• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.2
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• pp.54-59
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• 2019

Yellow mealworms (Tenebrio molitor Linnaeus) are very promising insects for the food and feed industry. Because mealworms are in the spotlight as an alternative protein source in the future, it is necessary to develop efficient rearing techniques for mass production. To evaluate the effects of brewer's yeast (BY) on the growth of mealworms, Tenebrio molitor Linnaeus, the mealworms were fed with wheat bran (WB) diets containing different levels of BY (0, 10, 30, 50, and 70%). Larval survival, larval weight, development time, pupal weight and eclosion rate were monitored for 12 weeks. The results showed that mealworms fed on the diets containing 30% and 50% of BY have significantly higher weight gain, specific growth rate and daily weight gain, and lower larval duration than fed the control diet (100% WB) and other BY diets (10% and 70% BY). Larval survival on the diets containing 30% and 50% of BY was higher than on control diet. Pupal weight and eclosion rate were not significantly different among all diets. In conclusion, we suggest feeding the diet containing 30% of brewer's yeast with wheat bran in order to increase the production of mealworms.

• International Journal of Industrial Entomology and Biomaterials
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• v.40 no.2
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• pp.41-50
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• 2020

Vermicompost, manure, compost and organic fertilization are ecofriendly. Nowadays, many products resulted from sericulture consumed by humans such as mulberry leaves, fruits, mulberry tea, silk and natural silk cosmetics. Soil applications of three treatments with vermicompost (0.5, 1 and 2 tons per 0.42 hectare) and recommended rate of mineral fertilizers of nitrogen phosphorus potassium were used for investigation. Impact of fertilization on mulberry plant traits of moisture, number of shoots/tree, total shoots length/tree, number of leaves/shoot, number of leaves/ (100g), leaf yield/tree and leaf yield of fadden/season were recorded. In addition the effect of fertilization on larval and cocoon characters of young instar duration, fifth instar duration, total larval duration, larval mortality percentage, weight of third instar larvae, weight of fourth instar larvae, weight of fifth instar larvae, fresh cocoon weight, fresh shell weight, pupae weight, cocoon shell ratio, silk productivity, cocooning percentage, pupation ratio, number of cocoons/ liter, crop cocoons by number, crop cocoons by weight, fecundity and fertility. Using vermicompost treatment was enhancing plant characters. Treatments of V₃, V₂ and V₁ were shortage young, fifth and larvae durations. Mostly feeding silkworm during the whole larval duration on treated mulberry leaves with vermicompost improving the traits average. Using vermicompost for fertilization by rate of V₃ and V₂ is better than others for cocoon characters for females and males.V₃ and V₂ of vermicompost per 0.42 hectare is recommended for rearing mulberry silkworm instead of mineral fertilization.

• Journal of Apiculture
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• v.33 no.4
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• pp.261-268
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• 2018

Queen honey bees (Apis cerana) can be reared artificially on demand by the use of grafting technique. The technique consists of grafting young worker larvae into queen cell cups and raising in a queenless strong colony. As the age of grafted larvae for queen rearing exhibited several aspects related to quality and reproductive potential of queen, this study were conducted to investigate the influence of age of grafted larva on morphological characteristics and lifespan of queen, and the growth of colony she headed. Our results demonstrated that queens reared from young worker larvae (i.e., less than 1-day old larvae) were significantly larger in size (i.e., body weight and thorax width) than that of queens reared from 2-day old worker larvae. Moreover, queens reared from younger worker larvae initiated egg-laying earlier, stored more spermatozoa in spermatheca and had a longer lifespan compared to queens raised from older worker larvae. We also found a significant positive effect of queen grafting age on the production of worker and drone brood, adult worker population in colonies headed by queens reared from younger larvae. These findings suggested that rearing queens from brood grafted at the earliest possible age could increase the reproductive potential of queen as well as fitness of colony she head.

• International Journal of Industrial Entomology and Biomaterials
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• v.46 no.1
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• pp.1-8
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• 2023

Mulberry (Morus spp.) production is a vital activity in sericulture along with rearing of silkworms (Bombyx mori L.) for silk production. The Sericulture Research and Development Institute (SRDI) conducted a study that evaluated 11 mulberry varieties, including nine newly-evolved mulberry hybrids and two check varieties. These mulberry varieties were fed to silkworm hybrid, DMMMSU 115 x 100. The rearing performance of DMMMSU 115 x 100 was determined based on the silkworm economic traits such as weight of 10 matured larvae, cocoon weight, shell weight, shell percentage, cocoon yield, reelability percentage, filament length and filament size. Six silkworm rearing trials were conducted with 50 silkworm larvae per treatment in three replicates. The data were analyzed in a one-way Analysis of Variance. Significant differences were tested further using Tukey's Honest Significant Difference. Mulberry varieties that garnered an evaluation index value of higher than 50 were identified and selected. Results of the study revealed significant variations among the mulberry varieties based on the parameters gathered except on the reelability of cocoons, filament length and size. Matured silkworm larvae fed with Alf 55 were significantly heavier and higher cocoon yield compared to those fed with Alfonso and S₅₄. Alf 32, Alf 55, Alf 58, Bat 37 and Bat 73 were identified as potential varieties and highly recommended as feed for the silkworm hybrid, DMMMSU 115 x DMMMSU 100.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.79-87
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• 2004

