• 대한수의학회지
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• 제47권4호
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• pp.417-423
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• 2007

Serological surveillance programs in animal populations are becoming increasingly important to estimate prevalence of a specific disease and subsequently to document disease-free status in a region or a country. For these purposes, the programs need to be based on both theoretical and economical aspects from the designing phase. From Aujeszky's disease (AD)-eradication program point of view, group of animals (aggregates, herds) not individual animal is the more important sampling unit of concern. In this study the authors therefore attempted to compute an appropriate sample size tailored to a current surveillance program against AD, assuming that the goal of this program is either herd-level prevalence estimation or documentation of AD-freedom. For prevalence estimation, assuming a finite population with imperfect sensitivity (Se) and specificity (Sp) of ELISA kit for AD diagnosis, the number of herds present, expected herd prevalence, and desired accuracy for a certain level of confidence, sample size was estimated at herd-level in the first stage and individual animal-level in the second stage. A two-stage sampling design was used to calculate a sample size to indicate AD-freedom. In this instance, the computation was based on the possible detection of a predetermined prevalence at a certain herd-level Se and Sp. This study indicated that the sample size varied with predetermined confidence, tolerance, Se and Sp at herd- and animal-level, and within- and among-herd prevalence. In general, smaller sample size was required to estimate AD prevalence than to document of AD-freedom. Compared to individual-based samples, two-stage sampling strategy requires a larger sample size to show disease-freedom. Statistical considerations including herd-level test characteristics when designing surveillance program also are further discussed.

• 한국동물위생학회지
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• 제24권1호
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• pp.9-14
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• 2001

This study was carried out to investigate the prevalence of Neospora caninum infection in dairy cow and Korean native cattle(KNC), raised in several Chungnam province. To determine the prevalence of antibodies to N caninum, a total of five hundred fifty six sera were analyzed by indirected fluorescent antibody(IFA) test. Five hundred thirty three sera were collected from fifteen dairy herds and twenty three sera were taken from fourteen KNC herds from December 1999 to November 2000. Seropositive ratio of the dairy cattle sera were individually or herdly tested and showed 64.2% and 93.3%, respectively. It was recorded with 78.6% and 47.8% in KNC. The seropositive ratio of dairy cattle was depended on the size of ranch. It was 92.2, 60.7 and 57.9% at the size of less than thirty, thirty to seventy and more than seventy one cattle, respectively However, it was different from the province of Chungnam. The seropositive ratio to N caninum of dairy cattle were 79.5, 53.1, 61.4 and 31.1% at Gongju, Yeongi, Geumsan and Cheongwon, respectively. It showed difference at the growth stage and sex of cattle. The seropositive ratios of N caninum of calf, heifer, premiparous, multiparous(2nd-5th), multiparous (6>th) and bulls confirmed to 25.0, 50.3, 70.3, 71.2, 50.0 and 50.0%, respectively. It was related with brucellosis in cattle. The infected ones with brucellosis were 75.7% of seropositive ratios to N caninum. The results of this study indicated that N caninum infection was widespread in Chungnam province and confirmed existing with brucellosis in cattle.

• 대한수의학회지
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• 제40권4호
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• pp.707-717
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• 2000

Atropic rhinitis (AR) is one of major respiratory diseases in pigs. AR causes a great economic losses and is considered to be a multifactorial disease in which herd management, heredity, and environment. Several vaccines against have been developed commercially and used in pig farms but the efficacy of each vaccine is still questionable. In this study, one of commercial AR vaccines, which contains inactivated Bordetella bronchiseptica, Pasteurella multocida type D and their toxoid was evaluated for vaccine efficacy by challenge test. Twenty piglets were divided into four groups as follows; group I was piglets from vaccinated sows (twice before parturition); group II was piglets from vaccinated sows (same as group I) and were vaccinated at 1 day old; group III and IV were piglets without any vaccination. Groups I, II, and III were challenged by intranasal instillation of $5.3{\times}10^7$ CFU of B bronchiseptica twice and $1{\times}10^9$ CFU of P multocida five times. Group IV was control group without any vaccination and any challenge. We compared serological results, recovery rate of P multocida by polymerase chain reaction, clinical signs and pathological findings between vaccinated groups and unvaccinated groups for efficacy of the vaccine, Serological responses against B bronchiseptica and toxigenic P multocida type D were not showed evident discrepancy between vaccinated groups and unvaccinated groups assuming that the antibody responses against the vaccine is very delayed. However, growth rate, clinical signs and snout lesion grading in vaccinated groups showed more favorable than those in unvaccinated group. Therefore, AR vaccination in this study is considered to be effective in the prevention of AR in pigs.

