• International Journal of Industrial Entomology and Biomaterials
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• v.48 no.1
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• pp.33-41
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• 2024

To investigate the effect of sawdust fermentation period and storage period after fermentation on development as food for P. brevitarsis larvae, individual and group breeding were conducted on berry sawdust and oak sawdust. In individual breeding, the growth period of P. brevitarsis larvae was reduced by 12 days from the 60-day fermentation of berry sawdust to the 40-day fermentation of berry sawdust, 30 days from the 90-day fermentation of oak sawdust, and the weight of the larvae was the heaviest. In group breeding, the time it takes for P. brevitarsis larvae to change from 1^st to 3^rd instar is about 30 days after hatching from 60-day fermentation of berry sawdust, while 90-day fermentation of oak sawdust took more than 60 days, so the growth speed was fast and the survival rate was good. The results of the farmhouse demonstration test were the same trend, and it was judged that it would be possible to produce P. brevitarsis larvae with berries fermented sawdust, and it would be advantageous in terms of economy. In addition, for both individual and group breeding, the growth period of P. brevitarsis larvae was longer as the storage period was longer, the weight of the larvae decreased, and the survival rate was no different. The development period of P. brevitarsis larvae was the longest in the storage period of 18 months for berries fermented sawdust, and the storage period of oak fermented sawdust was longer in the storage period of 12 months and 18 months. Therefore, considering the results of individual breeding and group breeding, the fermentation period was appropriate for 60 days for berries sawdust, and the storage period for berries sawdust was stable from 0 to 12 months, and 0 to 6 months for oak sawdust.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.107-110
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• 2001

Variations in protein and nucleic acid concentrations were observed in 24 hrs old eggs and hatched larvae of Nistari strain, Bombyx mori, exposed to starvation. Three starvation treatments of 24,48 and 60 hrs were given separately from 0 hr old fifth instar larvae. Biochemical variations were studied in the resultant hatched larvae of one time starved parent, while the eggs obtained from parents receiving starvation in two successive generations were considered for the study. In hatched larvae, protein levers in 24 hrs starvation groups remained significantly higher over control (never starved) while the same was found to be lower in 48 and 60 hrs starvation individuals. The RNA concentration remained significantly higher in all the treated lots. However, DNA content was not found to be significantly altered in hatched larvae after exposure to feeding stress. Protein, RNA and DNA concentration of 24 hrs old eggs produced by all the starved groups of Nistari, which had deceived two consecutive starvation during parental generations, showed higher concentrations of these biomolecules over control. Hence, starvation induced alterations in protein and nucleic acids in eggs and hatched Iarvae are indicative of a preparatory phase adopted by the insect to acclimatise itself and its progeny to stress situations.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.1
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• pp.20-24
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• 2015

Increased use of rhinoceros beetles (Allomyrina dichotoma ) for food and medicine, and their elevated value as pets has led to an increase in the number of their breeding farms. Mass breeding of the insects in these farms leads to entomological diseases. In this study, we investigate cannibalism resulting from overcrowded breeding of A. dichotoma larvae, as well as secondary fungal infections in epidermal wounds in the surviving larvae. Some of the fungi detected in the present study showed entomopathogenicity, and the larvae showed different times of death. In particular, larvae infected with Clonostachys sp., an endophytic plant fungus, grew for a long time after infection, but died without pupating.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.544-551
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• 2020

