American foulbrood (AFB) is caused by the bacterium Paenibacillus larvae, which is highly contagious and often lethal to honeybee broods. To control AFB, rapid diagnostic tools including those based on immunological methods are required. We produced several specific mouse monoclonal antibodies (MAbs) against P. larvae. Interestingly, a few of the MAbs were revealed to be an IgM-type antibody. To ascertain the effects of adjuvants on immunoglobulin isotype switching, BALB/c mice were immunized with various adjuvants, i.e., Freund's adjuvant (FA), Alum adjuvant, and AddaVax™ followed by the generation of hybridoma that secreted monoclonal antibodies to P. larvae. In the case of AddaVax™, all screened hybridoma clones secreted IgG-type MAbs, whereas hybridomas generated by Alum and FA secreted 91.25% (7/80) and 66.67% (11/33) respectively, IgG-type MAbs. Although the mechanism of incomplete immunoglobulin isotype switching associated with the P. larvae antigen needs further study, our results indicate that the applied adjuvants can have a significant effect on immunoglobulin isotype switching results.

Chitosan is attracting attention as a health supplement material because of its various physiological activities. In this study, sugar solution containing chitosan was fed to honey bees to induce the production of ‘chitosan fortified honey’ by their same mode of natural honey production. To accomplish this, sugar solutions containing 0.1%, 1%, 2% and 5% chitosan were fed to the honey bees. Fully inverted Chitosan-honey was harvested after feeding the chitosan in sugar solution. To investigate the anti-obesity and immune-enhancing effects of Chitosan-honey, 1% and 10% Chitosan-honey containing drinking water were administrated freely to C57BL mice. Glucosamine concentrations in serum rapidly increased to peak levels in 10 minutes (1261.0 ± 97.6 ng/ml), then decreased gradually for more than 24 hours 793.0 ± 34.7 ng/ml. There were no significant differences in weight and or splenocyte proliferative capacity among experimental mice groups. However, increased granulocytes and monocytes were observed upon flow cytometric analysis. These results suggest that Chitosan-honey could induce removal of foreign antigens. In conclusion, ‘Chitosan-honey’ developed in this study has the potential for use as a honey type dietary health supplement with the same bioactivity as chitosan; however additional research should be conducted to confirm these effects.

The object of this study was to evaluate Japanese encephalitis virus (JEV) antibody titer changes in broodmares and foals. Antibodies of 112 sera were detected by applying hemagglutination inhibition test. To the best of our knowledge, this is the first report that compares antibody titers of foals to that of their dams in order for evaluate optimal time of JEV vaccination. Most mares` antibody titers were variable. However, the highest titers in foals presented in their first month, and antibodies titers in all foals decreased gradually over time. This study provides important benchmarks that can be used to select optimum time JEV of vaccination.

Tabinidae(horseflies), which are known worldwide as important mechanical vectors of virus, bacteria, protozoans, and helminths, cause disease in humans and animals. To the best of our knowledge, reports of horseflies associated with horse farms in Korea are rare, and knowledge of the horsefly fauna in Jeju is poor. The objective of this study was to evaluate the incidence of horseflies at a horse farm. Flies were collected using traps baited with natural attractants at a large horse farm during summer (Aug.-Sep. 2011). A total of 28,339 flies from 21 traps were collected on the large horse farm in Jeju. The most abundant were non-sucking flies (25,524; 90.07%) followed by sucking flies (2,226; 7.86%) and Tabanidae (589; 2.07%). Result of species analysis of 4 Tabanidae, ranked in descending order, are as follows: T. grisenus (45.2%), T. rufidens (25.3%), T. takasagoensis (21.6%), and Hybomitra bimaculata (7.9%). Although studies on vector ecology are essential to understanding, predicting, and controlling insect-borne diseases, relatively few studies on tabanids in Jeju have been reported. This paper presents the first comprehensive collection of data on the horse fly fauna of this part of the horse concentrated region. Further research is needed to investigate pathogens on the horse of horseflies.

