Biomedical subjects

C M Scanlan

Publications and source records attributed to C M Scanlan.

46 records · Page 3Linked to original sources

PubMed1983

Culture of uterine flushings, cervical mucus, and udder secretions collected post-abortion from heifers artificially exposed to Brucella abortus.

Uterine flushings, cervical mucus swabs and udder secretions collected at weekly intervals from five mixed breed beef cows (four Brucella abortus strain 19 vaccinates, and 1 non-vaccinate) were cultured for Brucella abortus . Prior to sampling, four of the five had aborted 7-to 8-month-old fetuses and one gave brith to a weak calf. The fetuses and/or udder secretions from the cows were culture positive for B. abortus at the time of parturition. Three of the cows developed persistent udder infections. Two of these cows were also shown to have brucellae in their cervical mucus for 10 and 20 days and in their uterine flushings for 17 and 41 days after parturition, respectively. One other cow had brucellae in the cervical mucus for 16 days and in the uterine flushings for up to 36 days post-abortion. All attempts to isolate the organism from this cow's udder secretions in culture were negative. In two cows with culture-positive uterine flushings, isolations of brucellae were made subsequent to normal postpabortion return to estrus.

Journal Article↗

PubMed1983

Bovine rumenitis - liver abscess complex: a bacteriological review.

Fusobacterium necrophorum is considered to be a member of the normal rumen flora and is the primary etiologic agent of bovine liver abscesses. Of the three biotypes of F. necrophorum, A, B, and C, only biotypes A and B have been implicated in the disease. Type B is the predominant biotype isolated from ruminal lesions and type A is the predominate biotype isolated from liver abscesses. Type A is usually found in pure culture in the liver abscesses; whereas, type B is usually found in mixed culture with either type A or with other bacterial species. Corynebacterium pyogenes, Streptococcus spp., Staphylococcus spp., and Bacteroides spp. are the most prevalent bacteria recovered from mixed cultures. Corynebacterium pyogenes is the most common species isolated and can cause disease synergistically with type B isolates.

Animals↗

PubMed1983

Comparative biological features of a rat liver abscess model induced with three Fusobacterium necrophorum strains.

Several biological features were compared in a rat liver abscess model, using intraportal inoculations with 3 bovine strains of Fusobacterium necrophorum which varied in virulence. Serum alanine aminotransferase activities were increased significantly (P less than 0.05) in rats inoculated with F necrophorum 2101 by postinoculation hours 6, 12, and 24. Thereafter, alanine aminotransferase values returned to base line for the remainder of the experiment. Also, rats inoculated with F necrophorum 2101 had a significantly greater (P less than 0.05) weight loss than did the control rats during the first 5 postinoculation days and developed leukocytosis characterized by a neutrophilia with a left shift. The duration of the bacteremia was related directly to the virulence of the F necrophorum strain. Fusobacterium necrophorum 2101, a biotype A which was the most virulent, induced the most persistent bacteremia; F necrophorum 2035, a biotype B which was the least virulent, produced the shortest bacteremia; and F necrophorum 2030, a biotype AB which was of intermediate virulence, led to bacteremia of intermediate duration. Plasma endotoxin was demonstrated intermittently during the first 24 hours, but did not correlate with the bacteremia.

Alanine Transaminase↗

PubMed1983

Experimental hepatic necrobacillosis infection in cattle.

Viable cultures of Fusobacterium necrophorum were inoculated into the hepatic portal veins of 7 cattle. The experimentally produced hepatic necrobacillosis lesions were described from 30 minutes through 36 hours. The lesions were established by 2 different host-bacterial interactions. Most frequent, microabscesses were initiated by diffusely distributed bacteria and were observed from 30 minutes through 2 hours. Gross abscesses from 3 through 8 hours had centrally located abscess cores and were encircled by leukocytes which were predominantly neutrophils. Lesions from 12 through 36 hours had abscess cores that were encircled by leukocytes which were predominantly macrophages. Less frequent, emboli of F. necrophorum initiated infections in hepatic sinusoids or telangiectatic lesions. Hepatocytes adjacent to the bacteria exhibited coagulation necrosis and few leukocytes were observed in these lesions.

