The In vitro drug susceptibility of 83 strains of Bordetella bronchiseptica recoverd from Korean pigs with atrophic rhinitis was investigated by the use of disk diffusion method. The majority of the organisms were highly resistant in order of prevalence to penicillin (98.7%), ampicillin(91.5%), streptomycin (90.3%), triple sulfa (83.1%), and trimethoprim/sulfamet-hoxazole (70.7%) while none of them were resistant to gentamicin, only 3.6% to colistin, chloramphenicol and kanamycin and 6.0% to tetracycline. The percentage of the organism resistant to bicozamycin, cephalothin and neomycin were 34.9%, 34.1% and 18.4%, respectively. A high prevalence of multiple drug resistance was observed and the 3 most common resistant patterns among 35 patterns noted were Am Pc Sm Sss Sxt(26.5%), Am Cf Pc Sm Sss Sxt(12%) and Am Bm Pc Sm Sss Sxt(9.6%) patterns

In order to know the effect of dexamethasone on the induction of the rabbit viral hepatitis, the pathological changes were observed in the native rabbits, 2 to 6 months old in age, that were injected by dexamethasone and liver emulsion of Angora rabbit naturally infected with viral hepatitis. The native rabbits injected by dexamethasone and liver emulsion were infected with viral hepatitis and died between 2 and 7 days after inoculation. Clinical signs and gross lesions were very similar to those of Angora rabbit which had naturally occurred. In microscopical findings, the hepatic lesions were characterized by peripheral necrosis of the lobules, and peripheral necrosis of the lobules with fatty changes of hepatic cells occurred in a few cases. Perivascular lymphocytic infiltration in the central nervous system was observed in some cases. The lesions of the other organs were very similar to those of Angora rabbit. On the other hand, the native rabbits that were injected by only liver emulsion of Angora rabbit naturally infected with viral hepatitis were not infected with the disease except in very few cases

Appreciable radiation exposures certainly occur in the workers who handle radioiodine in biochemical research, nuclear medicine diagnostics with the development of nuclear industries. But in the case of nuclear accidents, the early medical treatment of radiation injury should be necessary but little was reported in Korea till now. Accordingly, to achieve basic data for protective roles and medical treatment of radiation injury, the present studies were carried out to evaluate the decontamination of radioiodine by the administration of the antithyroid drugs. The administration of sodium iodide and potassium iodide results in rapid excretion of radioiodine and reduction of the whole body retention than the saline-only group. Regarding thyroid protective effects, sodium iodide, potassium iodide results in rapid excretion of radioiodine and reduction of the whole body retention than the saline-only group. Regarding thyroid protective effects, sodium iodide, potassium iodide and saline were effected significant in order. In the control(saline) group, if administered with enough fluids, the whole body retention of radioiodine is reduced temporary shifts. But as far as radioprotective effects are concerned, saline was not more protective than the other groups. In conclusion, in case of nuclear accidents, if being administered sodium iodide and saline as quickly as possible, the radioprotective effects against the radiation hazard might be markedly increased in the internal contamination of radioiodine

The prevalence of yeasts in mammary glands of dairy cows and teat cups of milking machines was studied in Chinju area. The rate of subclinical yeast infection in 330 quarters was 3.6 %. Of 12 isolates from the milk, 4 Candida pseudotropicalis, 3 C. tropicalis, 2 C. krusei, 2 C. albicans and 1 Rhodotorula spp were identified. The 91.7 % of the isolates belonged to the genus Candida and C. pseudotropicalis was the predominant species. From 20.5 % of 200 teat cups tested, 51 strains of yeasts were isolated. These were 13 C. pseudotropicalis, 9 C. guilliermondii, 7 C. tropicalis, 5 C. krusei, 5 C. parapsilosis, 3 C. albicans, 2 Torulopsis glabrata, 2 Geotrichum candidum and 5 unidentified yeasts. C. pseudotropicalis was most frequently encountered