Equine coital exanthema (ECE) caused by equine herpes virus type 3 (EHV-3) is a sexually transmitted disease which is resulted in the failure of mating, declination of horse productivity and finally economic loss in horse industry. In this thesis, diagnosis studies on ECE have been performed in order to develop a serological diagnosis method of enzyme-linked immunosorbent assay (ELISA). ELISA has been developed to detect antibodies against EHV-3. Whole EHV-3 viruses were purified from cell culture and coated on ELISA plate, which successfully captured by anti-EHV-3 antibody in serum samples. The positive cut-off value of developed ELISA was 0.334 at OD405 using 15 negative control horse sera. The positive rate of 20 sera from ECE positive horses by PCR was 65% and the positive rate of 12 sera from ECE negative horses by PCR was 25%. The positive rate of 72 sera from horses showing clinical signs was 59.7% and the positive rate of 72 sera from horses showing no clinical signs was 13.9%. The correlation of serum positivity between broodmares and their sucklings was analysed using 12 pairs of cases (y=0.5418x—0.0158, R2= 0.4931). The data suggested that specific antibody against EHV-3 from broodmares might be transferred to their sucklings by nursing. When compared with the results of PCR, the sensitivity and specificity of ELISA were 65%, 81.8% respectively.

Seropositivity against Japanese encephalitis virus (JEV) was measured by hemagglutination inhibition test (HI) on sera from 323 horses raised in Jeju. Enzyme-linked immunosorbent assay (ELISA) method was applied for the confirmation of its availability as a tool of detecting anti-JEV antibodies in horses. The positive rate scored 50.4%. The positive rates were increased according to ages. The highest peak was shown at October. And Jeju Ponies showed higher positivity compared to thoses of Thoroughbred horses. When compared the results obtained by HI and ELISA, there was slight correlations between the two methods (r=0.7100). Besides, ELISA could discriminate between true and false positive sera by neutralizing serum specimen with JEV antigen.

Vanadium, a dietary micronutrient, has been reported to present interesting biological and pharmacological properties, including superoxide and nitric oxide scavenging effects. Low-dose ionizing radiation (LDR) is known to damage DNA and cause apoptosis of peripheral immunocytes by producing reactive oxygen species (ROS). The aim of this study was to elucidate the capacity of immune activation of Jeju water containing vanadium on immunosuppression caused by LDR. We examined the ROS production, DNA damage, cell apoptosis and proliferation of peripheral immunocytes in irradiated mice drinking different concentrations for 90 days; V0 (vanadium 0㎍/L, control), V1 (vanadium 15～20㎍/ L) and V2 (vanadium 20∼25㎍/L). Compared to V0 control where level of ROS showed tendency to increase, the ROS production was attenuated in peripheral immunocytes of irradiated mice drinking V1 and V2. DNA damage of peripheral immunocytes triggered by LDR significantly increased in mice drinking V0 compared to non-irradiated control, whereas V1 and V2 dramatically induced remission of DNA damage. On the observation of apoptosis of peripheral immunocytes, V1 and V2 showed the potency to reduce the number of apoptotic cells. On the other hand irradiated mice drinking V0 exhibited raised number of apoptotic cells. From the results obtained, we speculated that Jeju water containing vanadium (V1 and V2) has a potential role in decreasing DNA damage and apoptosis of immune cell by inhibiting ROS production. Consistent with this, Jeju water containing vanadium (V1 and V2) exhibits a capacity to enhance cell proliferation of peripheral immunocytes, which is suppressed by LDR as shown in V0 control. Collectively, Jeju water containing vanadium reduced DNA damage and apoptosis and induced the stimulatory potential on immunocytes. These results suggest that Jeju water containing vanadium sustained immune activities under immunosuppression caused by LDR.

