• The Korean Journal of Malacology
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• v.19 no.2
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• pp.111-115
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• 2003

Morphological aspects of the eggs and egg capsules of the neptune whelk, Neptunea constricta (Dall, 1907) (Mollusca: Gastropoda: Buccinidae) are described and illustrated with capsular dimension and enumerations of eggs and egg capsules based on the specimens collected from continental shelf of East Sea, Korea.

• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.157-170
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• 2002

This experiment was conducted to investigate the change of egg qualify by the height of thick albumen of egg, storage temperature and storage period. The albumen index and Haugh unit were measured and compared among five different storage periods(0, 2, 4, 6, and 10 days), four different storage temperatures($15^{\circ}C$ , $20^{\circ}C$ , $25^{\circ}C$ and $30^{\circ}C$ ), and five different Parts(0, 3, 6, 9, and 12 mm) aparted from egg yolk. The albumen index and Haugh unit were as follows: the albumen index of eggs was significantly(P<0.01) different by the storage temperature and by the measuring position of thick albumen of eggs. It means that the albumen index can be differed by the measuring position of thick albumen even if eggs have a same qualify. For measuring egg qualify in this country, it should be announced that which Parts in thick albumen of eggs are measured. The albumen index of fresh eggs was 0.16. However, the index when measured at 3 hour after oviposition was lower than 0.16. Therefore, it indicates that the criterion of 0.06 lower than 0.16 is required to set for considering practical point during the marketing periods of eggs. When the criterion of albumen index puts 0.06, it is as 100%. Therefore, eggs can be kept the same quality for 6, 4 and 2 days when eggs were stored at $15^{\circ}C$ , $20^{\circ}C$ and 25 ~$30^{\circ}C$ , respectively. When the criterion of Haugh unit score puts 79 as 100%, the eggs can be maintained the quality for 6, 4, and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. When the criterion of Haugh unit 55 as 100%, the eggs can be maintained the same quality for 10, 8 and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. From the experimental results, it can be considered that calculathing egg quality by the height of thick albumin of eggs which was measured at the attachment Parts of thick albumin layer and yolk of eggs was most reasonable and suitable when considering the marketing periods of eggs.

• Journal of Photoscience
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• v.9 no.2
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• pp.261-263
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• 2002

The presence of retinals (retinal and 3,4-didehydroretinal) has been known in the eggs of wide range of oviparous vertebrates, but the biological significance of the egg retinals has yet to be clarified. We here show that retinals are the major components of retinoids in the eggs of all species of chordate animals we examined. The egg retinals were commonly bound to egg yolk proteins, the storage proteins, via a Schiff base linkage. The Schiff base linkage, which protects the reactive aldehyde group, would negate the toxicity of aldehyde, and enable to accumulate much amount of retinals. The retinals in chordate eggs are considered to be the precursor of functional retinoids, such as photoreceptive pigment chromophores and retinoic acid, during development. The results of the present research strongly suggest that retinals in the eggs of oviparous chordates are the common and essential mode of retinoid storage.

• The Korean Journal of Ecology
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• v.28 no.4
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• pp.193-198
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• 2005

This study investigated the characteristics of the eggs and yolk sac larvae of Korean striped bitterling, Acheilognathus yamatsutae, spawned and grown In mussels. The number of eggs in the ovary was small ($358{\pm}108$ SD). The eggs were oval and large, and the formation of the perivitelline space was narrow. The eggs were hatched at only 41 hours after fertilization but the hatched larvae were underdeveloped. The development of yolk projection and minute tubercles on the skin surface was notable, along with the vividly moving tail in the hatched larvae. The yolk projection and minute tubercles were disappeared upon enhancement of the motor ability of the larvae was enhanced. The formation of eyes and body pigments of the larvae was relatively delayed in comparison with that of other cyprinid larvae. After completely consuming the yolks the larvae escaped from the mussel for free swimming and exogenous feeding.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.201-206
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• 2008

