The present experiment was conducted to determine the extent the performance of young laying hen was affected by dietary crude protein (CP) and metabolizable energy (ME) levels, preceeding a series of experiment to determine the requirement of each essential amino acid.
Seven hundred twenty pullets of a commercial strain were housed two birds per cage in an open convention-ventilated laying house and fed twelve diets ad libitum from 150 to 255 days of age. Three replicate (240 birds per replicate) were involved. Mean daily temperature ranged from 15° to 25°C during the experimental period. Experiment had a 4×3 factorial arrangement of treatment with four levels of CP and three levels of ME.
The diets were formulated for methionine, lysine and tryptophan to reach 85, 95, 105 or 115% of the NRC recommendations and contained graded levels of dietary ME (2, 700, 2850 and 3, 000 kcal/kg).
Significant diet differences for feed intake, egg production, egg weight, egg mass, body weight gain and feed conversion ratio were noted. Increasing the dietary energy resulted in reduced feed intake and a general tendency to increase energy intake. But feed consumption was not affected by dietary CP levels. Increasing the protein level of the diet resulted in increased protein intake but had no effect on energy intake. Throughout the whole experimental periods, egg production increased with increasing CP levels. The egg production rate was not affected by ME level till 192 days of age, but it tended to decrease with increasing ME level after that age. Egg weight increased with age on all diets. It increased with increasing CP level until 234 days of age, but was not affected by ME level throughout all experimental period. Since egg weight increased with age on all diets and egg production rate increased with increasing CP levels, egg mass also increased with age and by CP levels in the similar way as egg weight and production rate. As protein and energy levels increased, efficiency of feed utilization increased.
The present study showed that the CP level which maximized hen performance was 14.5% or more across all ME levels and on the protein requirements of laying hens indicated that for maximum production of about 90%, hens required about 18 grams of protein per day. Present experiment also have suggested that in a moderate environmental temperature (from 15° to 25°C) ME levels of 2, 700-2, 850 kcal per kg diet might give economical results. The daily energy requirement of the hens for maximum production of about 90% ranged from approximately 310 to 330 kcal ME per day.

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The enzyme activity and ultrastructure of osteoclasts in medullary bone cultured in the presence of calcitonin were examined using laying hens during the bone resorptive phase when the egg is in the shell gland of the oviduct. Before and after culturing in the absence of calcitonin, osteoclasts on the surface of medullary bone matrix showed strong acid phosphatase (ACP) and succinate dehydrogenase (SDH) activity and moderate lactate dehydrogenase (LDH) activity. These cells had a well-developed ruffled border adjacent to the bone matrix. In the presence of calcitonin, ACP, SDH, and LDH activity of osteoclasts decreased after 12 hours of culturing. The ruffled border disappeared within 1 hour. The clear zone developed near the bone matrix after 12 hours. These results suggest that calcitonin directly inhibits osteoclastic bone resorption in the medullary bone of laying hens during the bone resorptive phase.

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The objective of the present study was to compare the behavior and production performance of laying hens housed in cages with three different types of cage front. Thirty-six commercial laying hens were divided into 3 groups of 12 each. They were subjected to the following types of cage front with 2 birds per cage (474 cm²/bird), according to the Latin square methods: C, conventional wire mesh front; V, vertical wire front; H, horizontal wire front. Each experimental period consisted of 2 weeks. The proportion of birds performing each behavior (eating and drinking, preening, walking, and resting) in C, V and H cages was almost the same. The production performance was not affected by the type of cage front. However, the frequency of simultaneous eating by the cage mates was significantly higher in H cages than in C cages. The significant behavior transitions from aggression to walking, and walking to eating were observed in C and V cages. In H cages, direct transitions from aggression and walking to eating were significant. The transition from pacing to eating was significant in C and V cages, but not in H cages.

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The effects of age on sulfur-containing amino acid (SAA) requirement of broilers were studied using body weight gains and feed conversion ratio as main criteria.
In Experiment 1, the basal diet contained 20.7% of CP and 3371 kcal/kg of ME. Methionine was added in the range of 0 to 0.5% substituting for the same amount of glutamic acid to make 6 diets with graded levels of SAA. Broiler chicks aged 4 and 24 days old were fed ad libitum the experimental diet and water for 20 days. The body weight and feed intake were recorded on the 10th and 20th days on the experimental diet.
In Experiment 2, the basal diet contained 18.6% of CP and 3175 kcal/kg of ME. Methionine was added to make 6 diets with graded levels of SAA by the same method as in Experiment 1. Broiler chicks aged 4 and 21 days old were fed ad libitum the experimental diet and water for 10 days. The body weight and feed intake were recorded on the 10th day.
In Experiment 1, the body weight gain increased and then tended to decrease without a significant difference with the increase of methionine addition in all experimental periods. The maximum body weight gain was achieved at 1.14, 1.11 and 1.12% of dietary SAA levels from 4 to 14, 14 to 24 and 4 to 24 days, and 1.03, 0.99 and 1.00% of dietary SAA levels from 24 to 34, 34 to 44 and 24 to 44 days, respectively.
The feed conversion ratio at the lowest SAA level did not fit to a linear line. Except this point, it decreased and reached the minimum level at 1.18, 1.08 and 1.10% of dietary SAA levels from 4 to 14, 14 to 24 and 4 to 24 days, and 1.05, 1.02 and 1.03% from 24 to 34, 34 to 44 and 24 to 44 days, respectively.
In Experiment 2, the body weight gain and feed conversion ratio showed the same tendency as in Experiment 1. The maximum body weight gain was achieved at 0.97% from 4 to 14 days and at 0.89% from 21 to 31 days. The feed conversion ratio reached the minimum level at 0.97% from 4 to 14 days and at 0.93% from 21 to 31 days.
The average requirements determined from body weight gain and feed conversion ratio decreased with increase of age in both experiments.

