• Title/Summary/Keyword: Fish population

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Infection with Opisthorchis viverrini and Use of Praziquantel among a Working-age Population in Northeast Thailand

  • Saengsawang, Phubet;Promthet, Supannee;Bradshaw, Peter
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2963-2966
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    • 2013
  • Infection with Opisthorchis viverrini (OV) due to eating certain traditional freshwater fish dishes is the principal risk factor for cholangiocarcinoma in Northeast Thailand where the infection is endemic and the incidence of this form of primary liver cancer has been the highest in the world. This paper is the second report of a prospective research project to monitor the impacts of a national liver fluke control programme in a rural community of Northeast Thailand. A sample of 684 villagers aged 20-65 years completed an interview questionnaire and were tested for infection using the Kato thick smear technique. The questionnaire was designed for the exploration of associations between OV infection, previous treatment with praziquantel, and knowledge and beliefs about the drug. The data were analysed using descriptive statistics and multiple logistic regression. The overall prevalence of OV infection was 37.2% and was highest in the 20-35 year age group, in those with a university degree and in those employed in the government sector. As many as 91.8% reported eating fish dishes known to place them at risk of infection. In the multiple regression analysis, previous use of praziquantel and lack of knowledge about whether or not the drug has a protective effect against re-infection were the only factors related to OV infection ($OR_{adj}$= 2.31, 95%CI =1.40-3.79 and $OR_{adj}$= 1.95, 95%CI= 1.24-3.05). The findings were discussed in terms of the possibly unwise dependency on praziquantel as a primary element in a control programme.

Ecology and Early Life History of Endangered Freshwater Fish, Pseudobagrus brevicorpus (Pisces: Bagridae) (꼬치동자개(Pseudobagrus brevicorpus)의 생태와 초기 생활사)

  • Kang, Eon-Jong;Yang, Hyun;Lee, Heung-Heon;Cho, Yong-Cheol;Kim, Eung-Oh;Lim, Sang-Gu;Bang, In-Chul
    • Korean Journal of Environmental Biology
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    • v.25 no.4
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    • pp.378-384
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    • 2007
  • Some of ecological factors and the early life history of endangered freshwater fish, Pseusobagrus brevicorpus, were investigated to proliferate artificially and to restore the population by release seedlings. The density of population in restricted area by small scale dam was 1.25 ind. $m^{-2}$, and the low capacity for reproduction having 200$\sim$250 eggs ind$^{-1}$. were thought to be a reason of this endangered situation. From the result of induction of natural spawning in aquarium after hormone injection it was considered that the spawning substrate would be aquatic plants with slender branches. The hatching was observed after 50 hrs after fertilization and the larvae showed aggressive behavior. Yolk was almost absorbed 3 days after hatching, and the larvae shaped tad-pole grew up to fry after 30 days. We discussed on the strategies for conservation of this species according to those results from investigation on ecology and early life history.

APPROXIMATE ESTIMATION OF RECRUITMENT IN FISH POPULATION UTILIZING STOCK DENSITY AND CATCH (밀도지수와 어획량으로서 수산자원의 가입량을 근사적으로 추정하는 방법)

  • KIM Kee Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.8 no.2
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    • pp.47-60
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    • 1975
  • For the calculation of population parameter and estimation of recruitment of a fish population, an application of multiple regression method was used with some statistical inferences. Then, the differences between the calculated values and the true parameters were discussed. In addition, this method criticized by applying it to the statistical data of a population of bigeye tuna, Thunnus obesus of the Indian Ocean. The method was also applied to the available data of a population of Pacific saury, Cololabis saira, to estimate its recuitments. A stock at t year and t+1 year is, $N_{0,\;t+1}=N_{0,\;t}(1-m_t)-C_t+R_{t+1}$ where $N_0$ is the initial number of fish in a given year; C, number o: fish caught; R, number of recruitment; and M, rate of natural mortality. The foregoing equation is $$\phi_{t+1}=\frac{(1-\varrho^{-z}{t+1})Z_t}{(1-\varrho^{-z}t)Z_{t+1}}-\frac{1-\varrho^{-z}t+1}{Z_{t+1}}\phi_t-a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}C_t+a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}R_{t+1}......(1)$$ where $\phi$ is CPUE; a', CPUE $(\phi)$ to average stock $(\bar{N})$ in number; Z, total mortality coefficient; and M, natural mortality coefficient. In the equation (1) , the term $(1-\varrho^{-z}t+1)/Z_{t+1}$s almost constant to the variation of effort (X) there fore coefficients $\phi$ and $C_t$, can be calculated, when R is a constant, by applying the method of multiple regression, where $\phi_{t+1}$ is a dependent variable; $\phi_t$ and $C_t$ are independent variables. The values of Mand a' are calculated from the coefficients of $\phi_t$ and $C_t$; and total mortality coefficient (Z), where Z is a'X+M. By substituting M, a', $Z_t$, and $Z_{t+1}$ to the equation (1) recruitment $(R_{t+1})$ can be calculated. In this precess $\phi$ can be substituted by index of stock in number (N'). This operational procedures of the method of multiple regression can be applicable to the data which satisfy the above assumptions, even though the data were collected from any chosen year with similar recruitments, though it were not collected from the consecutive years. Under the condition of varying effort the data with such variation can be treated effectively by this method. The calculated values of M and a' include some deviation from the population parameters. Therefore, the estimated recruitment (R) is a relative value instead of all absolute one. This method of multiple regression is also applicable to the stock density and yield in weight instead of in number. For the data of the bigeye tuna of the Indian Ocean, the values of estimated recruitment (R) calculated from the parameter which is obtained by the present multiple regression method is proportional with an identical fluctuation pattern to the values of those derived from the parameters M and a', which were calculated by Suda (1970) for the same data. Estimated recruitments of Pacific saury of the eastern coast of Korea were calculated by the present multiple regression method. Not only spring recruitment $(1965\~1974)$ but also fall recruitment $(1964\~1973)$ was found to fluctuate in accordance with the fluctuations of stock densities (CPUE) of the same spring and fall, respectively.

