• 제목/요약/키워드: natural mortality

검색결과 378건 처리시간 0.036초

소하은어의 병소로부터 Flavobcterium succinicans의 분리 및 동정 (Isolation and identification of Flavobcterium succinicans from anadromous ayu Plecoglossus altivelis)

  • 이창훈;김필연;임봉수;오덕철;강봉조
    • 한국어병학회지
    • /
    • 제22권3호
    • /
    • pp.401-406
    • /
    • 2009
  • 2008년 5월 제주지역 하천에 소하하는 은어 중 일부개체가 주둥이 부식 또는 체표궤양증상을 보이면서 폐사하였다. 어류 질병원인균 중 부식증 및 체표궤양과 연관성이 높은 Flavobac-terium 속 세균의 분리를 위해 Shu-Shott medium 및 R2A medium에 주둥이 부식 및 체표궤양 부위를 도말하여 배양 하였고, Flavobacterium 속 세균의 전형적인 집락인 pale yellow colony를 분리하였다. 16S rDNA 염기서열 분석결과 Flavobacterium succinicans DSM 4002(Accession NO. AM230492)와 98.27%의 상동성을 보여 F. succinicans JMFL55로 동정하였다.

Reproductive Efficiency and Characteristics of Cloned Miniature Piglets Produced from Domestic Commercial Gilts

  • You, Jin-Young;Jeon, Yu-Byeol;Hyun, Sang-Hwan;Park, Soo-Bong;Lee, Eun-Song
    • 한국수정란이식학회지
    • /
    • 제25권4호
    • /
    • pp.215-219
    • /
    • 2010
  • The objective of this study was to examine the reproductive characteristics of cloned miniature piglets produced from surrogate domestic pigs. Somatic cell nuclear transfer (SCNT) miniature pig embryos were transferred into domestic pigs. As controls, domestic pigs of the same breed with surrogates for SCNT embryos and miniature pigs of the same breed with the somatic cell donor were bred by artificial insemination and natural mating, respectively. Surrogate domestic pigs that farrowed cloned miniature piglets had a significantly longer gestation length (118.1 days) than conventionally bred domestic (115.4 days) and miniature (115.5 days) pigs. Furthermore, the birth weight of cloned miniature piglets produced from domestic pigs (743 g) was significantly greater than that of miniature piglets produced by natural breeding (623 g). Also, cloned miniature piglets had a significantly lower weaning rate (49.7%) than conventionally produced domestic (91.5%) and miniature (100%) piglets. No differences were observed between female and male cloned piglets in gestation length, litter size, birth weight, or weaning rate. Our results demonstrate that gestation length is extended in domestic pigs that are transferred with SCNT miniature pig embryos and that cloned miniature piglets have increased birth weight and high pre-weaning mortality.

Termite Resistance of Impregnated Jabon Wood (Anthocephalus Cadamba Miq.) with Combined Impregnant Agents

  • Arsyad, Wa Ode Muliastuty;Basri, Efrida;Hendra, Djeni;Trisatya, Deazy Rachmi
    • Journal of the Korean Wood Science and Technology
    • /
    • 제47권4호
    • /
    • pp.451-458
    • /
    • 2019
  • Jabon (Anthocephalus cadamba Miq.) is a fast-growing species that exhibits a lower natural resistance than that exhibited by the timber sourced from natural forests. Jabon's resistance to termite attack can be improved by impregnating its wood structure with poisonous organic materials. This study examined jabon's resistance to termite attack when impregnated with wood vinegar and an animal adhesive. The wood specimens were impregnated using sengon wood vinegar and an animal adhesive (8% and 10%, respectively) using a vacuum pressure machine. The specimens were tested for their resistance to subterranean and dry-wood termites according to Indonesian National Standard (SNI 7207-2014). The results denoted that jabon impregnated with wood vinegar and an animal adhesive concentration of at least 8% with the addition of 4% borate was effective to resist termite attacks. The impregnated jabon exhibited a lower weight loss and higher termite mortality when compared with those exhibited by the control specimens. Thus, the resistance class improved from class IV to class I.

Nematicidal Compounds from the Leaves of Schinus terebinthifolius Against Root-knot Nematode, Meloidogyne incognita Infecting Tomato

  • Abdel Bar, Fatma M.;Ibrahim, Dina S.;Gedara, Sahar R.;Abdel-Raziq, Mohammed S.;Zaghloul, Ahmed M.
    • Natural Product Sciences
    • /
    • 제24권4호
    • /
    • pp.272-283
    • /
    • 2018
  • The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-${\alpha}$-L-rhamnoside (Afzelin) (2), quercetin-3-O-${\alpha}$-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-${\alpha}$-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of $200{\mu}g/mL$. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.

