• Korean Journal of Poultry Science
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• v.24 no.4
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• pp.199-206
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• 1997

In this experiment, three kinds of autoclaved poultry by-product meals, P1 (head+feet+viscera), P2(P1+blood), and P3(P2+feathers), mixed as to the yielding ratios, and three kinds of autoclaved hatchery by-products meals, H1 (male d-old chicks of egg strain), H2(dead embryos ＆ infertile eggs), and H3(H1+H2, 2:1) were formulated into the layer diets each at 5％ level, respectively, and compared with the control diets(C) containing fishmeal on laying performances and egg qualifies. The egg production, average egg weight, feed intake and feed conversion were not significantly affected by the poultry or hatchery by-product meals. The egg shell qualities, such as the egg specific gravity, egg breaking strength and shell thickness, were not different among treatments. The egg yolk colour was improved by the feeding of hatchery by-products meals (P<0.05). In conclusion, pultry and hatchery by-product meals could be used in layer diets without any adverse effects on laying performances to substitute for fishmeal at about 5％ level.

• Korean Journal of Poultry Science
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• v.21 no.2
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• pp.139-150
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• 1994

Egg cholesterol has been a hot issue in respect of it's effect on health and diseases in human. There is a general recognition that the cholesterol from eggs is similar to that from the other dietary sources in its biochemical functions. Many evidences show that egg yolk increased plasma cholesterol levels at an average rate of 2.3 mg /100 rnL plasma for every 100 mg cholesterol consumed. The elevation of plasma cholesterol could, however, be altered by various dietary factors such as ratios of polyunsaturated fatty acids and saturated fatty acids. Blood cholesterol levels of Korean adults have been raised up to, on the average, 193 and 187 mg /100 mL plasma for men and women, respectively, from 167/5 mg /100 mL in 1980. Furthermore, proportion of hypercholesterolemics(> 210 mg /dL) has been increased up to 23% of the population. These changes in blood cholesterol levels are attributed to the changes of dietary patterns, suggesting the arguement that Koreans are insensitive to changes of blood cholesterol is not right. Egg cholesterol levels have never been successfully reduced to any significant levels even with tremendous amounts of efforts made during last decades. The alternative and the best way to control blood cholesterol level originating from egg consumption appeares to enrich egg fat with omega-3 series fatty acids. Ingestion of the fatty acid group has specific functions to reduce hypertension and prevent various types of cancer as well as to reduce blood cholesterol. Another way to reduce egg cholesterol directly is to produce smaller egg yolk without reducing whole egg size since cholesterol is located only in the yolk. It is important to keep faith with consumers by providing correct informations on eggs, meanwhile efforts need to focus on to improve the quality of eggs as one of the best protein food items.

• Ocean and Polar Research
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• v.25 no.3
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• pp.249-256
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• 2003

An immunological method was developed in this study to quantify reproductive output of the female butter clam, Saxidomus purpuratus. A clam egg-specific polyclonal antibody was developed using the purified butter clam egg as an antigen. An indirect Enzyme-Linked Immunosorbent Assay (ELISA) was used in quantitative measurement of the eggs. Size of the butter clam eggs ranged from $70.81{\pm}7.52{\mu}m$ in histology or $88.56{\pm}11.31{\mu}m$ in intact eggs. The predominant egg constituent was protein (37.44%), followed by lipids (11.40%) and carbohydrates (9.68%). The SDS-PAGE showed that the egg proteins are composed of several peptides of molecular weights consisting of 247, 200, 99, 91, 54 and 47 kDa. ELISA indicated that the clams collected from Geoje Island in May 2002 produced 8.2 to 26.8% of their body weight as eggs or 9,307,309 to 31,156,333 with a mean of 16,931,893 eggs per individual clam. The results of this study thus suggest that indirect ELISA using rabbit anti-clam egg IgG as a primary antibody is a rapid, affordable and sensitive method to assess reproductive output of 5. purpuratus and possibly other bivalves using a small amount of eggs.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.39-44
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• 1997

Two experiments were carried out to determine the effects of pelleting layer diets on the laying perforrnance and nutrients utilizability, using either 50-wk-old(Experiment 1) or 80-wk-old (Experiment 2) layers. There was no effect of pelleting layer diets on hen-day egg production and average egg weight but decreased (P<0.05) feed conversion ratio(intake /egg weight) in both experiments. Although both egg specific gravity and eggshell thickness were not influenced by pelleting eggshell breaking strength was improved(P<0.05) only in Experiment 1. Utilizability of dietary fat was improved(P<0.05) by pelleting layer diets with no difference in other nutrients utilizability. There was no difference in the passage rate of mash and pelleted layer diets.

