Egg shell quality and egg internal quality are of major importance to the egg industry worldwide. This review covers the formation of the hen’s egg and ways of measuring egg shell quality and egg internal quality. Egg shell quality may be measured as egg size, egg specific gravity, shell colour, shell breaking strength, shell deformation (destructive or non-destructive), shell weight, percentage shell, shell thickness, and shell ultrastructure. New methods emerge from time to time. Egg internal quality is measured as yolk colour, the integrity of the perivitelline membrane, and albumen quality. Factors that affect egg shell quality and egg internal quality are reviewed. The complexity of the process of egg shell formation means that imperfections can arise in a number of places in the oviduct of the hen. Egg shell quality may be affected by the strain and age of hen ; induced moult ; nutritional factors such as calcium, phosphorus, vitamins, water quality, non-starch polysaccharides, enzymes, contamination of feed ; general stress and heat stress ; disease, production system, or addition of proprietary products to the diets. Egg internal quality may be affected by storage ; hen strain and age ; induced moult, nutrition, and disease. An understanding of the range of factors that affect egg shell quality and egg internal quality is essential for the production of eggs of high quality.

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The migratory ability of germ cells collected from gonads at different stages of embryonic development was investigated in the domestic chicken.
In Experiment 1, primordial germ cells (PGCs) were collected from 2.5-day-old embryo. Also gonadal germ cells (GGCs) were collected from 6.5-, 10.5-, 14.5-, 18.5-, and 20.5-day-old embryos. PGCs and GGCs were labeled with the fluorescent dye PKH-26, and 20 fluorescently labeled PGCs or GGCs were injected into the vascular systems of 2-day-old recipient embryos. The total number of fluorescently labeled cells recovered from both the left and right gonads of the recipient embryos was counted 5 days after injection. The proportion of recipient embryos carrying fluorescently labeled cells was 100% when the donor GGCs were collected from 6.5-, and 10.5-day-old embryos. The proportion decreased when the donor GGCs were from embryos incubated for longer than 14.5 days. An inverse relationship was observed between the total number of fluorescently labeled cells in the recipient gonads and the age of the donor embryo.
In Experiment 2, gonadal cell suspensions were prepared from the left gonads of newborn chicks and adult chickens. Gonadal cell suspensions were labeled with the fluorescent dye PKH-26 and injected into the vascular systems of 2-day-old recipient embryos. The proportions of recipient embryos with fluorescently labeled cells in their gonads were 100% (3/3), 100% (3/3), 100% (3/3), and 67% (2/3) when the injected gonadal cell suspension was from male newborn chicks, female newborn chicks, adult roosters, and adult hens, respectively.
These results indicate the presence of migratory germ cells in the gonads of developing embryos until day 20.5 of incubation. Furthermore, these results also suggest the presence of migratory cells even in the sexually matured testes or ovaries.

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A cecostomy technique was developed to quantify urine back flow into the ceca of fed and feed-deprived adult male chickens.
On the two days after surgery, the tubings of cecostomized chickens were flushed with 20 ml of warm saline solution every other day for 10 days. The operated chickens were allowed for 2 more weeks for recovery without such a flush. Excreta were collected daily for the last 3 days of 4-day-fast in the fasted chickens, and for 3 days in the ad libitum-fed chickens from cecal tubings and cloaca by surgical attachment of polyethylene collection vessels to the chickens. Uric acid excretion was significantly more in fed chickens than in feed-deprived birds. Uric acid from the ceca was 7.74% and 5.31% for fed and feed-deprived chickens, respectively. Post-mortem examinations ascertained that the ceca were intact around the Latex tubing.
The results suggest that at least 5% of daily ureteral urine flow could retrograde into the ceca of roosters.