Background: Previous studies have shown the insecticidal efficacy of ginsenosides. In the present study, we aimed to investigate the metabolic mechanism related to the inhibitory effect of panaxadiol saponins (PDSs) against the Asian corn borer Ostrinia furnacalis (Guenee). Methods: Third instar larvae of O. furnacalis were fed normal diets with different concentrations of PDSs for 4 days. The consumption index, relative growth rate, approximate digestibility, and conversion of ingested and digested food were recorded. A targeted gas chromatographye-mass spectrometry assay was performed to detect the profiles of amino acids, fatty acids, and carbohydrates in larvae of O. furnacalis. In addition, the activity of detoxification-related enzymes was determined. Results and Conclusions: PDSs decreased the consumption index, relative growth rate, approximate digestibility, and conversion of ingested and digested food in the 3rd instar larvae of O. furnacalis in a dose-dependent manner. PDSs decreased 15 free amino acids, 16 free fatty acids, and 5 carbohydrates and increased the levels of palmitoleic acid, palmitic acid, and 9-octadecenoic acid in the 3rd instar larvae. The activity of detoxification-related enzymes, such as acetylcholinesterase, glutathione S-transferase, cytochrome P450, carboxylesterase, trehalase, acid phosphatase, and alkaline phosphatase, was reduced in a dose-dependent manner in the 3rd instar larvae exposed to PDSs. These data confirmed the inhibitory effect of PDSs against growth, food utilization, and detoxification in the 3rd instar larvae of O. furnacalis and the potential for using PDSs as an efficient tool for insect pest management for O. furnacalis larvae.

• Journal of Environmental Science International
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• v.30 no.2
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• pp.191-194
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• 2021

This study aimed to provide information and data for the management of insect breeding farms by identifying the appropriate density when rearing Protaetia brevitarsis larvae. The breeding box of the insects was filled with 2 L of fermented sawdust on a 50 × 35 × 15 cm sheet of plastic, and the density of the treatments was 200, 300 and 400 P. brevitarsis in the first, second, and third larval stages. Each treatment was repeated five times, and the sawdust medium was replaced three times (10 intervals). The experiments were conducted for a total of 30 days from March 1, 2020. Overall, 200 P.brevitarsis in the first, second, and third larval stages reared in the breeding box had a higher average survival rate and lower average mortality rate, thereby contributing to efficient production. In conclusion, this result suggests a way to increase production efficiency through the environmental management of insect breeding farms.

• Journal of Ecology and Environment
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• v.44 no.4
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• pp.207-211
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• 2020

Adult land crabs generally live on land while their larvae live in the sea. In the case of Sesarma haematoche, female crabs migrate from land to sea to release the larvae at the high tide of syzygy night. Artificial structures along coastal areas are being obstacles for the migration of land crabs and causing synchronized roadkills on coastal roads during breeding migration. In this research, we compared the sex ratios of crab populations in coastal areas with coastal roads and uninhabited island areas with no road. The proportion of females in inland habitats with coastal roads was significantly smaller than island habitats. In particular, females are exposed to the risk of annually repeated roadkills, and the proportion of females decreases rapidly with their growth. If this tendency is general for land crab populations in the coastal areas with roads, significant road mortality of female land crabs during breeding migration can lead to severe population decline in coastal areas. Therefore, it is necessary to take an action to save land crabs crossing coastal roads.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.51-57
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• 2006

Culex pipiens complex larvae were found at the septic tanks in Busan and Ulsan cities located in South-eastern area of Korean peninsula. The larvae were collected in 25, 35 and 75 septic tanks out of 3,527, 622 and 1,111 septic tanks which the breeding rates were averages of 0.7%, 5.6% and 6.8% in Busan from January to May, 2003; Busan from February to March, 2004; and Ulsan from January to April, 2005, respectively. The average numbers of the mosquitoes in the tanks were 38.8, 14.9 and 13.7 larvae/dip with a 355-ml dipper. The larval densities were from 25.4 larvae/dip in January to 43.7 larvae/dip in April. 2003 which were not significantly different between them. It was the first report to find mosquito breeding at septic tink in Republic of Korea. Culex pipiens larvae were found in 6 out of 379 septic tanks at complex buildings (over $2,000m^2$ in size) in Ulsan from June to September, 2005, having an average of 1.6% for mosquito breeding rate. The mosquito larvae were collected in 8 and 530 septic tanks out of 210 and 3,729 septic tanks at large (over 300 homes) and small apartments (below 300 homes) with 3.8% and 14.2% of the average breeding rates, respectively At the septic tanks of private houses for below 50 persons, 708 out of 7,178 septic tan had Cx. pipiens larvae and pupae with 9.9% of the average breeding rate. Total average of the mosquito breeding rate was 10.9% of the investigated septic tanks of residential buildings in Ulsan. The number of mosquito larvae in the septic tanks were 15 to 75 larvae/dip. The bent net sets of septic tanks prevented from mosquito breeding to the rate of 93.1%.

