• Korean Journal of Veterinary Research
• /
• v.28 no.2
• /
• pp.331-337
• /
• 1988

This paper dealt with the distribution of Salmonella (S) infection on 4 herds in Kyungju and Taegu during the period from May to October 1986. Isolated Salmonella were examined for serotypes, antimicrobial drug resistance and detection of R plasmid. The results obtained were summarised as followings: 1. Of total 4.622 samples from 4 herds, 67 Salmonella were isolated from 51 samples(1.1%), and their serovar strains were S typhimurium 6, S derby 5, S infantis 4, S bareilly 4, S dublin 3, S anatum 2, S montevideo 2 and untypable 41. 2. The isolation rate of Salmonella was higher in summer and autumn. 3. Of the 67 strains examined, 45 (67.2%) were resistant to one or more antibiotics, such as ampicillin (Am), cephalothin (Ce), chloramphenicol (Cm), rifampicin (Rf), sulfadimethoxine (Su), and tetracycline (Tc), and higher resistant to Sm (40.2%), Ce (31.3%), Am (23.9%). 4. Of the 45 resistant Salmonella strains, 44 (97.8%) harbored conjugative R plasmids and the transfer frequency of Sm (100%), Ce (95.2%), Tc (91.0%) and Su (80.0%) resistance was much higher than that of the other drug resistance. 5. The most common resistant patterns were Sm, Ce, AmCeCmSmSuTc, and AmCe. 6. In 4 herds, the incidience of drug resistance was 57.7%~100% and transfer frequency of conjugative R plasmid was 96.1%~100%.

• Journal of Veterinary Science
• /
• v.24 no.4
• /
• pp.58.1-58.25
• /
• 2023

Porcine epidemic diarrhea virus (PEDV) has posed significant financial threats to the domestic pig industry over the last three decades in South Korea. PEDV infection will mostly result in endemic persistence in the affected farrow-to-finish (FTF) herds, leading to endemic porcine epidemic diarrhea (PED) followed by year-round recurrent outbreaks. This review aims to encourage collaboration among swine producers, veterinarians, and researchers to offer answers that strengthen our understanding of PEDV in efforts to prevent and control endemic PED and to prepare for the next epidemics or pandemics. We found that collaboratively implementing a PED risk assessment and customized four-pillar-based control measures is vital to interrupt the chain of endemic PED in affected herds: the former can identify on-farm risk factors while the latter aims to compensate for or improve weaknesses via herd immunity stabilization and virus elimination. Under endemic PED, long-term virus survival in slurry and asymptomatically infected gilts ("Trojan Pigs") that can transmit the virus to farrowing houses are key challenges for PEDV eradication in FTF farms and highlight the necessity for active monitoring and surveillance of the virus in herds and their environments. This paper underlines the current knowledge of molecular epidemiology and commercially available vaccines, as well as the risk assessment and customized strategies to control PEDV. The intervention measures for stabilizing herd immunity and eliminating virus circulation may be the cornerstone of establishing regional or national PED eradication programs.

• Korean Journal of Veterinary Research
• /
• v.18 no.2
• /
• pp.61-67
• /
• 1978

The detection of Bordetella bronchiseptica which is supposed to be an agent of the infectious atrophic rhinitis of swine, is likely to receive more attention in the future as the pork industry comes to realize that eradication of this infection from breeding herds is a practical possibility. Experiments described here were carried out to establish the rapid plate agglutination test for the detection of the infectious atrophic rhinitis of swine in the field using the criteria of antigen preparation, effects on the antigenecity after storing of the antigen and reaction appearing time. Also, the agglutinabilities between the plate and tube method were compared and the degree of pathological lesions were recorded in relation to tube agglutination titers. Obtained results were as follows: 1. No differences were noted in the agglutinabilities on the plate agglutination test between the treatments in antigen preparation-formolized, merthiolate-killed and living organism. 2. The agglutinability of the antigens did not show any significant changes until 10 weeks of storage at 4 C; however, after 10 weeks of storage, non-specific reaction was observed with the HPCD control sera. 3. The results of the plate and tube agglutination tests were not comparable but the effective use of the plate method in Bordetella bronchiseptica eradication programs in pigs especially in the sow is stressed as a screening test.

