This paper deals with the genetic properties of R plasmids in Salmonella originated from pigs and cattle. The plasmid DNA was examined for incompatibility, stability and fertility inhibition (F1), and gel electrophoresis was performed for isolation of plasmid DNA. Among the 66 conjugative R plasmids from 44 pigs and 22 cattle, 61 R plasmids (92.4 %) were Fi-, whereas the remainder were Fi+. The Inc groups of 66 R plasmids were determined with 7 standard plasmids. Twenty-six R plasmids were classified into Inc group Ialpha, H1, H2 or F1, 40 R plasmids being not classified with standard plasmids used, and the Inc group Ialpha (57.7 %) was most frequent. 3. Inc groups Ialpha H1, and F1 were identified in strains from swine, Inc groups H2 and F1 from cattle. The plasmid DNA profiles in 16 Salmonella isolated from pigs and cattle were confirmed as being 1 to 10 fragments by the gel eletrophoresis. Their molecular weight ranged 1.0 to 90 megadalton. The molecular weight of conjugative plasmids ranged 1.0 to 80 megadalton in 4 Salmonella (P-4, P-5, P-7 and P-8) isolated from pigs.

To determine whether an anti-Salmonella bacterium is involved in control of pathogen load in persistently infected cattle herds. 24 Holstein calves experimentally infected and 39 Holstein cows naturally infected with Salmonella spp. An Escherichia coli (designated as P8E5) that possessed anti-Salmonella activity was isolated from Salmonella-negative bovine feces obtained from a herd with endemic Salmonella infection. In vitro analysis involved enumerating Salmonella enterica serovar Typhimurium coincubated with E coli P8E5. In vivo analysis involved coadministration of Salmonella spp and E coli P8E5 or an E coli control strain to neonatal Holstein calves. Fecal samples were collected on multiple days after inoculation, and quantitative PCR assay was performed by use of Salmonella-specific primers. E coli P8E5 reduced viability of Salmonella spp in vitro. Shedding of Salmonella organisms was diminished in calves administered E coli P8E5, whereas the control strain of E coli had no effect on shedding of Salmonella organisms. In this study, an E coli strain was identified that possessed bacteriocin-like activity and was able to decrease viability of Salmonella organisms in vitro and in vivo. Therefore, it is possible that this organism could be representative of native microbiota that dampen Salmonella spp in persistently infected cattle herds.

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.

Objective—To determine whether selection for the homozygous A136R171 genotype that confers resistance to classic scrapie infection negatively affects production traits in sheep. Animals—996 commercial lambs obtained from 2 flocks at separate locations across 3 consecutive years. Procedures—Genotyping at codon 136 and 171 was performed by use of commercially available testing or a single-nucleotide polymorphism assay. Carcass data were collected without knowledge of genotype approximately 24 hours after slaughter by an experienced grader. The model to analyze associations between prion protein (PRNP) genotype and production traits was based on genotype, breed, or both as fixed effects and days on feed as a covariate. Results—Average daily gain was significantly associated with only combined codons 136 and 171. In flock 1, weaning average daily gain was significantly greater in AA136 sheep than heterozygotes; the difference between QR171 and RR171 sheep, compared with QQ171 sheep, were not significant although QR171 and RR171 sheep had higher values. However, in flock 2, average daily gain was significantly greater in AV136 sheep than AA136 sheep and in QR171 sheep than QQ171 sheep. Conclusions and Clinical Relevance—Findings suggest there is an advantage for average daily gain in lambs with an arginine allele at codon 171, but there were no other genotype effects on production traits. Thus, selection for the resistant arginine allele at codon 171 to comply with USDA scrapie eradication guidelines should not be detrimental to lamb production in commercial flocks. Effects of codon 136 on average daily gain were ambiguous.

Objective-To map canine mitochondrial proteins and identify qualitative and quantitative differences in heart mitochondrial protein expression between healthy dogs and dogs with naturally occurring and induced dilated cardiomyopathy (DCM). Sample Population-Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with induced DCM. Procedures-Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by greater than or equal to 2-fold between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. Results-Within narrow pH gradients of control canine heart mitochondrial samples, a total of 1,528 protein spots were revealed. Forty subunits of heart mitochondrial proteins that differ significantly from control tissues were altered in tissue specimens from dogs with naturally occurring and induced forms of DCM. The most affected heart mitochondrial proteins in both groups were those of oxidative phosphorylation (55%). Upregulation of manganese superoxide dismutase was suggestive of heart oxidative injury in tissue specimens from dogs with both forms of DCM. Evidence of apoptosis was associated with overexpression of the heart mitochondrial voltage-dependent anion channel-2 protein and endonuclease G in tissue specimens from dogs with induced DCM. Conclusions and Clinical Relevance-Alterations of heart mitochondrial proteins related to oxidative phosphorylation dysfunction were more prevalent in tissue specimens from dogs with induced or naturally occurring DCM, compared with those of control dogs.

