An indirect porcine epidemic diarrhea (PED) virus (PEDV) enzyme-linked immunosorbent assay (ELISA) was compared with the serum neutralization (SN) test by testing 46 samples from experimentally infected sows, 73 samples from naive sows, and 1, 024 field sow samples from 48 commercial swine farms of undefined PED status. The SN test and the ELISA were performed using PEDV, KPEDV-9 strain. Viral proteins as a coating antigen of PEDV ELISA were extracted from the cytoplasm of PEDV-infected Vero cells using a non-ionic detergent, Triton X-100, and a simple protocol of PEDV ELISA was followed. The presence of antibodies in these experimental samples was confirmed by SN and ELISA in which the sensitivity of the ELISA was 89.1%, and the corresponding specificity was 94.5%. On testing 1, 024 field samples, an overall agreement of 84.2% was generated between the SN and ELISA. This study demonstrates that the PEDV ELISA is a useful serodiagnostic screening test at herd level for detecting swine antibodies against PEDV.
Animals ; Antibodies, Viral/blood ; Coronavirus Infections/diagnosis/*veterinary/virology ; Diarrhea/diagnosis/*veterinary ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Neutralization Tests/veterinary ; Sensitivity and Specificity ; Swine ; Swine Diseases/diagnosis/*virology

Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n=101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials.
Allergens/*blood ; Animals ; Dermatitis, Atopic/etiology/*veterinary ; Dog Diseases/*etiology ; Dogs ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Immunization/*veterinary ; Immunoglobulin E/*blood ; Male

An ELISA was established to measure bovine IgG directed against the recombinant antigenic determinant of Nc-p43, a major surface antigen of Neospora caninum. In a previous study, two thirds of the Cterminal of the molecule was expressed as a 6 x His tagged protein (Ncp43P) for ELISA using 2/3 of the N-terminal of SAG1 from Toxoplasma gondii as a control (TgSAG1A). Among 852 cattle sera collected from stock farms scattered nation-wide, 103 sera (12.1%) were found to react with Ncp43P positively, but no positive reaction was observed with TgSAG1A. This study shows that Ncp43P could be available as an efficient antigen for the diagnosis of neosporosis in cattle. Furthermore, it together with TgSAG1A, could be useful for the differential diagnosis of N. caninum and T. gondii infections in other mammals.
Animals ; Antibodies, Protozoan ; Cattle ; Cattle Diseases/diagnosis/epidemiology ; Coccidiosis/diagnosis/epidemiology/veterinary ; Enzyme-Linked Immunosorbent Assay/methods/*veterinary ; Immunoglobulin G/*analysis ; Neospora/*immunology ; Protozoan Proteins/*immunology ; Seroepidemiologic Studies

Several epidemiological surveys have reported the prevalence of Toxoplasma gondii infection in stray cats in Korea, but little information is available on T. gondii infection in household cats. The aim of the present study was to assess the prevalence and risk factors of T. gondii infection among household cats reared in Seoul, Korea. A total of 474 blood samples were collected from clinically healthy household cats. All samples were tested using ELISA and PCR. The risk factor analysis was based on a questionnaire filled out by the owners. The overall positive rate for ELISA and PCR assays was 2.2% (10/437) and 2.1% (10/474), respectively. With regard to the origin of cats, the positive rates among cats adopted from the animal shelter and veterinary clinic for stray cats were significantly different (P<0.05). Our study demonstrated that the positive rate of T. gondii infection in household cats was low and that this low prevalence was assumed to be associated with keeping the cats indoors and restriction of eating raw food and uncooked meat. Therefore, we suggest that the owners check the origin of the cats prior to adoption to prevent infection of other animals, including humans.
Animals ; Cat Diseases/epidemiology/*parasitology ; Cats ; Enzyme-Linked Immunosorbent Assay/veterinary ; Polymerase Chain Reaction/veterinary ; Prevalence ; Republic of Korea/epidemiology ; Risk Factors ; Toxoplasma/*isolation & purification ; Toxoplasmosis, Animal/epidemiology/*parasitology

