• 한국가금학회지
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• 제27권2호
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• pp.109-114
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• 2000

The objective of these experiments was to develop an attenuated thermostable Newcastle disease virus(NDV), CBP-1 strain isolated from infected pheasants. Safety, pathogenicity and protective effects against velogenic NDV were also investigated to evaluate if the attenuated NDV, CBP-1 strain could be a candidate for a new NDV vaccine strain. CBP-1 strain was passaged up to the 173 times by nine days old embryonated eggs and chicken embryo fibroblast(CEF) cell cultures. Its sensitivitly to lipid solvents and low pH, thermostability, mean death time(MDT), intracerebral pathogenicity index(ICPI) of one day old chicks and intravenous pathogenicity index(IVPI) of four weeks old chicks were examined. Safety, boosting and protective effects were tested by chicks mortality. CBP-1 NDV strain had significant thermostability at 56$\^{C}$ for 30 minutes. by hemagglutinin activity and egg infectivity test, but was not resistant to lipid solvent. It showed possibility to use as a feed or water vaccine because of the resistance to low pH. MDT, ICPI and IVPI of CBP-1 were attenuated from 51.5, 1.96, 2.60 to 112.4, 1.12, 1.45. These results implied that the 173rd passages in embryonated egg and CEF cell cultures induced a substantial attenuation of the pathogenicity of the parent virus, changing the virulence from velogenic to intermediate between mesogenic and lentogenic. After vaccination with CBP-1 at one day old by drinking water mortality was 17.5%. However, spray vaccination with B1 at one day old, CBP-1 at two weeks ild and challenge with velogenic Kyojeongwon strain at four weeks old showed 93.5% survival rate. Mortality of chicks, vaccination with 173rd passaged CBP-1 strain at one day old, two weeks old and challenge with Kyokeongwon strain at four weeks old, was 20.0%. The results of these studies indicated that partial attenuated CBP-1 strain tended to be a low safety for ND of broiler chicks and would need to be more successive attenuation.

• 한국동물위생학회지
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• 제28권4호
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• pp.367-373
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• 2005

Coccidiosis of domestic fowl is a parasitic disease that infects poultry drastically and can cost the pastured poultry producer much in the course of a year. Two hundred forty, day-old-broiler chicks were purchased and were randomly divided in eight groups, containing thirty birds in each group. Decoquinate $6\%$, maduramicin ammonium $2\%$, monensin sodium $13.2\%$, salinomycin sodium $12\%$, a live attenuated vaccine, and trivalent live attenuated vaccine, was provided to the day chicks of six groups, respectively. The chicks of last two groups served as infected non-medicated and uninfected non-medicated, respectively. Feed consumption, weight gain, feed conversion ratio, mortality and oocyst count per gram feces were recorded during the conduction of the experiment. Among treated groups, performance of salinomycin group was significantly better (p<0.05) in all aspects. Salinomycin acts against the sporozoites, trophozoites and first generation schizonts and is highly effective against the economically important species of Eimeria. The present study confirms that use of salinomycin, as an anticoccidial, is a drug of choice.

• Environmental Engineering Research
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• 제20권4호
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• pp.356-362
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• 2015

Many burial sites were constructed in a short time to prevent the rapid spread of foot and mouth disease in infected livestock carcasses in Korea. More than 4,700 carcass burial sites were constructed in 2011. Approximately seven million poultry and 3.5 million livestock, including cattle and swine, were buried on farmland. Some burial sites were suspected of leachate leakage and were excavated and carcasses redisposed in a bioaugmentation process. This study performed interviews in order to understand the economic issues related to carcass burial and redisposal. The internal data from local government and the assumption data from online sites were analyzed to evaluate the costs; the focus was on burial site construction. The results showed that the local government paid $4.7 and $10.9 per carcass for traditional burial and redisposal. The comparable costs shown online were $4.5. This study found that the standard operating procedures should be carried out to reduce environmental impact and avoid additional costs. We estimated that the cost could be reduced by the advance preparations of materials against the emergency situations such as catastrophe of epidemics. In addition, the innovative technology for the stabilization of carcasses should be established through a future study.

• 한국동물위생학회지
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• 제39권1호
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• pp.21-28
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• 2016

Protozoan parasite, the genus Eimeria, causes an intestinal disease, coccidiosis, in young broilers. Coccidiosis induces significant economic loss in poultry production. This study was designed to identify the prevalence of Eimeria spp. in broilers in Gyeonggi province, Korea. Fecal samples from broilers at 94 farms were collected in two chicken slaughterhouses between March and June 2015. Eimeria infection was determined by microscopic examination and PCR using ITS-1 region. The prevalence of Eimeria was 58.5% (55 of 94). E. acervulina was identified in 96.4% of samples, E. tenella in 81.8%, E. maxima in 12.7%, E. praecox in 12.7%, E. brunetti in 5.5%, E. necatrix in 1.8%, and E. mitis in 1.8%. Body weight (BW) of broilers infected with both E. tenella and E. acervulina ($mean=1.53{\pm}0.19^Bkg$) was significantly lower than broilers with E. acervulina positive/E. tenalla negative ($mean=1.74{\pm}0.07^Akg$) or Eimeria negative ($mean=1.65{\pm}0.15^Akg$) (Duncan's multiple range test, P<0.01). High prevalence of Eimeria tenella and the impact on the broiler body weight shows the importance of this protozoa in broiler industry. Development of the periodic monitoring strategy and systemic management for the purpose of the prevention/eradication of Eimeria infection among broilers is required.

