Salmonella enterica serotype Choleraesuis infection in weaned pigs: a first clinicopathological case report from Korea

Salmonella enterica serotype Choleraesuis causes swine paratyphoid, with clinical findings of enterocolitis and septicemia. However, the clinicopathological features of S. Choleraesuis infections in pigs have not been reported in Korea. We describe the pathological findings of two weaned pigs with S. Choleraesuis infections, presenting with diarrhea, cough, and sudden death. Pathological examination indicated severe necrotic colitis in pig 1 and septicemic lesions in pig 2. Multidrug-resistant S. Choleraesuis was isolated from the pigs’ lungs and intestinal contents. Further research is required for the surveillance of S. Choleraesuis infections in pigs and the virulence estimation in the S. Choleraesuis isolates.

Pathogenicity of clade 2.3.4.4 H5N6 highly pathogenic avian influenza virus in three chicken breeds from South Korea in 2016/2017

In 2016, novel H5N6 highly pathogenic avian influenza virus emerged in Korea. During the outbreak, the virus caused the largest culling, especially in brown chicken lines. We determined the pathogenicity and transmissibility of the virus in 2 white chicken lines of the specific pathogen-free chickens, broilers and brown chicken line of Korean native chicken (KNC). A KNC had a longer virus shedding period and longer mean death time than others. Our study showed that this characteristic in the KNC might have contributed to a farm-to-farm transmission of the brown chicken farms.

Fatal cryptosporidiosis in a calf / 대한수의학회지

A calf suffering from diarrhea was admitted to the Animal and Plant Quarantine Agency for diagnostic evaluation. Postmortem examination revealed that the mesenteric lymph node was enlarged and small intestine wall was thin. Microscopically, a large number of small round organisms were attached to the small intestine villi. Villous atrophy and proprial neutrophil infiltration were also observed. Based on modified Ziehl-Neelsen staining, electron microscopy, and ELISA results, the calf was diagnosed with fatal cryptosporidiosis.

Loop-mediated isothermal amplification assay for the detection of Salmonella spp. in pig feces / 대한수의학회지

Salmonella are causative agents of gastroenteritis and systemic disease in animals. The invA gene was selected as a target sequence of loop-mediated isothermal amplification (LAMP) assay for diagnosis of Salmonella infection. The detection limits for broth dilution, spiked feces and enrichment were 10(4), 10(5) and 10(2) CFUs/mL, respectively. The LAMP assay developed in the present study may be a reliable method for detection of Salmonella spp. in pig feces.

Isolation of novel bovine parainfluenza virus type 5 (bPIV5) and its incidence in Korean cattle / 대한수의학회지

Four viruses showing cytopathic effects in MDBK cells were isolated from brains of cattle showing downer cattle syndrome in 2012. The isolates were confirmed to belong to the genus Rubulavirus of the subfamily Paramyxovirinae. Isolate QIA-B1201 had the ability to hemagglutinate red blood cells from several species of animals and was capable of adsorbing guinea pig erythrocytes on the surface of infected Vero cells. Nucleotide sequence analysis showed that two isolates (QIA-B1201 and QIA-B1204) had high similarity with other human and animal PIV5 isolates ranging from 98.1 to 99.8%. The highest sequence similarity of the two isolates corresponded to strain KNU-11 (99.8% at the nucleotide and amino acid level) isolated from suckling piglets in Korea in 2012. To evaluate the virulence of strain QIA-B1201, we inoculated bPIV5 into 5 week-old mice via both the intraperitoneal and intracranial route. Body weight was not significantly altered in mice inoculated with QIA-B1201. In this study, we isolated and characterized novel bPIV5s from brain samples showing downer cattle syndrome, but were not able to elucidate the pathogenicity of the bPIV5s in mice.

Abundance of biting midge species (Diptera: Ceratopogonidae, Culicoides spp.) on cattle farms in Korea

Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%).

Animal poisoning in Korea in 1974-June 2013 / 대한수의학회지

Animal poisoning has been occurred in Korea. However, the lack of the data about animal poisoning in Korea makes clinicians and diagnostician difficult to obtain information on poisoning cases. In this paper, we tried to gather information about animal poisoning from 1974 to June 2013 in Korea. Animal and Plant Quarantine Agency (QIA) record database were used to examine recent trends in animal poisoning. The analysis showed that the cattle was reported to be the most common species involved in animal poisoning and botulinum toxin constituted the primary group of toxicants. Animal poisoning occurred frequently on January and in Gyenggi-do. Although the data present in this manuscript is a little, it will be helpful to understand the general trend of animal poisoning in Korea.