• 대한수의학회지
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• 제35권1호
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• pp.143-148
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• 1995

Brucella abortus cell wall antigen was extracted from Brucella abortus 1119-3 by ultrasonication and followed by sodium dodecyl sulfate(SDS) treatment. In order to confirm whether this preparation is serologically cross reactive with Yersinia enterocolitica 0:9, Western blot analysis with mouse anit-Brucella abortus1119-3 and with mouse anti-Yersinia enterocolitica 0:9 was performed. ELISA results from using those Brucella antigen and Yersinia antigen were assessed whether they had correlation. According to the results of western blot analysis and ELISA, there was no evidence of cross reactivity between the Brucella abortus 1119-3 antigen preparation and Yersinia enterocolitica 0:9. Therefore the SDS treated antigen prepared in this study could be suitably used as specific ELISA antigen without confusion in the interpretation of serological tests for brucellosis in cattle.

• 대한미생물학회지
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• 제19권1호
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• pp.65-71
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• 1984

The author attempted serological typing with the slide agglutination and the production of heat-labile enterotoxin (LT) and heat-stable enterotoxin (ST) by the enterotoxingenic eschenchia coli 446 strains isolated from diarrheal patients. The enterotoxingenic E.coli, producing LT and/or St, were detected by use of assays in the reversed passive hemagglutination(RPHA) and the suckling mouse method. The results obstained were as follows: 1. Of 446 strains isolated, 88 strains(19.73%) produced LT, while 224 strains(50.22%) produced ST, 134(30.05%) produced both LT-ST simultaneously. Serological typing were typed into 06, 08, 020, 025, 027, 0126, 0148 and 0159. Serotype 06 had the highest incidence of 26.46% followed by 0148(18.16%), 027(14.57%); 025(10.99%), 0159(4.03%), 0126(3.59%), 020(1.12%) and 08(0.45%). 2. Serotype 06, 08 and 025 almost always produced both LT and ST, whereas serotypes 020, 027 and 0148 almost always produced only ST. And serotypes 06, 025, 0126 and 0159 almost always produced LT or ST. 3. Of 134 LT-ST positive strains, 115 strains were serotype 06, 3 strains were 025, 2 strains were 08, and 14 strains were 0 untypable. 4. Of 224 ST positive strains, 65 strains were serotype 027, 81 strains were 0148, 16 strains were 0159, and 42 strains were 0 untypable. 5. Of 88 LT positive strains, 45 strains were serotype 025, 5 strains were 0126, 2 strains were 0159, and 42 strains were 0 untypable.

• 한국어병학회지
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• 제22권1호
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• pp.23-33
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• 2009

V. harveyi는 양식산업에서 중요한 해산 양식 어류와 새우류에 많은 폐사를 일으키는 병원체로 알려져 있다. 본 연구에서는 해산 양식어류에서 분리된 11개 strain의 Vibrio harveyi의 생화학적, 생리학적, 혈청학적, 면역학적 특성을 조사 하였다. 생화학적 특성과 TCBS agar에서 집락의 색깔이 달라 표현형의 차이가 있었고 V. harveyi 분리균주들은 편모항원에 의해 4개 이상의 혈청형으로 구분되었다. 어류에서 분리된 V. harveyi는 western blotting으로 26-34 kDa 사이에 동일한 크기의 major protein을 갖는 group A로 구분 되었고 넙치에 대하여 표준균주인 V. harveyi KCCM40866 보다 강한 병원성을 갖고 있었다. V. harveyi C05011로 면역 유도된 넙치는 다른 group A 균주를 인위감염 시켰을 때 높은 항병력을 나타내었다.

• 한국동물위생학회지
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• 제33권1호
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• pp.45-50
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• 2010

Mycoplasma gallisepticum (MG) is major cause of chronic respiratory disease in chickens. M. synoviae (MS) most frequently occurs a subclinical upper respiratory infection but may result in airsacculitis and synovitis in chickens and turkeys. Both mycoplasmas induce economic losses by triggering chronic respiratory signs, airsacculitis and decreased egg production. For prevention of the infections, live attenuated andinactivated vaccines are commercially used for prevention of MG but not MS in Korea. Serum plate agglutination (SPA) and enzyme-linked immunosorbent assay (ELISA) have been commonly used for serological diagnosis for MG and MS. Recently, it is believed that MS spread in chickens is very seriously in Korea and respiratory infection with MS causes substantial loss in poultry farms. In this study, we investigated the serological prevalence of MG and MS in unvaccinated chickens between 2008 and 2009. The overall seroprevalence of MG was 24% of 2,094 for individual chickens and 24% of 189 farms. The overall seroprevalence of MS was 36% in 2,095 chickens and 39% in 198 farms. The results show that seropositive ratio of MS is higher than MG. The geographical prevalence of MG has been estimated in following sequence; Gangwon, Jeolla, Gyeonggi, Gyeongsang, and Chungcheong. The geographical prevalence of MS has been estimated as follows; Gangwon, Gyeonggi, Gyeongsang, Chungcheong, and Jeolla. Seasonal seroprevalencewas also examined, and it found that seroprevalence in spring, fall and winter was higher than that in summer in MG, but not in MS. No significant difference was shown in seroprevalence according to breed. Future study about pathogenicity of MS isolates would be needed and economical losses by MS outbreaks should be analyzed. Moreover, we compared sero-positivity obtained with SPA and ELISA. The kappa value of MG between SPA and ELISA was 0.8061 and the kappa value of MS between SPA and ELISA was 0.7649.

