The reported tryptophan requirement for the maximum performance of broilers ranges widely. The amino acid requirements are affected by many factors. In this experiment, the effects of age and dietary protein levels on the tryptophan requirement were investigated.
The experiment at 3 growing stages from 8 to 18, 25 to 35 and 42 to 52 days after hatching was conducted using female Arbor Acres strain broilers. The experimental feeds contained five graded concentrations of tryptophan in four levels of amino acid. At the end of each growing stage, the body weight gain and feed consumption were recorded.
The dietary tryptophan concentrations for the maximum performance of body weight gain expressed as a percentage of diet could be calculated clearly, but those from feed efficiency were uncertain values because of a large confidence interval. Those from body weight gain ranged from 0.111 to 0.159% of diet, had a tendency to decrease with age, and increased with increasing dietary amino acid levels. But those expressed as a percentage of dietary crude protein (CP) remained relatively constant with increasing dietary CP levels.

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Best linear unbiased prediction (BLUP) procedure applied to an individual animal model was used to predict breeding values for body weight at 7 and 30 weeks of age, egg weight in the 34th week and age at first egg in five selected female lines of White Plymouth Rock and four selected male lines of White Cornish chicken. The mixed linear model included year, house and sex as fixed effects. Individual inbreeding coefficients were also computed and used as a covariate in the analyses. Trends in inbreeding and breeding values were obtained by regression of average inbreeding coefficients and breeding values, respectively, on generation number.
The proportion of inbred chicken ranged from 1.2% to 65.5% but the highest mean inbreeding level of inbred chicken was only 0.07 for all the lines. Mean inbreeding levels were low even in the last generation of each line and no significant trends in inbreeding were found. From the first to the last generation the environmental effects generally increased for body weight at 7 weeks, egg weight and age at first egg but decreased for body weight at 30 weeks in most of the lines. However significant environmental trends were found in only three of the lines for body weight at 7 weeks. With respect to genetic trends, from the first to the last generation in most of the lines, average breeding values generally increased for body weight at 7 and 30 weeks but decreased for age at first egg. Average breeding values for egg weight generally increased in 4 of the lines but decreased in the remaining 5 lines. Significant genetic trends were found in 6 of the lines for body weight at 7 weeks only.
Realized heritabilities for body weight at 7 weeks ranged from 0.04 to 0.45 being somewhat lower than REML estimates except in 2 male lines.

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The aim of this study was to examine the mechanism by which the number of spermatozoa decreases in the oviduct of Japanese quail (Coturnix coturnix japonica) after copulation. We observed the vagina and uterovaginal junction (UVJ) histologically before and 0.5, 1, 3 and 6h after copulation. A large number of spermatozoa were observed in the lumen of vagina and UVJ 0.5h after copulation, followed by a markedly decreasing number in posterior vagina (pV) and UVJ 1h after copulation. Some of the spermatozoa in the vaginal and UVJ lumen showed an eosinophilic appearance. The number of leukocytes (polymorphonuclear leukocytes and lymphocytes) increased in the vaginal and UVJ lumen after copulation, and some of them were in close contact with spermatozoa. Spermatozoa were also localized in the mucosal epithelium and lamina propria just beneath the mucosal epithelium of UVJ 0.5h to 6h after copulation. These results suggest that the immunoreactions may be involved in the process of the decrease in the number of spermatozoa in the oviduct after copulation.

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For representing growth pattern, five non-linear growth curve models (Brolly, Bertalanffy, Logistic, Gompertz and multiphasic) were fitted to records of weekly body weight in egg-type chickens. In addition, the relationships with estimated parame-ters to productive characters were discussed.
Data were collected from two strains of White Leghorn chickens, which were selected for high and low yolk-albumen ratio. The fertiled eggs were obtained from hens of these lines with similar adult body weights. About 20% of predicted albumen weight of each egg as removed from half the number of collected fertiled eggs. The hens with records of egg production were used in this analysis. Goodness-of-fit for five models was judged by coefficient of determination (R²) and by Akaike's informa-tion criterion (AIC).
The chick in treated group was smaller than that in control group. The means of body weight at hatching were significantly estimated (6.2g in high-line, 6.9g in low-line). These differences disappeared after about 2-4 weeks of age.
The best fitted model for means of weekly body weight was multiphasic followed by Gompertz in the five growth curve models. The multiphasic model, however, overestimated the early growth (from hatching to 30 days of age).
The phenomenon such as diphasic growth curve was clearly observed from the growth rate of body weight on age (days). The first phase was until about 100 days of age. The second peak was not clearly recognized in the high line.
The mean of feed efficiency of the high line was significantly lower than that of the low-line, due to small size of eggs in the high line. No significant differences in the other productive traits were found between the two line.
The positive correlations were found between growth rate in phase 2 of multi-phasic model and egg production, whereas growth rate in phase 1 and in Gompertz model had negative relationships with egg production. The estimated parameters indicating mature weight were negatively correlated with the number of eggs and egg production rate.

