• 한국임상수의학회지
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• 제21권3호
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• pp.248-252
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• 2004

DNase activity from infective larvae of the parasitic nematode Haemonchus contortus was characterized and compared to that from whole worm. DNase activity from infective larvae was detected throughout pHs 4-10, but high activity was detected under acidic conditions. The activity was not inhibited by 10 mM EDTA at pH 5.0, but was significantly inhibited at pH 7.0. The activity produced DNA, fragments with mixtures of 3'-hydroxyls (OH) and 3'-phosphates (P) at each pH with predominance of 3'-P. A unique DNase activity at 37 kDa was identified from infective larvae on zymograms. The 37 kDa DNase was detected only at pH 5.0, but not at pH 7.0, and this activity was not inhibited by EDTA at pH 5.0. These characteristics of the 37 kDa infective larval DNase resemble those of classic acidic DNases (e.g., DNase II). In contrast, 34, 36 and 38.5 kDa DNase activities were shown to be specific for whole worm. This result demonstrated that DNases in H contortus are regulated during development.

• Journal of Animal Science and Technology
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• 제62권5호
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• pp.741-752
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• 2020

Herein, the in vitro protein digestibility of lyophilized Protaetia brevitarsis larvae flour with and without defatting using 70% ethanol was compared with beef loin. Proximate analysis showed that the defatted larvae contained the highest protein content (p < 0.05). The viable counts of total aerobic bacteria, Escherichia coli, and coliform bacteria decreased significantly after defatting the larval samples with 70% ethanol (p < 0.05). Measurement of α-amino group content and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed higher amounts of low molecular weight proteins in the larvae compared to beef loin (p < 0.05). After in vitro digestion, the degree of protein hydrolysis of the digesta was higher for both larvae samples compared to beef loin (p < 0.05). No change was observed in the in vitro larval protein digestibility after defatting. These results highlight the excellent protein digestibility of P. brevitarsis larvae with high protein content. Defatting insect flour with 70% ethanol could enhance microbial safety while maintaining excellent protein digestibility.

• 한국발생생물학회지:발생과생식
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• 제25권1호
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• pp.33-41
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• 2021

This study was carried out to observe the development of the autonomous skeletal development of the Favonigobius gymnauchen. Total length (TL) of larvae 3 days after hatching (DAH) were mean TL of 3.34 mm, with a line-shaped parasphenoid ossification in the cranium and basioccipital ossification in the back. The 10 DAH larvae had a mean TL of 5.20 mm, with the number of caudal vertebrae increasing to 15. The urostyle and two hypural bones in the lower part also began to ossify. The 23 DAH juveniles had a mean TL of 8.47 mm. The pectoral girdle's skeleton was completed as the scapula and coracoid were ossified. The pelvic girdle also fully supported the ventral fin as its ossification was completed. Favonigobius gymnauchen and Tridentiger obscurus showed similar characteristics in terms of the anus location of hatched larvae, number of myotomes, and melanophore distribution during the morphological development of the larvae and juveniles. However, this study confirmed differences in the development of the vertebrae and urostyle bone.

• 대한의생명과학회지
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• 제12권2호
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• pp.99-104
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• 2006

Present study was performed to investigate the host-parasite relationship of the Korean Trichinella isolate (KTI). In the experiment to observe the infectivity of KTI to several kinds of animals, the reproductive capacity index (RCT) was highest in cats, and that in mice, hamsters and rats was followe4 in descending order. However, birds, i.e. wild goose and chicken, did not infect with KTI. The number of larvae per a gram of muscle (LPG: 377) was highest in the tongue of cats experimentally infected with KTI larvae. LPG in the diaphragm, anterior leg, back, posterior leg and abdominal muscles were 313, 246, 234, 225 and 170 respectively. Muscle larvae recovered at 55 days after infection were revealed the highest infectivity (RCI: 137.2) in mice. RCI was comparatively low in the mice infected with less than 25 day-old and more than 300 day-old larvae. In the experiment to observe the susceptibility of KTI by the mouse strain, ICR (RCI: 137.2), C57BL/6 (RCI: 108.8), DBA/2 (RCI: 107.1), C3H (RCI: 98.7), BALB/c (RCI: 96.9), FVB (RCI: 96.1) and B6C3F1 (RCI: 85.3) were very susceptible. However, BDF1 (RCI: 57.7) and CBA (RCI. 57.1) were revealed the moderate susceptibility, and B6CBAF1 (RCI: 23.1) was shown the lowest. The infection sites of adults were posteriorly transferred in the small intestine of experimental mice according to the infection periods of muscle larvae. The infection characteristics of KTI observed in this study may be useful as the basic data in the advanced studies, furthermore in the study of other Trichinella isolates.

