Biofilm has been described as a barrier, which produced by microorganisms to survive and protect themselves against various environments, like antibiotic agents. Staphylococcus spp. is a common cause of nosocomial and environmental infection. Thirty-six and thirty-five Staphylococci were isolated from animals and air, respectively. Based on the biofilm forming ability of the bacterium reported in our previous report, relationship between biofilm formation and antibiotic-resistance was investigated in this study. Regarding antibiotics susceptibility, cefazolin was the most effective agent to the bacteria. Strong biofilm-forming Staphylococcus spp. isolates might have a higher antibiotic resistance than weak biofilm isolates regardless of the presence of antibiotic resistance genes (p less than 0.05). This result suggested that the chemical complexity of the biofilm might increase the antibiotic resistance due to the decrease of antibiotic diffusion into cells through the extensive matrix.

Bovine enteroviruses (BEVs) were separated into two groups, BEV-1 and BEV-2. BEVs, found in cattle worldwide, usually cause asymptomatic infections and are excreted in the feces of infected animals. Antibodies against BEV have been found in different species including human, cattle, sheep, goats, dogs, horses and monkeys in the world. This study aimed to investigate prevalence of the neutralizing antibodies for BEVs in human and animals in Korea. Antibodies against BEV-1 in humans, cattle, pigs, goats, horses and dogs were shown to be 46.8%, 48.3%, 70.6%, 11.5% and 6.3% respectively. Also, antibodies against BEV-2 were shown to be 98.7%, 68.1%, 89.2%, 59.4%, 9.4% and 96.9% respectively. We found that the neutralizing antibodies against these viruses are common in Korea. The prevalences of antibodies against BEV-1 were lower than those against BEV-2 in humans and in all animals except horses. These results showed that the BEV is considered endemic in cattle in many regions in Korea.

After the original identification of canine parvovirus (CPV) type 2 (CPV-2) in 1978, new antigenic variants such as CPV-2a, CPV-2b and CPV-2c have become widespread in the most countries. In this study, the genetic analysis of canine parvovirus was investigated in a total of 13 CPV vaccines, which have been licensed in Korea since late 1980s, and a field isolate of CPV from a dog with CPV infection clinical symptom. The partial VP2 gene of CPV was amplified and sequenced from 13 vaccine strains and one field isolate. The results showed that of the 13 vaccine strains, 10 strains belong to the CPV-2, 2 strains to CPV-2b, the remaining and one isolate to CPV-2a type, respectively. Several mutations of amino acids were detected at residues of the critical region of the commercial vaccine strains. These data suggest that new type of vaccines containing CPV-2a or CPV-2b/2c type may be required for the better prevention of new CPV infection in dog population in Korea, because CPV-2 contained in most licensed vaccines has been replaced by antigenic variants designated CPV-2a or CPV-2b/c in the worldwide dog population.

A 6-year-old, neutered male, Schnauzer was presented with a one year history of weight loss and exercise intolerance. Physical examination revealed abdominal distention and ecchymosis on the abdominal skin. CBC and serum chemistry profiles revealed anemia and increased serum liver enzymes. Postmortem examination revealed primary hepatic hemagiosarcoma. The tumor had extended to the mesentery and diaphragm, but distant metastasis was not found. This case report describes primary hepatic hemangiosarcoma which is very rare in a dog.

The aim of the present study was to determine the acute and subacute potential of trichlorfon in guppies (Poecilia reticulata). We first defined the 24h median tolerance limit (TLm∧24h) of the fish to trichlorfon. Guppies were then treated with TLm∧24h and 1/10 TLm∧24h trichlorfon concentrations to evaluate of any histological alterations occurred. The TLm∧24h value of trichlorfon was 11 ppm. This concentration resulted in acute toxicity to the gills and kidneys with edema, hyperplasia of the gill lamellae, and vacuolated degeneration and necrosis of renal tubular cells. In the case of subacute toxicity using a 10-fold dilution of the TLm∧24h value (1.1 ppm), no behavioral changes, external lesions or histopathological changes were observed. Therefore, safe concentration of trichlorfon might be 1.1 ppm in guppy for controlling parasitic infections.

Bovine mastitis is an important disease causing serious economic loss in dairy production and food poison in public health. Escherichia coli and Staphylococcus aureus are the major causative agents of bovine mastitis. These bacteria were found in milk and environmental condition such as feces, water, soil and so on. Bovine mastitis causative micro-organisms can survive in 1-2 weeks in feces and bed complexes. Low level of percentage of water content (PWC) of feces and bed complexes can reduce the spreading of bovine mastitis incidence from environmental contamination. In this study, we developed the fecal dehydrating system and determined the elimination rates of bovine mastitis causative agent from feces and bed complexes. To develop the fecal dehydrating system, the screw pressurized dehydrating system was used and the maximum rate of dehydrating was reached to 52% PWC using 90% PWC (wet base) of fecal and bed complexes. The elimination rates of the dehydrating system for E. coli and S. aureus were reached at 41.19±7.84% to 62.55±8.71% in various percentages of PWC of feces and bed complexes (80, 85 and 90%). These results suggested that the application of fecal dehydrating system would reduce can exposure of dairy cattle to bovine mastitis causing agents contaminated feces and bed complexes, and can be used for environmental bovine mastitis control avoiding misuse or abuse of chemical disinfectants and antibiotics in dairy farm.