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Chicken growth hormone (cGH) was purified from fresh broiler pituitaries by alkali extraction, ammonium sulphate precipitation, gel filtration and ionexchange chromatographies, and chromatofocusing, with a yield of 698 mg/kg of pituitary glands.
The purified cGH was shown to be homogeneous by polyacrylamide gel electrophoresis (PAGE) and the relative mass of it was estimated to be 22000 by sodium dodecyl sulphate (SDS)-PAGE. The isoelectric point of the cGH was 7.8.
When this cGH was injected into hypophysectomized chicks, it increased the width of tibia cartilage and erythrocyte numbers in circulation compared with those in saline-injected controls.

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The weight of testis of the guinea fowl under 12L:12D and 6L: 18D was found to be greater at 30 weeks of age than that under 18L: 6D, although smaller at 10 and 20 weeks of age. The age at first egg-laying under 12L: 12D was 283 days which was the longest among the groups. It was about 157 days and about 129 days and 129 days longer under 12L: 12D and 6L: 18D than that under 18L: 6D or 14L: 10D, respectively. The weight of the first egg and of its yolk was greater in hens under 12L: 12D or 6L: 18D than those under 18L: 6D or 14L: 10D. The greater testicular growth and the remarkable delay in the onset of egg-laying in hens under 12L: 12D and 6L: 18D may be characteristic of the guinea fowl.

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The influence of fasting and refeeding on protein, DNA, RNA and mRNA contents in the liver of chicks was investigated.
Total mRNA was purified from total RNA by using modified Poly (U)-Sepharose affinity chromatography. The mRNA content was determined by measuring the absorbance at 260nm and polyadenylic acid (5') was used as a standard.
Total protein, DNA and RNA contents in the liver were reduced by fasting and were increased by refeeding although they remained to be significantly lower than the control. The relative amount of mRNA was unchanged by both fasting and refeeding. Food deprivation for 3 days decreased total mRNA content which was recovered by the following 3-day-refeeding up to the control level.
The significant influence of fasting and refeeding was not observed in RNA: protein ratio. This unchanged ratio suggested that, at least, food deprivation and refeeding did not change the relative concentration of hepatic RNA, which can be regarded as the site of protein synthesis. Although there was no significant difference in mRNA: DNA ratio between 3-day-fasting and control groups, the ratio in the refed group was higher than that in the age-matched control group. The apparent increase in mRNA: DNA ratio by refeeding would result from the lower DNA content than control, and this result could lead the possibility of enhancing the transcriptional step and/or the stability of mRNA molecules by fasting and refeeding.

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Three experiments consisted in each two treatment and one experiment were conducted to reduce bacteria contaminating working boots wore for daily feeding management of broilers. Sterilized boots were worn at beginning of the each experiment.
In Exp. 1, the foot baths which were filled with disinfectant orthodichlorobenzene solution, were prepared at the entrance of each house. When operators went in and out the houses, their working boots were dipped into the bath. One week after, 10^4.7, 10^4.8 and 10^4.6 per cm² of bacteria were detected from bottom, heel and toe of the boots dipped to the baths, respectively. On the contrary, 10^4.8, 10^5.0 and 10^4.4 of bacteria per cm² were detected from the corresponding parts of control boots, respectively, which were not dipped in the bath. No significant differences were observed between each boot part of two treatments.
In Experiments 2 and 3, effects of soaking the boots to the same kind of disinfectant solution and washing them by rubbing with the solution were examined. The boots were soaked into the solution 15 hours from 5 p.m. at termination of daily work to 8 a.m. of next morning. No effect was observed on reduction of bacteria contaminating the boots after soaking. Reduction of bacteria was observed on heel and toe but no reduction on bottom of the boots washed with disinfectant solution. Number of bacteria detected from these three parts of the boots soaked or washed were more than 10^3.3 per cm². No reduction of bacteria also observed when the boots were soaked the fresh disinfecant solution (Exp. 4).
Results of the experiments indicate that no any easy technique is found to reduce bacteria contaminating working boots.

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During past three decades, OKAMOTO has maintained quail lines selecting for large and small size. Those lines have been already maintained over 60 generations. Body size is distinctly different between the lines as well as some physiological traits. At 10-week-old, average body weight of large (LL) line is 3.3 times that of small (SS) line. The SS line shows higher values in muscle protein turnover rate, skeletal muscle proteinase activity, oxygen consumption, body temperature and carbonic acid production. Despite these distinct differences between lines, the degree of differentiation estimated from genetic distance based on gene frequencies at several polymorphic protein loci is not obvious. In this study, we compared DNA fingerprinting (DFP) to reveal the genetic structure of the quail lines including random bred (RR) control line. Results are as follows. 1) DFP of individual quail showed characteristic pattern and individuals could be distinguishable from each other even within a line, 2) no commonly shared DFP band was observed among 18 quails examined, 3) each line had peculiar DFP pattern, from which we could construct a dendrogram classifiable into three groups consistent with each line, 4) the proportions of commonly shared bands between individuals (BS value) were 0.62 for LL line, 0.79 for SS and 0.43 for RR, while the value between lines was 0.37, which was one half that of within lines, and 5) inbreeding coefficients estimated from BS values were 0.44 for LL, 0.69 for SS and 0.37 for RR and corresponding values estimated from the formula F=Δ1/2 Ne were 0.73, 0, 72 and 0.52, respectively.

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