• Journal of Aquaculture
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• v.13 no.4
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• pp.285-293
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• 2000

Mortality suffered by the sea squirt in indoor experiment was higher at the stocking density of 12 kg than that at 3 and 6 kg. Daily mortality was also higher at 8 t:: thermal fluctuation than that at 3 and 5$^{\circ}C$. The thermal fluctuation observed at the depth of 5 m during June was higher, i.e. 7.4$^{\circ}C$ but it was just 2-4$^{\circ}C$ during mid-May. It did not fluctuate at all during the period from January to February. Mortality was higher at the stocking density of 12 kg during June than at 10 and 15 m depth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.69-73
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• 1976

Mortality of clam, Meretrix lusoria was measured during the experimental cultures in different sediments compositions and in different salinities of sea water. Experimental groups maintained in silt and clay showed significant mortality, while those treated in sand and in sand-silt showed little mortality. In the groups cultured in silt and clay, young groups of approximately 2.5cm in shell length were subjected to early and high mortality (approximately eighty-five per cent in foully-one days). The larger the shell size was, the later and the lower the mortality occurred. In different salinity, the groups maintained in silt and clay showed different mortalities. It is observed that the survival rate of the shell in the sea water of low salinity was higher than that in the high salinity water. Oxygen consumption of isolated gill tissue showed a little difference between the groups maintained in silt and clay and those in sand (the control-group). Consequently, it may be stated that the mortality results mainly from the deposition of silt and clay, although the survival rate of Meretrix lusoria depends also on water temperature, salinity, dissolved oxygen, body size ana other factors.

• Journal of fish pathology
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• v.32 no.1
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• pp.29-35
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• 2019

A monitoring was performed to survey the mortalities that had occurred in the aquaculture farms of olive flounder (Paralichthys olivaceus) in South Korea from 2015 to 2017. The indirect inquiry for entire farms and the sample survey for selected farms were carried out. The aquatic organism disease inspectors, who have a national license for the diagnosis and prevention of aquatic organism diseases and a have close relationship with the farms, investigated the rates and causes of mortalities according to the standard manual. The mortality rate by sample survey of farms in 2015, 2016, and 2017 were 24.78% (Chunnam: 17.86%, Jeju: 28.69), 30.19% (Chunnam: 24.45%, Jeju: 32.65), and 21.59% (Chunnam: 10.57%, Jeju: 26.00%), respectively. The major cause of mortality was scuticociliatosis, and the mortality caused by viral hemorrhagic septicemia and emaciation disease (Jeju) were also high. Our results can contribute to effective establishment prevention of epidemics system and acquired status as a disease-cleansing country.

• KOREAN POULTRY JOURNAL
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• v.4 no.6 s.32
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• pp.88-89
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• 1972

무제한 급수하면 저에너지 사료를 섭취하는 닭은 모자란 에너지의 보충을 위해 사료를 더 많이 섭취하여 에너지의 제한 효과가거의 없었고 제한급수하면 사료를 충분히 섭취할 수 없기 때문에 대조구의 약 70$\%$밖에 섭취못했다. 따라서 이것이 성성숙을 4$\~$4 1/2주 지연시킨 요인이었으며 체지방 축적도 감소시켰다. 성성숙 지연결과 성숙이 지연된 닭은 총 산란수가 훨씬 많고 비정상란의 수가 훨씬 적으며 대란율도 훨씬 높다. 육성중 폐사율은 더운 여름철에도 급수의 제한과 상관없었으며 산란중 폐사율은 오히려 성성숙시의 체중 혹은 체지방 축적과 정비례 했다. 이상으로 저에너지 사료를 급여하면서 급수제한(격일제 급수)하는 방법이 대추의 에너지 섭취를 제한시키는 간단하고 효과적인 방법임이 입증되었다.

• The Korea Swine Journal
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• v.29 no.11 s.339
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• pp.184-188
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• 2007

시장 개방의 가속화로 어려움이 한층 가중되고 있는 요즘 한.미 자유무역협정(FTA) 협상 타결에 이어 유럽연합(EU)과의 FTA 협상이 진행 중이다. 이처럼 거센 시장 개방 환경에서 살아남으려면 우리 양돈산업의 경쟁력 향상이 절대적으로 요구된다. 이를 위해서는 철저한 사양관리와 환기관리를 통한 폐사율의 감소와 생산성 향상은 우리 농가들에게 필수적으로 요구되고 있는 항목이다. 저온진입기, 즉 동절기로 진입하는 요즘에는 보온으로 인한 환기불량과 추위로 인한 생체기능이 떨어지기 때문에 전반적인 질병에 대한 저항력이 감소되어 질병 발생 가능성은 어느 계절보다 크다. 양돈농가의 생산성 저하로 인한 경제적 피해를 최소하화기 위해서는 돼지의 호흡기질병 예방을 철저히 하고 농장의 단열과 환기시설 점검을 통한 효율적인 대책에 만전을 기해야 성공적인 양돈을 기대 할 수 있을 것이다. 높은 폐사율을 극복하고 부족한 환기관리와 시설은 꼼꼼한 컨설팅으로 보완하여 생산성 향상에 노력하고 있는 충남 당진 순성농장(대표 박중호)을 찾아가 보았다.