• 한국동물위생학회지
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• 제38권1호
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• pp.51-56
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• 2015

Infectious bronchitis virus (IBV) causes an acute and highly contagious viral disease of chicken that is great economic losses to the poultry industry worldwide. Among the IBV structural proteins, the high rate spike glycoprotein S1 gene mutation and antigenic variant strains have been reported in many countries. During the years 2012~2014, 10 IBV strains were isolated from infected chicken farms distributed in provinces of Jeonbuk. Analysis of the S1 gene sequences amplified from 10 isolated strains with QX strains showed nucleotide homologies ranging from 96.5 to 95.4%. Phylogenetic analysis revealed that all strains were clustered into QX-like groups. This study suggests that QX-like IBVs are circulating in commercial chicken farms in Jeonbuk. Therefore, the continuing survellance is significantly important for prevention and control of BIV infection.

• Journal of Veterinary Science
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• 제22권2호
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• pp.21.1-21.6
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• 2021

In this study, we describe the isolation and characterization of previously unreported Y280-lineage H9N2 viruses from two live bird markets in Korea in June 2020. Genetic analysis revealed that they were distinct from previous H9N2 viruses circulating in Korea and had highest homology to A/chicken/Shandong/1844/2019(H9N2) viruses. Their genetic constellation showed they belonged to genotype S, which is the predominant genotype in China since 2010, where genotype S viruses have infected humans and acted as internal gene donors to H5 and H7 zoonotic influenza viruses. Active surveillance and control measures need to be enhanced to protect the poultry industry and public health.

• 한국가금학회지
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• 제37권3호
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• pp.283-287
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• 2010

본 연구에서는 SE에 특이적인 박테리오파아지($CJ{\phi}07$)의 사료 및 음수 투여가 어린 병아리의 SE 감염에 따른 장내 균증식과 체외 균배출에 미치는 영향을 평가하고자 실시하였다. 박테리오파아지를 투여한 SPF 병아리에 SE균을 공격 접종 한 뒤, 공격 접종 10일 후 채취한 맹장 분변에 존재하는 SE균 수를 측정한 결과, 박테리오파아지를 투여한 병아리의 맹장 분변 내 SE균 수는 양성 대조군에 비하여 유의성 있게 감소하였다(P<0.05). 또한, 공격 접종 10일 후 사육 시설 표면의 SE균 오염도를 측정한 결과, 박테리오파아지를 투여한 그룹의 사육 시설에서 채취한 환경 시료의 SE균 오염율(50%)이 박테리오파아지를 투여하지 않은 그룹의 SE균 환경 오염율(100%)에 비하여 감소되는 것을 통해 박테리오파아지 $CJ{\phi}07$에 의한 장내 균 증식과 체외 균 배출 억제 효능이 확인되었다. 따라서 박테리오파아지 $CJ{\phi}07$는 항생제 대체 물질로서 가금에서의 SE 감염을 효과적으로 방어할 수 있을 것으로 판단된다.

• 한국동물위생학회지
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• 제28권1호
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• pp.1-21
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• 2005

Pullorum disease and Fowl typhoid are kind of poultry specific disease for poultry. The peculiar character of these poultry specific diseases is that it can be infected by transmitting vertically and horizontally, also it is hard to be discovered by clinical sign, and pathology or immunology. So, to develop the PCR method which distinguishes these two genetically similar diseases of separated the specific DNA fragment from each strain and use it for differential diagnosis by subtraction PCR method. Standard strain of S gallinarum and S pullorum, and field isolation strain were verified by biochemistry, It confirmed existence of plasmid by using the PFGE. Then, Isolated DNA from it and used it as materials for the experiment. After cutting genomic DNA of two strains by using Sau 3Al, It ligated primer to tester DNA for PCR amplification and separated specific DNA fragment bacteria with method of subtraction PCR. And, It confirmed that it is a piece of unique DNA in every bacteria using base sequence of separated DNA fragment. 1. The six specific DNA fragment were separated from the DNA of S gallinarum and S pullorum by the subtraction PCR method. 2. In the result of comparison after setting base sequence of each fragment, each separated base sequence of DNA fragment they did not correspond to each other 3. As the result of each DNA fragment is derived from the each strain of DNA, and there was no homology of genomic DNA level in mutual. 4. The fragment originated in plasmid and includes S pullorum did not separate. 5. In the result of searching base sequence in Genebank, it partially shows homology in Salmonella enterica, S typhimurium, S dublin, Escherichia coli, Shigella flexneri, Yersinia pestis, Klebsiella pneumoniae. 6. Primer design by S gallinarum DNA 2, 3 fragment used PCR, They are positive reaction in only S gallinarum at 276, 367 bp position.