Devastating endosulfan poisoning in Korean native cattle / 대한수의학회지

Here, we report the poisoning case of 10 cows. Several distinct clinical signs such as convulsion, excessive salivation, circling, lateral recumbency, and death were observed. Necropsy and histopathological examination did not reveal any significant abnormal findings. Moreover, no bacteria or viruses were detected in tissue, blood, and feeding food. However, endosulfan was detected from the stomach contents and microbials. Our results strongly suggest that death of cows may be closely associated with endosulfan poisoning.

Case report of Johne's disease in Korean black goat (Capra hircus aegagrus) / 대한수의학회지

Two Korean black goat (approx. 2 and 3 years old) showing diarrhea and chronic weight loss were submitted to Animal and Plant Quarantine Agency. At necropsy, there were thickening of small intestine and enlargement of mesenteric lymph nodes. Microscopically, they had granulomatous enteritis in the small and large intestine and granulomatous lymphadenitis. By polymerase chain reaction (PCR) and acid fast stain, strong positive reaction and acid-fast rod bacteria were detected. According to the result of histopathology and PCR, we confirmed this case as Johne's disease. As far as we know, this is the first report of Johne's disease in Korean black goat.

Antimicrobial resistance and frequency of BlaTEM in Escherichia coli isolated from non-diarrheic and diarrheic piglets / 대한수의학회지

Antimicrobial resistance is one of the most concerns in pig industry. Escherichia (E.) coli have been used for the indicator to monitor the antimicrobial resistance. In this study, 321 E. coli from diarrheic and non-diarrheic piglets were tested for antimicrobial resistance and frequency of Bla TEM. In non-diarrheic piglets, they were resistant to oxytetracycline (93%), streptomycin (92%) and sulfadiazine (90%) but susceptible to ceftiofur (99%), colistin (97%), and enrofloxacin (82%). The isolates from diarrheic piglets were resistant to enrofloxacin (72.9%), ceftiofur (17.6%), and colistin (11.3%), whereas the resistance was 1%, 18% and 3% in case of non-diarrheic piglets, respectively. The resistance for amoxicillin/clavulanic acid (54.1%) and ceftiofur (22%) was high in isolates from post-weaning piglets. The resistance for colistin was 15.2% in nursery piglets. Seventy-three percent of isolates from diarrheic piglets showed high multidrug resistance profile (more than 13 antimicrobials) compared to those from non-diarrheic pigs in which 71% of isolates showed moderate multidrug resistance profile (7 to 12 antimicrobials). The frequency of BlaTEM in E. coli from non-diarrheic and diarrheic piglets was 57% and 69%, respectively. The results might provide the basic knowledge to establish the strategies for treatment and reduce antibiotic resistance of E. coli in piglets.

Flow Cytometric Analysis of Lymphocyte Subpopulations of Cattle Infected with Bovine Leukemia Virus

We examined lymphocyte subpopulations of peripheral blood from BLV infected and noninfected Holstein-Friesian dairy cattle reared in Korea by flow cytometry using monoclonal antibodies specifically reactive with bovine leukocyte differentiation marker. Lymphocyte subpopulations expressing BoCD11b, B-B2, CD5, B, MHC II-DP, MHC II-DQ, and MHC II-DR antigens were significantly abundant in the BLV(+) group than the BLV(-) group (p<0.01). On double staining, subpopulation of B-1a(BoCD5+ BoCD11b+) lymphocytes was significantly increased in leukemic group. However, T-lymphocyte lineage expressing BoCD2, BoCD4, BoCD8, and WC1 antigens was significantly lower than in the BLV(+) group (p<0.01). However the absolute number of T-lymphocytes expressing BoCD2, BoCD4, BoCD8, and WC1 antigens in BLV(+) group remained with in the normal range. Furthermore mean ratio of BoCD4/BoCD8 in the BLV(+) groups was higher than that in the BLV(-) group. Taken together, cellular immune responses did not seem to significantly be decreased in the leukemic cattle.

Detection of Lawsonia intracellularis in diagnostic specimens by one-step PCR

Lawsonia intracellularis is not culturable with a standard bacteriologic culture. One step PCR assay as a clinical diagnostic method was developed for the rapid detection of porcine proliferative enteritis (PPE) caused by L. intracellularis. Primers were designed based on the p78 DNA clone of L. intracellularis. The one step PCR resulted in the formation of a specific 210-bp DNA product derived from L. intracellularis. The nonspecific amplification product was not detected with swine genomic DNA or other bacterial strains causing similar symptoms to L. intracellularis infection. The one step PCR was as sensitive as 100 pg of L. intracellularis genomic DNA. We applied this method to field specimens diagnosed as PPE by macroscopic observation. Of 17 mucosal scraping specimens, 16(94%) were identified as positive to PPE and 15(88%) of 17 feces specimens. These results suggest that the one step PCR can be used as a rapid diagnostic method for L. intracellularis infection.