• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.195-200
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• 2010

A large volume of hatching jar was tested whether it is an effective to hatch fertilized eggs of Pacific cod. The volume of hatching jar did not show any significant differences in survival of the fertilized eggs; 48.3% for the jar of 15 L and 50.4% for that of 42 L. Survival rate of the fertilized eggs in a large volume of hatching jar ranged from 40.0 to 71.2%, which was higher than those of conventional small circular tank. A higher survival could be achieved even though stocking density of fertilized eggs was as high as 5,000 mL/jar. Consequently, the tested hatching jar allowed for incubation of a greater number of eggs with higher survival rate in a much smaller space. In addition, it reduces costs and manpower, and requires a relatively small amount of water per individual unit (6,700 mL/min), and provides a way to incubate multiple rearing groups in a quarantine environment.

• Journal of Aquaculture
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• v.12 no.1
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• pp.25-30
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• 1999

This study was carried out to produce the seedling of the larvae and juveniles of pale chup, Zacco platypus (Cyprinidae) in terms of artificial hatching, feeding behavior and growth rates. The total lengths of the newly hatched larvae were 7.6~8.2mm (mean: 7.97mm). The hatched larvae rose to the surface 3 days after hatching. The larvae were fed Daphnia, rotifer, Artemia and powdered feed. Hatching experiments were conducted in jar incubators under the different water temperature conditions, $20~32^{\circ}C$. The highest hatching rate was at $26^{\circ}C$ after 47 hours. Jar incubators was the highest hatching rate (89%), and cage and Californian incubators were useful and relatively high hatching rates (>89%). The size of the larvae 50 days after hatching were 30.0mm (25.6~32.0mm). As the water temperatures was increased, the growth rate of the larvae was also increased. Especially, the growth rates were favorable over $26^{\circ}C$, but survival was the worst at $32^{\circ}C$. This species was quick to accept assorted feed after hatching. The assorted feeds for flounder and rockfish better than that of carp in reference to growth rate.

• Journal of Korean Elementary Science Education
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• v.35 no.2
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• pp.166-180
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• 2016

This paper examines the effects on academic achievement, scientific process skills and affective domain for elementary students learning the 'Chicken life cycle' through traditional science class versus a smart media based STEAM approach. Students designed and built a hatching jar and created a smart media content for chickens using time-lapse technology. This STEAM program was developed to improve their scientific concepts of animals over nine periods of classes using integrated education methods. The experimental study took place in the third grade of public schools in a province, with the STEAM approach applied in 2 classes (44 students) and the traditional discipline approach implemented in 2 classes (46 students). The STEAM education significantly influenced the improvement of academic achievements, basic scientific process skills and affective domain. The results suggest that this STEAM approach for teaching scientific concepts of animal life cycles has the performance in terms of knowledge, skills and affect gain achievements in elementary school students' learning when compared to a traditional approach. Moreover, the smart media based STEAM program is helpful to lead students to engage in integrated problem-solving designs and learning science and technology.