Monoclonal antibody against kanamycin was prepared, and competitive direct ELISA and immunochromatographic assay were developed using the antibody to detect kanamycin in animal plasma and milk. The monoclonal antibody produced was identified to be IgG1, which has a kappa light chain. No cross-reactivity of the antibody was detected with other aminoglycosides, indicating that the monoclonal antibody was highly specific for kanamycin. Based on competitive direct ELISA, the detection limits of kanamycin were determined to be 1.1 ng/ml in PBS, 1.4 ng/ml in plasma, and 1.0 ng/ml in milk. The concentration of intramuscularly injected kanamycin was successfully monitored in rabbit plasma with competitive direct ELISA. Based on the colloidal gold-based immunochromatographic assay, the detection limits of kanamycin were estimated to be about 6-8 ng/ml in PBS, plasma, and milk. The immunochromatographic assay would be suitable for rapid and simple screening of kanamycin residues in veterinary medicine. Screened positives can be confirmed using a more sensitive laboratory method such as competitive direct ELISA. Therefore, the assays developed in this study could be used to complement each other as well as other laboratory findings. Moreover, instead of slaughtering the animals to obtain test samples, these methods could be applied to determine kanamycin concentration in the plasma of live animals.
Animals ; Anti-Bacterial Agents/*analysis ; Antibodies, Monoclonal ; Chromatography/methods/veterinary ; Enzyme-Linked Immunosorbent Assay/methods/*veterinary ; Kanamycin/*analysis ; Mice ; Milk/*chemistry ; Rabbits

A 3-yr-old female mongrel dog was referred to the Veterinary Teaching Hospital of Chungnam National University in the Republic of Korea. An adult heartworm, Dirofilaria immitis, was found in the abdominal cavity of the dog during spaying. Dirofilariasis in this dog was also diagnosed by modified Knott's test, ELISA test, and PCR analysis. The present case is the first report on the migration of an adult dog heartworm to the abdominal cavity of a dog in the Republic of Korea.
Abdomen/*parasitology/pathology ; Animals ; Dirofilaria immitis/*physiology ; Dirofilariasis/*parasitology/pathology ; Dog Diseases/*parasitology/pathology ; Dogs ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Polymerase Chain Reaction/veterinary

Lyme disease is a tick-borne zoonotic infectious disease caused by Borrelia burgdorferi. The present study assessed the infection status of B. burgdorferi among horses reared in Korea using ELISA and PCR. Between 2009 and 2013, blood samples were collected from 727 horses throughout Korea. Data for each animal including age, gender, breed, and region of sample collection were used for epidemiological analysis. Overall, 38 (5.2%; true prevalence: 5.5%) of 727 horses were seropositive by ELISA. There were statistically significant differences according to breed and region (P<0.001) whose differences might be attributed to the ecology of vector ticks and climate conditions. Using 2 nested PCR, none of the samples tested positive for B. burgdorferi. Thus, a positive ELISA result can indicate only that the tested horse was previously exposed to B. burgdorferi, with no certainty over the time of exposure. Since global warming is likely to increase the abundance of ticks in Korea, continuous monitoring of tick-borne diseases in Korean horses is needed.
Animals ; Antibodies, Bacterial/blood ; Borrelia burgdorferi/*physiology ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Horse Diseases/*epidemiology ; Horses ; Lyme Disease/epidemiology/*veterinary ; Male ; Republic of Korea/epidemiology

OBJECTIVEIn this study, we evaluated the diagnostic efficiency of six recombinant proteins for the serodiagnosis of Lyme borreliosis (LB) and screened out the appropriate antigens to support the production of a Chinese clinical ELISA (enzyme-linked immunosorbent assay) kit for LB.

METHODSSix recombinant antigens, Fla B.g, OspC B.a, OspC B.g, P39 B.g, P83 B.g, and VlsE B.a, were used for ELISA to detect serum antibodies in LB, syphilis, and healthy controls. The ELISA results were used to generate receiver operating characteristic (ROC) curves, and the sensitivity and specificity of each protein was evaluated. All recombinant proteins were evaluated and screened by using logistic regression models.

RESULTSTwo IgG (VlsE and OspC B.g) and two IgM (OspC B.g and OspC B.a) antigens were left by the logistic regression model screened. VlsE had the highest specificity for syphilis samples in the IgG test (87.7%, P<0.05). OspC B.g had the highest diagnostic value in the IgM test (AUC=0.871). Interactive effects between OspC B.a and Fla B.g could reduce the specificity of the ELISA.

