• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.59-62
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• 2016

Many insects have gained increasing attention as an alternative protein for humans. Among those, the two-spotted cricket, Gryllus bimaculatus (Orthoptera: Gryllidae), was recently approved as a general food ingredient by the Korean Ministry of Food and Drug Safety. For industrial utilization of G. bimaculatus, mass rearing techniques and production system should be standardized first. In this study, we investigated the effects of five different feeds on the growth and development of G. bimaculatus. Feed is the one of the key factors that has considerable effects on rearing insects. With five different kinds of feed on $1^{st}$, $3^{rd}$, and $5^{th}$ instar nymphs, the change of survival rate, body weight were monitored up to eight wk after hatching. We concluded that 50% of soybean flour, 20% of corn powder, 10% of rice bran, 9% of milk serum, 10% of rice flour, 0.5% of microorganisms, and 0.5% of multivitamins and minerals (diet C) was the best mix for promoting growth and development of $3^{rd}$ instar nymphs compared to the control diet.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.57-63
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• 2015

Effects of rearing density on growth and survival of the polychaete rockworm Marphysa sanguinea have been investigated in order to develop rearing techniques for this species. This study was examined over a nine-month period in the Fisheries Science and Technology Center of Pukyong National University. Three rockworm densities, 500, 1,000 and $2,000worms{\cdot}m^{-2}$ with weight ranges of < 0.5 g, 0.6-1.5 g, and 1.6-2.5 g, and the no feed control treatment, were stocked in triplicate $0.10m^2$ boxes with sand bottoms. Growth rates were checked with 15 randomly sampled rockworms from each box at months 3, 6 and 9. Results showed that SGRs in all treatments were higher during the first period (0-3 months) than the second (3-6 months) and third periods (6-9 months) for all treatment densities, while SGRs decreased with increasing density. However, survival and growth of worms at high density was not better than low density, but daily biomass production in medium and high density groups was $6.28gm^{-2}day^{-1}$ for the rockworms of 0.6-1.5 g with $2,000inds{\cdot}m^{-2}$, and $12.6gm^{-2}day^{-1}$ for group between 1.6-2.5 g with $2,000inds{\cdot}m^{-2}$, and $14.7gm^{-2}day^{-1}$ for the group of individuals <0.5 g with $1,000inds{\cdot}m^{-2}$. Results showed that M. sanguinea can be one of the most suitable species to commercially exploit in a farming system. In particular, specified densities permit elevated pure production.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.166-171
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• 1997

To find out an alternative prey of Orius strigicollis Poppius in the laboratory continuous rearing system, cotton aphid (Aphis gossypii), two spotted spider mite (Tetmnychus urticae) and mold mite (Tyrophagus putrescenriae) were tested as alternative prey. Development and oviposition of 0. strigicollis were observed at 25f l0C, RH 60-80% and 16L:8D. Survival rate and developmental period of the nymphal stages of 0. strigicollis was 81. 6% and 11.6 days when fed on cotton aphid, 56.796, 14.6 days, 42.3% and 16.5 days when fed on two spotted spider mite and mold mite, respectively. Total oviposition of 0. strigicollis was 68.5 eggslfemaie fed on cotton aphid, 46.1 and 26.5 eggsifemale fed on two spotted spider mite and mold mite, respectively. Cotton aphid seems to be most suitable prey for rearing 0 . strigicollis among the three prey species tested.

• Journal of Sericultural and Entomological Science
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• v.46 no.1
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• pp.18-22
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• 2004

For the purpose of accumulating the research outcomes on Cordyceps and retrieving them efficiently, this study was carried out to identify and standardize the key factors in cultivating Paecilomyces tenuipes and classifying characteristics of Cordyceps. The key factors in cultivating Paecilomyces tenuipes are divided into three major sections according to its stage: silkworm rearing period, cultivation period, and preservation period. Silkworm rearing and cultivation sections are divided into three sub-sections: temperature, humidity, and duration. There are other factors including rearing tools, equipment etc. The key factors in classifying characteristics of Cordyceps are divided into 14 items, 41 divisions on the basis of its general features and its taxonomic features. 14 items contain general article, host, perithecium, conidia, etc. 41 divisions are partitioned by its size and color. The classification system of Kobayasi (1940) or of Shimizu (1994) was adopted for the key factors of Cordyceps species and their anarmorphs.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.100-105
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• 2017

