It is widely recognized that eggs are more than a source of dietary nutrients, and extensive studies identifying and characterizing the biologically active components of eggs have been carried out. Numerous biological activities have now been associated with egg components, including antibacterial and antiviral activity, immunomodulatory activity, and anti-cancer activity, indicating the importance of eggs and egg components in human health, and disease prevention and treatment. The potential of some of these biologically active components has already been realized, including egg white lysozyme and avidin, and yolk IgY and lecithin, which are currently produced on an industrial scale, and have been applied for the prevention and treatment of various medical conditions. The information presented here serves to demonstrate the significant potential of biologically active egg components, for medical, nutraceutical, and food-fortification applications.

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Estrogenic compounds must bind to estrogen receptors (ER) and modulate estrogen-sensitive gene expression. However, various in vivo and in vitro assays have established that xenoestrogens and phytoestrogens are rather weak estrogens, with a 5,000- to 10,000-fold lower binding affinity to ER than estradiol-17β (E₂). The purpose of this study was to determine the binding affinity of various estrogen-like chemicals to bacterially expressed quail ERα. The first-strand cDNA was synthesized from total RNA isolated from mature female quail liver with oligo-dT primed reverse transcription. The cDNA included the hinge region, the ligand-binding domain, and the C-terminal domain of quail ERα. It was amplified by PCR, and the PCR product was ligated into GST fusion protein expression vector, and transfected to the E. coli DH5α strain. A binding assay using the supernatant of the cell lysate was performed by incubation with [³H] E₂ and increasing concentrations of competitor at 4°C for 18h. Unbound steroids were removed by the addition of dextran-coated charcoal, followed by centrifugation for 15min. The radioactivity of the supernatant was determined with a liquid scintillation counter. Quail ERα expressed bacterially showed binding affinity to E2 with a dissociation constant of 1.74±0.34 X10^-10M. The competition studies indicated that the relative binding affinities for the synthetic estrogens, diethylstilbestrol and ethynylestradiol, are very high, but that of the xenoestrogens, bisphenol A and nonylphenol, are very low. The phytoestrogens, coumestrol and genistein, can compete with E2 with a significant binding affinity.

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Raw, extruded and roasted rice bran was treated with 0, 125 and 250ppm of antioxidant and stored for period of 12 months. Four trials were conducted, after storage of processed rice bran for 0, 4, 8 and 12 months. Rice bran was given to 1080 broiler chicks in each trial at levels of 0, 100, 200 and 300g/kg as replacement of maize for 6 weeks. Significant decreases in feed consumption, weight gain and feed conversion efficiency were observed when rice bran was given after storage for 4, 8 and 12 months. Better performance was observed when extruded and roasted rice bran stored for 4 months was given to chicks instead of raw bran, while extruded rice bran gave significantly better performance even after storage for 8 and 12 months. No difference was observed between raw and roasted rice bran stored for more than 4 months. Increasing dietary levels of stored rice bran negatively affected the performance of broiler chicks. No difference in performance was observed except for decreases in liver and heart weight compared to control when rice bran stored after addition of antioxidant was given to broiler chicks. Increases in mortality, liver and heart weight were observed when rice bran was given to broilers after storage for 4, 8 and 12 months. Pancreas weight was increased after storage of rice bran for 4 months but there was no difference after storage for 8 and 12 months. Mortality, liver and heart weights of broilers were less with extruded rice bran than with raw and roasted bran. Pancreas weight of chicks was higher with raw rice bran than with extruded and roasted bran. Increasing levels of stored rice bran in chick diets increased mortality and organ weights. Use of stored rice bran in diets of chicks resulted in negative effects on growth, performance, livability and organ weights. However these effects can be avoided by extrusion cooking and roasting. Increasing storage period decreased the nutritional value of rice bran even though it was stabilized by different techniques as shown by decreased performance of chicks. Extrusion cooking is the treatment of choice to stabilize the rice bran followed by roasting, while treatment by antioxidant was only effective to decrease the liver and heart weights of chicks.