Infection Source and Epidemiology of Nontuberculous Mycobacterial Lung Disease

  • Jeon, Doosoo
    • Tuberculosis and Respiratory Diseases
    • /
    • 제82권2호
    • /
    • pp.94-101
    • /
    • 2019
  • Nontuberculous mycobacteria (NTM) are ubiquitous organisms that are generally found not only in the natural environment but also in the human engineered environment, including water, soil, and dust. These organisms can form biofilms and can be readily aerosolized because they are hydrophobic owing to the presence of the lipid-rich outer membrane. Aerosolization and subsequent inhalation were the major route of NTM lung disease. Water distribution systems and household plumbing are ideal habit for NTM and the main transmission route from natural water to household. NTM have been isolated from drinking water, faucets, pipelines, and water tanks. Studies that used genotyping have shown that NTM isolates from patients are identical to those in the environment, that is, from shower water, showerheads, tap water, and gardening soil. Humans are likely to be exposed to NTM in their homes through simple and daily activities, such as drinking, showering, or gardening. In addition to environmental factors, host factors play an important role in the development of NTM lung disease. The incidence and prevalence of NTM lung disease are increasing worldwide, and this disease is rapidly becoming a major public health problem. NTM lung disease is associated with substantially impaired quality of life, increased morbidity and mortality, and high medical costs. A more comprehensive understanding of the infection source and epidemiology of NTM is essential for the development of new strategies that can prevent and control NTM infection.

Quantification of the ichthyotoxic raphidophyte Chattonella marina complex by applying a droplet digital PCR

  • Juhee, Min;Kwang Young, Kim
    • ALGAE
    • /
    • 제37권4호
    • /
    • pp.281-291
    • /
    • 2022
  • Quantifying the abundance of Chattonella species is necessary to effectively manage the threats from ichthyotoxic raphidophytes, which can cause large-scale mortality of aquacultured fish in temperate waters. The identification and cell counting of Chattonella species have been conducted primarily on living cells without fixation by light microscopy because routine fixatives do not retain their morphological features. Species belonging to the Chattonella marina complex, including C. marina and C. marina var. ovata, had high genetic similarities and the lack of clear morphological delimitations between the species. To estimate the abundance of C. marina complex in marine plankton samples, we developed a protocol based on the droplet digital polymerase chain reaction (ddPCR) assay, with C. marina complex-specific primers targeting the internal transcribed spacer (ITS) region of the rDNA. Cell abundance of the C. marina complex can be determined using the ITS copy number per cell, ranging from 25 ± 1 for C. marina to 112 ± 7 for C. marina var. ovata. There were no significant differences in ITS copies estimated by the ddPCR assay between environmental DNA samples from various localities spiked with the same number of cells of culture strains. This approach can be employed to improve the monitoring efficiency of various marine protists and to support the implementation of management for harmful algal blooms, which are difficult to analyze using microscopy alone.

Simulation and validation of flash flood in the head-water catchments of the Geum river basin

  • Duong, Ngoc Tien;Kim, Jeong Bae;Bae, Deg-Hyo
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2021년도 학술발표회
    • /
    • pp.138-138
    • /
    • 2021
  • Flash floods are one of the types of natural hazards which has severe consequences. Flash floods cause high mortality, about 5,000 deaths a year worldwide. Flash floods usually occur in mountainous areas in conditions where the soil is highly saturated and also when heavy rainfall happens in a short period of time. The magnitude of a flash flood depends on several natural and human factors, including: rainfall duration and intensity, antecedent soil moisture conditions, land cover, soil type, watershed characteristics, land use. Among these rainfall intensity and antecedent soil moisture, play the most important roles, respectively. Flash Flood Guidance is the amount of rainfall of a given duration over a small stream basin needed to create minor flooding (bank-full) conditions at the outlet of the stream basin. In this study, the Sejong University Rainfall-Runoff model (SURR model) was used to calculate soil moisture along with FFG in order to identify flash flood events for the Geum basin. The division of Geum river basin led to 177 head-water catchments, with an average of 38 km2. the soil moisture of head-water catchments is considered the same as sub-basin. The study has measured the threshold of flash flood generation by GIUH method. Finally, the flash flood events were used for verification of FFG. The results of the validation of seven past independent events of flash flood events are very satisfying.

