• Title/Summary/Keyword: brood

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Growth Performance of Offspring from Selected and Non-Selected Brood Line of Red Sea Bream, Pagrus major

  • Noh, Choong-Hwan;Hong, Kyung-Pyo;Myoung, Jung-Goo;Kim, Jong-Man
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.36-36
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    • 2003
  • In the present study, growth performances of the offspring from selected brood line were compared to those of the offspring from non-selected brood line of red sea bream. Offspring groups were mass produced separately from two brood lines, selected and non-selected Korean strain. Selected brood line have been selected by fish size for four generations (upper 5∼30% per generation) and non-selected brood line is the second generation of wild population at south sea in Korea. There's no significant difference in body length between offspring from selected and non-selected brood line during early growing stage (until 96-days old). However, offspring from selected brood line had superior body weight growth than offspring from non-selected brood line. At sea cages rearing trials with communal stocking, Offspring from selected brood line showed significantly better performance in body weight, body length, weight gain, specific growth rate and feed consumption (but not in feed conversion ratio) than offspring from non-selected brood line. At 24 months old, offspring from selected brood line grew faster 1.10 times in body length and 1.41 times in body weight than offspring from non selected brood line. The response to selection when compared to a non-selected line is on average of 10% in weight per generation at 24 months old.

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Habitat selection in the lesser cuckoo, an avian brood parasite breeding on Jeju Island, Korea

  • Yun, Seongho;Lee, Jin-Won;Yoo, Jeong-Chil
    • Journal of Ecology and Environment
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    • v.44 no.2
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    • pp.106-114
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    • 2020
  • Background: Determining patterns of habitat use is key to understanding of animal ecology. Approximately 1% of bird species use brood parasitism for their breeding strategy, in which they exploit other species' (hosts) parental care by laying eggs in their nests. Brood parasitism may complicate the habitat requirement of brood parasites because they need habitats that support both their host and their own conditions for breeding. Brood parasitism, through changes in reproductive roles of sex or individual, may further diversify habitat use patterns among individuals. However, patterns of habitat use in avian brood parasites have rarely been characterized. In this study, we categorized the habitat preference of a population of brood parasitic lesser cuckoos (Cuculus poliocephalus) breeding on Jeju Island, Korea. By using compositional analyses together with radio-tracking and land cover data, we determined patterns of habitat use and their sexual and diurnal differences. Results: We found that the lesser cuckoo had a relatively large home range and its overall habitat composition (the second-order selection) was similar to those of the study area; open areas such as the field and grassland habitats accounted for 80% of the home range. Nonetheless, their habitat, comprised of 2.54 different habitats per hectare, could be characterized as a mosaic. We also found sexual differences in habitat composition and selection in the core-use area of home ranges (third-order selection). In particular, the forest habitat was preferentially utilized by females, while underutilized by males. However, there was no diurnal change in the pattern of habitat use. Both sexes preferred field habitats at the second-order selection. At the third-order selection, males preferred field habitats followed by grasslands and females preferred grasslands followed by forest habitats. Conclusions: We suggest that the field and grassland habitats represent the two most important areas for the lesser cuckoo on Jeju Island. Nevertheless, this study shows that habitat preference may differ between sexes, likely due to differences in sex roles, sex-based energy demands, and potential sexual conflict.

Honey bees and their brood: a potentially valuable resource of food, worthy of greater appreciation and scientific attention

  • Ghosh, Sampat;Meyer-Rochow, Victor Benno;Jung, Chuleui
    • Journal of Ecology and Environment
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    • v.45 no.4
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    • pp.293-304
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    • 2021
  • Despite the consumption of bee brood in several parts of the world, particularly in the tropical areas, the practice has received comparatively little attention. We have reviewed all the available information on the nutrient composition and functional properties of different developmental stages of honey bee workers belonging to different species and subspecies. Noticing the competent nutrient composition of, in particular, honey bee brood, pupae, and prepupae, we suggest that they could be a potential source of human nutrition as well as animal feed. Moreover, drone brood is an ideal candidate for use as a food or as food ingredient. However, to analyze the functional properties of different honey bee species remains a task for further analysis.