This study was conducted to determine clutch size and habitat usage of Kentish plovers (Charadrius alexandrinus) breeding on Sinja-do lslet in the Nakdong Estuary from 22 April to 12 July in 1995 and from 21 April to 20 June in 1996. The Kentish plover preferred grasslands and damp sands to dry dunes as nesting sites. The difference in hatching success among these microhabitats was attributed to high tides, which washed away many nests on damp sands, and strong winds, which frequently shifted the sand to bury eggs on dry dunes. The main mortality factor in grasslands was predation by magpies Pica pica. Each clutch contained one to four eggs, with a mode of three eggs. Hatching success was highest in two-egg clutches and lowest in one- and four-egg clutches. The mean interval for egg laying was 1.8 days between the first and second eggs and 2.1 days between the second and third eggs. The average incubation period was about 24.2 days.

• Journal of Life Science
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• v.6 no.1
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• pp.34-39
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• 1996

The biopolymer membrane could be formed using marine polysaccharides. Chiotsan and alginate were used for the formation of capsule membrane to mimic the fish eggs such as flying fish eggs and salmon eggs. The size of capsules ranging 1 to 5mm was prepared and the mechanical tests were performed to determine the mechanical similarities to natural fish eggs. The similar mechanical pattern between the synthetic capsules and natural eggs could be found. The controlling parameters for the strength of capsules were pH of the chitosan solution. This encapsulation technique can be broadly applied to medical, engineering as well as food areas.

• Korean Journal of Animal Reproduction
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• v.9 no.2
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• pp.153-157
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• 1985

Ejaculated and epidiymal goat spermatozoa were preserved for 0, 6, 12 adn 18 h, and 0 and 18 h in a semi-aerobic condition at 20-$25^{\circ}C$, and preincubated for 5-6 h in a CO2 incubator in m-KRB solution. Then they were preincubated at different concentrations (3-5, 25-48 and 105-190$\times$107/ml), and ability of penetration into zona-free hamster eggs in vitro was examined. When ejaculated spermatozoa were preincubated in m-KRB solution after presservation for 12 and 18 h, 12 and 29% of zona-free eggs were penetrated, and only 4% of eggs were penetrated by epididymal spermatozoa which were preincubated after preservation for 18 h. When spermatozoa were preincubated at a low concentration, the penetration rates were very low. But when the sperm concentration during preincubation was 25-48 and 105-190$\times$107/ml, the penetration rates increased to about 30%.

• Ocean and Polar Research
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• v.24 no.4
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• pp.443-448
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• 2002

A study on the ichthyoplankton assemblage was conducted around Dokdo in the East Sea in September 1999 and May 2000. Sixteen species of fish larvae including eggs were collected during the surveys. Anchovy (Engraulis japonicus) eggs and larvae were comprised of 2.0% and 94.5% of total samples in number, respectively. Muller's pearlside (Maurolicus muelleri) eggs and larvae were comprised of 95.0% and 3.2%, respectively. The other species mostly composed of warm water species were less than 2% of total samples in number. The number of species and abundance of the fish lawae and eggs were higher in September than in May. Although there were limited data on the ichthyoplankton around Dokdo in summer and winter, this study area seems to be used for the spawning or nursery ground of fishes.

• Journal of Sericultural and Entomological Science
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• v.6
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• pp.53-56
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• 1966

1. On the contrary to the general insect size, male is larger than female. 2. The possible number of eggs, the maximum number of eggs per a morh is average 225 eggs. 3. The periods of the eggs laid is around 3 days. 4. The growth period of larva is about 14 days. 5. The period from the unifection to death is an indirect proportion to number of the eggs. 6. The period from the pupation to flying is about 14 days, depending upon the temperature.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.58-60
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• 2003

The author has observed a reeves turttle (Chinemys reevesii) obtained from a market on Jeonju city, Korea. The turttle laid 5 eggs during the period from 31st Aug. to 5th Sep., 2003. The range of egg sizes was 3.5-3.9${\times}$1.9-2.4 cm and that of egg weights, 7.2-10.9 g. It seems to be difficult to distinguish the reeves tuttle eggs from the red-eard tuttle (Pseudemys consina consina) eggs because they are so similar each other in size and shape. He could not hatch out the reeves tuttle eggs.