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1.
Eschericia coli bacteriophages were isolated from the intestines of chickens. These phages had different lytic patterns, and were propagated in nutrient broth containing 0.4 gm calcium chloride/litre. The agar layer technique was used to determine the routine test dilution (RTD) and plaque morphology. The phages differed in their 1) morphology, 2) RTD values, and their ability to lyse E. coli strains from various animals. All phages isolated lysed human K12 E. coli strains, whereas only two phages lysed the chicken E. coli strain. Phages isolated lysed E. coli from chicken, bovine, ovine, equine, and human, but not from porcine, canine and other avian species. 相似文献
2.
The pathogenicity of V. coli for conventional swine was studied by inoculating pigs with cultures of V. coli and V. coli infected gut of gnotobiotic pigs. Thus, six conventional pigs were inoculated with strains of V. coli freshly isolated from infected gnotobiotic pigs. The cultures were grown in simulated sows milk, and added to the feed. Two other groups, of three pigs each, were infected by administration of minced intestine from two gnotobiotic pigs, heavily infected with the organism. Vibrio was isolated from all pigs, including five of the six controls, but larger numbers were isolated from the inoculated groups, especially from those fed macerated gut. Clinical signs of disease were not observed. 相似文献
3.
Strains of enterobacteria (nine Escherichia coli and two Salmonella) isolated from primary or secondary infections in the dog, cat, pig, calf and kangaroo were studied for the presence of extrachromosomal drug resistance factors (R factors). Seven strains of E. coli and two strains of Salmonella transferred resistance involving the following antibiotics: streptomycin, ampicillin, chloramphenicol, neomycin and tetracycline. All strains harboring R factors transferred streptomycin resistance and the identified resistance patterns were as follows: Sm Am, Sm Te, Sm Neo, Sm Am Te, Sm CI Neo and Sm Am CI Te. The levels of resistance observed were comparable for all donor strains and their converted recipients. Strains of E. coli harboring R factors were isolated from three dogs that had died of either otitis (followed by a generalized infection), enteritis or bronchopneumonia — secondary to distemper. The bacteria isolated from cats were recovered at the necropsy of animals that had died of purulent pleuresy and feline panleukopenia. The other strains (two Salmonella and one E. coli were isolated from fatal enteric diseases in the pig, calf and kangaroo. 相似文献
4.
Studies on the site of proliferation of Pasteurella haemolytica in the bovine nasal cavity have been carried out. P.haemolytica were isolated from 15 selected major anatomical areas of the nasal cavity in calves with high numbers of P.haemolytica following shipment from Western Canada. When the organisms were present in the nasal cavity of live animals in low numbers, they were isolated from many, but not all, areas. P.haemolytica was isolated post mortem from one or more selected areas of several nasal cavities in spite of negative antemortem cultures. By the direct fluorescent antibody technique, P.haemolytica was demonstrated at the surface of nasal epithelial cells. Organisms were not seen in or between epithelial cells nor in the ducts nor alveoli of glands. The findings were similar when high and low numbers of P.haemolytica were present in the nasal cavity. 相似文献
5.
Nineteen strains of Pasteurella spp., but no viruses cytopathogenic for bovine embryonic kidney cells were isolated from pneumonic lesions present in “normal” veal calves at slaughter. In studies on two herds of native cattle and six lots of western feeder calves, Pasteurella spp. were isolated from nasal swabs from healthy cattle and those with shipping fever. Viruses of the psittacosis-lymphogranuloma group were isolated from nasal swabs from animals in five groups. Viruses provisionally identified as bovine enteroviruses were isolated from nasal swabs of calves in two lots. There was serologic evidence of a temporal association of myxovirus para-influenza 3 (PI3) with shipping fever in three lots of calves. From two of these three lots, strains of PI3 were isolated from ten animals, four of which had clinical shipping fever at the time of virus isolation. 相似文献
6.