Under natural conditions, black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), colonizes in warm temperate regions, and is active in Korea from May through October. Information on black soldier fly rearing, which is affected by seasonal factors in Korea, is limited. Oviposition by black soldier flies is dependent on light intensity and wavelength. Therefore, continuous mass rearing of this fly requires determination of optimal artificial conditions of illumination. In this study, we compared the number of eggs laid under an artificial light source (750 watt HPL lamp) versus nature sunlight. Our results showed that compared to oviposition under natural sunlight, the use of one or two lamps for 7 hours, resulted in only 43 and 76%, of the total number of eggs laid under natural sunlight, respectively. We also investigated the hatchability of oviposited eggs under artificial illumination and under natural sunlight. The hatching rate under the former was much significantly lower than under the latter. Further detailed research is required to develop methods for successful mass rearing of black soldier fly throughout the year by means of an indoor system.

• Journal of Aquaculture
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• v.8 no.2
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• pp.117-131
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• 1995

In order to improve the present running seawater system for seedling production of marine fishes, rearing experiments with the juveniles of black seabream (Acanthopagrus schlegeli) and oblong rockfish (Sebastes oblongus) were conducted. The recirculating seawater system (F) equipped with the rotating biological contactors and the running seawater system (R) were used. Environmental factors, growth, survival rate and rearing density of the fish were compared between two systems during the experimental period. In the rearing experiment of black seabream, water temperature in F was fluctuated with surrounding air temperature and was higher than that in R. Specific gravity of the rearing seawater in F was relatively stable in the range of 1.0252 to 1.0266, while that in R was greatly fluctuated. pH in F turned out to be 7.51, but pH in R was similar to that in the natural seawater. Dissolved nitrite and nitrate in F were higher than those in R. While no significant differences in the growth of black seabream juveniles were recognized between two systems, survival rates of fishes in F were higher than those of fishes in R. In the rearing experiment of oblong rockfish, water temperature in F was higher than that in R. Specific gravity in F was slightly higher than that in R which showed relatively less fluctuation in the range of 1.0253 to 1.0270. pH in F turned out to be 7.96, but pH in R was similar to that in the natural seawater. Dissolved nitrite and nitrate in F were higher than those in R, but ammonia was lower in F. The juveniles of oblong rockfish reared in F grew significantly faster in their total length and body weight than those in R (P<0.05). However, survival rates of fishes between two systems showed no significant differences.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.27-34
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• 2002

The performances of fish culture were evaluated in the integrated recirculating aquaculture system consisting of a double drain type rearing tank ($2.5 m^3$), a sedimentation tank, a floating bead filter, a foam separator and a rotating biological contactor. A system was stocked with nile tilapia at an initial rearing densities of $5\%$ (A), $5\%$ (B) and $7\%$ (C) oyer 30 days. Feed coefficient was 1.62, 1,79 and 1.80 and average daily growth rate was $0.452\%$, 0.u5% and $0.423\%$, respectively. The level of TAN was maintained below $1 g/m^3$ for $5\%$ of initial rearing density and $2-4 g/m^3$ for $7\%$. The dissolved oxygen level ($2-4 g/m^3$) was not optimum but should not be inhibitory to fish growth. The total suspended solid was completely removed during overall experimental period.

• Women's Health Nursing
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• v.7 no.4
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• pp.518-535
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• 2001