Reproductive Ecology of the Freshwater Melania Snail, Semisulcospira coreana (v. Martens) in Bukhan River (북한강 참다슬기, Semisulcospira coreana (v. Martens) 의 번식생태)

  • Kim, Dae-Hee;Bang, In-Chul;Lee, Wan-Ok;Baek, Jae-Min
    • The Korean Journal of Malacology
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    • v.28 no.2
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    • pp.175-185
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    • 2012
  • To clarify reproductive ecology of the melania snail Semisulcospira coreana (v. Martens, 1886) in Bukhan River, gonad development, fatness, gonad index, sex ratio, first sexual maturity of population, monthly change of larvae number and developmental stages in brood pouches were investigated by six identification methods. As maturation progrsses, the sex of the snali can be distinguishable easily by color:: the ovary being blue-green and testis light yellow. The sex ratio of female to male individuals over 13.95 mm shell height was significantly different from 1:1 (${\chi}^2$ = 38.45, p < 0.05). The sex ratio of female to male individuals changed drastically according to the season, Based on the monthly variations of fatness, gonad index and histological analysis, spawning occurred twice a year (spring and autumn) and the mean size of matured eggs was $450{\mu}m$ in diameter. The monthly change of larval number in brood pouch showed also two distinct peaks in March and September during the year. The average number of larvae in brood pouches was 286 - 862 individuals. In this study, the number of larvae in the brood pouches were a minimum in December and a maximum in March (975 larvae). The biological minimum size (the size at 50% of group sexual maturity) of the melania snail was 13.95 mm in shell height in females and males. All females over 15 mm in shell height possesed brood pouches.

Breeding Behavior of Black Vulture In Erdenesant, Mongolia (몽골 Erdenesant 지역의 독수리 번식행동)

  • Paek, Woon-Kee;Batbayar, Nyambayar;Chun, Byung-Sun;Natsagdorj, Tseveenmyadag;Yu, Jae-Pyoung;Paik, In-Hwan;Lee, Han-Soo
    • Proceedings of the Korean Society of Environment and Ecology Conference
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    • 2006.10a
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    • pp.98-102
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    • 2006
  • We studied the behavior of black vultures breeding in Erdenesant, Mongolia through time budget observation. We observed a pair of black vulture for 115 days from April 30 to August 22, 2005, of which 15 days were before hatching and 100 days of brood rearing. The egg hatched on May $14^{th}$. Incubation was done by both a male and female vultures, but the period covered by the male vulture(56.82%) was longer than that by the female one(34.62%). In the early days of brood rearing, time spent by the female vulture at the nest took 54.9 % and it was 19.27% for the male. In the middle of brood rearing period, just inaction and preening were noticed, as they watched their chicks for a long time without sheltering chick under the parent's body. Late brood rearing period was characterized by less chick care and adults mostly stayed in the nest only when to feed the chicks. During breeding time, both the male and the female vulture fed only the chicks and did not give food to each other. During rearing period, the male vulture fed the chick more often than female.

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Increasing Production in Korean Shrimp Farms with White-Spot Syndrome Virus PCR-Negative Brood Stock

  • Seok, Seung-Hyeok;Baek, Min-Won;Lee, Hui-Young;Kim, Dong-Jae;Chun, Myung-Sun;Kim, Jong-Sheek;Chang, Se-Ok;Park, Jae-Hak
    • Journal of Microbiology and Biotechnology
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    • v.17 no.3
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    • pp.511-515
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    • 2007
  • White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSSV-PCR-negative fly epidemiologically decreases white-spot disease outbreaks. Here, we report a retrospective analysis of data from shrimp farms in the western coast of Korea where WSSV-PCR-negative brood stocks were used to stock rearing ponds. A total of 366 shrimp from Heuksan Island were sampled for WSSV with PCR. Of the tested shrimp, 7.2% (28 brood stocks) were identified as WSSV positive; only WSSV-PCR-negative shrimp were used for brood stocks. Total unit production (final shrimp production/ the area of the ponds) was higher, at 1.96, in ponds where WSSV-PCR-negative shrimp were used, as compared with 1.02 in other ponds in Korea in 2004. This retrospective analysis of WSSV in Korea may be useful to the shrimp aquaculture industry, suggesting a testable hypothesis that may contribute to the eventual control of WSSV outbreaks.