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To evaluate the feed digestibilities measured using intestinal content of chickens, the contents of lower ileum and rectum were collected every 30 minutes from 1.5 to 8.0h after the force-feeding. The changes of feed digestibilities of the collected contents were measured and compared with those of the feces obtained from the chickens attached an artificial anus.
1. The amounts of content in lower ileum were small until 2.5h and after 7.5h after the force-feeding, but those were great from 3.0 to 7.0h after the feeding in all chickens. On the other hand, there is no relationship between the amount of contents in the rectum and time after the force-feeding.
2. The feed digestibilities except for crude fiber abruptly increased in content of ileum from 1.5 to 2.5h after the force-feeding. The digestibilities from 3.0 to 7.0h were comparatively stable and almost the same values as those of chickens attached an artificial anus. But, the digestibility showed a tendency to decrease after 7.5h.
3. The feed digestibility in content of rectum had a great variation with individ-ual chicken and changed with sampling time. The digestibility except for nitrogen free extract showed a tendency to be lower than those of chickens attached an artificial anus.
These results suggest that the measurement of feed digestibility with ileum contents is reasonable from 3.0 to 7.0h after the force-feeding.

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The objective of this study was to examine the relation of egg components to hatching, body, and its components weight of chicks. Two strains, which were selected to high and low yolk-albumen ratio, were used in this study. The hen of each strain was classified into two groups according to the largest and smallest albumen weight. In each group, eight hens were sampled and 9-12 fertiled eggs per hen were collected. About 30% or 35% of predicted albumen weight of egg of the former group (experiment I) and about 20% or 25% of the latter group (experiment II) were removed from two-third of collected egg before incubation. Hatching time was observed from 20th day of incubation, and was represented a difference from 21th day (0-hour). The day-old chicks were weighed, slaughtered and some intra-peritoneal organs were also weighed.
The egg component weights of fertiled egg were estimated from its egg weight and its hen's values. In both experiments, egg weight and ablumen weight of the low line were significantly larger than that of the high line, but the mean of yolk weight was smaller. The differences between controll and treated groups were not significant.
The similar values of hatchability were obtained from the control groups of both lines and experiments. But, the hatchabilities of the treated groups were significantly decreased, and this trend was clearly for the high line. Moreover, it was observed that the more amount of removed albumen from egg was more declining tendency in both lines.
Hatching time of the treated groups in the high line was slightly reduced, while the opposite trend was obseved in the low line.
The chicks in treated groups of both lines and experiments were smaller than in control groups. The means of body weight at hatching were significantly different (6 to 12g in high line, 7 to 8 g in low line). These loss in weight was approximated to removed albumen weight.
The measured organ weights were paralleled with body weight. The yolk sack weight of treated group in high line was not significantly decreased.

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Restriction fragment length polymorphism (RFLP) analysis of Japanese quail (Coturnix japonica) was performed using probe (F10) of chicken's major histocompatibility complex (MHC) class I, and the relationship between its RFLP pattern by enhanced chemiluminescence (ECL) method and Ly antigen types in Ly system was examined. The results obtained are as follows; (1) The absorbance ratio (260nm/280nm) of extracted genomic DNA by using NaCl-Saponin solution for hemolysis of red blood cell was 1.866±0.034 and the concentration was 2.83±0.76mg/ml. Besides, genomic DNA of 3.78μg was extracted from 1μl volume of blood. (2) RFLP pattern of DNA digested with Pvu II in RWL strain (Ly₁/Ly₁), PNN strain (Ly₂/Ly₂) and SBPN strain (Ly₃/Ly₃) revealed 18-19 pieces of DNA bands, and a band of 8.3kb was observed in RFLP pattern of RWL strain. (3) The 8.3kb DNA band might be inherited from parents to offsprings, but it was not detected in the WEP strain (Ly₁/Ly₁). (4) ECL method as a labeling method of the probe was a valuable technique in RFLPanalysis.

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