Three hundred and seventy strains of fecal Escherichia coli were isolated from pigs in one barn and 475, 539 and 490 strains were isolated at each of three successive samplings in another barn. The majority of the E. coli isolates obtained at any one sampling belonged to a small number of E. coli types. Three repeated samplings in one barn indicated that the dominant E. coli types harboured by pigs in this barn were constantly changing. The results also suggested that, within a particular barn, a successive batch of pigs could experience the same sequence of E. coli types. Colicin production appeared to be associated with dominant strains and the proportion of colicin producers in different investigations ranged from 36 to 68%. 相似文献
7.
The intracheal inoculation of pigs with Haemophilus suis led to the production of Glasser's disease at every attempt without significant pulmonary involvement. Isolation of this organism from the experimental animals was possible only in the acute phase of the disease. The indirect fluorescent antibody technique when applied to frozen sections of tissues obtained from the experimentally infected pigs at autopsy, revealed a few rod forms but mostly “round bodies” of H. suis in animals from which the organism was isolated, and “round bodies” only in the pigs from which the organism was not isolated. Attention is drawn to the similarities between the lesions caused by H. suis and Mycoplasma hyorhinis, and to the confusion which may result therefrom. It is stressed that the laboratory diagnosis of these two diseases is complicated by the fact that both agents may not be isolated on the media commonly used in diagnostic laboratories. Both organisms necessitate the use of special media where the clinical and autopsy results indicate polyserositis and arthritis. 相似文献
8.
Approximately 26% of rendered and 10% of ready-to-eat products contained species of the genus Clostridium.Eleven species of clostridia were isolated from a total of 524 products tested. Some products harboured more than one species. C. sporogenes, one of the most heat resistant organisms, was the most common type isolated. C. sordellii produced a transient illness in guinea pigs while all other species were innocuous. 相似文献
9.
Bacteriological examination of faeces and swabs from fourteen species of reptiles predominantly constrictors, yielded six serotypes of Salmonella as well as Arizona hinshawii, Proteus species, Citrobacter freundii and Enterobacter species. Organisms isolated were identified using conventional bacteriological methods and yielded two serotypes of salmonellae not previously identified in Canada: Salmonella nima and Salmonella 58:a. 相似文献
10.
Antimicrobial agents were added to the feed of swine for three weeks to determine the interrelationships of potentially pathogenic agents in the nasal tract, turbinate atrophy and weight gains. Bordetella bronchiseptica was not isolated from the groups fed the combination of chlortetracycline, penicillin and sulfamethazine. B. bronchiseptica was found in some pigs after the feeding trail, but this organism was not significantly associated with turbinate atrophy at the time of slaughter. Mycoplasma hyorhinis was not found in the nasal passages of the pigs that received feed containing high concentration chlortetracycline but was found in pigs that received other diets. Hemophilus suis was not significantly reduced by any of the treatments used. The organisms studied in the pigs were not isolated from the personnel handling the pigs. 相似文献
11.
Four Salmonella strains were used. With two, S. canada and S. enteritidis, establishment of infection in pigs was poor. Although improved establishment was achieved with two strains of S. typhimurium, no infections were extensive. No significant difference was detected between excretion of infecting strains by pigs receiving chlortetracycline at levels of ten gm per ton of feed and that by control counterparts. Comparable establishment of S. typhimurium S192 was achieved in pigs receiving 20 or 40 gm of chlortetracycline per ton. Resistant variants were isolated from some animals in all experiments using S. typhimurium S192. Almost without exception such variants were isolated only after specimen enrichment. The numbers of specimens from test animals yielding resistant variants were more than twice those of control counterparts. Numbers of such variants in material from the former were much greater. In vitro transfer of resistance to S. typhimurium S192 was demonstrated both in waters from drinking troughs and during specimen enrichment. The former, indicating the risk of transfer in pigs' environments and packing houses, has disturbing implications for public health. The latter emphasizes the difficulties of determining antibiotic sensitivity of pathogens as they occur in the animal body. 相似文献
12.
