• KOREAN POULTRY JOURNAL
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• v.56 no.2
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• pp.137-137
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• 2024

• Journal of Aquaculture
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• v.14 no.3
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• pp.165-171
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• 2001

Tolerance limits of the adult crab were determined by exposing them to different temperatures (5~2$0^{\circ}C$) and salinities(12~32$\textperthousand$). The tolerance limit for high temperature was determined at 14$^{\circ}C$ and 16$^{\circ}C$ for male and female snow crab, respectively and that for salinity was 21 $\textperthousand$ at 5 $^{\circ}C$. Osmolality concentration, Na$^{+}$ and $K^{+}$ ions in the haemolymph of especially, the females was positively related to the salinity changes. Increased water temperature resulted in a marked decreased in ionic and osmolality concentrations near the limit of tolerance in male, however, such a clear pattern was not apparent for the females. The concentration of glucose in the haemolymph was positively related to water temperature but negatively to salinity.ity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.1-5
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• 1997

The $Bi_2Sr_2Ca_{n-1}Cu_nOy$(BSCCO) phase is well known to be a superconductor having a strong anisotropic behavior. It can be seen that it is difficult to control the growth direction. In this study, we try to grow a Bi-Sr-Ca-Cu-O phase crystal by the crystal pulling method with a seed crystal and crucibel rotation. Relatively large crystals of the order of $5{\times}5{\times}5{\textrm}{mm}^3$ dimensions can be obtained. We also discuss the possible crystallization field of the $BiO_{1.5}$-(Sr, Ca)O-CuO ternary phase diagram, and present some results of the characterization and magnetic measurements on the grown crystal.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.1
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• pp.57-68
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• 1982

In order to investigate the effect of dietary protein and energy on growing female and male rats, Sprague-Dawley 90 female rats and 54 male rats of 3 weeks old weighing approximately 70-80g and 65-75g, respectively, were subjected to feeding trials for 8 weeks and then subsquently to metabolic trials for 2 weeks. Three dietary energy levels (3200, 3600, 4000 kcal ME/kg) were employed and each energy level contained three protein levels (15, 25, 35% of 3600 kcal ME/kg) and three fat levels (10, 20, 40% of 3600 kcal ME/kg) by addition of an appropriate amount of carbohydrate and the following results were obtained. The body weight gain of female rats was highest for LPHE ration but that of male rats was highest for LPME ration. The weight gains both of female and male rats were not affected by the level of protein. Food efficiencies both of female and male rats was affected by the level of protein, whereas that of male rats was not. Protein efficiencies of female and male rats were highest at low protein level and tended to decrease as the level of protein increased, but that of female rats was highest at high energy level, while that of male rats was highest at medium energy level. The analysis of the body composition after feeding trials for 8 weeks has shown that the contents of body water and protein were not affected by protein level both in female and male rats. The content of body fat increased remarkably as the protein and energy levels increased in case of female rats, but it was not affected by the protein and energy levels in case of male rats. From the above-mentioned experimental results it may be con eluded that the best formula of diet of growing female rats may be composed of low protein (13%) and high energy levels (4000 kcal/kg) whereas that for male rats may be composed of low protein (13%) and medium energy levels (3600 kcal/kg), since all the efficiencies of food, protein and energy have shown to be best at these levels.

• Korean Journal of Poultry Science
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• v.37 no.1
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• pp.43-49
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• 2010

The effect of sex ratio on behavior and welfare indexes in broiler chickens was investigated. Five variants of the sex ratio (male to female), namely, 100:0 (T1), 75:25 (T2), 50:50 (T3), 25:75 (T4) and 0:100 (T5) were tested in broilers between the ages of 7 to 35 days. It was found that the most common behavior in all sex ratios was resting behavior, ranging over 74.4 % of total behavioral frequency. The ranges of other behavior traits of total behavior traits were as follows: pecking, 5.4 to 23.1 %; standing, 1.8 to 24.8 %, and moving, 0.6 to 11.5 %. The behavioral frequency of resting, pecking, standing and moving were not affected by the sex ratio and between male and female. But the percentage of pecking, resting and moving behavioral frequency was significantly different by the age of birds (P<0.05). Age of birds had no effect on standing behavioral frequency. It seems that gait, food pad and hock burn score were no affect by sex ratio but tend to decreased in female than male. Claw length of 21 and 35 days was not affected by sex ratio and between male and female. The duration of tonic immobility (TI- reaction) was tend to decreased age of 21 than 35 days, and female than male. Both male and female of the study, hock burn score, claw length and TI-reaction were tend to lower in T4 than other treatments. The results suggest that, when male and female broilers are reared together, sex ratio can influence broiler welfare indexes in this study.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.259-263
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• 2006