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Major histocompatibility complex class II (MHC-II) molecules play essential roles in the initiation of immune responses against pathogenic agents. Salmonella enteritidis (S. enteritidis) bacteria may contaminate hen eggs during their formation in the ovary. The goal of this study was to determine whether ovarian MHC-II⁺ cells respond to S. enteritidis. Laying hens were intraperitoneally injected with or without PBS (control) or S. enteritidis (5.0×10⁹ bacteria/bird) and examined 12h after inoculation. Cryostat sections of ovarian stroma, small white follicles and preovulatory follicles were double-immunostained sequentially for the localization of MHC-II⁺ cells and S. enteritidis. The MHC-II⁺ cells were localized in the ovarian stroma and the theca layer of the stromal, small white and preovulatory follicles. S. enteritidis was detected in the stroma and the theca layer of all types of follicles 12h after inoculation. The frequency of MHC-II⁺ cells was significantly increased in the ovarian stroma and the theca of all types of follicles by S. enteritidis inoculation (P<0.01) but not by PBS injection. These results suggest that the population of MHC-II⁺ cells in ovarian tissues increases in response to S. enteritidis invasion for defending against them.

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This paper describes the morphology, phagocytic capacity, and response to lipopolysaccharide (LPS) of peritoneal macrophages (Mφ) from Japanese quail, following induction by thioglycollate.
1) Analysis by transmission and scanning electron microscopy : Similar to chicken Mφ, non-activated (4°C) quail Mφ had many gathering processes on the cell surface. Activated (37°C) quail Mφ exhibited a few long, extended pseudopodia. The cell nuclei of both non-activated and activated quail Mφ differed from chicken cell nuclei in that they contained one large and several smaller heterochromatic bodies, which were attached to the nuclear membrane and other quail somatic cells.
2) Phagocytic activity for sheep red blood cells (SRBC) : The phagocytic activity for SRBC of Mφ from non-immunized quail (niMφ) was significantly less than that of Mφ from SRBC-immunized quail (imMφ) (p<0.05). However, the phagocytic activity of niMφ significantly enhanced by treatment of the SRBC with anti-SRBC quail serum (p<0.05). In contrast, the phagocytic activity of imMφ did not change following treatment of the SRBC with anti-serum. These results suggest that the phagocytic activity of quail Mφ for SRBC is enhanced by opsonization, but that levels of the opsonin receptor on the cell surface of Mφ might be decreased by immunization with SRBC.
3) Stimulation with LPS : The activity of LPS-stimulated Mφ (MTT assay) was greatest 0.5 hours after cultivation began. Following LPS stimulation, quail Mφ produced molecules of 44.5kDa and 73.3kDa, probably interleukin-6 (IL-6) and carrier protein complexes.

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Controversy about the efficacy of Alimet as a source of methionine arises from the fact that when it is ingested, it is fundamentally different from methionine. Thus, broiler performance studies comparing efficacy of Alimet and DL-methionine (DL-met) continue to be of interest. This report will cover two studies using Alimet Feed Supplement (an 88% aqueous solution of 2-hydroxy-4-(methylthio)butanoic acid, HMTBA). The objective of the first was to compare Alimet with DL-met as sources of supplemental L-methionine (L-met) for broiler production. The sources were fed on an equal dry-matter basis at a level approximating 85% of that used in commercial practice in the UK, where the study was run. A basal diet was used to confirm sensitivity to methionine source addition. No antibiotics were fed. Results confirmed a significant response to supplemental methionine over the 0-42 day study for gain and feed conversion efficiency with no significant difference between Alimet and DL-met. The objective of the second study was to compare performance of Alimet with DL-met when birds were fed high inclusion levels. In this experiment, conducted at Novus International, performance in a basal diet was compared to five supplemental levels of Alimet or DL-met (0.2, 0.5, 1.0, 1.5 and 2.0%). The first level of supplementation was designed to represent an adequate diet with subsequent levels representing excessive addition. Results confirmed that the performance and feed intake of birds fed DL-met was more negatively affected than those fed Alimet, with differences becoming significant above the 0.5% level. Data presented here confirm full molar equivalency of HMTBA to DL-met in broilers fed commercial diets and illustrate the relatively greater safety of Alimet when fed at higher inclusion levels.