This study was conducted to isolate etiological agents from the 103 scouring piglets in Kyongnam area and also carried out antimicrobial drug susceptibility test and epidemiogical survey. The incidence of scouring piglet was most prevalent in 81.6% at the age of 2 to 4 weeks after birth, while the rate was less than 10% at the age of 5 to 6 weeks and under 1 week after birth. When comparing the isolation frequency of each etiological agent, enteropathogenic E. coli was most prevalent in 46.6%, thermophilic Campylobacter in 26.2% and Salmonellae was in 8.7% in that order. In the OK serotyping for 117 isolates of enteropathogenic E. coli, type 0141 : K85(20.5%), 0157:K88ac(14.5%), 0138:K81 and 0149:K91 (13.3%) were encountered most frequently. In the biotyping for 27 isolates of thermophilic Campylobacter, most strains of C. jejuni belonged to type I (50.0%) and II (25.0%), and most strains of C. coli belonged to biotype I (78.9%). In the serotyping for 9 strains of Salmonellae, 3 strains were grouped as D, 2 strains as C and 1 strain each was group B and E. The other 2 strains were untypable. The 117 isolates of enteropathogenic E. coli were resistant more than 90% to erythromycin, penicillin, tetracycline and streptomycin, whereas about 90% of the isolates were sensitive to kanamycin and gentamicin. In the case of Salmonellae, all of the isolates were resistant to penicillin, but about 89% of the isolates were sensitive to gentamicin and colistin. All of C. jejuni and C. coli isolates were resistant to cephalothin, but more than 89% of C. jejuni and C. coli were sensitive to kanamycin and gentamicin

Light-microscope studies of the coccidial organisms found in the Bursa fabricii from chickens showing some specific signs were carried out, and the etiological agent was estimated as the parasite belonging to the Family Cryptosporiidae. The specific gross pathological signs were intestinal hemorrhage and atrophy of the Bursa fabricii and hyperplasia was associated with the presence of organisms attached to the epithelial cells lining the plicae of the bursa of Fabricius in the microscopical findings

To establish a laboratory animal model for study on development of diagnostic methods for infectious bovine rhinotracheitis virus(IBRV), experimental infection of the virus to rabbits immunosuppressed with dexamethasone(DX) were carried out. When lymphocyte activity was measured by lymphocyte transformation to phytohaemagglutinin parallel with total and differential leucocyte counting, both groups treated with 2.0mg DX once and 1.0mg DX daily showed marked immunosuppression between 5 to 72 hrs. after administration. The degree of suppression of lymphocyte activities was more remarkable in the latter group. IBRV PQ7 strain at 10** (7.5) TCID50/0.2ml was inoculated into conjunctival sacs of rabbits immunosuppressed with DX and non-treated. During 3 weeks observation, the immunosuppressed groups revealed mild conjunctivitis, viremia and virus recovery by 33.3 to 100%, whereas the DX nontreated group showed viremia and virus recovery with no clinical conjunctivitis in one of three rabbits(33.3%). In conclusion, it was indicated that experimental infection of IBRV PQ7 strain to rabbit was limited in prerequisite to immunologic modification by administration of immunosuppressive drugs

The present study was carried out to investigate C. jejuni and C. coli in chicken. Also were examined the pathogenicity of the isolates in chicks by experimental inoculation. Thermophilic Campylobacter were isolated from 34 (45.9%) of the 74 specimens, and classified as 21.6 % C. jejuni, and 24.3 % C. coli. In the biotyping of 16 strains of C. jejuni isolates, 37.5 % of the strains were grouped as biotype I, 62.5 % as biotype II. In the case of 18 strains of C. coli isolates, 49.9 % of isolates were grouped as biotype I, 55.6 % as biotype II. In oral inoculation with 10** (4)cfu of Capmylobacter isolates into infant chicks (1 to 3 days-old), 17 days-old and 34 days-old chicks, 32.5 % of the chicks developed diarrhea on day 1, 52.5 % on day 3, 70.0 % on day 5, and 27.5% on day 7, and the peak incidence of diarrhea was reached on day 5. The organisms were found to be discharged in feces one day afterwards. C. jejuni and C. coli strains were detected from the feces in 87.5 % of the chicks on day 5.