This research aimed to investigate the time-course effect of epichlorohydrin (ECH) on epididymal histopathology in Sprague-Dawley rats. Twenty-four male rats were randomly assigned to four groups with 6 rats in each group and were administered a single oral dose of ECH (70 mg/kg) or its vehicle. Six animals each were sacrificed on days 0 (control), 1, 2, and 7 after treatment. During the study period, clinical signs, body weights, reproductive organ weights, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology were examined. No treatment-related effects on body weights and reproductive organ weights were noted at any time point. On the contrary, sperm motility decreased slightly on days 1 and 2 after treatment and then decreased significantly on day 7 after treatment. The first signs of histological changes were the appearance of cell debris in the ducts and vacuolization of the epithelial cells observed in the proximal caput epididymis on day 1 after treatment. The incidences and grades of the histological changes including cell debris in the ducts, epithelial vacuolization, oligospermia, and epithelial disruption increased on day 2 and then decreased slightly on day 7 after treatment. These results show that a single oral dose of 70 mg/kg ECH to male rats results in cell debris in the ducts and vacuolization of the epithelial cells in the proximal caput epididymis, followed by reversible oligospermia, epithelial disruption, and decreased sperm motility.

A dead stray cat was necropsied for zoonotic feline disease monitoring. Grossly, there were no specific lesions. Major microscopic lesions included lymphocytic meningoencephalitis, malacia, and tissue cysts in the cerebral and cerebellar cortex. The size and shape of tissue cysts were identical to those of Apicomplexa including Toxoplasma (T.) gondii. Bradyzoites in the tissue cyst were strongly positive for T. gondii by immunohistochemistry. Electron microscopy revealed that bradyzoites within the tissue cyst were similar to the morphological features of T. gondii. Fresh tissue samples were examined by a polymerase chain reaction assay and resulted in a specific band of T. gondii only in the brain. Based on the results, this case was diagnosed as toxoplasmosis. This is the first case of toxoplasmic meningoencephalitis in a cat in Korea.

Aujeszky's disease (AD) is a respiratory, infectious viral illness associated with high mortality, especially in neonatal piglets and has frequently been considered an economically important disease in many endemic countries. Although AD is still occurring in a geographically defined region in Korea, little attention has been paid to the economics of AD. In this study, partial budget technique was used to develop a simulation model to measure financial losses following the disease epidemic in a swine operation utilizing stochastic or deterministic parameters from the literatures and the index case herd of AD occurred in 2005, where available and applicable. For the infected case herd with a 12500-pig, the total economic loss for this operation was estimated to be about 199 million Korean won (95% confidence interval [CI] 148,645,000-250,741,000). Given net loss due to death of a pig at sow level was 119,000 won, total loss for the case herd with 1200 sows accounted for 143 million won (95% CI 92,599,000-193,729,000). The net loss of the death of one pig at growing and fattening level resulted in loss of 46,000 won (95% CI 40,000-53,000) and 126,000 won (95% CI 122,000-131,000), respectively. Taking into account for the number of pigs raised in the case herd, total loss amounted to 8 million won (95% CI 7,167,000-9,347,000) and 12 million won (95% CI 11,959,000-12,891,000), for growers and fatteners, respectively, assuming 63% of saved feed intake when a pig dies halfway through the respective period. Under the model's assumptions, suckling pig mortality was the major factors of loss in estimating the economic consequences (approximately 71.8% of the total loss). The high economic losses of a herd infected with AD suggest that the effective and region-specific control measures should be implemented in disease endemic foci.

The pathogenicity and acute toxicity of Lactobacillus (L.) pentosus PL11 from eel (Anguilla japonica) were investigated using male and female Sprague-Dawley rats. The pathogenicity of L. pentosus PL11 was examined after treating the rats with 10∨11 CFU/mL, 10∨9 CFU/mL or 10∨7 CFU/mL doses of L. pentosus PL11 culture or 0.85% NaCl (Control) intragastrically. For acute toxicity studies, rats were treated with dried culture broth of L. pentosus PL11 at doses of 5,000 mg/mL, 2,500 mg/mL, 1,250 mg/mL or 625 mg/mL or Lactobacilli MRS broth (Control), and clinical signs or mortalities were monitored for two weeks. The results of the present investigation revealed no mortalities or obvious clinical signs in rats administered with the live bacterial cultures or dried culture broth at any investigated dose level. Also, no significant differences were observed in net body weight gain, gross pathological findings, feed and water consumption and body temperature among the different treatment groups and between the treated and control rats. It can be concluded from the above findings that L. pentosus PL11 is a safe probiotic strain with potential as feed additive to increase the feed efficiency or health of fish.