Four stumptail Macaque monkeys (Macaca arctoides) were each inoculated with approximately 10 10 organisms from a culture of Brucella canis. Two animals were inoculated via the oral and conjunctival route and the other two monkeys were inoculated intravenously with the organisms. A fifth animal served as a control. Blood samples were taken at weekly intervals for hematological, serological and bacterialogical studies. The monkeys were killed at five and ten weeks post-inoculation and tissues taken from a variety of organs for bacterial culture. B. canis was isolated from the peripheral blood of inoculated monkeys for up to seven weeks post inoculation and all infected monkeys developed significant neutralizing antibody titers to the organism. The bacterium was isolated from some tissues, including the uterus of one monkey, in the two animals killed at five weeks post-inoculation. Focal granulomatous lesions were sometimes observed in the liver, spleen and lymphoid tissue of inoculated monkeys. Such lesions are similar to those described in other brucella infections. Human infections with B. canis have occurred and the possible dangers entailed in exposure to the organism should again be emphasized. 相似文献
13.
This study was initiated to determine the etiologic and pathogenic significance of an American strain of bovine viral diarrhea (BVD) virus (strain NADL-MD) in enteritis of neonatal calves (calf scours). Three colostrum-fed calves from dams exposed intravenously to BVD virus at 6, 16 and 25 days prepartum, respectively, had moderate diarrhea persisting until the eighth day of life. The BVD virus was isolated from all 3 calves and persisted up to 93 days in 1 calf, indicating either that BVD was transmitted in utero or via the dam's milk. Three specific pathogen free (SPF) calves permitted dams' colostrum for the first 4 feedings and then given milk replacer were exposed orally on the day of birth to BVD virus. One calf died of neonatal enteritis 28 hours post-exposure and at necropsy the BVD virus was isolated from several of its organs. The remaining 2 calves had a mild diarrhea persisting to the eighth day of age. Two calves permitted dams' colostrum ad lib. for 72 hours, and then weaned, were exposed orally to BVD virus. Both calves had a mild persistent diarrhea and BVD virus was isolated from their blood for 56 days post-exposure. Of 13 SPF, colostrum-deprived calves exposed orally or intranasally at birth to the BVD virus, 4 had severe diarrhea and died of neonatal enteritis from 38 hours to 13 days postexposure. Isolations of BVD virus were made from several of the organs of the calves at necropsy. All of the 9 surviving calves had a moderate to severe diarrhea frequently persisting for 7 to 10 days, and BVD virus was isolated from the survivors up to 103 days postexposure. Several strains of Escherichia coli were isolated from calves after the second day of life, but were neither pathogenic for mice, nor serologically related to strains of E. coli usually associated with outbreaks of calf scours. Four colostrum-deprived SPF calves were exposed orally at birth to a strain of E. coli isolated from the intestine of the calf with the most acute symptoms and fatal neonatal enteritis. None of the four calves receiving the E. coli had diarrhea. One calf, however, had respiratory distress and died on day 5. Two SPF colostrum-deprived control calves had neither diarrhea nor respiratory distress. The above findings support the conclusion that BVD virus should not be overlooked as a primary cause of the neonatal calf enteritis complex. 相似文献
14.
A mycoplasma was recovered from the untreated conjunctival membranes of nine sheep affected by Pink-eye. It was neither isolated from the conjunctiva of treated animals which were affected nor from the conjunctiva of normal animals either in contact or not in contact with affected animals. Bacteria found on normal conjunctival membranes were Neisseria ovis, Escherichia coli, Staphylococcus epidermididis, Streptococcus and Bacillus spp. Bacteria found in clinical cases of Pink-eye were N. ovis, E. coli, a Streptococcus and Pseudomonas spp. 相似文献
15.