• Feed Journal
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• v.5 no.4 s.44
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• pp.142-145
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• 2007

• 농업기술회보
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• v.50 no.2
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• pp.26-27
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• 2013

우리나라의 2010년 연간 모돈 당 비육돈 출하두수는 16.5두로 양돈 선진국인 네덜란드 24.7두의 67% 수준으로 매우 낮다. 이는 산자수가 낮고 이유 후 폐사율이 높기 때문이다. 생산성을 높이기 위한 항생제 사용도 2011년 7월부터 전면 금지되었기에 농촌진흥청에서는 이유 후 새끼돼지의 폐사율을 줄일 수 있도록 어미돼지의 유질을 개선할 수 있는 항생제 대체물질 목단피 추출물 사료첨가제를 개발하였다.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.37-42
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• 2006

The current study was conducted to investigate the effect of types of crate and season on transport condition and mortality, and ultimately to identify the best practice for reducing economic lose. Total loading weight stocking density, transport and lairage times and mortality were surveyed from the management data sheet of two companies for each first week of January, April, August and October, An average loading weight, length of transport and lairage times and mortality were 3.9 ton, 96 min, 478 min and 0.6%, respectively. Mortality after lairage was not significant between two types of crate. In addition, container type crate showed higher loading weight and stocking density than box type one. Spring and winter had significantly higher mortality with 0.7 and 0.8%, respectively, then summer and fell of 0.5%. An interaction between crate type and season on mortality showed that mortality for box type on was higher in spring and winter with 0.8 and 0.7%, respectively, compared to summer and fall of 0,3 and 0.4% respectively. In the case of container type crate, spring, fall and winter had greatly different death into with 0.7, 0.5 and 0.8%, respectively, while there was no difference between spring and summer, and between summer and winter, Mortality after transportation was similar between both crate type, with higher rate for spring and winder than other seasons. The result was likely related to death of exposure due to extended waiting time without heating facility.

• Journal of Aquaculture
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• v.5 no.2
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• pp.177-182
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• 1992

Experiments were conducted with goldfish exposed to various levels of mercuric chloride(control group) and mercuric chloride with chitosan (experimental group). Dilutions of these two solutions were made in the concentration ranges 0.6 to 1.0 $mg/{\ell}$ and 1.2 to 2.0 $mg/{\ell}$, respectively. Fifty percent lethal concentration of mercuric chloride($LC_{50}$) for 48 hours with the species was between 0.6 and 0.7 $mg/{\ell}$. Exposure of goldfish to mercury produced a marked, dose-dependent mortality with elevation of concentration (P<0.05). However, at each concentration of mercuric chloride treated with chitosan, mortality decreased significantly compared to control group (P<0.05).

• Journal of fish pathology
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• v.19 no.2
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• pp.87-97
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• 2006

In previous study, scuticociliate P. dicentrachi was isolated from farmed flounder during the december 2004 to april 2005. Pathogenicity, mortality and infection symptom were studied using 3 cm and 5 cm groups of juvenile flounder. The ciliates were exponentially increased from bottom layer of the experimental tanks, which propagated within 2000 cells/ml (1.4 × 103 cell ㎖-1 ～ 2.5 × 103 cell ㎖-1) after 6 days of inoculation. The middle layer was maintained within 300 cells/ml. Both 3 cm and 5 cm groups were infected with ciliates, mainly 3 cm group showed high mortality during the experimental period. The death of 3 cm group was started from 5 days and showed 95.6% of mortality after 28 days of first inoculation. The control group showed 4.4% of mortality however, we could not observed any ciliates. The death of 5 cm group was started later than 3 cm group after 18 days of first inoculation. The total mortality was 71% during 28 days. No mortality and infection symptoms were observed in the control. We also studied SSU rRNA gene of ciliates which, re-isolated from infected flounder of experimental groups. When SSU rRNA in this study compared with previous data showed that the identified strain of both previous and present study was same.