For the primary objective of changing egg components, a divergent selection for high and low yolk-albumen ratio was carried out over 12 generations. The selection was also relaxed for next 12 generations to confirm the establishment of the lines. This paper examined the responses to selection for yolkalbumen ratio as the changes of yolk weight and albumen weight. A random-bred population of White Leghorn chickens used in this experiment was hatched in 1969. Egg traits were measured from 8 to 9 months of age in every generation and then hens were selected for high and low yolk-albumen ratio. Proportions of selection were 1/3∼1/4 for females. The selection was relaxed from the 12th generation by constraining selection differentials close to zero for yolkalbumen ratio, yolk weight and albumen weight, provided that at least one female per family was randomly chosen. About 16 males were mated to females sampled from the same line with avoiding full-sibs and half-sibs matings. Amount of responses over 12 selected generations compared with foundation population for yolkalbumen ratio was estimated to increase to 10.17% (0.94% per generation) in the high line and to decrease to 9.81% (0.80% per generation) in the low line. Realized heritabilities that were estimated by regression on cumulative selection differentials were almost the same in both lines with the values of 0.226±0.019 and 0.230±0.021, respectively for the high and low lines, and 0.228±0.006 for the estimation by the differences between lines. The differences between lines for yolk weight increased to about 2.5g at the generation 9 and then stagnated. Those for albumen weight continuously increased after generation 2 (0.818g/generation). These changes suggested that selection responses for yolk-albumen ratio depended on the changes in yolk weight and albumen weight in the early generations, and the increases of albumen weight in the late generations. When selection was relaxed, significant increases in yolk-albumen ratio (0.41% per generation) were observed only in the low line. In the high line, the changes were in the range of 55∼60%. The changes in yolk weight and albumen weight were not significant in the high line. The low line showed the increases in yolk weight and significant decreases in albumen weight (0.26 per generation). The differences between lines for these traits were significantly decreased, indicating the phenomenon of regression to foundation population. However, these changes were caused by the changes in the low line. These results suggested that selection response has approached the limitation in increasing yolk-albumen ratio. The reduction in yolk-albumen ratio would relate to a necessity that yolk weight could not be decreased beyond the under biological limit.

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We have examined the influence of food deprivation on the activity of chicken serum to stimulate protein synthesis of chicken embryo fibroblast (CEF). Chicken serum, whose activity to synthesize protein was compared with that of fetal calf serum (FCS), was collected from 6-week-old chickens food deprived or allowed free access to a commercial diet for 2 days. CEF was derived from 9-day-old chicken embryos. The concentrations of serum were varied at 0, 2, 5, 10 and 20% (v/v) in the culture medium. After incubating for 54 h, protein synthesis was measured by the incorporation of L-[2, 6 -³H] phenylalanine from medium into protein during further 18 h. The lowest value for protein synthesis was observed in CEF cultured in absence of serum. Even if any types of serum were supplemented in the culture medium, protein synthesis increased with rising serum concentrations from 2 to 20%. When the serum concentration was above 10%, protein synthesis of CEF cultured with food-deprived chicken serum was significantly lower than those in other treatments. There was no significant difference in protein synthesis between well-fed chicken serum and food-deprived chicken serum supplemented with recombinant chicken insulin-like growth factor-I (IGF-I) at 50μg/ml. It was concluded that the reduced protein synthesis of CEF cultured with food deprived chicken serum was, in part, because the decrease in blood concentration of IGF-I.

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The density and distribution of noradrenergic (NA) and acetylcholinesterase-positive (AChE) nerves in the extracranial part of the internal carotid artery (eICA) and cerebral arterial tree of the Japanese quail were investigated using specific histochemical techniques. The eICA and the major cerebral arteries in this bird were richly supplied with a large number of NA nerves, but had a very poor or no supply of ACNE nerves. The cerebral arteries located more caudally than the proximal part of the anterior ramus were generally devoid of ACNE nerves, while the internal ethmoidal artery (IEA) was usually equipped with fiber bundles positive for AChE. The above finding suggests that all or nearly all of cerebral perivascular AChE nerves path through the ethmoidal foramen, and project to the cerebral arterial system via the IEA. This differs from the cerebrovascular NA Innervation in that NA nerves enter the cranial cavity through the IEA, ICA and the vertebral artery, mainly via the ICA. A significant finding is that a few AChE nerve cells are present on the major cerebral arteries of the internal carotid system, mainly the IEA. Thus, the quail cerebral arterial system is dually innervated by the axons from extrinsic and intrinsic AChE neurons in some individuals. The unique NA and AChE innervation in the eICA and cerebral arteries of the quail must be considered in relation to the presence of NA and cholinergic vasomotor mechanisms responsible for the regulation characteristic of cerebral circulation in this bird.

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The aim of this study was to examine the mechanism by which the follicles become ovulable. Pregnant mare serum gonadotropin (PMSG)-priming and hypophysectomy make follicles ovulable. We observed ultrastructural changes of follicular germinal disc region after PMSG-priming and hypophysectomy and determined a common feature of ovulable follicle. In the second largest (F2) and smaller follicles of control birds, those are not ovulable, many smooth endoplasmic reticulum-like vesicles were localized in germinal disc and cytoplasmic process of granulosa cells formed gap junctions with oolemma. On the other hand, in the germinal disc region of large follicles of PMSGprimed and F2 follicle of hypophysectomized birds which are ovulable, gap junctions between cytoplasmic process of granulosa cells and oolemma were disintegrated, and vesicles in germinal disc were shrunken. We assume that these histological changes in the granulosa cell-to-oocyte communications and smooth endoplasmic reticulum may be involved in the process by which a follicle becomes ovulable.