• Journal of Life Science
• /
• v.19 no.5
• /
• pp.615-619
• /
• 2009

The present study was conducted to investigate the species-specific gene detection and antimicrobial susceptibility of Pasteurella (P.) multocida isolated from pneumonic lung lesions of Youngnam swine herds during the period from July 2006 to September 2007. A total of 91 (36.3%) strains of P. multocida were isolated from 251 pneumonic lung lesions. The species-specific P. multocida gene was detected at 460 bp amplicons by PCR. The P. multocida tested was susceptible to florofenicol (93.4％), amikacin (91.2％), cephalothin (87.9％), cefoxitin (84.6％), ofloxacin (80.2％) and norfloxacin (65.9％) in 27 antimicrobial susceptibility tests. Most of strains were resistant to more than 5 drugs.

• Korean Journal of Agricultural Science
• /
• v.42 no.3
• /
• pp.215-222
• /
• 2015

This paper sketches the strategies and designs for monitoring system of swine genetic improvement. The system should reflect every side of pig production. The system leads us to assess the efficiency of pig production and the scope of the system includes not only nucleus, multiplying and commercial herds, but also packing and processing sectors. For more accurate statistics, data for this monitoring system must be collected from all above mentioned areas, but not by random sampling. Futhermore, data analysis results including seedstocks and distribution information of genetic trend should be included in the system. The schema of knowledge database system could be employed in the system. The monitoring system in the final destination would unify the systems derived from various sources and provide any solution in swine industry including pig breeding.

• Food Science of Animal Resources
• /
• v.30 no.1
• /
• pp.62-65
• /
• 2010

Salmonellosis is one of the most important wasting diseases that leads to economic damage in the swine industry. Many risk factors have been reported to increase the spread of Salmonella infection; therefore, it is important to understand how to treat the risk factors of Salmonella to effectively prevent salmonellosis in commercial pig farms. To accomplish this, we conducted a study to determine if the seasons and porcine production stages affected the serological response to Salmonella in Korea. A total of 1,592 serum samples submitted to the School of Veterinary Medicine of Kangwon National University between Jan. 2001 and Dec. 2004 from commercial farms were tested by ELISA. The overall apparent seroprevalence of salmonellosis was 38.1% (95% CI, 38.0-38.2), while the prevalence of Salmonella according to seasons and production stages ranged from 17.9% to 62.8% for the former (24.6% in spring, 17.9% in summer, 38.5% in autumn, and 62.8% in winter) and from 16.1% to 68.3% for the latter (17.9% in suckling pigs, 16.1% in weaning pigs, 37.50% in growers, 41.9% in finishers, 48.0% in gilts, and 68.3% in sows). In this study of seroprevalence by production stage, most pigs were naturally infected by Salmonella during the weaning stage. Also, seroprevalences were found to have a seasonal pattern in which most pigs were infected in autumn to winter.

• Journal of Veterinary Science
• /
• v.23 no.5
• /
• pp.32.1-32.11
• /
• 2022

Background: Classical swine fever (CSF) is a severe infectious disease of pigs that causes significant economic losses to the swine industry. Objectives: This study developed a solid-phase blocking enzyme-linked immunosorbent assay (spbELISA) method for the specific detection of antibodies against the CSF virus (CSFV) in porcine serum samples. Methods: A spbELISA method was developed based on the recombinant E2 expressed in Escherichia coli. The specificity of this established spbELISA method was evaluated using reference serum samples positive for antibodies against other common infectious diseases. The stability and sensitivity were evaluated using an accelerated thermostability test. Results: The spbELISA successfully detected the antibody levels in swine vaccinated with the C-strain of CSFV. In addition, the detection ability of spbELISA for CSFV antibodies was compared with that of other commercial ELISA kits and validated using an indirect immunofluorescence assay. The results suggested that the spbELISA provides an alternative, stable, and rapid serological detection method suitable for the large-scale screening of CSFV serum antibodies. Conclusions: The spbELISA has practical applications in assessing the vaccination status of large pig herds.

