• Title/Summary/Keyword: 도태

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Resistance Development and Cross-Resistance of Chlorpyrifod, dichorovs and Permethrin-Selected House Fly (Musca domestica L.) (집파리에 대한 Chlorpyrifos, Dichlovos 및 Permethrin의 저항성 유발과 교차저항성)

  • 이용규;김정화;이형래
    • Korean journal of applied entomology
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    • v.33 no.3
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    • pp.166-172
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    • 1994

  • This study was conducted to investigate the resistance development and cross-res~stance of house fly (Musco dornestica L.) selected with chlorpyrifos, dichlorvos and permethrin for 11 generations to various p u p s of insectiodes. The resistance ratio (RR) of the chlorpyrifos-selected (Q), the d~chlorvos- selected (&) a d the permethrin-selected (R,) stmlns were 42 0. 38 and 187 tlrnes in female. and 42.0, 4 1 and 16.4 time; in male from the susceptible strain, respectively. The Rc strain showed highest cross-resistance to permethlin among the insectic~des tested: RR=7.5 and 9.6 tunes in female and male, respectively, whereas negatively correlated cross-resistance to propoxur was observed. High cross-res~atance to chlorpyrifos were produced for female (RR= 13.3) and male (RR=15.9) of Rd strain, and female (RR=8.7) and male (RR= 9 7) of R, strain. respectively

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Joint Toxic Action of Insecticide Mixtures to the Cupermethrin-and Pirimicarb-Selected Strains of Green Peach Aphid(Myzus pericae Sulzer) (Cypermethrin과 Pirimicarb 저항성계통 복숭아혹잔딧물에 대한 살충제문의 연합독작용)

  • 안용준;김길하;최승윤
    • Korean journal of applied entomology
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    • v.28 no.1
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    • pp.32-36
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    • 1989

  • The joint toxic action of mixtures of cypermethrin or pirimicarb with one of other insecticides (acephate, cypermethrin, demeton-S-methyl and pirimicarb) on the cypermethrin or picimicarb-selected green peach aphid (Myzus persicae Sulzer)was investigated. The responses depended on the choice and ratios of insecticide combination. In the cypermethrin-selected strain bioas-say, mixtures of test insecticides showed no synergistic effect. On the other hand, the maxi-mum synergistic effects for the pirimicarb-selected strain were obtained at the 8 : 2 ratio of pirimicarb and demeton-S-methyl exhibited antagonistic effect.

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Effects of Twin Birth on the Occurrence of Postpartum Disorders, Culling and Reproductive Performance, and its Risk Factors in Dairy Cows (젖소에서 쌍태분만이 산후질병 발생, 도태 및 번식능력에 미치는 영향과 쌍태 위험 요인)

  • Kim, Ill-Hwa;Kang, Hyun-Gu
    • Journal of Veterinary Clinics
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    • v.28 no.4
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    • pp.339-343
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    • 2011

  • This study determined the effects of twin birth on subsequent postpartum disorders, culling and reproductive performance, and its risk factors in dairy cows. Detailed data related to reproduction, health, and calving events, including dates of artificial insemination (AI) and calving, hormonal treatment prior to conception, cow parity, twin birth, retained placenta, metabolic disorders, and endometritis were collected from 1,717 individual calvings on 9 dairy farms. The incidence rate of twin birth was 3.4%. Gestation length was shorter in cows with twin birth ($270.6{\pm}2.0$ days) than cows giving birth to singletons ($279.5{\pm}0.2$ days, P < 0.01). The incidence of retained placenta (47.5 vs. 16.0%), metabolic disorders (18.6 vs. 3.8%) endometritis (62.7 vs. 28.2%), and culling rate (32.2 vs. 16.5%) was greater in cows with twin birth than in cows giving birth to singletons, respectively (P < 0.01). The hazard of pregnancy (adjusted hazard ratio, AHR) by 210 days in milk analyzed using Cox proportional hazards model was affected by calving season, in that the rate of pregnancy for cows calved during spring was less than for cows calved during winter (AHR = 0.80; P = 0.01); this was also true for endometritis (AHR = 0.46, P < 0.01). AHR was not affected by twin birth. Logistic analysis demonstrated that increasing the cow parity (P < 0.01) and hormonal treatment prior to conception (adjusted odds ratio, AOR = 1.84, P < 0.05) increased the risk of twin birth. These results demonstrate that twin births are responsible for severe economic losses through the increased occurrence of postpartum disorders and culling; thus, appropriate management for the deleterious impact of twin birth, and/or reducing the risk factors by herd control regarding cow parity and the use of reproductive hormones prior to conception might be necessary.

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전염성 훼브리셔스낭병

  • 김순재
    • KOREAN POULTRY JOURNAL
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    • v.15 s.160
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    • pp.91-95
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    • 1983

  • 직접 및 간접적인 고도의 전염병으로 닭에서만 발생하는 본 병은 한번 발생한 계사내에는 감염계를 도태한 후에도 상당기간 감수성계에 전염되어 발병시킬 수 있는 급성 전염병이다.

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