The purpose of this study was to establish a rapid, reliable diagnostic method detecting Encephalomyocarditis virus(EMCV) RNA in formalin-fixed, paraffin-embedded tissues of EMCV naturally infected pigs by cDNA probe of EMC K3, the EMCV strain isolated from Korea. Using a biotin-labelled nick translated probe for the cDNA marker. We made up for some defects of radiolabeled method. In situ hybridization(ISH) technique, differently from theother nucleic acid hybridization methods, is able to detect the virus genome specifically in the state of the intact shapes of cells and/or tissues. We succeeded in performing the experiment to detect the EMCV within 1~2 hours usign the MicroProbeTM capaillary action system. In this study, we ovserved highly specific positive sighals of red color by staining the paraffinembedded tissue sections of naturally EMCV-infected pig organs or tissues, including brain, heart, kidney and lacrimal gland with the Fast Red TR salt/Naphtol phosphate chromogen. The results suggested that this ISH method is considered as a highly sensitive and reliable tool for molecular biologic diagnosis of the EMC viral disease.

Evaluation of the myelography was studied in miniature pigs. Radiographs and computed tomographic (CT) images of the whole spine were obtained at clinically healthy twelve miniature pigs of 4 (8.7-10 kg) and 12 (26-31 kg) months. The assessments of the spinal cord were made in accordance with the Pavlov's method and compared area ratio [at spinal cord (SC), vertebral canal (VC) and vertebral body (VB)]. The Pavlov's ratio in the cervical spine was significant larger than that of thoracolumbar in radiographic myelography. On CT myelography, the area of the spinal cord had a significant difference between the cervical and thoracolumbar spine. Among the cervical spine, the ratios of spinal cord and vertebral body (SC : VB), vertebral canal and vertebral body (VC : VB) were minimum at the level of 4th cervical spine in both ages, while maximum at the level of 6th cervical spine in both months. In case of lumbar spine, the ratios of spinal cord and vertebral body (SC : VB) were the largest at the level of 4th lumbar spine in 4 months and at the level of 3rd lumbar spine in 12 months. In addition, the ratio of spinal cord and vertebral body (SC : VB) of the cervical spinal cord was significant lower at 4 months but the lumbar spinal cord showed lower pattern at 12 months old miniature pigs.

Torque teno virus (TTV), a species of Anellovirus, is a non-enveloped single stranded DNA virus with a wide range of animal hosts. The incidence of TTV is quite ubiquitous throughout the world. A total of 235 serum samples obtained from 137 pigs and 98 cattle at slaughterhouses in Korea during April 2005 to May 2005 were tested by TTV-specific PCR as to monitor prevalence of TTV among swine and cattle. As a result, the prevalent rates of TTVs in pigs and cattle were 43.1% and 4.1%, respectively. It seems that TTV infection is quite prevalent in swine population.

Swine plasminogen is not activated by staphylokinase of Staphylococcus aureus. In this study, the activation of swine plasminogen by staphylokinase of Staph hyicus subsp. hyicus was investigated and the effect of EDTA(disodium) on plasminogen activation was also studied. When the activation of swine plasminogen by staphylokinase of Staph hyicus subsp. hyicus was examined in fresh swine plasma, swine plasminogen could be weakly activated. However, when EDTA was added to the swine plasma, plasminogen activation was markedly enhanced, but this enhancement was not observed on bovine fibrin-dog plasminogen agar plate containing EDTA. Chicken and bovine plasminogens were not activated by staphylokinase of Staph hyicus subsp. hyicus. Using fresh swine plasma agar containing 0.07% EDTA, staphylokinase activity was detected in 96.3% of Staph hyicus subsp. hyicus strains isolated from pigs and in none of the chicken and bovine strains.

