• Journal of Microbiology and Biotechnology
• /
• v.28 no.12
• /
• pp.2095-2105
• /
• 2018

In our previous studies, we have identified several in vivo-induced antigens and evaluated their potential as subunit vaccine candidates in a murine model, in which the recombinant protein GalT showed the most potent immunogenicity and immunoprotective efficacy against Actinobacillus pleuropneumoniae. To exploit a more efficient way of delivering GalT proteins, in this study, we employed the widely studied E. coli outer membrane vesicles (OMVs) as a platform to deliver GalT protein and performed the vaccine trial using the recombinant GalT-OMVs in the murine model. Results revealed that GalT-OMVs could elicit a highly-specific, IgG antibody titer that was comparable with the adjuvant GalT group. Significantly higher lymphocyte proliferation and cytokines secretion levels were observed in the GalT-OMVs group. 87.5% and 50% of mice were protected from a lethal dose challenge using A. pleuropneumoniae in active or passive immunization, respectively. Histopathologic and immunohistochemical analyses showed remarkably reduced pathological changes and infiltration of neutrophils in the lungs of mice immunized with GalT-OMVs after the challenge. Taken together, these findings confirm that OMVs can be used as a platform to deliver GalT protein and enhance its immunogenicity to induce both humoral and cellular immune responses in mice.

• Korean Journal of Veterinary Service
• /
• v.22 no.2
• /
• pp.121-128
• /
• 1999

The present study was conducted to investigate the incidence of pneumonic lesions with special regard to enzootic pneumonia and the microbiology of pneumoic lungs from 544 slaughter pigs during the period from October 1995 to September 1996. The incidence of enzootic pneumonic lesion was 76.3% (41s/s44) and pleurisy was detected from 7.9% of slaughter pigs. Seasonal prevalence of pneumonic lesions in slaughter pigs were in order of prevalence of 82.9% in spring, 76.8% in winter, 74.8% in autumn and 69.0% in summer, respectively. Pasteurella multocida, Streptococcus sp, Str suis, Corynebacterium sp, Actinobacillus pleuropneumoniae, Hemophilus parasuis, and Klebsiella pneumoniae were detected in order of prevalence from 16.9%, 15.9%, 7.5%, 6.0%, 1.4%, 1.0% and 0.5% of 415 pneumonic lungs, respectively. P multocida were susceptible to oxytetracycline, polymyxin-B, streptomycin, and vancomycin, while the majority of them were resistant to amoxicillin, ampicillin, cephalothin, kanamycin, and penicillin-G. Str suis were susceptible to amoxicillin, ampicillin, cephalothin, penicillin-G, although the majority of them were resistant to erythromycin, oxytetracycline, streptomycin, vancomycin. A pleuropneumoniae were susceptible to ampicillin, and cephalothin, but the majority of them were resistant to oxytetracycline.

• Korean Journal of Veterinary Service
• /
• v.19 no.2
• /
• pp.126-138
• /
• 1996

Lungs from 109 slaughter pigs with gross lesions indicating enzootic Pneumonia of pigs(EPP) and 16 grossly normal lungs, all originating from seven different herds, were subjected to microbiological examinations. The microbiological studies were included both bacterial and mycoplasmal culture. From lungs of 125 slaughter pigs, 87.2% pigs were pneumonia lesions alone or complexly Mycoplasma spp., pasteurella multocidu(p. multocida), Streptococcus spp., and Actinobacillus pleuropneumoniue(A. pleuropneumoniae) were detected in 39.4%, 42.2%, 13.8%, and 3.7% of the pneumonic lungs, respectively. P. multocida was the most frequently isolated organism in pneumonic lungs. Mycoplasmas not isolated organism in 33.9% the pneumonic lungs even If [here are gross lessions mycoplasmas. The amounts of pneumonia in lungs with Mycoplasma spp. alone, a concurrence of Mycoplasma spp. and P. multocida, p. multocida alone, a concurrence of P. multocida and A. pleuropneumoniae, and a concurrence of Mycoplasma spp. and A pleurdpneumoniae were 10.1%, 22.7%, 18.7%, 25%, and 30%, respectively These findings indicated that p. multocida might be involved in the pathogenesis of pneumonia in slaughter pigs. Mycoplasma spp. was also, in this study, associated with higher frequency of pneumonia. The frequency of pigs snout lesion grade 0∼5 inclusive were 27.2%, 28%, 19.2%, 16%, 6.4%, and 3.2% from 125 slaughter pigs. 32(25.6%) pigs were positive and 13~30% in the pigs from seven herds were found to be infected with atrophic rhintis (AR). A total of 46 P. multocida strains In pneumonic lungs were further characterized by capsular serotyping and testing for production of dermonecrotic toxin. 42(91.3%) of strains were capsular A and 4(8.7%) were type D. Out of the type A and type D strains, 86% and 75% were toxigenic, respectively.

