• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.75-79
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• 2003

Oral supplementation of zinc chloride to silkworm larvae in different concentrations (30, 60 and 90 ${\mu}g$/ml) to the fourth and fifth instar resulted in a significant increase in commercial traits, like larval weight, silk gland weight, cocooning percentage in lower concentrartion (30 ${\mu}g$) treated group. The female cocoon weight, shell weight and its ratio were significantly increased in 30 and 60 ${\mu}g$ treated groups, male cocoon weight, and shell weight in 30 ${\mu}g$ treated group and its ratio in 60 and 90 ${\mu}g$ treated groups, filament length, weight and moth emergence percentage in all the treated groups and egg productivity in 90 ${\mu}g$ treated group were increased significantly. The remaining groups did not show any significant changes compared with that of carrier control.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.57-61
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• 2003

A new silkworm variety, Chugangjam, with a sex-limited larval marking and high silk yielding for summer-autumn rearing season is $F_1$ hybrid between Jam 147, a Japanese race bred from P8503/8453, and Jam 148, a Chinese race from M8306/Jam 130. Jam 147, Japanese parent of the Chugangjam showed a high GCA (general combining ability) in pupation percentage and Jam 148, Chinese parent, showed a high GCA in pupation percentage and single cocoon weight. In the local adaptability test performed at 8 local areas in autumn of 2001, Chugangjam was 5% higher in cocoon yield and 8% in raw silk productivity in the 10,000 of the 3rd molted larvae, respectively, than the check variety Daesungjam.

• Journal of Aquaculture
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• v.11 no.3
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• pp.345-352
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• 1998

The effect of starvation on the growth and hepatocyte nuclear size of larval rockfish Sebastes schlegeli and spotted sea bass Lateolabrax sp. were studied. The growth of total length and wet weight in both rockfish and spotted sea bass starved were lower than their control counter-parts. The nuclei sizes of parenchymal cells in the liver of rockfish and spotted sea bass were correlated with the nutritional status of their first-feeding larvae. The result suggested that hepatocyte nuclear size in rockfish and spotted sea bass could be used as an alternative indicator for the identification of starving condition and such karyometry might be criteria for evaluating the successful transition from endogenous to exogenous feeding regime.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.127-135
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• 2007

Precocious metamorphosis was induced in two popular bivoltine breeds i.e. YB and $NB_4D_2$ by an imidazole compound having anti-juvenile hormone activity. The chemical was administered by feeding treatment with mulberry leaf to freshly moulted (0-6 hrs) IV instar larvae. The dose of the chemical was found to be breed specific being 650 ppm for YB and 500 ppm for $NB_4D_2$. The chemical caused complete skipping up of the fifth instar larvae which is most susceptible to diseases. But IV instar was somewhat prolonged. As a result the total larval period was reduced by 4-5 days. However, some of the rearing and reeling parameters like cocoon yield, cocoon weight, shell weight, shell %, filament length and fecundity were reduced for that particular generation only. The effective rate of rearing (ERR %) was significantly increased in trimoulters during the most unfavourable August - September seed crop season. Number of cocoons / kg and number of male moth were significantly higher in trimoulters. These may be useful for preparation of $multi{\times}bi$ hybrid seed. Fine denier was also found in trimoulter cocoon which is the cause of getting fine silk filament from trimoulter cocoons. Normal mating behaviour and emergence pattern was recorded in trimoulters. Bivoltine trimoulter males also showed competence for mating with multivoltine females. These results suggest the possibility of getting trimoulter males during hot and humid seasons when rearing of bivoltine is almost impossible particularly in Eastern and North Eastern India.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.48-54
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• 1997