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Sequential morphological changes and immunohistochemical investigation of apoptosis in the bursa of Fabricius in the immature chicks with a single injection of dexamethasone as a glucocorticoid were studied.
Dexamethasone treatment resulted in bursal atrophy and reduction of the number of bursal lymphocytes, and these reductions were more markedly in the medulla than in the cortex. The reduction in cell size and a condensation of chromatin were found. Immunohistochemically apoptic positive cells were increased after treatment and characteristical C-Shape signals were found around the nucleus in the apoptic positive cells.
These results suggested that the bursal atrophy by treatment of exogenous glucocorticoid is associated with apoptosis, and that the immature lymphocytes in the medulla of follicle are more sensitive to glucocorticoid than the mature one in the cortex.

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The localizations of calcium-adenosine triphosphatase (Ca²⁺ -ATPase) and carbonic anhydrase II (CAII) in the shell gland of the hen oviduct were examined by immunohistochemical technique.
Immunoreactions showing Ca²⁺ -ATPase localization were observed strongly in the luminal surface of the tubular gland cells and in the excretory duct of the tubular gland, but not in the epithelial cells. On the other hand, Immunoreactions showing CAII localization were observed strongly in the cytoplasm of epithelial cells and moderately in the cytoplasm of tubular gland cells. In the shell gland, these immunoreactions showing Ca²⁺ -ATPase and CAII localization were not different at between 3 hours and 12 hours after oviposition.
These results suggest that Ca²⁺ is secreted by active transport of Ca²⁺ -ATPase into the shell gland lumen from the tubular gland and HCO₃^- is produced and secreted in the surface epithelium rather than in the tubular gland.

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It is considered that trimming feathers off abdominal and crural tracts of a hen makes uncomfortable circumstances for parasitizing mites. Two experiments of trimming feather off pterylae of hens were conducted to study of parasitism of mites. Hens used in the two experiments were kept in individual cages in a laying house. The hens were surrounded with hens being not used in the experiments. As the surrounding hens were infested with mites, the hens used in the experiments had a chance to be infested with the mites from the surrounding hens.
Laying hens (193 days old) were infested with mites heavily (1, 001-10, 000 mites/hen) were used in Expt. 1. The parasitism of the mites was observed neither until 6 weeks after trimming feathers off abdominal tract nor until 7 weeks after trimming feathers off abdominal and crural trccts. A number of mites parasitized hen two trimmed groups in Expt.1 were smaller than that of hen non-trimmed (control) group. The hens of the control group were parasitized heavily with mites as the same level at the start of the experiment.
In Expt. 2, 119 days of age hens were used. They were no infestation with mites. After trimming of feathers on abdominal tract, they were kept in the laying house. Infestation with mites were observed at 5 weeks after housing in trimmed hen group while 4 weeks in control group. A number of the mites parasitized hens of trimmed group were less than 10 per hen and hens of control were over 1000 per hen. Parasitism was observed in 28.2% of hens of the trimmed and 100% of hen of control group, respectively.
Hematocrit value of the hens of feather trimmed two groups was increased significantly in Expt. 1 and was not decreased in Expt. 2, comparing with the values at the begining of each experiment. Egg production of two trimmed groups also increased significantly comparing with production at the experiment started in Expt. 1. No increase of egg production was observed in control group. In Expt. 2, egg production of trimmed group was also higher than that of control group. Egg Production of the hens of trimmed groups was higher than that of control groups in Expts.1 and 2, respectively.
Though trimming feathers off abdominal and/or crural tracts of the hen is not to eradicate and prevent parasitism of the mites completely, it is clarified to be useful in practice.

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The present study was conducted to investigate the effects of 2, 2' -azobis (amidinopropane) dihydrochloride (AAPH), a radical initiator, and L-ascorbic acid-2-phosphate magnesium (APM) on growth performance and ascorbic acid concentrations in Single Comb White Leghorn male chicks. Body weight gain, food intake and food efficiency (body weight gain/food intake) of chicks administered with AAPH (5mg/100g body weight/day) for 14 days were significantly decreased compared with control values. However, the supplementation with APM reduced the severity of such adverse effects induced by the administration of AAPH. In chicks administered with AAPH, plasma ascorbic acid was significantly depressed, and the concentrations of plasma and liver thiobarbituric acid reactive substances (TBARS) were significantly increased. The increased TBARS concentrations in plasma and liver were restored by dietary APM supplementation.
Based on the results presented, it was suggested that the chicks given AAPH could serve as an model animal of radical injury, and that APM supplementation is effective for inhibition of oxidative stress by peroxyl radical generated from AAPH.

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Most of broiler houses in Japan adopted the floor feeding system and are concentrated in some areas. These houses are rather difficult to reconstruct into the house to have a few deck flooring system. The author has tried to reuse the broiler house as a full automated broiler house.
Feeding and water supply have been already full automated. Poultry farmers have to go into the house only to take out the dead birds from the house. If dead birds are automatically taken out from the poultry house, we can have a full automated broiler house.
The new cage flooring system having net belt (HOSOYA, 1996) was installed above 80 cm from the concrete floor, and the belt was moved very slowly or imtermittently. This system was tested whether or not successfully work to take out the dead bird. This system has no chance to take pathogen into the house with man, and it reduces dramatically the labour cost by the automation. And it allows manure to pass through and away from the birds, and it offers healthy air condition by automatically eliminating manure from the house. And this system reduces the cost of medication and offers very good remodelling of the old floor feeding poultry house. Speed rate of moving the net belt and pause time of intermittent moving are also discussed.

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