Nursing practices should be based on the understanding of human beings. In order to understand human beings, it is important to study the lifestyles and thoughts of people in their natural environment. In this sense, the cultural aspects of a society need to be studied for a culture-bound nursing service. Child care, which is an important element of nursing, is also strongly influenced by the culture of a society. Therefore, a cultural study is necessary to understand the child-rearing practices of any society. The major purpose of this dissertation is to provide basic foundations for developing a culture-based theory for nursing intervention through studying traditional cultural elements of child care in Korean society. The study examined child-rearing practices in a small village on Koje Island in the southern part of Korea. It utilized ethnographic methodologies including participatory observations and in-depth interviews. The study participants were 9 Korean mothers living on Koje Island. The average age was 52. The data were collected between July in 1998 and December in 1999. The average number of interviews per person was 7-8, and the duration of each interview was approximately 2 hours. The data were analyzed using the Spradley Analytical Method. The following 9 major child-rearing aspects of mothers on Koje Island were discovered as a result of the study: 1. Firstly, mothers on Koje Island were mostly concerned about the "Old Birth Goddess' Curse", especially during their child's early years. This concern was evidenced by their careful behavior when their child was very young and by their praying to the Old Birth Goddess not to be jealous of their babies. 2. Secondly, they wished their children to live a different and better life than themselves. It was represented by their strong motivation toward their children's education as well as their expectation for their children's success. In traditional Korean culture, Korean people think that the rise and fall of the household depend on their offsprings. Therefore, Korean mothers wish their children attain to a higher level of social status through education. 3. Third, mothers are concerned about their children's righteousness. Mothers on Koje island expect their children to live with discretion, justice, strength, respect, harmony, and to do their best in life. 4. Next was an 'anticipation of their children's happy marriage'. The attributes of this category were an 'anxiety about their children's married life', and 'an expectation of a good spouse for their children'. Because Korean people believe that only a son can continue the bloodline of a family, especially Korean mothers have a great concern of the possibility of their daughters not having a son after marriage. Also they have different expectations toward their daughter-in-laws than son-in-laws. 5. Korean mothers also derived their satisfaction from their son. It was characterized by 'excessive affection toward their son', 'dependency on their son', and 'being afraid of their married daughter having a girl like themselves'. Korean society has been a patriarchy. Therefore, a son is beloved as someone who will take care of his old parents, be in charge of ancestral rites, and provide a daughter-in-law who can conceive a son. 6. The sixth category concerned 'the differences in their expectations for their children'. The attributes in this category were 'different expectations depending on their children's gender', 'different expectations depending on their children's ability', and a 'great sympathy toward children with low abilities'. Korean mothers expect their son to become better than their daughter. 7. The seventh category was related to their 'roles in child-caring practices'. Traditionally a child was raised in an extended family system in Korea So it was not the sole duty of a mother to bring up the child. Korean mothers used to receive much help rasing children from their in-laws, and family members. On the other hand, many children grew up by themselves, because their mothers were very busy taking care of housework. Furthermore, many children also grew up in poverty. 8. Mothers also had issues related to 'conflicts in child rearing'. They were characterized by 'lack of understanding', 'rudeness of children', and 'giving vent to one's anger'. 9. Finally, mothers regretted not doing their best in child-rearing practices. It was characterized by a 'bitter feeling of repentance', 'feeling irritated', and 'feeling of unsatisfaction'.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.19-29
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• 2022

The present experiment was conducted to evaluate the effects of single-sex or mixed rearing on the growth and laying performance, blood parameters, egg quality, and feather scores of laying hens in an aviary system. A total of 2,928 (females, 2,856; males, 72), Hy-Line Brown chickens at 20 weeks were evenly assigned to two treatments: termed here the single-sex (only female) and mixed-sex (female to male 20 : 1) conditions. They were allowed an ad libitum diet for 20 weeks in an aviary system. There were eight replicates of each treatment, each consisting of 12.42 m²·birds^-1 (n=183), respectively. The body weight and uniformity in the mixed-sex condition were higher than those in the single-sex condition, but egg production did not show any significant differences between the two types of treatment for 20 weeks. The mixed-sex group showed an effect through stress parameters (corticosterone), whereas the feather score on the back was low at the end of the experiment. These results suggest that the presence of males affect corticosterone level for mating but can reduce the vigilance and aggressive behavior of laying hens.

• Journal of the Korean Home Economics Association
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• v.50 no.8
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• pp.41-52
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• 2012

The purpose of the current study is to examine the role of mothers' personality traits in predicting their parenting stress. The study subjects were married working woman who live at Gyeonggi-do and has their first child studying in elementary, middle, or high school. Collected data were analyzed with SPSS WIN 18.0 program. The results were as follows.: First, it has been shown through examination of the general tendency of observation subjects' relative factor, that many have above average parenting stress. The compositing factor for parenting stress were mainly the burden and distress of the parent role. Second, the differences in parenting stress were affected by relative variables in accordance with the general features of the study object. If the younger the parent, the higher the education, the lower the age of the first child, and if there were a child assistant after school, the parenting stress became larger. Third, after controlling for demographic characteristics, employed mothers' neuroticism significantly predicted greater parenting stress. When mothers had more conscientiousness and openness, they reported less parenting stress which implied that interpretation and perception of child rearing experiences can vary depending on personality and predict parenting stress of working mothers.