM supplementation. The potential extent of ruminal CWC digestion was low for RS and it was not affected by SBM supplementation. Both rates of ruminal CWC digestion and passage of digesta from the rumen were increased slightly with the increasing level of SBM supplementation. The retention-time index declined with SBM supplementation, but still was high even at the highest level of SBM supplementation. The voluntary intake of RS showed a small increase as a result of 100g SBM supplementation, and leveled offthereafter. These results suggest that it is diffcult to increase the voluntary RS intake only by supplementation with N sources.

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Three rumen-fistulated wethers were used to study the effects of alkali treatment and soybean meal (SBM) supplementation on the voluntary intake of rice straw (RS). Alkali-treated rice straw (ARS) was prepared by sprinkling RS with a 4% NaOH solution. The straw was fed ad libitum and SBM was supplemented at the rate of 200g per day. Alkali treatment increased the ruminal degradability of crude protein. Supplementation of ARS with SBM further increased crude protein degradability and ensured a sufficient nitrogen supply to the ruminal microbes. By alkali treatment, the potential extent of CWC digestion in the rumen increased significantly (P<0.01), but the digestion rate decreased slightly. The supplementation of ARS with SBM greatly increased the digestion rate. The rate of ruminal passage of digesta increased by both alkali treatment and SBM supplementation. The retention time index of CWC in the rumen was the lowest in the SBM-supplemented ARS diet. The voluntary intake of ARS was higher than that of untreated RS. The ARS intake significantly increased by SBM supplementation. It is concluded that when RS becomes potentially more digestible by alkali treatment, nitrogen supplementation will greatly increase the voluntary straw intake.

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In investigations of the Indonesian native livestock in 1977, 1978 and 1981, a total of 212 native chickens consisting of 164 males and 48 females, was measured for 8 different body parts and their body weights. The principal component analysis was applied to the discrimination of this body measurement. Results of the principal component analysis indicate that: 1) There were no clear differences in the body size and shape between 8 chicken populations in Indonesia except the game type. 2) The game type of the male Madura and the same type of the male South Sulawesian called Bangkok composed the largest group in size, based on the discrimination afforded by the size vector (PC1). Some external genetic characters of 5, 845 native chickens were recorded at 11 provinces in Indonesia. From the results obtained, the following values were calculated: The frequencies (q) of genes controlling these morphological characters, the admixture (Q) of European breeds, the native gene content in the present-day native chicken population and the frequencies in the native chicken population not attributable to the inflow from European breeds (q^(N)). These results indicate that the Indonesian native chicken holds about 50% native genes on the average.

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This experiment was conducted to determine the effect of dietary pantethine supplementation on lipid accumulation and activities of lipogenicrelated enzymes in the liver, on total cholesterol content of the egg yolk, and on the egg production of laying hens fed isocaloric and isonitrogenous diets containing different cereals as the carbohydrate source, under 31°C of environmental temperature. Pantethine added at 200ppm to the experimental diets did not affect daily feed consumption, but improved egg production and egg weight. Its supplementation to the barley-soy (BS) and corn-soy (CS) basal diets significantly increased liver weight but significantly reduced liver triglyceride. Total liver cholesterol was significantly reduced when pantethine was added to the CS basal diet. In a like manner, pantethine supplementation significantly reduced the concentrations of triglyceride, β-lipoprotein triglyceride and estradiol-17β in the plasma. Total plasma cholesterol was significantly decreased when pantethine was added to the BS or CS basal diet. It also suppressed the activities of several lipogenic-related enzymes in the liver, particulary that of HMG-CoA reductase. Further, it decreased total cholesterol (mg/g yolk) in the egg yolk. However, egg yolk weight increased. Thus, the amount of total cholesterol relative to the egg yolk was not significantly affected. The concentration of plasma thyroxine tended to increase when the experimental diets were supplemented with pantethine. In contrast, those of calcium and phosphorus did not show any significant change.

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