• 한국가금학회지
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• 제32권2호
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• pp.113-123
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• 2005

본 연구는 약병원성 조류인플루엔자 사독백신 개발을 위하여 백신 후보주(ADL0401)로서의 생물학적 특성 및 개발 백신에 대한 면역원성 및 안전성 평가를 실시하였다. 백신 후보주인 ADL0401의 병원성을 조사한 결과 폐사는 없었으며, 임상증상 및 바이러스 재분리율 양상이 국내 표준 야외주인 MS96과 상당히 유사한 생물학적 특성을 나타내어 약병원성 조류인플루엔자의 특징을 갖고 있음을 알 수 있었다. 표준야외주인 MS96과 백신후보주인 ADL0401간의 이종항원의 중화능 실험을 한 결과 r값 = 0.71로 동종항원(r값 = 1)에 비하여 다소 낮은 중화능을 나타내었지만, 두 바이러스간의 항원성엔 큰 차이가 없음을 알 수 있었다. 불활화 능력실험으로 $0.1\%$ Formalin을 $37^{\circ}C$ 조건에서 처리하였을 때 가장 효과적인 결과를 가져왔으며, MS96은 2시간, ADL0401은 1시간만에 다소의 역가 저하는 있었으나 빠르게 불활화가 이루어짐을 확인하였다. 개발 백신의 면역원성 및 안전성 실험 결과 ISA 70 adjuvant 백신 접종시 백신 접종 전후로 폐사율 및 임상증상은 관찰되지 않았으며, 높은 수준의 항체 역가를 형성함으로써 가장 면역원성이 우수한 것으로 확인되었다.

• 한국가금학회지
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• 제46권4호
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• pp.313-325
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• 2019

일반적으로 고병원성 조류인플루엔자(HPAI; highly pathogenic avian influenza)가 발생을 하면 일정한 방역지역을 선정하여 그 범위 내의 농장에 대해서는 일괄적 살처분을 진행한다. 그러나 이러한 살처분은 산업에 막대한 경제적 손실을 줄 수 있지만, 방역 범위를 줄이게 되면 수평전파의 위험성이 커지게 된다. 따라서 본 연구에서는 국내 가금농장의 차단 방역 수준과 HPAI 발생 위험도를 측정할 수 있는 방법을 마련하고, HPAI가 발생 시 방역지역에 포함된 농장들을 선별적으로 살처분을 할 수 있는 방안을 마련하고자 수행하였다. 국내 가금농장의 계종, 규모, 지역에 따라 전국적으로 8개의 농장을 선정하였으며, 일반관리 51항목, 방역관리 106항목, 위생관리 26항목으로 총 183 항목으로 나누어 차단 방역 수준을 평가하였다. 전반적으로 산란계 농장인 5개 농장(JS, GE, CS, HS, OE)이 복지농장 (CH), 육계농장(JG, LB)보다 종합적으로 높은 수준의 점수를 획득하였다. 산란계 농장은 대부분 130점에서 157점 사이에 있는 반면, 육계농장은 45점과 75점이었으며, 복지농장은 70점 수준으로 농장간 차단 방역 수준 편차가 심하였다. 평상시 가금농장의 HPAI 발생의 위험도도 일반관리, 방역 관리, 위생관리로 나누어 평가한 후 기존의 각 농장별 현재의 차단 방역수준과 서로 비교하였다. 현재의 차단 방역 수준이 HPAI 발생 위험도보다 높은 수준의 농장의 경우 대부분이 3개 관리 분야 중 방역 관리가 뛰어나다는 공통점이 있었으며, HPAI 발생 위험도가 현재의 차단 방역 수준을 능가하는 경우에는 대부분 3개 분야의 관리가 전반적으로 취약하였지만, 특히 방역 관리수준이 매우 낮은 점수를 취득하였다. 이와 같이 본 연구에서 제시한 가금농장의 차단 방역 수준 평가를 위한 항목들을 활용을 하면 현재 가금농장의 차단 방역 수준을 평가할 수 있을 뿐 아니라, HPAI 발생에 대한 위험도를 추정할 수 있다. 따라서, 이러한 위험도 평가를 HPAI 발생시 방역 지역 내 농장에 다른 요소들과 함께 적용을 한다면 선택적 살처분의 가능성도 높아질 것으로 판단된다.