• Development and Reproduction
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• v.15 no.3
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• pp.197-204
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• 2011

Egg activation is a crucial step that initiates embryo development upon breaking the meiotic arrest. In mammalian, egg activation is accomplished by fusion with sperm, which induces the repeated intracellular $Ca^{2+}$- increases ($[Ca^{2+}]_i$ oscillation). Researches in mammals support the view of the $[Ca^{2+}]_i$ oscillation and egg activation is triggered by a protein factor from sperm that causes $[Ca^{2+}]_i$ release from endoplasmic reticulum, intracellular $[Ca^{2+}]_i$ store, by persistently activation of phosphoinositide pathway. It represents that the sperm factor generates production of inositol trisphosphate ($IP_3$). Recently a sperm specific form of phospholipase C zeta, referred to as PLCZ was identified. In this paper, we confer the evidence that PLCZ represent the sperm factor that induces $[Ca^{2+}]_i$ oscillation and egg activation and discuss the correlation of PLCZ and infertility.

• Journal of Embryo Transfer
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• v.16 no.1
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• pp.61-68
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• 2001

Sperm competent for fertilization can become capacitated, bind to the zona pellucida (ZP) of an egg in a specific manner, and complete acrosomal exocytosis. Failure to carry out these functions results in infertility. Although the interactions between the ZP and the plasma mem-brane overlying the sperm acrosome have been considered important for sperm-egg recognition and signalling, recent results have prompted a reassessment of current paradigms concerning these interactions. In this review, we're going to discuss about the roles of the acrosomal matrix, the particulate component of the acrosomal contents, in fertilization. The general hypothesis is that acrosomal exocytosis leads to the exposure of acrosomal matrix proteins that become de-facto extracellular matrix (ECM) on the surface of the sperm head, and that the dynamic interactions of this newly-exposed sperm ECM with the egg ECM (the ZP) govern sperm-egg recognition and sperm penetration of the ZP Informations from these experiments may provide new ways to address the poor ZP binding of sperm from some human infertility patients and may offer new avenues for contraception through the disruption of purposeful sperm-ZP binding.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.157-164
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• 1990

The surface patterns and the structures of transverse section of the egg-shell of the sikmoth, Bombyx mandarina, have been described by scanning electron microscope. Three spatially differentiated cross section, called lamellar, conic pillar and cover layers, are found on the mature eg-shell. Silkmoth chorion proteins were detected more than 80 components from a single chorion by two-dimensional electrophoresis. Major protein components of the egg-shell have bee identified on the basis of their isoelectric points and molecular weights, pH 4-6 and 6-30 kd. Several protein components are found entirely or predominantly in th cover layers.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.107-114
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• 2012

The present study evaluated the potential use of immunoglobulin prepared from egg yolk of chickens immunized with Escherichia coli K88 (IgY-Ec) in the control of E. coli K88 infection in RAW 264.7 murine macrophage. The binding activity of IgY-Ec against E. coli K88 surface protein was more specific and increased than control IgY. In infection assay of E. coli in macrophage, the specific IgY-Ec to E. coli K88 remarkably inhibited the phagocytic activity comparing to nonspecific IgY (p<0.001). In adherence assay, bacterial adhesion on macrophage cells was definitely reduced by preincubation of IgY-Ec compared with nonspecific IgY (p<0.05). These findings suggested that IgY-Ec have the protective effects against pathogens and IgY-based diets may have potential benefits for preventing or treating various infections in domestic animals.

• The Korean Journal of Zoology
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• v.30 no.1
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• pp.10-28
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• 1987

Changes of protein synthesis in the isolated egg chambers were studied during oogenesis of Drosophila melanogaster. Protein synthesis did not change much in quantity except that the activity was slightly enhanced at the stages 11 and 12, when new structures such as vitelline membranes and yolk granules were made, but considerably changed in quality during oogenesis. Protein synthesis was believed to occur mainly in the follicle cells, and a number of stage-specific proteins were found to differ at various stages. The observations suggest that proteins synthesized in the cells within chambers as well as those from the outside of the chambers might be directly required for the growth and maturation of oocytes in Drosophila.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.524-530
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• 2006

Two protease inhibitors of 67 and 18 kDa, respectively, were purified from the eggs of glass fish, Liparis tanakai, by affinity chromatography and electro-elution method. The high molecular weight (HMW) protein was purified with a specific inhibitory activity, yield, and purity of 18.46 U/mg, 0.07%, and 131.86 fold, respectively, and was further characterized: Optimal temperature and pH for inhibitory activity of the HMW glassfish egg protease inhibitor were $40^{\circ}C$ and pH 6, respectively, and it was stable between $5^{\circ}C\;and\;50^{\circ}C$ in the pH range of 5-6 with maximal stability at pH 6. It was shown to be a competitive inhibitor against papain with an inhibition constant $(K_i)$ of 97.02 nM. Moreover, the 67 kDa protein inhibited cathepsin, a cysteine protease, more effectively than did an egg-white protease inhibitor. The HMW glassfish egg protease inhibitor was classified as a member of the family III (kininogen).