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To assess the effect of supplying garlic powder (GAR) in the diet on blood serum and egg yolk cholesterol, maize-soybean diets supplemented with 0 (NC), 0.5 (GAR_0.5), 1 (GAR₁),1.5% (GAR_1.5) as well as Tylosin (PC), were given to 200 hens as a completely randomized experiment throughout a 10 weeks production period. Blood samples for serum cholesterol determination were collected from wing vein of individual hen with two weeks intervals, and egg were collected once a week and subjected to cholesterol assay. Supplementation of diets with garlic powder and Tylosin had significant (p<0.01) effects both on serum and egg yolk cholesterol. The lowest serum cholesterl was obtained with GAR₁, while the NC gave the highest level of cholesterol. A similar trend was observed with yolk cholesterol, in which GAR₁ and NC were the treatments with the lowest and highest cholesterol. The results showed that inclusion of garlic powder significantly (p<0.01) decreased yolk weight, though there were no differences between the different level of the garlic powder. The correlation between yolk and serum cholesterol was negative and low (r=-0.09, p<0.05). In conclusion the results of this study clearly demonstrated that, there is, considerable advantages in using garlic powder rather than chemical reagents in hen rations and there would be even greater advantage both in results and in cost for either poultry industry and consumers, if garlic powder fed to the hens.

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The aim of this study was to develop a method to test the anti-androgenic effects of chemicals in birds. Male Japanese quail were castrated to lead the regression of cloacal protrusion, and they were treated with testosterone or flutamide, an anti-androgenic chemical, after 3 weeks of castration. Then changes in the size of cloacal protrusion area were measured. The cloacal protrusion area increased until Day 14 in birds implanted with silastic tube containing testosterone. In testosterone-stimulated birds, the growth of cloacal protrusion was significantly suppressed by injection with a dose of 10,000μg/100g BW of flutamide. However, significant suppressive effects of flutamide were not observed with doses lower than 10,000μg/100g BW. The size of cloacal protrusion reached the maximum by Day 8 followed by decreasing from Day 13 in the birds implanted with silastic plate containing 1mg testosterone. The growth of cloacal protrusion was significantly suppressed by daily i.p. injection with 10,000μg flutamide. These results suggest that the cloacal protrusion of Japanese quail is a useful marker to test the anti-androgenic effects of chemicals in avian species.

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The aim of this study was to examine whether apoptosis of oocytes occurs and their frequency changes during the ovarian development of embryo and post-hatched chicks of Japanese quail. The ovaries of embryos and chicks were processed for paraffin sections and stained by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. The TUNEL positive cells were observed in both cortex and medulla of Day 14 embryo and day-old chicks, and there were some TUNEL positive oocyte-like cells in the cortex of day-old chicks. In the 7-day-old chicks many of the oocytes, which grew in size and contained germinal vesicle, were surrounded by follicular wall, and 5.8% oocytes were TUNEL-positive. In 14- to 35-day-old chicks, TUNEL-positive oocytes were negligible and only a few cells in the cortical tissue were stained positive for TUNEL reaction. These results suggest that apoptosis of oocytes occurs at pre- and post-hatching phase, and becomes negligible by Day 14 of post hatching, which probably play a role in eliminating the abnormal oocytes to ensure the quality of oocytes.

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This study was carried out to examine which of intravenous glucose or acetate would be rapidly oxidized to CO₂ in growing chickens fed a semi-purified diet.

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Whole mitochondrial DNA of the Silkie fowl (Gallus gallus var. domesticus) was sequenced in order to elucidate the genetic position of the Silkie fowl in its related species based on mitochondrial DNA sequence. The length of Silkie mitochondrial DNA was found to be 16,784 base pairs. The similarity between Silkie and White Leghorn was found to be 99.77% (39 nucleotide differences in 16,784 base pairs). Since the sequences of NADH dehydrogenase subunit 2 and cytochrome b genes have been reported in six species [Japanese quail : Coturnix japonica, Ring-neck pheasant : Phasianus colchicus, Grey partridge : Perdix perdix, Chinese bamboo partridge : Bambusicola thoracia, Chicken (White Leghorn) : Gallus gallus var. domesticus, and Redhead : Aythya americana], nucleotide sequences of these two genes were used for a phylogenetic analysis of Silkie against these six species using neighbor joining and maximum likelihood methods. The Silkie and White Leghorn are in the same phylogenetic cluster with a bootstrap value of 1000/1000.

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