  • PDF

USCG Phase II 선박평형수 성능 평가를 위한 해양 식물플랑크톤군집 대량 확보 및 생물사멸시험 (Viability Test and Bulk Harvest of Marine Phytoplankton Communities to Verify the Efficacy of a Ship's Ballast Water Management System Based on USCG Phase II)

  • 현봉길;백승호;이우진;신경순
    • 해양환경안전학회지
    • /
    • 제22권5호
    • /
    • pp.483-489
    • /
    • 2016
  • 본 연구는 USCG phase-II의 형식승인 기준인 자연상태 생물군집의 75 % 이상 유지하여야 하는 평가체계에 대비하여 자연생물군집 농축 및 선박평형수관리시스템(Ballast Water Management System, BWMS) 처리 전 후 생물사멸시험을 실시하였다. 자연 식물플랑크톤군집의 농축 조사는 중영양수계인 장목만과 부영양화수계의 마산만에서 동계에 수행하였다. 장목만과 마산만에서 1톤 기준으로 생물을 농축하였을 경우, $10-50{\mu}m$ 크기 생물 현존량은 $4.7{\times}10^4cells\;mL^{-1}$$0.8{\times}10^4cells\;mL^{-1}$ 이었고, 농축생물의 생존율은 90.4 %와 88.0 %로 각각 나타났다. 특히 장목만에서는 Skeletonema costatum-like species 같은 체인을 형성하는 소형 규조류가 극우점한 반면, 마산만에서는 $<10{\mu}m$보다 작은 편모조류 및 체인을 형성하지 않는 대형 와편모조류(Akashiwo sanguinea, Heterocapsa triquetra)가 우점하였다. 이와 같은 우점종 세포크기의 차이로 장목만 농축효율이 마산만보다 높게 나타났다. BWMS 장비를 통과한 처리 당일 생물 사멸률은 장목만이 90.4 %로, 마산만의 93 %보다 약간 낮았고, 장목만에서 BWMS 처리 5일 경과 후, 대조군의 대상생물의 사멸률은 6.7 %로 나타났다. 처리군에서는 >99 %로 대부분 사멸되어, 시험생물로서의 적용 가능성을 확인할 수 있었다. 결과적으로 동계와 같이 해역내 생물량이 낮을 경우, 주간 8시간 수행한 네트의 생물농축만으로 는 USCG Phase II의 형식승인 기준인 500톤 탱크에 $1.0{\times}10^3cells\;mL^{-1}$ 이상으로 자연생물 개체수 밀도를 충족하기는 쉽지 않다는 것을 파악하였고, 이를 보완하기 위해서는 일정기간 자연생물을 대량 배양 및 채집할 수 있는 시스템 도입이 필요할 것으로 판단된다.

Toxicity Studies on Peristrophe paniculata (Forssk) Brummitt;an Ayurveda Drug

  • Pradeep Chandran, R.V.;Saraswathy, A.;Manohar, B. Murali;Vairamuthu, S.
    • Natural Product Sciences
    • /
    • 제14권2호
    • /
    • pp.122-126
    • /
    • 2008
  • Chronic oral toxicity studies (90 days) on aqueous and methanol extracts of the whole plant of Peristrophe paniculata (Forssk) Brummitt were carried out in Wistar rats. The dosage was 200 mg/kg/day, p.o. for both the extracts. All external morphological and biochemical changes, in addition to body weight and vital organ weights were recorded. During this investigation, no significant mortality was observed. The results showed that both the extracts were devoid of any toxicity at the dose level studied as compared to the control group.

비파열 뇌동맥류의 치료-자연경과 및 수술적 치료결과 (Management of Unruptured Intracranial Aneurysms-Natural Course & Surgical Outcomes)

  • 안재성;권병덕
    • Journal of Korean Neurosurgical Society
    • /
    • 제30권6호
    • /
    • pp.813-818
    • /
    • 2001
  • Objectives : The best results of treating intracranial aneurysms can be achieved with treating aneurysm before they rupture. Some recent reports about the risk of the bleeding of the unruptured intracranial aneurysm(UIA) being too low(0.05% per year) compared with 1~2% of the previously reported bleeding probability, casts the question about the need for treatment of the UIAs. The purpose of this report is to review the recent reports about the risk of rupture of the UIAs and to assess the morbidity and mortality associated with surgical treatment for UIAs.

  • PDF