• 대한수의학회지
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• 제45권3호
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• pp.311-323
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• 2005

This study tested the effect of a trivalent (feline panleukopenia; FPV, feline viral rhinotracheitis; FHV, feline calicivirus infection; FCV) inactivated vaccine in cats. The vaccine was tested for the safety in guinea pigs, mice and cats. Also, it was tested for the efficacy in cats. The vaccine was inoculated to cats at 7~9 and 10~12 weeks of age (conventional schedule) and the serological response to vaccination was assessed and was compared to the unvaccinated group. All cats were bled by jugular venipuncture for FPV, FHV and FCV specific serological test (virus neutralizing antibody, VN) at 7~9, 10~12 and 13~15 weeks. After last bleeding, all cats were inoculated with each virus (FPV : orally $2ml\;10^{7.5}\;TCID_{50}/ml$, FHV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$ and FCV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$). The Vaccine verified excellent protective effect in guinea pigs, mice and cats. The VN antibody titers of the unvaccinated group cats against FPV, FHV and FCV were <2~16, on the other hand the vaccinated group cats were $512{\sim}{\geq}4096$, 64~1024 and 64~1024, respectively. When all cats were challenged with virulent viruses, the survival rates of the vaccinated group cats were over 80%, while the survival rates of the unvaccinated group cats were less 20%. The typical clinical signs were not observed in the vaccinated group cats, but the typical clinical signs and histopathological lesions were observed in the unvaccinated group cats. As the result of tests, the VN values obtained in this study appeared to be high enough to protect cats from viral challenges. The trivalent (FPV, FHV, and FCV) inactivated vaccine seemed to be very effective, for prevention of feline viral diseases (FPV, FHV, and FCV).

• 한국동물위생학회지
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• 제34권4호
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• pp.297-301
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• 2011

Rabies virus is transmitted most commonly through a bite from an infected dog. Especially, stray dogs that are not excluded from contact with rabid wild animals can become rabies vectors. Therefore, serological survey of rabies virus from stray dogs in Seoul Metropolitan City was carried out in this study. To investigate prevalence of rabies antibodies in the stray dogs, serum samples were taken from 500 stray dogs between April and December 2010. Antibodies to rabies virus were detected by indirect ELISA. Of 500 tested sera, 147 (29.4%) were positive to rabies virus. Prevalence rates of rabies antibodies(PRRA) in northern and southern Han river region of Seoul were 26.4% and 33.2% respectively. PRRA in male and female dogs were 33.6% and 26.1% respectively. PRRA in less than 1 year, 1~2< years, 2~3< years, 3~5< years, 5~10< years and over 10 years old dogs were 12.7%, 21.6%, 26.4%, 36.4%, 32.5% and 46.4%, respectively. These results indicates that antibody seroprevalence to rabies is still not enough to prevent rabies and rabies vaccination is required to enhance the seroprevalence in the dogs. To improve the situation, measures to raise public awareness of rabies and its prevention is needed. Also, reducing stray dogs and keeping companion animals from contact with wild animals are indispensable for the prevention of rabies.

• 한국임상수의학회지
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• 제25권6호
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• pp.435-439
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• 2008

We evaluated the patterns of serology and fecal viral shedding for any differences by hemagglutination inhibition (HI) and real-time PCR on Korean CPV-2 isolates (CPV-2a-I, CPV-2a-V and CPV-2b). We successfully detected fecal viral shedding from samples extracted 2-3 d.p.i., regardless of the onset of clinical signs. In addition, the pattern of viral shedding differed depending on the CPV-2 isolates used for inoculation. We also observed differences in the serological pattern that was also depended on the CPV-2 isolates inoculated. The onset and amount of fecal viral shedding were not correlated with the level of antibody titers in this study. Our study is a valuable resource for understanding the different pathobiology of the CPV-2 isolates and the correlation between the patterns of serum antibody titer and fecal viral shedding.