Objective-To evaluate time-dependent alterations in gene expression of chemokines in bronchial epithelium of recurrent airway obstruction (RAO)-affected horses and whether alterations resulted from increases in gene expression of interleukin (IL)-17 in cells isolated from bronchoalveolar lavage fluid (BALF). Animals-8 RAO-susceptible horses and 9 control horses. Procedure-In 2 experiments, both groups of horses were evaluated after being maintained on pasture and after being stabled and fed dusty hay for 1, 14, 35, and 49 days (experiment 1) or 14 and 28 days (experiment 2). In experiment 1, gene expression of IL-8, chemokine (C-X-C motif) ligand 1 (CXCL1), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and Toll-like receptor 4 (TLR4) in epithelium and IL-8, IL-17, and TLR4 in BALF cells was measured. In experiment 2, bronchial biopsy specimens were evaluated for IL-8 immunoreactivity. Results-In RAO-susceptible horses after 14 days of challenge exposure, there was a 3- and 10-fold increase in gene expression of IL-8 for epithelial and BALF cells and an increase in IL-8 immunoreactivity in epithelial cells. Challenge exposure failed to alter gene expression of CXCL1, GM-CSF, G-CSF, and TLR4 in epithelial cells of any horses at any time point. During challenge exposure, gene expression of BALF cell IL-17 was downregulated in control horses (day 1) and upregulated in RAO-affected horses (day 35). Conclusions and Clinical Relevance-Epithelial-derived IL-8 may promote airway neutrophilia, but the inciting stimulus is unlikely to be IL-17 because upregulation of this gene is subsequent to that of IL-8 in epithelial cells.

Objective-To evaluate canine histiocytic sarcoma cell lines and tumor samples for dysregulation of the Kit/stem-cell factor (SCF), Flt3/Flt3 ligand (Flt3L), and Met/hepatocyte growth factor (HGF) receptor tyrosine kinase signaling pathways, as these are known to contribute to the differentiation and survival of normal dendritic cells as well as malignant transformation of dendritic cells in mouse models. Sample Population-4 histiocytic sarcoma tumor cell lines and 35 formalin-fixed histiocytic sarcoma specimens obtained from dogs. Procedure-Histiocytic sarcoma cell lines were evaluated for expression of Kit/SCF, Flt3/Flt3L, and Met/HGF by use of reverse transcriptase-PCR procedures. Histiocytic sarcoma cell lines and tumor samples were evaluated for mutations in Kit, Flt3, and Met by use of PCR analysis of genomic DNA, followed by both sequencing and fluorescent PAGE for deletions or internal tandem duplications. The ability of the multitargeted split-kinase inhibitor SU11654 to block proliferation and induce apoptosis of histiocytic sarcoma cell lines was also evaluated. Results-No mutations in Kit, Flt3, and Met were identified in any of the cell lines or tumor samples evaluated. Furthermore, SU11654 did not induce cellcycle arrest or apoptosis of histiocytic sarcoma lines, even at supratherapeutic doses. Conclusions and Clinical Relevance-These data suggest that dysregulation of Kit/SCF, Flt3/Flt3L, and Met/HGF signaling pathways is unlikely to occur in histiocytic sarcomas of dogs and that inhibitors of the Kit, Flt3, and Met pathways are unlikely to provide clinical benefit to dogs with histiocytic sarcomas.

Microsatellite allele analysis has been used for individual identification and paternity test. In the present study, the biological father of three puppies was determined by using microsatellite allele amplification analysis. The mother bitch of the litter was a poongsan dog. The three study dogs that could have inseminated the bitch, by being in the same residence, were a white Poosan dog, a mixed breed, and a white Jindo dog. DNA was obtained from all the relevant dogs by buccal swabbing. Four loci of tetranucleotide repeat microsatellite were PCR-amplified, and analyzed by polyacrylamicde gel electrophoresis and silver staining. The results of genotyping unambigously assigned the Poongsan dog as the biological father. There was no evidence of superfecundation. Therefore, the present study demonstrated the usefulness of microsatellite allele analysis as a simple, efficient method of paternity test in dogs.