The in vitro susceptibility of 103 cultures of E. coli isolated from scouring and nonscouring pigs, and four cultures of Salmonella isolated from a case of necrotic enteritis was tested against Ampicillin contained in nutrient broth at concentrations of 0, 0.1, 1.0 and 5.0 uG per ml. of the medium. All but three cultures of E. coli were found to be susceptible to 5.0 uG/ml., all Salmonella isolates were also susceptible to this concentration of the antibiotic. Susceptibility of E. coli was also tested by plating dilutions of fecal samples obtained from either a scouring or a nonscouring pig, with E.M.B. agar containing 0, 0.1, 1.0, 2.5, 5.0 and 10.0 uG Ampicillin per ml. of the medium. No difference in the growth of E. coli was observed at 0, 0.1 and 1.0 uG concentrations. The three higher concentrations of the antibiotic inhibited the growth of E. coli proportional to the amount of Ampicillin in each concentration.Ampicillin proved very effective in alleviating the symptoms of hemorrhagic enteritis in a 11-week old pig. The disappearance of scours was associated with the replacement of the previously existing sero-biotypes of fecal E. coliwith another aberrant type of E.coli which produced H2S. No Ampicillin resistant strains of E. coli emerged following treatment of the animal with this antibiotic. 相似文献
16.
A study of the prevalence of yeast-like fungi in the mammary glands of dairy cattle was conducted in Minnesota. Quarter samples from 6,020 cows were cultured for yeast. Growth of organisms was obtained from 3.2% of the quarter milk samples. The rate of yeast infection for Minnesota dairy cattle in this study was 2.0%. The majority of the yeast isolated belonged to one of four species of the Candida genus. Candida krusei, Candida parakrusei, Candida guilliermundi, and Candida tropicalis, comprised 89% of the yeasts isolated. All of these species have been reported to cause clinical mastitis (1, 7, 9, 10, 12, 13, 15, 16). It would appear that yeast-like fungi are of sufficient prevalence in mammary glands that yeast infection would be considered in the differential diagnosis in cases of clinical mastitis. 相似文献
17.
A number of different Salmonella types were found in the mesenteric lymph nodes of stray dogs although none were isolated from the feces of these same animals. 相似文献
18.
Fifteen gnotobiotic pigs varying in age from three to eight weeks were exposed to 23 strains of V. coli isolated from swine with clinical and/or pathological signs of swine dysentery and also from clinically healthy pigs. Clinical or pathological signs of swine dysentery were not produced, although the organism was readly established in the sedimentary tract. Culture of feces, alimentary tract and environment revealed V. coli in large numbers, but no bacterial growth was obtained from other organs. The histopathology and serology are discussed. 相似文献
19.
An outbreak of fibrinous pleuropneumonia was observed in October 1971 in Saskatchewan on a farm of 900 feeder pigs. Morbidity and mortality were low. Pathologic-anatomic findings included fibrinous pleuritis, pulmonary vascular thrombosis and necrotizing fibrinous pneumonia. Hemophilus parahemolyticus was isolated from the lungs of affected animals. In addition pulmonary lesions were found which suggested an adenovirus infection. It was speculated that the viral infection possibly predisposed the pigs to the Hemophilus infection. The H. parahemolyticus isolate was sensitive to common antibiotics. 相似文献
20.
Contents of the rumen, abomasum, ileum, and colon of 100 fattened cattle were examined for the presence of Cl. Perfringens. Liquid medium iniculated with each sample of gut content was tested for the presence of toxins of Cl. Perfringens. Identification of Cl. Perfringens was based on atmospheric requirements for growth, colonial morphology, and stormy fermentation in litmus milk. Identification of toxins was based on neutralization tests in guinea pigs and mice. Cl. Perfringens was isolated from 202 of 399 samples. In 105 additional cultures, colonies characteristic of Cl. Perfringens were present but could not be isolated in pure culture. Cl. Perfringens type D toxin was identified in only one culture, which was inoculated with ileum contents. Type A toxin was identified in eight of the 24 samples from the one lot of samples in which no type A antitoxin was used. There were no identifications of toxigenic types B, C, or E. The results indicate that an isolation from necropsy specimens of untyped Cl. Perfringens or type A Cl. Perfringens is in itself of little significance. The infrequency of occurrence of the other toxigenic types in this survey of healthy cattle indicates that recovery of these types from necropsy specimens may be of more significance in determining the cause of death. 相似文献
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