• Food Science and Biotechnology
• /
• v.27 no.6
• /
• pp.1823-1831
• /
• 2018

This study examined the efficacy of Atractylodes macrocephala Koidz (AMK) protein and polysaccharide extracts as adjuvant or adjuvant booster when given together with porcine pleuropneumonia vaccine. Experimental mice (n = 5/group) were subcutaneously immunized with $25{\mu}g$ ApxIIA #3 antigen, a target protein against A. pleuropneumoniae, together with alum and/or various concentrations ($0-500{\mu}g$) of the AMK extracts, while the control group received PBS only. Immunization with ApxIIA #3 antigen increased the antigen-specific IgG titer and this increase was enhanced in the immunization together with AMK protein, but not polysaccharide extract. Supplementation of AMK protein extract exhibited dose-dependent increases in the antigen-induced protective immunity against A. pleuropneumoniae challenge and in the lymphocyte proliferation specific to the antigen. Glycoproteins present in the AMK extract were the active components responsible for immune response induction. Collectively, the present findings suggest that AMK glycoproteins are useful as immune stimulating adjuvant or adjuvant booster.

• Korean Journal of Veterinary Research
• /
• v.40 no.3
• /
• pp.551-561
• /
• 2000

Swine respiratory diseases have induced severe economic losses in swine industry worldwide. Several methods have been developed and applied to prevent and control the disease. However, those are still problematic in swine industry. Recently, the use of egg yolk antibodies with several advantages was introduced and applied to control diseases in animal as well as human. As the first step of the use of egg yolk antibodies in the control of the swine respiratory diseases, we investigated the immunogens of the causative agensts of the diseases and immune response in egg yolk of hens immunized with them. Bacterial antigens prepared from Bordetella bronchiseptica, Pasteurella multocida 3A and 4D, and Actinobacillus pleuropneumaniae serotype 2 and 5 were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western blot and toxicity test in mice. The antigens were injected into laying hens in order to produce antibodies against them in egg yolk. After chickens were immunized three times in 2 weeks interval, the profile of antibody production was examined by ELISA. The production of antibody in egg yolk was started in 2 weeks after the first injection, reached peak in 6-8 weeks and maintained until 12 weeks. Of two adjuvants used in this study, ISA70 was more effective than aluminum hydroxide gel in enhancing immunogenecity, laying rates and safety in hens. These results suggested that egg yolk antibodies could be a good source for production of antibodies specific to pathogenic bacteria inducing respiratory diseases of swine.

• Korean Journal of Veterinary Service
• /
• v.32 no.1
• /
• pp.27-32
• /
• 2009

We studied the seroprevalence of four respiratory pathogens in Korean swine farms located in Chungnam, Chungbuk, Gyeongnam and Gyeongbuk provinces during the period of spring of 2007 to winter of 2008. Serological tests were performed using commercial ELISA kits. A total of 530 serum samples were tested for the antibodies against porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (M. hyo) and Actinobacillus pleuropneumoniae (APP). Seroprevalence for four respiratory pathogens were estimated by ELISA-positive rates of the submitted samples. The overall seropositive rates of PRRSV, APP, M. hyo and PCV2 were 32.6%, 10.6%, 38.4% and 88.5%, respectively. By production stage, the seropositive rate for PRRSV was highest in nursery pig populations (46.2%). In contrast, the highest seropositive rates of APP and M. hyo were observed in sow and growing pigs. However, the seroprevalence of PCV2 was ranged from 85.7% to 89.6%, showing no significant difference among the production stages. In the seroprevalence by season, PRRSV, APP and M. hyo infections revealed typical seasonal patterns that the peaks of the seropositive rates were observed between early winter and late spring. In case of PCV2, no particular seasonal patterns were noticed. The pig herds in Gyeongbuk province where PMWS was endemic during the period of survey showed the highest seropositive rates for PRRSV (44.6%), M. hyo (47.5%), and PCV2 (92.7%). Seropositive rates for APP of four provinces were approximately 10%. These results might be valuable for control and prevention of the respiratory diseases and helpful to define strategies related to vaccine applications.

• Korean Journal of Veterinary Service
• /
• v.39 no.4
• /
• pp.231-237
• /
• 2016

The present study was conducted to investigate the lesion of red internal organs in slaughtered pigs and provided assistant data for pig farms. During March to December 2015, a total of 1,160 lung samples out of 58 herds were collected randomly from pigs slaughtered in Jeonbuk province. In addition, 290 hilar lymph nodes from pig with pneumonic lung lesion (5 samples per herd) were screened for selected viral and bacterial pathogens. Gross lesions of lungs such as swine enzootic pneumonia (SEP), pleuritis, pleuropneumonia, pericarditis and liver white spots were examined. The overall prevalence of SEP was 64.3% (746/1,160). In the analysis of seasonal prevalence, there was an increase of occurrence during the spring months (287/400, 71.8%) and decrease during the fall months (93/200, 46.5%) among the whole herds. The mean number of SEP score per pig was $1.20{\pm}1.28$. The prevalence of pleuropneumonia, pleuritis, pericarditis, and milk spot was 25.5% (296/1,160), 44.1% (512/1,160), 3.8% (44/1,160) and 17.6% (204/1,160), respectively. The most frequent region with lung lesion was diaphragmatic lobes (left 17.1%, right 17.3%). In the detection of viral pathogens by PCR, porcine circovirus type2 (PCV2) was positive in 86.9% (252/290), while porcine reproductive and respiratory syndrome virus (PRRSV) was not detected, In the case of bacterial pathogens, 50 microorganisms were isolated by PCR and/or microbiological test. The most frequently isolated bacteria was Streptococcus suis (20, 34.4%), followed by Pasteurella multocida (17, 29.3%), Streptococcus spp. (11, 3.4%), Actinobacillus pleuropneumoniae (2, 8.9%).