• 환경생물
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• 제33권2호
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• pp.230-239
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• 2015

Monthly variations of cirriped larvae near Oryuk islets off Busan were investigated at four stations from January 2012 to January 2013. Zooplankton was vertically collected, using NORPAC net (mouth 45 cm, mesh $200{\mu}m$), from the surface to 1 m above the bottom. 12 species belong to five genera of 4 families were identified including one unidentified species. Cirriped larvae occupied small portion of total zooplankton, ranging 0.02 to 4.1% of total zooplankton densities. The densities varied monthly from $1inds.m^{-3}$ to $715.1inds.m^{-3}$, which was highest in September and lowest in February. Chthamalus challengeri, Balanus glanula, B. improbisus, B. nubilus and Octomeris sulcata were dominant species and accounted for 70.1% of total cirriped larvae. Larval densities of cirripeds between stations were not significantly different (F=0.237, p=0.870). The larval communities were grouped into two groups by cluster analysis. We discussed the distribution patterns of cirriped larvae in relation to oceanographic characteristics in the study area.

• 한국수산과학회지
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• 제37권6호
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• pp.478-484
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• 2004

On 11 June 1991, eggs from the brood stock of small yellow croaker (Larimichthys polyactis) were artificially fertilized using the standard dry method and were hatched. Each of the fertilized eggs (1.1-1.2 mm in diameter) had an oil globule and was transparent and buoyant. The fertilized eggs hatched in a range of water temperatures $(17.5-20.3^{\circ}C)$ 44 hrs after fertilization. The total lengths of the newly hatched larvae were 3.1-3.3 mm, and these hatchlings had 31 myotomes (10+21). Melanophores and yellow-brown chromatophores were concentrated on the head, at the ventral part of the yolk, and in the middle of the tail. Four days after hatching, the larvae completely absorbed the yolk and became flexions of 5.1-5.5 mm in total length. Fifteen days after hatching, one spine (the anterior tip of the maxillary) appeared in the upper jaw and three spines developed at the upper parts of the eyes and on the posterior part of the head. At this stage, the larvae were approximately 8.3 mm long. Thirty-nine days after hatching, juveniles (1.9-3.4 mm in total length) had a pointed tail fin. By 66 days after hatching, the juvenile fish (about 4.0-6.5 mm in total length) were similar to adult fish in body shape. The larvae of L. polyactis could be distinguished from those of L. croacea by two distinct characteristics: the large number of vertebrae (28-29), and a relatively small bony ridge on the occipital region of the head.

• 한국양봉학회지
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• 제33권4호
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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.

• 생태와환경
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• 제54권2호
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• pp.125-129
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• 2021

Chironomids are a large group of invertebrates that live in various aquatic habitats. The distribution range of these invertebrates has become varied due to anthropogenic impacts; as such, their distribution can be used as an indicator of environmental health. Adult chironomids are well known in South Korea; however, the larvae have rarely been studied due to difficulties associated with morphological classification. To address this lack of information, we collected larvae from four important rivers in South Korea and summarized their taxonomic morphological characteristics. The antennae, mandible, and mentum were used for larval taxonomic characterization. In this study, we describe the basic morphological features and key pictorial features of 20 species of chironomids, representing 16 genera.

• 한국수산과학회지
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• 제42권6호
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• pp.725-728
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• 2009

Four specimens of Cynoglossus larvae (3.2-7.3 mm in notochord length, NL) collected from the middle Yellow Sea in August, 2008 were identified as Cynoglossus joyneri larvae based on morphological characteristics; (1) the two elongated dorsal fin rays on the parietal region, (2) protruded abdomen, (3) no melanophores on the mediolateral trunk and tail. Larva of 3.2 mm NL is compressed with a little big head and tapering, long tail. Larva of 7.0 mm NL has 115 dorsal fin and 85 anal fin rays, which are the same to those of adult. Larva of 7.3 mm NL tended to have concave part in the fringe of forehead, in which left-side eye may move to the other side.

• 한국식품조리과학회지
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• 제31권5호
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• pp.534-543
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• 2015

Recently, the Tenebrio molitor larva was recognized as a novel food ingredient by the Ministry of Food and Drug Safety in Korea. Accordingly, we investigated its physical and sensory characteristics to establish the cooking conditions that may increase the demand of T. molitor larvae as a food. In this study, T. molitor larvae were cooked by various methods such as hot air dry, oven-broil, roast, pan fry, deep fry, boil, steam, and by microwave. In the physical evaluation of texture, the hardness and fracturability values were highest when larvae were cooked in the microwave. The adhesiveness, springiness, and chewiness values were highest when larvae were boiled. Boiled and steamed larvae had the highest lightness (L value), while oven-broiled larvae had the highest redness (a value) and yellowness (b value) values. Sensory evaluations assessed the appearance, aroma, flavor, and texture of cooked T. molitor larvae. Steamed and boiled larvae sizes were significantly large and the form was well preserved similar to fresh larvae. The moisture heat cooked (steamed and boiled) T. molitor larvae had the aroma and flavor of steamed corn, canned pupa, and boiled mushroom. In case of oven-broiled T. molitor larvae, the aroma and flavor of mealworm oil, seafood, sweet and roasted sesame were higher than in those cooked by other methods. In texture among sensory evaluation, the hardness and crispiness were the highest in the hot air dried and oven-broiled larvae, whereas juiciness was significantly higher in the boiled and steamed. Accordingly, we suggest that oven-broiled T. molitor larva will be prefered by consumer, due to its the rich aroma and flavor.