• Korean Journal of Veterinary Research
• /
• v.52 no.1
• /
• pp.39-43
• /
• 2012

A multiplex PCR was developed for the simultaneous detection and differentiation of Mycoplasma (M.) hyopneumoniae and M. hyorhinis in clinical samples. Improved sensitivity is advantage of this technique over the previously reported multiplex assay. It was capable of detecting as little as 125 fg genomic DNA from M. hyopneumoniae and 62.5 fg genomic DNA from M. hyorhinis. Application of this multiplex PCR method to field isolates showed that M. hyopneumoniae and M. hyorhinis were present in 29% (107 of 370) of lung specimens and no mycoplasmas were detected in 56% (208 of 370) of the slaughtered pigs' lungs. At the farm level, M. hyopneumoniae and M. hyorhinis were detected in 34 of 36 (94.4%) randomly selected farms. We conclude that this assay would prove itself a value tool for monitoring these mycoplasmal infections and both M. hyopneumoniae and M. hyorhinis have been widely spread in swine herds of Korea.

• Korean Journal of Veterinary Research
• /
• v.19 no.2
• /
• pp.153-157
• /
• 1979

The authors encountered 78 cases of pig from two swine herds with severe dermatitis, which had been fed with commercial rations. Main clinical signs were hard crust formation or erythema and papules on the skin and retarted growth. The skin lesions were visible on the limb joints in all cases. In some cases, however, crusts occurred on the tail, perineum, hip, ear, back, or neck. In one case the entire body surface was covered with thick crust. No mites were detected on the microscopic examination of skin scrapings. Histological examination of biopsies skin specimens taken from the lesions revealed typical parakeratotic changes: the cornified layer of epidermis was irregularly inreased in thickness and contained numerous nuclei. The provision of dietary supplementation with zinc sulfate and soybean oil for 10 days showed marked curative effect.

• Korean Journal of Veterinary Service
• /
• v.33 no.1
• /
• pp.67-74
• /
• 2010

To reduce an economic loss by swine disease, this study was designed to provide helpful data which are particularly useful for each individual farm. From february to December 2009, a total of 18,173 slaughter pigs (612 herds) were randomly sampled, which were produced just in southern region of Gyeonggi-do. We examined all of them for the slaughter lesions of 8 kind diseases such as swine enzootic pneumonia (SEP), pleuritis (PL), pleuropneumonia (PP), white milk spot in liver (WMS), papular dermitis (PD), pericarditis (PC), ileitis (IL) and peritonitis (PT). Twenty four percentages (4431/18173 pigs) of the examined pigs had no lesions about 8 kind diseases. Among the pigs with lesions, the numbers of the pigs with just one lesion were 7,637(42%), followed by 4,551(25%) pigs with 2 lesions. Average prevalence of pigs were 56.5% (10288/18173 pigs) in SEP, followed by 34% in PL, 12.4% in PP, 10.1% in WMS, 6.1% in PD, 4.7% in PC, 0.1% in IL and PT, respectively. Each prevalence of SEP, PL, PP and PD was higher in spring than in winter, respectively (P<0.01). Among the pigs (n=6,105) with 2 or more than 2 kinds of lesions the top (55.5%) was the pigs with SEP and PL, and the second was 1,179 (19.3%). Swine enzootic pneumonia was considered as one of the more likely risk factors for initiation or/and acceleration of other diseases such as PL, PP, WMS and PD. The lesion of SEP was relatively severe since the pigs with late stage were more (7,277 pigs) than those with early stage.