CONCLUSIONThree recombinant antigens, OspC B.g, OspC B.a, and VlsE B.a, were useful for ELISAs of LB. Additionally, the interaction between OspC B.a and Fla B.g should be examined in future research.

Antigens, Bacterial ; blood ; Bacterial Proteins ; analysis ; China ; Enzyme-Linked Immunosorbent Assay ; veterinary ; Lyme Disease ; diagnosis ; Recombinant Proteins ; analysis ; Sensitivity and Specificity ; Serologic Tests ; veterinary

The Japanese encephalitis virus (JEV) is one of causative agents of reproductive failure in pregnant sows. An indirect enzyme-linked immunosorbent assay (I-ELISA) was examined for its potential use in the rapid monitoring of the JEV, and the results were compared with those from the hemagglutination inhibition (HI) and serum neutralization (SN) tests. The comparative analysis showed that the results of I-ELISA showed a significant correlation with the conventional HI (r = 0.867) and SN tests (r = 0.804), respectively. When the I-ELISA results were compared with the traditional diagnostic assays, the sensitivity of the I-ELISA was 94.3% with the HI test and 93.7% with the SN test, respectively. The specificity was found to be 81.4% and 80.0% with the HI and SN tests, respectively. To determine the applicability of I-ELISA in the field, the serum samples from 720 pigs were collected from 4 regions in Korea between July and August 2004. The results indicated that 21.7% of screened pigs were seropositive for the JEV. The seropositive rates of JEV in the 4 provinces were 12.6% in Gyeonggi, 45.0% in Gyeongnam, 16.7% in Jeonbuk, and 12.2% in Jeju. The I-ELISA methodology developed in this study was shown to have considerable sensitivity and specificity through a comparison with HI and the SN tests. Therefore, it might be one of convenient methods for screening a large number of samples in various fields.
Animals ; Antibodies, Viral/blood ; Antigens, Viral/immunology ; Encephalitis Virus, Japanese/immunology/*isolation&purification ; Encephalitis, Japanese/blood/immunology/*veterinary/virology ; Enzyme-Linked Immunosorbent Assay/methods/*veterinary ; Female ; Hemagglutination Inhibition Tests/veterinary ; Korea ; Neutralization Tests/veterinary ; Swine ; Swine Diseases/blood/immunology/*virology

Escherichia coli (E. coli) strains were collected from young diarrheic calves in farms and field. Strains that expressed the K99 (F5) antigen were identified by agglutination tests using reference antibodies to K99 antigen and electron microscopy. The K99 antigen from a selected field strain (SAR-14) was heat-extracted and fractionated on a Sepharose CL-4B column. Further purification was carried out by sodium deoxycholate treatment and/or ion-exchange chromatography. Monoclonal antibodies to purified K99 antigen were produced by the hybridoma technique, and a specific clone, NEK99-5.6.12, was selected for propagation in tissue culture. The antibodies, thus obtained, were affinity-purified, characterized and coated onto Giemsastained Cowan-I strain of Staphylococcus aureus (S. aureus). The antibody-coated S. aureus were used in a coagglutination test to detect K99+ E. coli isolated from feces of diarrheic calves. The specificity of the test was validated against reference monoclonal antibodies used in co-agglutination tests, as well as in ELISA. Specificity of the monoclonal antibodies was also tested against various Gram negative bacteria. The developed antibodies specifically detected purified K99 antigen in immunoblots, as well as K99+ E. coli in ELISA and co-agglutination tests. The co-agglutination test was specific and convenient for large-scale screening of K99+ E. coli isolates.
Agglutination Tests/methods/*veterinary ; Animals ; *Animals, Newborn ; Antibodies, Monoclonal/*immunology ; Antigens, Surface/immunology/isolation & purification ; Bacterial Toxins/immunology/isolation & purification ; Cattle ; Cattle Diseases/*immunology/*microbiology ; Chromatography, Gel/veterinary ; Chromatography, Ion Exchange/veterinary ; Chromatography, Liquid/veterinary ; Diarrhea/immunology/*veterinary ; Electrophoresis, Polyacrylamide Gel/veterinary ; Enzyme-Linked Immunosorbent Assay/veterinary ; Escherichia coli/*immunology ; Escherichia coli Infections/immunology/*veterinary ; Immunoblotting/veterinary ; Staphylococcus aureus