The silkworm rearing and growth parameters of 63 multivoltine silkworm accessions under extended period of egg preservation at 5$^{\circ}C$ from 30 days to 45 days were studied. The results indicate that, nine accessions did not respond to extended period of egg preservation at low temperature and the remaining 54 accessions responded to the treatment and three rearings were conducted for comparision with the control; to estimate the effect of prolonged egg preservation at low temperature. The non-parametric tests statistics (Wilcoxon tests) was adopted for comparing the mean performance of treated batches (45 days) over the control (30 days). Highly significant variability was found among the accessions for all the parameters under study. The genetically controlled morphological characters were not altered in the treated batches, which were found to be on par with that of control. However, the total larval duration varied significantly over the control in 51 accessions. Similarly, the fifth age larval duration of 27 accessions showed decreasing trend compared to control. Altogether 41 accessions were found to be tolerant to long-term cold preservation upto 45 days, without showing any significant variation for morphological as well as essential quantitative traits. These accessions may be recommended for long-term egg preservation schedule up to 45 days, which will reduce the cost of conservation of these silkworm germplasm.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.69-78
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• 1965

1. In younger larval stages, the incubation period of Spicaria pracina was showed to generally last for 8 days after the inoculation of 1st instar, for 11 days after that of 2nd instar, and for 12 days after that of 3rd instar. 2. The more the inoculum of spore is, the more silkworm jundices appear severely throughout all stage except 1st instar. 3. Especially in matured larval stages, more death rate due to silkworm jundice was showed to appear than that due to green muscardine and the more the larvae became mature, the more the loss due to jundice were severe. 4. Among other inoculum, the control by 5 per cent cerisan lime resulted in getting the best economical effect while this chemicals did harm to the silkworms, being of 20.1 per cent death rate.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.115-123
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• 2003

Oviposition and egg laying is an important physiological and behavioural event in the life cycle of the silkworm, Bombyx mori (L). Oviposition and egg laying is dependent on a number of intrinsic and extrinsic factors viz., neural, hormonal, environmental, physical, behavioral etc for the perpetuation of population. Although, the virgin female moths have fully developed embryos but active egg laying begins under the influence of mating which provides essential copulation stimulus for oviposition. After mating drastic biochemical changes occurred that incites egg laying under the influence of optimum environmental conditions. Weight of pupae as well as larval density has significant role on oviposition and egg laying behaviour in the silkworm wherein high pupal weight and inadequate rearing space affects not only the biology, morphology and physiology but also the oviposition and egg laying. Surface topography, plane of inclination, mating length, age of male moth, temperature and photoperiod etc has significant effect on reproductive physiology of silkworm. An attempt has been made in this review article to elucidate briefly the works carried out on mating behaviour, direct and indirect copulation stimulus, vitellogenesis, influence of environmental factors besides effect of weight of pupae and or pharate adult and larval density on oviposition and egg laying behavior in the silkworm, B. mori and its significance in silkworm seed production.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.132-138
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• 2020

Marphysa sanguinea is the most well-known polychaete species with a high economic value. However, this species has a high mortality in the early rearing stage of aquaculture. This study was conducted to find out the optimal substrate size and organic contents for the growth and survival rate of M. sanguinea larvae and juveniles. It was observed that the smaller grain size (<Ø 0.063 mm) and high organic contents (5-10%) induced settlement and reduced settlement time of larvae. Moreover, the growth and survival rate of larvae reached high levels at Ø 0.004-0.016 mm of grain sizes and 5-7.5% of organic contents as advantageous substrates for settlement. The survival rate of juveniles reached over 90% in less than Ø 0.016 mm substrate on 15-day experiment for different grain sizes of substrates. These results indicated that substrate compositions of less than Ø 0.016 mm of sand size and 5-7.5% of organic contents in mud will enhance the productivity of M. sanguinea at the early stage.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.78-83
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• 1999

Sublethal effects of imidacloprid (30 and 100 ppm) and insect growth regulators; flufenoxuron (3 and 10 ppm), triflumuron (10 ppm), and teflubenzuron (3 ppm), were tested by treatment via larval rearing medium of a housefly, Musca domestica, in laboratory. Pupal weight was significantly reduced by treatment to the 3rd larvae with high concentrations of imidacloprid (100 ppm) and flufenoxuron (10 ppm), and the adults that survived the flufenoxuron 10 ppm treatment deposited significantly fewer eggs compared with controls and other treatments. Adult longevity and egg viability, however, were not affected by any of the treatments.

• Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.228-234
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• 2005

Despite the relatively high production of fingerlings of the olive flounder Paralichthys olivaceus, its larval rearing in terms of first feeding has not been fully analyzed. We evaluated the variations of amino acids and fatty acids of starved larvae over 96 hr after hatching. We also investigated depletion of the yolk and oil globule of starved larvae and those fed the rotifer Brachionus plicatilis. In addition, the optimum size of the rotifers according to the mouth size of the larvae, and the point of no return with delay of the first feeding, were also examined. The amino acids in the egg decreased abruptly during embryo development. At 48 to 72 hr after hatching, the amino acids of starved larvae decreased by $30-40\%$ from the level in newly hatched larvae. The concentrations of fatty acids in newly hatched larvae were lower than those of floating eggs and dropped sharply at 48 hr after hatching, when the yolk disappeared. The starved larvae depleted their yolksacs and oil globules earlier than the fed larvae did. At 84 hr after hatching, rotifers were detected for the first time in the guts of the larvae, which were about 3 mm in total length. The point of no return appeared to be close to the fourth day from the first feeding. For a high survival rate of P. olivaceus larvae, the first feeding should occur before the third day after hatching.