This study was conducted to determine the effect of temperatures and food sources on the egg and larval developmentof the tobacco cutworm, Spodoptera litura Fabricius. The hatchability of egg masses of S. liturawas 100% on the leaf of soybean, perilla and sweet potato in any given temperature regimes, while the hatchabilitywas only 65-8796 when reared on the pulp paper and decreased as temperature increased. Egg durationwas not significantly different among different food sources within each temperature. However, egg duration at32$^{\circ}$C was shorter than that at 24$^{\circ}$C and 28$^{\circ}$C. During the early larval development, at 28$^{\circ}$C and 32$^{\circ}$C the larvafed on sweet potato leaf was heavier than those fed on soybean and perilla leaves and the opposite case wastrue during mid-larval development stage. However, larval weight at 24$^{\circ}$C was heavier on sweet potato leafthan that on soybean and perilla leaves until 12 days after hatching. This result was probably due to relativelyslower developmental rate at 24$^{\circ}$C compared to 28$^{\circ}$C and 32$^{\circ}$C. The mean larval mortality was 68.896, 44.5%and 33.8% at 24$^{\circ}$C. 28$^{\circ}$C and 32"C, respectively. The lowest mortality was observed on soybena leaf and followedby perilla and sweet potato leaves, and artificial diet regardless of temperature conditions. The durationwas the shortest when they fed on soybean leaf, and followed by perilla and sweet potato leaves and artificialdiet. Larval durations were 23.6-30.4 days at 24$^{\circ}$C. 18.6-22.3 days at 28$^{\circ}$C and 14.5-18.0 days at 32$^{\circ}$C. Thethreshold temperatures of egg and larva of S. litura were about 6.l"C and 10.9"C, respectively.t 6.l"C and 10.9"C, respectively.pectively.

• Journal of Sericultural and Entomological Science
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• v.16 no.1
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• pp.77-84
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• 1974

In autumn season residual period of nicotine is observed in the larval duration, weight of molting larvae at the various stages, percentage of delayed molting larvae, and survival rate up to the 3rd stage from the 1st season to the 3rd season and up to the stage for four seasons, respectively. Mulberry tree is planted in pot from June 18, 1973 to August 4, 1973 and placed every other row between tobacco variety of Hicks cultivated in mulching system and control is prepared in the Sericultural Experiment Station, placing in the every ridge of mulberry field with the four seasons ; 5 day isolation (1st season), 15 day isolation (2nd season), 25 day isolation (3rd season), and 50 day isolation (4th season). 1) 1st and 3nd instar larvae fed with the tobacco stained mulberry leaf has longer larval duration for the four seasons, as compared with those of the control, increasing 12％ in index with 28 hours, 17％ in index with 37 hours, 23％ in index with 50 hours, 17％ in index with 43 hours from the 1st season to the fourth season and the 3rd to the 4th instar larvae, increasing 18％ in index with 55 hours. 2) 2nd instar molting larvae, 3rd instar molting larvae from the 1st to the 4th season and 4th instar molting larvae at the 4th season decrease their larval weight respectively, as compared with the control. 3) Percentage of delayed molting larvae from the 3rd stage to the 4th stage goes up higher than that of the control in the End larval stage at the 3rd to the 4th season, in the 3rd larval stage at the 1st, the End, and the 4th season, and in the 4th larval stage at the 4th season, respectively. 4) Survival rates in the 2nd larval stage at the 2nd season to the 4th season, in the 3rd larval stage at the 1st to the 4th season, and in the 4th larval stage at the 4th season respectively are higher than that in the control.

• Journal of Life Science
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• v.29 no.9
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• pp.996-1001
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• 2019

Edible insects are reported to be rich in protein, minerals and vitamins, and much attention has been paid to them as a future food source. In Korea, they were massively reared and sold. In order to enhance the market value of edible insects for industrialized mass production, it is important to develop the safe and nutritious feed sources for rearing them are needed. In this study, a chlorella-free control feed (Exp1) and six experimental feeds supplemented with 0.5~2.0% liquid or powder types of chlorella were formulated. Protaetia brevitarsis and Allomyrina dichotoma, registered as food ingredients in Korea, were fed with the designed feeds and parameters of growth including larval survivorship, larval body weight, and larval period were analyzed. When chlorella added, larval survivorship was increased 2~13%(p>0.05) and 9~22%(p<0.05) in each beetle compared to the control. Interestingly, the larval period of chlorella powder-added groups was shortened by 24 days (Exp3, p<0.05) in P. brevitarsis and 19 days (Exp4, p<0.01) in A. dichotoma. Meanwhile, some parameters, crude protein, crude fiber, copper, zinc, potassium, magnesium, and phosphorous, in chlorella-added groups of P. brevitarsis were also higher than the control group. Therefore, chlorella could promote the larval growth performance of these two beetles and be used as a feed additive in rearing them.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.75-78
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• 2015