A nation wide sero-epidemiological survery of porcine reproductive and respiratory syndrome(PRRS) was carried out to analyze the current status of the PRRS virus infections in the field using the indirectr immunofluorescent antibody assay(IFA) with the field isolate PL96-1. Since the first report of the antibody detection to PRRSV in 1993, the prevalence of seropositive pigs has increased dramatically and the data indicate that over 21% of the pigs and around 60% of the farms showed seropositives to the PRRS virus. A slightly higher positive rate was recognized in breeders than fattenings and it might be due to the higher age at the time of testings. No significant regionl defferences were detected in the sero-epidemiological survey. Higher sero-positive rate in growers indicatesthat PRRSV infection in the field was common after weaning(around 40 days). However, the number of seropositive pigs were declined in fattening pigs. Sows showed around 26% of sero-positive rate that there is a higher chance of continuous virus circulation in the infected farms. Low rate of sero-positivity in boars(9.8%) implies that there is high demand in proper controlmeasures to prevent virus spreading through breeding procedures such as natural or artificial insemination Therefore it was concluded that PRRSV infection in domestic swine herds is endemic and the positive rate and economic loses will be increased by spontaeous infections in naive farms.

This study was designed to quantitative assay of cellular receptor globotriosyl ceramide(Gb₃) and globotetraosyl ceramide(Gb₄) and to determine binding affinity of the receptors for Shigatoxin 2e in difference with day olds of pig. The amount of Gb₃ and Gb₄ extracted from each swine tissue were detected in order of spleen, ileocecum, kidney, and jejunum. The amount of Gb₃ and Gb₄ extracted from each swine ileocecum and jejunum in different day old swine were detected in order of 24, 6, 98, 12 and 35, but the difference of amount was not significant.

Shiga toxin-producing Escherichia coli (STEC) causes various clinical signs in human and animals, and has been indicated as a global enteropathogen with zoonotic importance. In this study, the feces of healthy pigs were collected from the slaughtered pigs of Daejon abattoir during the period from December 2001 to October 2002. Of 326 specimens, 13 STEC were confirmed by culture, PCR and colony hybridization. The isolates were further studied for toxin types, pathogenic factors, plasmid profiles, and antimicrobial resistance to characterize the genetic and toxigenic properties.

Blood samples from 622 pigs of 44 farms which were sero-positive to Mycoplasma hyopneumoniae (M. hyo) by ELISA method were collected from May 2003 to July 2004. And they were divided into 2 categories : M. hyo-vaccinated group (7 swine farms) and M. hyo-non-vaccinated group (37 swine farms). Then, each swine farm was analysed by sero-positive percentage per weeks of age. It was observed that the sero-positive percentage to M. hyo is directly proportional to weeks of age in the 44 swine farms that were selected.

This study investigated the effects of gonadotropin-releasing hormone (GnRH) vaccine on pig growth, carcass quality, and sensory perceptions of pork meat by Thai consumers. Male crossbred pigs (n = 30) were separated into three groups of 10 pigs each: boars, immunocastrated pigs, and surgically castrated pigs. The immunocastrated group was immunized at 13 and 19 weeks of age with GnRH vaccine (400 킽/dose). All pigs were slaughtered at 24 weeks of age. Blood samples were collected and testes size determined. Testes weight and back fat thickness were recorded at the time of slaughter, and meat samples were collected for sensory assessment by Thai consumers. Testosterone and progesterone concentration levels decreased significantly two weeks after the second dose of GnRH (p less than 0.05), and the GnRH antibody titer of the immunocastrated pigs was significantly high two weeks after the second dose of GnRH (p less than 0.05). GnRH vaccine significantly reduced the weight and size of testes. Thai consumers reported no significant differences in odor or flavor among meat samples from the three groups. In conclusion, immunocastration improved growth performance, removed the need for castration surgery, and avoided "boar taint" in the meat. It has also no distinct trace of the boar taint same as pork that is currently produced from physically castrated pig which is making it acceptable to consumers.

This study investigated the effects of vitamin C on oxidative stress induced by volatile anesthetics in pigs. One group of pigs was used as an anesthesia control group (group 1), and they were anesthetized with isoflurane in oxygen and saline (0.9% NaCl) was injected intravenously. The other group (group 2) was anesthetized with isoflurane and injected intravenously with vitamin C. Total oxidant status, total antioxidant status, and the oxidative stress index in group 2 were significantly different compared with those in group 1. The results showed that intravenous administration of vitamin C decreased oxidative stress during isoflurane anesthesia in pigs.