Animals↗

PubMed1982

Comparative in vitro leukotoxin production of three bovine strains of Fusobacterium necrophorum.

The in vitro leukotoxic activity of 3 bovine isolates of Fusobacterium necrophorum which varied in pathogenicity were compared. Monolayers of mouse peritoneal macrophages were exposed to culture filtrates from each F necrophorum strain, and cell viability was determined, using the trypan blue dye exclusion test. Two methods were used for production of the leukotoxin: (1) medium M-1 continuous dialysis sac cultures and (2) brain-heart infusion agar plate cultures. Supernatant cultural fluids containing the leukotoxin were subjected to membrane-partition chromatography, using ultrafilters with approximate molecular weight (mol wt) exclusion limits of 100,000, 10,000, 2,000, and 500. All ultrafiltrates had a cytotoxic effect on the monolayers. Cytotoxic activity was not found in the ultrafilter residues or in the control media ultrafiltrates. Comparative study of leukotoxin production indicated that F necrophorum 2101, type A, produced the most leukotoxin; F necrophorum 2030, type AB, produced slightly less leukotoxin; and F necrophorum 2035, type B, produced small amounts of leukotoxin. Endotoxin activity, as demonstrated by the mouse lethality test, was found in the residues of the XM-100A ultrafilter (100,000 mol wt), but not in the filtrates. Culture supernatant fluids and the XM-100A ultrafiltrates were positive for endotoxin, using the limulus amebocyte lysate assay; however, the other ultrafiltrates with lower mol wt exclusion limits were negative.

Animals↗

PubMed1982

Studies of Fusobacterium necrophorum from bovine hepatic abscesses: biotypes, quantitation, virulence, and antibiotic susceptibility.

Isolates of Fusobacterium necrophorum were obtained from 124 bovine hepatic abscesses (in 119 cattle) and from the ruminal contents of 12 cattle. Three biotypes (A, AB, and B) were found. Type A isolates were most common in hepatic abscesses, and type B isolates were most common in ruminal contents. Virulence studies in mice indicated that type A isolates were more pathogenic than types AB or B isolates. The difference in virulences between types A and B isolates was not related to the toxicity of the endotoxin. Results of serotesting (passive hemagglutination) showed that a wide heterogeneity existed between isolates. Minimal inhibitory concentrations of antibiotics for 12 of the isolates (7 type A, 1 type AB, and 4 type B) were as follows: less than or equal to 0.06 IU of penicillin G/ml; less than or equal to 0.5 micrograms of cephaloridine/ml; less than or equal to 2 micrograms of chloramphenicol/ml; less than or equal to 0.06 micrograms of clindamycin/ml; less than or equal to 8 micrograms of erythromycin/ml; less than or equal to 128 micrograms of gentamicin/ml; less than or equal to 0.25 micrograms of oxytetracycline/ml; and less than or equal to 4 micrograms of tylosin/ml.

Animals↗

PubMed1979

Occurrence of anaerobic bacteria in diseases of the dog and cat.

A survey for anaerobic bacteria was conducted in 314 clinical specimens from dogs and cats. A total of 187 anaerobic isolates in pure and mixed culture were isolated from 111 of the specimens that contained anaerobic bacteria. Common isolated included Actinomyces (9.1%), Clostridium perfringens (19.3%), other Clostridium spp (11.2%), Peptostreptococcus anaerobius (7.5%), Bacteroides melaninogenicus (13.4%), other Bacteroides spp (17.6%), and Fusobacterium necrophorum (5.3%). Anaerobic bacteria were involved in serious lesions that often were life threatening to the animals. Antibiotic susceptibility data indicated that the lincomycin family, the penicillin family, chloramphenicol, and cephaloridine are preferred drugs for treatment of anaerobic infections. Data from the survey were used in formulation of a table to aid practitioners in clinical diagnosis of disease caused by anaerobes. Clostridium perfringens was isolated in large numbers from five of six dogs with a clinical diagnosis of canine hemorrhagic gastroenteritis and from one cat with hemorrhagic diarrhea. Experimental infections were induced in rats, using caine feces as inoculum. Induced lesions contained aerobic and anaerobic bacteria similar to those bacteria isolated in the clinical survey, indicating that feces may serve as a major source of these bacteria in clinical infections of the dog.