The white-spotted chafer, Protaetia brevitarsis (Coleoptera: Scarabaeidae), is an economically important insect in Korea. Traditionally, it has been regarded as a medicine for preventing liver-related diseases and suppressing liver cancer. Recently, this beetle was enlisted as a temporal food ingredient by Korean Ministry of Food and Drug Safety. Therefore, this beetle is focused as a one of the important insects that are commercially reared and sold in Korea. As the economic importance of this beetle is growing, the suitable rearing conditions are needed for more detailed investigation. In this study, we compared three temperature conditions and two food additives, rice chaff and soybean cake, for its effects on the body weight change of third instar larvae of P. brevitarsis. Temperature is a major environmental factor that has tremendous effects on rearing insects. In additions, rice chaff and soybean cake are byproducts of other agricultural activities. Therefore, it is easy to get, and the price is comparatively low. However, they still have meaningful amount of nutrients. With four different kinds of feed and three temperature conditions on the third instar larvae of beetles, the body weight change was tracked for 14 wk. We concluded that 27.5℃ is the optimal temperature to rear the third instar larvae among three temperatures (25, 27.5, and 30℃). Among four different feeds, conventional fermented oak saw dust with rice chaff and soybean cake was the best feed for larval weight gain during 14 wk. However, feed with soybean cake at 30 ℃ was the best condition for rearing P. brevitarsis larvae when temperatures and feeds were compared at the same time.

• Current Research on Agriculture and Life Sciences
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• v.32 no.4
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• pp.185-188
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• 2014

The movement, survival, and weight gain of Helicoverpa armigera $H{\ddot{u}}bner$ (Lepidoptera: Noctuidae) first instar larvae were studied on CB9, CB10 and SR05 cotton varieties under field conditions. The neonate H. armigera were released on the cotton varieties at the squaring stage of the plants and, after a period of 72 hours, the survival, weight gain, and final location of the larvae were observed. While the different cotton varieties had no effect on the survival and weight gain of the larvae, the release locations on the cotton varieties had a significant influence on the larval survival and weight gain. The larvae fed small squares of the cotton varieties were significantly heavier and showed a higher mortality than the larvae fed leaflets and mature leaves. For the cotton varieties in this study, the larvae released on leaflets showed a significantly higher rate of recovery compared to the larvae released on mature leaves and squares. This study also found that that the larvae on leaflets did not move up or downward unlike the larvae on mature leaves and squares. This information on the foraging behavior of larvae on cotton varieties will assist researchers to interpret field data and thereby help with the development of pest management decisions.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.3
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• pp.113-119
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• 2011

This study was designed to determine the effects of larval extracts from Protaetia brevitarsis seulensis shade dried larva from Korea and China on liver tissues of hepatic injury groups. The experimental groups are divided into five groups; Normal, carbon tetrachloride single injection ($CCl_4$), Pb-CHI ($CCl_4$ + P. brevitarsis shade dried larva from China), Pb-KOR ($CCl_4$ + P. brevitarsis shade dried larva from Korea) and SIL ($CCl_4$ + 0.35% silymarin) groups. Sprague Dawley rats were oral injected with $CCl_4$ at a dose l mg/kg (20% in corn oil) for induction of liver damage for 4 weeks. Each experimental group was fed with a dose 50 mg/kg of larval extracts based on medicinal preparations from 3 weeks to 4 weeks after $CCl_4$ treatment. At the end of 4 weeks, we evaluated the serum levels of glutamate-oxaloacetate transaminase (GOT), glutamate-pyruvate transferase (GPT), alkaline phosphatase (ALP) and blood urea nitrogen (BUN) in serum and the cytokine levels of tumor necrosis factor-${\alpha}$) (TNF-${\alpha}$) and transforming growth factor-${\beta}$ (TGF-${\beta}$) in the cells isolated from spleen and liver. The histological analysis was also conducted. The $CCl_4$ injection reduced body weight, induced congestion of middle lobe and hepatocytic degeneration, resulting in disintegration of hepatic cords, and increased biochemical markers of blood related to hepatic injury. On the other hand, the Pb-CHI and Pb-KOR group decreased the levels of biochemical markers in blood and cytokine levels in spleen and liver. Especially, the Pb-KOR group facilitated the recovery of biochemical values of blood related to hepatic injury, hepatic lesions and fibrosis. Taken together, larval extract from P. brevitarsis might prevent acute hepatotoxicity and enhance the recovery of liver fibrosis and cirrhosis induced by $CCl_4$, and the ingredients could be a promising candidate for the prevention and treatment of hepatic disorders.