A water purifiers for home-use has been popularly used as increasing distrust of the drinking tap water in views of safety. Besides, chlorination of drinking water can produce trihalomethanes known as a carcinogens. In general, a water purifier is known to remove risk factors such as infectious microorganisms, harmful chemicals and heavy metals. We compared the change of water components before and after purification by a water purifier and evaluated the results whether this purification system is reliable or not for safety of drinking water. The samples of water from 11 sites at the campus of Jeju National University were examined by physicochemical analyses, including concentration of sodium, potassium, chloride, residual chlorine, boron, nitrate nitrogen, sulfur, hexavalent chromium, copper, iron, aluminium, silicon, selenium, vanadium, manganese, molybdenum, nickel, arsenic, antimony, zinc, cadmium, lead, strontium. Microbiological analysis was performed by counting mesophilic bacterial colonies. Almost of all the physicochemical components after purification were shown to decrease tendency of their concentrations but not significantly differenty except that of residual chlorine. Mesophilic bacterial counts after purification were shown to increase when compared to those of tap water. All the tap water was met the acceptance of requirement of drinking water, but samples of the water after purification were failed (4 from 11). After draining generous amount of water from a purifier, bacterial counts were observed to show a decreased tendency. Bacterial colonies were not detected when the concentration of residual chlorine was higher than 0.2 ppm. Although seasonal factors and maintenance condition were not concerned in this study, higher bacterial counts in purified water could cause some problems in using water purifier for home-use. Considering the results obtained, regular maintenance and care including filter change and sterilizing the reservoir are absolutely required. A further study is required to examine where the bacteria are coming from.

Porcine reproductive and respiratory syndrome (PRRS) virus causes not only breeding disorder such as abortion, stillbirth and premature birth to pregnant sows but economic damage like high estrous return and low delivery rate. The presented study was conducted to confirm seroprevalence of PRRS in Jeju herds. PRRS positive rate was examined with pig serum from hog farms located in Jeju. Serum samples were extracted from the 11 of sow farms and 10 of hog farms, The groups were divided into 20, 40, 60, 80, 100 and older than 120 days of age and pregnant sows in hog farms. Anti-PRRSV antibody titers in sera were analyzed by ELISA. All the breeding farms and hog farms (10/10) showed PRRS positive except one breeding farm (1/11). Serological patterns determined by ELISA did not show any difference regardless of whether pigs were vaccinated or not. Nevertheless, the farms unvaccinated pigs displayed low productivity in terms of piglet loss rate and prolonged period of shipment. Therefore, vaccination against PRRSV appears to be a crucial factor in sanitary management of hog farms. Taken together, since PRRSV was spread widely in Jeju already, stabilization of sows by PRRS vaccination after adapting PRRSV free sow by all-in-all-out method in farms is recommended for the control strategy for PRRS.

A screening method has been developed for detecting sulfamethazine(SMZ) contamination of meat or feeds by using horseradish pero×idase (HRP) labeled protein A (Prot A-HRP)and an indirect competitive enzyme-linked immunosorbent assay(ELISA). The assay is based on competitive binding of guinea pig anti-SMZ with SMZ in sample and SMZ-gelatin con$lt;jugate(SMZ.GEL) followed by the uptake of prot A-HR,P onto polystyrene microwell plate coated with SMZ.GEL. Percent binding B/Bo × 100) was calculated from the absorbance in the absence (BO) and presence (B) of SMZ. By the sandard curve prepared by plotting log(SMZ) vs percent binding of each lmown reference solution, the detection limit was 1.0 ppb or leas. Cross reaction with sulfadimethoxine, sulfaguaniding, sulfamerazine, sulfamthoaypyridazine, sulfanilamide, aulfisomidine and aulfisoxazole were not observed. But sulfamerazine crosareacted in the test. The EC-50 value (concentration causing 50% inhibition of color development compared with blank) of sulfamerazine was 2.0 ppm. Further quality control will make the ELISA system ideal for the detection of SMZ in meat or feeds.