The objectives of this paper are to estimate home range and core habitat area of raccoon dog living in the rural area of Korea. A radio-telemetry study was carried out on 22 raccoon dog individuals. Among these individuals, 4 raccoon dogs made 2 pairs and they were monogamous and moved together all the year round. Mean home-range size of 9 individuals which were radio-tracked more than 3 months was $0.80km^2$ (100% MCP). The mean home range size of male individuals was $0.98km^2$ (N=5, 100% MCP) and that of female individuals was $0.58km^2$ (N=4, 100% MCP). On the other hand, in case 95% MCP(Mininlum Convex Polygon) was applied, the gap of home-range size between sex distinction was closed to $0.63km^2$ (male) and $0.42km^2$ (female). The home range size of two pairs of which the male and the female were radio-tracked at the same time showed little difference. In case of one pair, the home range size(95% MCP) was $0.28km^2$ (male) and $0.26km^2$ (female) and in case of the other pair, it was $0.36km^2$ each (male and female). Consequently there seems no significant difference in the home-range size between a male and a female racoon dog except the unusual cases such as unpaired individuals or the ones with no fixed territory.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.305-311
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• 2019

Artificial interspecific matings between Matsumuraeses phaseoli and M. falcana (Lepidoptera: Tortricidae) were conducted to know the possibility of hybridization of the two sympatric species. Reciprocal crossings successfully produced F1 hybrids. Most of F2 crosses yielded progenies except all mating trials with females of F1 hybrid obtained from M. phaseoli female. Inbreedings of the F2 hybrids produced F3 progenies. In backcrossings between F1 hybrids and parent lines, all the two mating trials with females of F1 hybrid obtained from M. phaseoli females did not produce any progeny, while other 6 backcrosses produced the next generations. Inbreedings of the backcross lines also produced subsequent progenies. These results indicated that F1 females produced from hybridization between M. phaseoli females and M. falcana males were sterile. Conclusively, it suggested that a partial reproductive isolation at a postzygotic stage can occur between the two sympatric species.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.85-89
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• 2004

Numerical measurements were made for fresh weight, body length and width, head width, and color and length of antenna of Japanese pine sawyer, Monochamus alternatus adults, a primary vector of pine wood nematode, Bursaphelenchus xylophilus in Korea. We measured 563 females and 601 males that emerged out of dead pine logs from 2001 to 2002. General linear model analysis showed that measurements of fresh weight, body length, and body width were significantly higher in females than in males. Head width was not significantly different between sexes. Antennal length of males was significantly longer than that of females. For females and males respectively, average fresh weights were 0.305g and 0.277g, body lengths 20.97mm and 19.93mm, body widths 6.52mm and 6.18mm, head widths 3.78mm and 3.70mm, and antennal lengths 31.19mm and 45.49 mm. Antennal length or ratio of antennal length to body length overlapped in some ranges between 2 sexes. Therefore antennal length itself or ratio of antennal length to body length could not be used as a definite criterion to discriminate sexes. However, check on color of the antennae of 4,033 adults revealed without exception that basal part of every segment of flagellum of female antenna was covered with whitish-grey hairs, while whole part of every segment of male flagellum was covered with brownish-black hairs. This characteristics might be a best way to differentiate sex of this species.

• Korean Journal of Poultry Science
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• v.48 no.3
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• pp.123-131
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• 2021

In this study, we investigated the effect of separate-sex and straight-run rearing system on the productivity of Korean native chickens. A total of 1,140 GSP-Hanhyup^® Korean native chickens were divided into male, female, and straight-run rearing groups, and the survival rate, body weight, feed intake, and feed conversion ratio were investigated from birth to 12 weeks of age. The average survival rate was 97.9%, and there were no significant differences among the groups. Body weight was significantly different among the groups at all weeks of age (P<0.01). After 4 weeks of age, the male group had the highest weight, followed by the straight-run group, and finally the female group. At 10 weeks, the most uniform body weight was shown in the female group (78%), while the lowest was in straight-run group (44%). Comparing the separate-sex and straight-run groups, male chickens were found to have higher body weights in the separate rearing group than in the straight-run group; however, there was little difference in those of female chickens. Feed intake was the highest in the male group, followed by the straight-run group, and lastly, the female group, while the feed conversion ratio had an opposite trend. Although there is little difference in the production performance of chickens between separate-sex rearing and straight-run rearing system, we concluded that the separate-sex rearing system is much more advantageous than the straight-run rearing system in terms of productivity due to group uniformity.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.245-245
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• 2002