Animals↗

PubMedDate not supplied

Characterization of a gram-positive bacterium from the proventriculus of budgerigars (Melopsittacus undulatus).

The cellular, cultural, and biochemical characteristics of eight isolates of a large gram-positive bacillus that are commonly observed as apparently normal flora in the proventriculus of budgerigars (Melopsittacus undulatus) were determined. The bacterium was highly pleomorphic and changed markedly in both diameter and length when subcultured on agar media. The bacterium was facultative anaerobic and capnophilic, hemolytic on blood agar, and formed flat colonies with irregular edges after incubation for several days. All isolates grew on sodium azide agar but did not grow on MacConkey agar. The isolates were catalase-negative and oxidase-negative and did not reduce nitrate. All isolates failed to utilize arginine, lysine, ornithine or tryptophane but produced acid from glucose, galactose, levulose, maltose, melibiose, starch, and sucrose. All isolates produced acetoin from glucose and hydrolyzed esculin. The eight isolates could not be identified to either genus or species level based on the descriptions of currently classified organisms in the division Firmicutes as described in Bergey's Manual of Systematic Bacteriology.

Animals↗

PubMedDate not supplied

Competitive exclusion of Salmonella enteritidis in Leghorn chicks: comparison of treatment by crop gavage, drinking water, spray, or lyophilized alginate beads.

The protective effect of cecal bacteria cultures on Salmonella enteritidis cecal colonization was evaluated. Competitive-exclusion cultures were administered by crop gavage, in first drinking water, by whole body spray, or encapsulated in alginate beads and provided in feed pans. Leghorn chicks were treated with cultures of cecal bacteria on the day of hatch and challenged orally with 10(4) S. enteritidis 2 days after treatment. Salmonella cecal colonization was evaluated 7 days after challenge. No Salmonella organisms were detected in the ceca of chicks treated with cecal cultures by crop gavage. Chicks treated with cecal cultures in the drinking water or by spray application showed comparable protection and significant decreases (P < 0.05) in the number of Salmonella in the cecal contents compared with untreated controls. The consumption of cecal bacteria encapsulated in alginate beads significantly decreased (P < 0.05) Salmonella cecal colonization compared with control treatment, but it provided less protection than the other treatment methods evaluated.

Administration, Oral↗

PubMedDate not supplied

Effect of a defined continuous-flow derived bacterial culture and dietary lactose on Salmonella typhimurium colonization in broiler chickens.

A defined bacterial culture protective against Salmonella typhimurium cecal colonization in broiler chicks was derived utilizing a continuous-flow (CF) culture apparatus. Chicks receiving the CF culture in combination with a diet containing dietary lactose were protected against cecal colonization by S. typhimurium. The culture consisted of a mixture of gram-positive and gram-negative facultative and strictly anaerobic bacteria. The isolates were identified as Enterococcus avium, two strains of Enterococcus faecalis (designated A and B), Lactococcus lactis, Lactobacillus animalis, a Lactobacillus that could not be identified to species level (designated strain CMS), Citrobacter freundii, Escherichia coli, E. fergusonii, Bifidobacterium animals, and Propionibacterium acidipropionici. Results indicated that CF cultures can be used as a tool to identify bacteria which are antagonistic to S. typhimurium in the chick cecum.

Animal Feed↗