• Journal of Plant Biotechnology
• /
• v.37 no.3
• /
• pp.313-318
• /
• 2010

To develop edible vaccines for swine, the embryogenic calli (type II) derived from HiII genotype were inoculated with A. tumefaciens strain C58C1 containing the binary vector pMYV611, 613, 616, and V621, 622 and 623 respectively. Six of those vectors carry nptII gene which confers resistance to paromomycin and apxIIA gene producing ApxII toxin which is generated in various serum types of A. pleuropneumoniae as a target gene. The 4,120 callus clones for pMYV611, 5,959 callus clones for pMYV613, 7,581 callus clones for pMYV616, 52,329 callus clones for V621, 48,948 callus clones for V622, and 56,188 callus clones for V623 were inoculated. The frequency of positive response clone was confirmed into range of 2.3% - 4.4% for each vectors by NPTII ELISA kit assay, and the selected callus clones of them were finally 3 callus clones from pMYV611 (0.07%), 4 callus clones from pMYV613 (0.07%), 2 callus clones from pMYV616 (0.03%), 51 callus clones from V621 (0.1%), 72 callus clones from V622 (0.15%), and 102 callus clones from V623 (0.18%) respectively. From the selected callus clones of each binary vector, the integration of the apxIIA gene into maize genome was detected from 2 plants of pMYV613 and 2 plants of V623 by Southern blot analysis.

• Journal of Veterinary Clinics
• /
• v.9 no.2
• /
• pp.401-406
• /
• 1992

For the purpose of effective treatment and prevention of porcine respiratory diseases, Enrofloxacin(Baytril premix) was administered in the feed to trial herd occurred sporadically the respiratory diseases and then a serious investigation was carried out on the therapeutic effect, weight gain, feed conversion rate and lung lesion scoring. The results obtained were as follows, 1. The grower pigs which were administered with Baytril premix for 10 days gained the average body weight of 31kg for 33 days compared to 20.5kg of control group(p<0.05). Also drastical improvement of feed conversion rate(p<0.05) and disappearance of clinical signs were approved. 2. Average scorings of lung lesions were 7.92% in the medication group and 15.8% in the control group respectively. 3. Respiratory diseases outbreaked in the trial farm were pleuropneumonia caused by Actinobacillus (Haemophilus)pleuropneumoniae, Mycoplasmal pneumonia and Pasteurellosis.

• Journal of Veterinary Clinics
• /
• v.11 no.2
• /
• pp.507-516
• /
• 1994

The purposes of this investigations were survey of the occurred bacterial diseases, development of new animal health drug, guidance to formers on the treatment and control methods of diseases. Some series of investigations have been carried out by microbiological, pathological and serological examinations. The results could be summarized as follows. 1. A total of 953 cases of outbreaked swine diseases have been diagnosed in Clinical pathology laboratories, Bayer Vet Res Institute during 8 years (from 1986 to 1993). The high incidence diseases were colibacillosis, pleuropneumonia, streptococcal infection and pasteurellosis in decreasing order. 2. Pleuropneumonia caused by Actinobacillus pleuropneumoniae was the most important respiratory diseases and pasteurellosis by Pasteurella multocide could be confirmed in several cases. 3. Actinobacillus pleuropneumoniae 50 strains were isolated and identified by biochemical and serological tests. In serotyping test, 22 isolated strains were serotype 5, 21 strains as serotype 2, each 2 strains as serotype 3 and 7 by the coagglutination test. 4. Colibacillosis and edema discase caused by Escherichia coli has been the most predominant outbreaked disease in this investigations. The 100 isolates of E coli strains were sensitive to amikacin, colistin, enrofloxacin, gentamycin and trimethoprim -sulfamethoxazole. 5. Swine erysipelas caused by Erysipelothrix rhusiopathiae was confirmed 25 cases as acute septicemic forms. Isolates of E rhusiopathiae were highly sensitive to ampicillin, cephalothin, enrofloxcin, penicillin and tetracycline. 6. The 49 cases of hemorrhagic and necrotic enteritis in piglets were observed and 13 strains of Clostridium perfringens could be isolated and confirmed by biological and serological test. Isolates of Clostridium perfringens type C were highly sensitive to ampicillin, cephalothin, enrofloxacin, penicillin and trimethoprim- sulfamethoxazole. 7. The 14 strains of Streptococcus suis type II could be isolated from meningitis of piplets. 8. Polyserositis caused by Haemophilus parasuis and salmonellosis were observed and confirmed. Also Corynebacterial infections and several parasitosis have been also observed in this investigations.