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Genetic coadaptability in two neutral loci (Mpi-I and Es-D) was studied in wild quail population which settled down in Weishan Lake area in China, after that a new statistical model of genetic coadaptability was put forward and examined. Results showed that the model is suitable to test the genetic coadaptability, which exists in two loci, and genetic coadaptablity accounts for more than one third in the population genetic disequilibrium coefficient. Moreover, the population linkage disequilibrium was broken down by this effect. Therefore, genetic coadaptability is one of the key factors to the genetic disequilibrium in the population and reflects important information of evolutionary history. It can be applied to studying population phylogenetic differentiation, genetic structure evaluation and phylogenetic relationship. It is therefore very important and should attract much more attention on studying population genetic constitution.

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A protease present in an enzyme preparation may digest other enzymes and thus reduces the effectiveness of an enzyme preparation to improve digestibility of animal feeds. Thus the effects of enzyme mixtures with or without proteases were tested on the digestibilities of crude protein (CP) and dry matter (DM) in corn soybean mixture (CSBM) in vitro. The effects of cellulase, xylanase, pectinase, hemicellulase, glucanase, phytase, commercial enzyme (Energex) or protease inhibitor on digestibilities were also examined. The cellulase significantly improved CP digestibility measured by the pepsin-pancreatin method. However, protease, phytase, pectinase, xylanase, glucanase, and hemicellulase had no effect on the CP digestibility. On the other hand, CP digestibility was significantly increased by the mixture of all the enzymes used, and its effect was further improved when protease was excluded from the enzyme mixture. When protease inhibitor, leupeptin, was added in the combination of all enzymes, digestibility was further improved. Although Energex had no effect on CP digestibility of CSBM, CP digestibility tended to be improved when protease inhibitor was added. Any of single enzyme and their combination did not have significant effects on DM digestibility of CSBM. In conclusion, the present results strongly suggest that cellulase improves CP digestibility of CSBM whereas protease inhibits the actions of these enzymes. Omitting proteases from commercial enzyme preparations may improve their actions on digestibility.

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The amount of calcium, magnesium and phosphorus in the shell portion (shell with shell membrane) of eggs of guineafowl and chicken at various times during the stay in the uterus was measured by an atomic absorption spectrometry or colorimetric method. All of the minerals were found to increase during the stay in the uterus, but the aspect of the increase differs between the minerals : parabolic in calcium, linear in magnesium, and quadratic in phosphorus, and also differs between the guineafowl and the chicken.

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An experiment was conducted to determine effect of substitution of fish meal with soybean meal on growth performances and excreta moisture contents during immunological stimulation induced by injection of Escherichia coli lipopolysaccharide (LPS) and Sephadex in male broiler chicks. Chicks (a day old) were fed either a diet containing plant ingredient only as a plant diet or a diet replaced a part of soybean meal of the plant diet by fish meal as a fish meal diet through the experimental periods. Both diets were formulated to contain most essential nutrients at the recommended levels of the nutrient requirement of the Feeding Standard for Poultry. Birds fed each diet were intraperitoneally injected with LPS at 500μg /kg BW on 14, 16 and 18 days of age and with Sephadex-G50 at 250mg/kg BW on 15 and 17 days of age to simulate immune function, especially macrophage function. Feeding the diet containing fish meal did not affect growth performances and excreta moisture contents as compared with feeding the plant diet before the immune stimulation. However feeding the fish meal diet improved growth performances, water intake to feed intake ratio and reduced excreta moisture content (P=0.07) during the immune stimulation. Water intake to feed intake ratio was significantly lower in chicks fed the diet containing fish meal than that fed the plant diet, regardless of immune stimulation. Ceruloplasmin concentration in plasma of chicks fed the fish meal diet was lower than that of chicks fed the plant diet after LPS injection. The results suggest that feeding diets containing plant sources only does not necessarily assure the same performance and excreta quality as feeding diet containing animal protein sources during immunological stimulation by injection of LPS and Sephadex in male broiler chicks.

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