Attempts of these studies were made to investigate the nonspecific congenital focal accumulation of etcodermal glial cells in the brain of normal piglets. The brain samples were taken from 1-, 10-, 20-, 35-, 45- and 70-day-old piglets from a SPF-pig farm and three model pig farms. Occurrences of neuroglial cell foci(NCF) on the brain were observed with light microscope. Appearance degrees of the congenital NCF on 10 to 16 cross section slides per a piglets brain were tentatively designed on a scale from deg. + to +++ by NCF number: +, less than 20 of NCF number; , 21-40 of NCF number: +++ , more than 41 of NCF number. NCF in the brain were obseved mainly on the cerebrum. Regions of higher frequencies on the cerebrum were ordered as subependymal layers of the lateral ventricles, peripheral regions of lateral ventricles in the white matter and some neuron layers under the molecular layer of the gray matter. But NCF were not observed in the cerebellum, pons, medulla oblongata and spinal cords. On the subependymal layers of the lateral ventricles, NCF were observed in 100% of 27 piglets, and appearance degree of was observed in 10 piglets (37.0%), ++ in 10 piglets (37.0%) and + in 7 piglets (26.0%) of 27 piglets, respectively. On the white matter of the cerebrum, NCF were observed in 25 piglets (92.6%) of 27 piglets, and appearance degree of +++ was observed in 3 piglets (11.1%), in 13 piglets(48.2%), + in 9 piglets (33.3%) and- in 2 piglets (7.4%) of 27 piglets, respectively. On the gray matter of the cerebum, NCF were observed in 21 piglets (77.8%) of 27 piglets, and appearance degree of +++ was not observed, appearance degree of ++ was obseved in 6 piglets (22.2 %), + in 15 piglets (55.6%) and - in 6 piglets (22.2%) of 27 piglets, respectively. NCF tended to be converged appearance on some regions and tended to be decreased markedly from 35th day after birth, and the shapes of NCF were global or oval forms crowded by analogous shaped and stained cells in the empty spaces of the brain substrate or on one side of the blood vessels

The phenotypes of hemoglobin, albumin and transferrin of 302 Jindo dogs in Jindo area were studied by starch gel electrophoresis for hemoglobin and albumin, and by polyacrylamide gradient gel electrophoresis for transferrin. In the hemoglobin phenotypes, three phenotypes, HbAA, HbAB and HbBB, which were controlled by two allelic genes, Hb** (A) and Hb** (B), were observed and their frequencies of appearance were 1.65%, 10.60% and 87.75% respectively. The distribution of gene frequency was calculated as 0.0695 in Hb** (A) and 0.9305 in Hb** (B). In the albumin phenotypes, three phenotypes, Alb FF, Alb FS and Alb SS, which were controlled by two allelic genes, Alb** (F) and Alb** (S) were observed and their frequencies of appearance were 12.59%, 25.56% and 61.85% respectively. The distribution of gene frequency was calculated as 0.2537 in Alb** (F) and 0.7463 in Alb** (S). Analysis of transferrin phenotypes showed 6 different types which were controlled by three allelic genes, Tf** (B), Tf** (C) and Tf** (D), and their frequencies of appearance were 54.04% in TfBB, 17.54% in TfBC, 9.82% in TfBD, 8.07% in TfCC, 7.37% in TfCD and 3.16% in TfDD. The distribution of gene frequency was calculated as 0.6772 in Tf** (B), 0.2053 in Tf** (C) and 0.1175 in Tf** (D)