Protein profiles of whole homogenates of anconeus (slow twitch) and biceps femoris (fast twitch) muscles of clinically normal dogs and of Labrador Retrievers with hereditary myopathy (HM) were resolved on flat bed polyacrylamide isoelectric-focusing gels. Three methods of sample solubilization were performed. The solubilization buffer, with high concentrations of urea, precipitated the zwitterionic detergent, but use of the buffer containing 3% NP-40, 9.2M urea, and 0.1M arginine resulted in better resolution and stability of pH gradient. Gels of anconeus muscle from clinically normal dogs contained 2 protein bands specific to anconeus muscle, whereas gels of biceps femoris muscle from clinically normal dogs contained 3 protein bands amplified in biceps femoris muscle that were barely detectable in anconeus muscle. The staining intensity of protein bands in biceps femoris muscles from Labrador Retrievers with HM was decreased, relative to controls. The quantitative analysis of peak height ratios of biceps femoris muscle revealed significant (P less than 0.05) differences between profiles of clinically normal dogs and Labrador Retrievers with HM.

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.

This paper dealt wih the distribution of Shigella spp. on 5 piggeries in Taegu and Kyongbuk during the period from August to October 1987. Isolated Shigella were examined for serogrouping, antimicrobial drug resistance and detection of R plasmid. Genetic properties of R plasmid in Shigella were examined for fertility inhibition (F1) and gel electrophoresis was performed for the isolation of plasmid DNA. Of total 2,978 samples from 5 piggeries, 82 strains (2.8 %) of Shigella spp. were isolated from 82 samples. The isolated strains were identified as S. dysenteriae (60 strains), S. flexneri (20 strains) and S. sonnei (2 strains). Of the 82 strains examined 67 (95.1 %) were resistant to one or more antibiotics, such as ampicillin (Am), chloramphenicol (Cm), kanamycin (Km), nalidixic acid (Na), rifampicin (Rf), streptomycin (Sm), sulfademethoxine (Su), and tetracycline (Tc) and higher resistance to Su (90.2 %), Sm (63.4 %) and Tc (63.4 %). Of the 78 resistant Shigella strains 26 (33.3 %) harbored conjugative R plasmids and the transfer frequency of Sm (50.0 %), Cm (33.3 %) resistance was much higher than that of the other drug resistance. The most common resistant patterns were SmSuTc, Su and AmSmSuTc. Out of the 26 Shigella R plasmids examined for Fi, 14 (53.8 % were Fi + and the remainder were Fi-. The plasmid DNA profiles in Shigella spp. (9 strains) isolated from pigs were confirmed as being 2 to 9 fragments by the gel electrophoresis. Their molecular size ranged 2.17 to 87.62 kilobase (Kb). All strains of Shigella spp. consisted in 15.4 Kb plasmids.