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A Survey on Fish Habitat Conditions of Domestic Rivers and Construction of Its Database (국내 어류 서식환경 조사 및 데이터베이스 구축)

  • Jung, Jin-Hong;Park, Ji-Young;Yoon, Young-Han;Lim, Hyun-Man;Kim, Weon-Jae
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.3
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    • pp.221-230
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    • 2014
  • In order to restore an ecologically damaged river, freshwater fish which inhabit at the target aquatic ecosystem have a great applicability as one of the essential indicators. Although the informations about the habitat conditions of freshwater fish are key elements reflecting biological, physical, and chemical properties of the aquatic environment, because of the lack of preceding related research and insufficient database with scattered data, they have not been applied effectively for the ecological river restoration projects in Korea. To cope with these problems, based on the nation-wide detailed investigation for domestic freshwater fish habitat conditions, we have selected 70 species considering the possibility for the candidates of flagship species, constructed a database for their population, physical, and chemical habitat properties, and suggested its application methodology for the river restoration projects. In particular, the utilization of the database has been enhanced by the additional statistical analysis to present their resistance and optimum ranges for physical, and chemical habitat properties respectively. It is expected that the database constructed in this study can be utilized for the calculation and evaluation of the appropriate ecological flow rate and target water quality for the selected flagship species (fish), and the basic data for the restoration of river environment.

Density Effect and Diversity of Fish in Water System at Both Reservoirs in the Youngsan-ri, Goseong-gun (고성군 용산리의 두 저수 수계에서 어류의 다양성과 밀도 효과)

  • Huh, Man Kyu;Choi, Byoung-Ki
    • Journal of Life Science
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    • v.25 no.5
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    • pp.533-538
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    • 2015
  • Four sites and one site were used to analyze fish diversity at the water systems of the Sineun reservoir and the Jeonchon reservoir, respectively. The field experiments were conducted to test the density dependence that could lead to population regulation by artificial inferences and environmental changes. We examined the effects of environmental factors on fish densities using SMATR freeware. It was estimated to be reduced to the density effect at four sites in 2012. Shannon-Weaver indices of the diversity (H’) of the Sineun reservoir were similar to those of the Jeonchon reservoir. Species diversity was in a range of 0.645 to 2.105. The H’ value of the upper region was higher than those of middle and low regions were, and values of richness were lower in downstream than upstream. Using the maximum likelihood solution for the removal estimators of two low regions of the river stations, the estimated migration probabilities from the resident fish to the migrated fish for five species (Cyprinus cuvieri, Carassius auratus, Pseudorasbora parva, Misgurnus mizolepis, and Oryzias latipes) had a mean of 0.623. Especially, migration probabilities from the Jeonchon reservoir to the Sineun reservoir for five species were high (a mean of 0.681). The period of migration was suggested to be about one month because of short geographical distances (50 m). We found no significant difference between the three categories in the distribution of the other four species, indicating the species probability was similar among stations.

Dietary Patterns and Risk of Colorectal Cancer: A Systematic Review of Cohort Studies (2000-2011)

  • Yusof, Afzaninawati Suria;Isa, Zaleha Md.;Shah, Shamsul Azhar
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4713-4717
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    • 2012
  • Objectives: This systematic review of cohort studies aimed to identify any association between specific dietary patterns and risk of colorectal cancer (CRC). Dietary patterns involve complex interactions of food and nutrients summarizing the total diet or key aspects of the diet for a population under study. Methods and materials: This review involves 6 cohort studies of dietary patterns and their association with colorectal cancer. An exploratory or a posteriori approach and a hypothesis-oriented or a priori approach were employed to identify dietary patterns. Results: The dietary pattern identified to be protective against CRC was healthy, prudent, fruits and vegetables, fat reduced/diet foods, vegetables/fish/poultry, fruit/wholegrain/dairy, healthy eating index 2005, alternate healthy eating index, Mediterranean score and recommended food score. An elevated risk of CRC was associated with Western diet, pork processed meat, potatoes, traditional meat eating, and refined grain pattern. Conclusion: The Western dietary pattern which mainly consists of red and processed meat and refined grains is associated with an elevated risk of development of CRC. Protective factors against CRC include a healthy or prudent diet, consisting of vegetables, fruits, fish and poultry.

