• Asian-Australasian Journal of Animal Sciences
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• v.25 no.7
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• pp.1009-1014
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• 2012

Environmental stress boosts the levels of stress hormones and accelerates energy expenditure which subsequently imbalance the body's homeostasis. L-ascorbic acid (L-AA) has been recognized to mitigate the negative impact of environmental stress on production performances in birds. The present investigation was carried out to elucidate the effect of different dietary levels of L-AA on production performance, egg quality traits and fertility in Japanese quail at low ambient temperature. Sixty matured females (15 wks) were equally divided into three groups (20/group) based on the different dietary levels of L-AA (0, 250 and 500 ppm) and coupled with an equal number of males (1:1) obtained from the same hatch. They were managed in uniform husbandry conditions without restriction of feed and water at 14 h photo-schedule. Except for feed efficiency, body weight change, feed consumption and hen-day egg production were recorded highest in 500 ppm L-AA supplemented groups. Among the all egg quality traits studied, only specific gravity, shell weight and thickness differed significantly (p<0.05) in the present study. Fertility was improved significantly ($p{\leq}0.01$) to a dose dependent manner of L-AA. The findings of the present study concluded that dietary L-AA can be a caring management practice at least in part to alleviate the adverse effect of cold induced stress on production performance in Japanese quail.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.243-247
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• 2007

We investigated the reproductive behavior of Octopus minor, order Octopoda, class Cephalopoda under laboratory conditions. Each mature female octopus was kept in an aquarium with a plastic tube for shelter, and one mature male was introduced for the purpose of copulation. Before spawning, the female coated the roof of the shelter with a light-green material, upon which it then fixed its eggs one by one. This spawning behavior lasted 1 to 3 days. Fertilized females spawned 54 eggs on average, ranging from 21 to 112 eggs at 72 to 98 days after copulation. The attached eggs were 18.1-19.0 mm in length, 5.0-6.1 mm in width, and 0.30-0.38 g in weight. The mother octopods did not feed; they attended to the eggs by using their arms to rub the egg surfaces and used their funnel to blow sediments off of the eggs. At water temperatures of $20.9-21.5^{\circ}C$, the fertilized eggs hatched within 73 to 90 days after being spawned. The effective cumulative water temperature was $1,569-1,892^{\circ}C$. At the end of incubation, the body weight of the mother octopods was reduced to approximately 56% of the initial weight, and most mother octopods died soon after the young hatched.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.104-109
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• 2013

The spawning characteristics of Hexagrammos agrammus and Hexagrammos otakii was directly observed in coastal regions of the Yellow Sea and South Sea during the spawning seasons using scuba diving. The territorial male H. agrammus showed different body size, nuptial coloration and nest location compared to those of H. otakii, even though both species caring egg masses were found at the almost same depths. In the West sea, a relatively small guardian H. agrammus male protects 1-2 egg masses laid on a clump of red algae within his territory. The territorial males in red nuptial coloration and their egg masses were well camouflaged in their surroundings. Contrary to H. agammus, a guardian H. otakii male in yellowish nuptial coloration protects 4-8 egg masses in a nest. In addition, their nests were located on the relatively open environments such as discarded fishing nets, rock crevices and a clump of algae. The results of present study shows that even though both of two species belonged to Hexagrammidae, they have different strategies for spawning and protecting their egg masses.