Effects of Temperature and Salinity on Productivity and Growth of Five Copepod Species (수온과 염분에 따른 5종 요각류의 성장과 생산력)

  • LEE Kyun Woo;PARK Heum Gi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.38 no.1
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    • pp.12-19
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    • 2005
  • This study investigated the productivity and growth of copepods, Sinocalanus tenellus 2 strains, Paracyclopina nana 3 strains, Apocyclops royi 2 strains, Tachidius triangularis 1 strain and Tigriopus sp. 1 strain at different temperatures $(24,\;28\;and\;32^{\circ}C)$ under 15 psu and various salinities (10, 20, 30 psu) at $28^{\circ}C$ for an individual culture. And the mass culture was carried out to evaluate the production of these copepods in the 500 mL vessel. For an individual culture of copepod, survival period of a brood female tended to increase with the decrease of temperature, but was not significantly influenced by salinity. With an increase of temperature and a decrease of salinity, maturation period of nauplii in all species tended to decrease. Total nauglii production from a broodo female at $24^{\circ}C$ was higoher than that from a brood .female at either 28 or $32^{\circ}C$ for S. tenellus and at $32^{\circ}C$ than either 24 or $32^{\circ}C$ for A. royi Haenam stram, but was not influenced by temperature for another copepods. And total nauplii production from a brood female at 10 and 20 psu tended to be higher than that from a brood female at 30 psu, expect for Tigriopus sp. and P. nana Hwajinpo strain. Total nauplii production from a brood female was the highest in Tigriopus sp. (350 nauplii) at $28^{\circ}C$ under 20 psu, followed by A. royi Haenam strain (187 nauplii) at $32^{\circ}C$ under 15 psu and P. nana Hwajinpo strain (152 nauplii) at $24^{\circ}C$ under 10 psu. In the mass culture of each copepod, P. nana was the most productive (26.6 mg dry weight) and this value was two and four times higher than productivity of Tigriopus sp. and A. royi, respectively.

Reproductive Pattern of the Epifaunal Amphipod Pontogeneia rostrata (Crustacea) on Dolsando Sandy Shore in Korea

  • Yu, Ok-Hwan;Jeong, Seung-Jin;Suh, Hae-Lip
    • Ocean Science Journal
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    • v.43 no.3
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    • pp.127-133
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    • 2008
  • Reproductive patterns of an epifaunal amphipod, Pontogeneia rostrata, were studied on Dolsando sandy shore in Korea. The life history pattern was iteroparous, with recruitment mainly occurring from winter to spring. The sex ratio was malebiased, especially during breeding periods. The mean body length of females was significantly larger than that of males. Brood size and egg volume were positively related to the body length of ovigerous females. There was no significant difference in brood size between successive breeding periods, but egg volumes were significantly higher in early winter (December) than in late spring breeding (May and June), increasing the probability of survival to hatching. These traits contribute to more reproductive potential in early winter than in late spring breeding. The mean brood size of epifaunal P. rostrata was larger but the mean egg volume smaller than that of infaunal amphipods in this sampling area. We suggest that reproductive effort for epifaunal species may be proportionally greater than for infaunal species in risky environments.

The Screening of Marine Birnavirus (MABV) Infected in Brood Stocks of Flounder, Paralichthys olivaceus (친어용 넙치 성어에 있어 Marine Birnavirus (MABV) 감염에 관한 검색)

  • Oh, Myung-Joo;Jung, Sung-Ju;Kim, Young-Jin;Kim, Hyeung-Rak;Jung, Tae-Sung;Yeo, In-Kyu
    • Journal of fish pathology
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    • v.13 no.1
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    • pp.53-59
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    • 2000
  • Presence of marine birnavirus (MABV) was examined against egg and ovarian fluid, and seminal fluid from the brood stocks of flounder, Paralichthys olivaceus collected from 9 different stations around Korean peninsula. The detection rate of MABV in brood stocks flounder was observed to 34% by PCR. The mean virus titer of the PCR positive fish was $10^{2.30}$ to $10^{4.30}$ $TCID_{50}$/g(ml). By a neutralization test, all of the isolated virus were ascertained to be closely related to marine birnavirus (MABV).

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