Age Studies on the Butter Fish Population from Southwestern Waters of Korea

  • Han, Pyung Chin
    • 한국해양학회지
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    • v.8 no.2
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    • pp.68-74
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    • 1973
  • The present paper concerns the age determination and growth of butter fish, Pampus argenteus from the southwestern waters of Korea by otolith reading. 743 specimens taken by stow-net in the southern part of the Yellow Sea and northeastern part of the East China Sea during the period from October 1972 to September 1973 were examined. Results of the study are summarized as follows: 1. Sex ratio of females to males was found to be 2:1. 2. Ring marks on the otolith were found to be formed twice a year, once during the period of January-May and the other time in September. 3. The Lee's phenomenon was observed on the otolith sample. 4. The relationship between the radius of otolith(R) and fork length(L) was found to be as follows: R=0.3069+0.0133L 5. Calculated fork length at the time of otolith ring formation are found to be as follows:I-ring,71.67mm; II-ring, 125.05mm; III-ring, 168.65mm; IV-ring, 201.74mm; V-ring, 225.80mm; VI-ring, 240.84mm. 6. Maximum fork length calculated according to the diagram of Walford's growth transformation was found to be 281.5mm. 7. Growth curve, when related to the von Bertalanffy's equation, was laid out as $L_{t}=281.5[1-e$^{-0.674(t-0.128)}]$

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Prevalence and Factors Associated with Opisthorchis viverrini Infection in Khammouane Province, Lao PDR

  • Saiyachak, Khamphanavanh;Tongsotsang, Sutthiporn;Saenrueang, Thitima;Moore, Malcolm A;Promthet, Supannee
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1589-1593
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    • 2016
  • Opisthorchis viverrini (OV) liver flukes are common parasites found in central and southern Laos and constitute a major public health problem in the country. Laos people continue to have the habit of extensively consuming raw or half-cooked fish which are intermediate hosts. This study aimed to determine the prevalence and factors associated with OV infection in the population of Thakek district, Khammouane Province. This cross-sectional analytic study covered 237 subjects who filled out structured questionnaires. Fecal examination for OV infection was performed by Kato's thick smear method. Data analysis was carried out using STATA Version 10.0. Multiple logistic regression was applied. The results showed that the infection rate of OV was 54.8%. Factors associated with OV infections were gender, a habit of defecation in fields and raw fish (goi bplaa dip) consumption. Opisthorchiasis and associated cholangiocarcinoma development thus appear to remain as important concerns in Laos.

Molecular Phylogeny of Pungitius kaibarae from Mitochondrial DNA Sequences in Selected Streams Flowing into the East Sea (동해유입천에 서식하는 잔가시고기의 미토콘드리아 DNA를 이용한 계통분류학적 연구)

  • Jang, Min-Ho;Yoon, Ju-Duk;Chae, Byung-Soo;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.39 no.2 s.116
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    • pp.265-270
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    • 2006
  • The nucleotide sequence variations of mitochondrial DNA were investigated to understand genetic differentiation for five different Pungitius kaibarae populations at five study sites from selected four streams flowing into the East Sea. The complete sequences of mtDNA control regions of them were determined the constant sites 342 bp and variable sites 183 bp including parsimony infromative sites 122 bp. Based on the phylogenetic tree, five populations were monophyletic unit (97% MPand 100% NJ) and separated two groups (Myongpa-Songhuen stream group and others group). The population of Baebong stream (82nd bp, G-A) consistently formed them of the Jasan stream into a monophyletic unit even though it is closer then Myongpa stream (99th bp, T-C) from the Baebong stream. Further studies on the molecular phylogeny for the primary freshwater fish are needed to establish for the fish biodiversity conservation in mountainous and upland streams.

A Study on 'Tang', Traditional Soup Originated in Kyoung-Nam Province (경남지방의 향토요리에 관한 연구 -탕류를 중심으로-)

  • Kim, Kyoung-Ja;Kwak, Yun-Joo;Kim, Mung-Jin;Kang, Sun-Hee
    • Korean journal of food and cookery science
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    • v.6 no.3 s.12
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    • pp.67-83
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    • 1990
  • Currentry, the originality of traditional soups in Kyoung-Nam province is vanishing by the inflex of processed and instant food, food industrial development. Especially, such factors as the influence of alien cooked, the develoment of transportation, the movement of population have made it hard to preserve the traditionnal food preparations. The purpose of this thesis was to seek out the various kinds of Kyoung-Nam province soups preparation. To do this, about 60 kinds of soups recipe were reviewed and charactered into several categories. The findings of the study are as follows. 1) Soup is made by fish or shellfish, freshwater fish. Meat and fowls is rarely used in Kyoung-Nam province (coastal region). 2) Soups of inland area is made by most vegetables and these soup were always harmonized with soybean powder or perilla powder. 3) Various soup season with the mag-jang, mul-jang sauce, hab-ja-jang sauce. 4) These soups were in general to make much red pepper and much salt.

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