• Development and Reproduction
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• v.18 no.2
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• pp.99-106
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• 2014

Fish larvae are immediately exposed to microbes from hatching to maturation of their lymphoid organs, therefore effective innate mechanisms is very important for survival. However, the knowledge of the development of immune system in fish is limited and in demand now. In vertebrates, recombination-activating gene 1 (RAG-1) and immunoglobulin M (IgM) have been considered as very useful markers of the physiological maturity of the immune system. In this study, the expression of the both genes was assessed throughout the early developmental stages of olive flounder larvae (5-55 dph) and used as markers to follow the development of immune system. RAG-1 and IgM mRNA expression was detectable at 5 dph and remained so until 55 dph. These patterns of expression may suggest that the olive flounder start to develop its function around 5 dph. Tissue distribution was found that both genes mRNAs are only expressed in the immune-related organ such as spleen, kidney and gill. The early detection of IgM mRNA led to the investigation of its presence in oocytes. Both RAG-1 and IgM mRNA transcripts were detected in unfertilized oocytes, suggesting that they are maternally transferred. The biological significance of such a phenomenon remains to be investigated.

• Development and Reproduction
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• v.17 no.4
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• pp.311-319
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• 2013

Fish larvae are immediately exposed to microbes from hatching to maturation of their lymphoid organs, therefore effective innate mechanisms is very important for survival in such an environment. The key component of innate immune system, C3 is central protein of all activation pathways of the complement system, leading to inflammatory reactions, such as opsonisation, chemotaxis, and cell lysis of pathogens. Although, innate mechanisms is essential for survival in the early stage of development, little is known about defence mechanisms. In this study, the alignment analysis showed that amino acid sequence of C3 from olive flounder liver EST homologous to other known C3 sequences with 73-99% identity. Also, we examined the tissue distribution of olive flounder C3 and analyzed expression pattern from the fertilized egg until 28 days post hatching. As a result, olive flounder C3 mRNA was expressed only in the liver and the mRNA level more increased as developmental proceed during the early stage. These results may suggest that olive flounder C3 plays an important function in the early immune response of olive flounder larvae.

• Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.213-224
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• 2024

Betta rubra, classified as endangered fish species by the International Union for Conservation of Nature (IUCN), has been successfully bred and raised in captivity for two generations under laboratory conditions. This study aimed to provide comprehensive information on the captive breeding of B. rubra, focusing on various parameters crucial for ex-situ conservation and domestication. The research involved breeding trials, embryo and larvae observation, first feeding experiments, larva and fry rearing trials, and the evaluation of growth and reproduction in two generations. The study revealed that the female B. rubra, with an average total length of 5.17 ± 0.15 cm and weight of 1.61 ± 0.06 g, produced an average of 73.67 ± 7.09 eggs, 34.33 ± 5.13 total larvae, and exhibited a hatching rate of 46.67 ± 5.77%. The embryogenesis process commenced on the day of spawning (dps) and continued until the eggs hatched at 6 dps. Larvae development and yolk absorption occurred from 0 to 6 days post-hatching (dph). The study also examined the impact of different initial feeding options, with chopped Tubifex resulting in the most significant in- crease (p < 0.05) in length. The growth pattern of B. rubra larvae showed slow initial growth during the first seven days, followed by a rapid exponential growth phase from day 8 to day 39. Two generations of B. rubra (G1 and G2) were successfully bred in captivity, with G2 showing a better tendency for growth in length and weight compared to G1. Notably, there were no significant differences (p > 0.05) in reproductive success between the wild-origin broodstock (G0), G1, or G2. This research contributes valuable insights into the captive breeding of B. rubra and its early life stages, offering critical information for the conservation and sustainable management of this endangered species. Further research is needed to explore the long-term effects of domestication on behavior, physiology, and phenotypic diversity.