PubMed Health⌕ Search

Biomedical subjects

C M Scanlan

Publications and source records attributed to C M Scanlan.

At least 19 recordsLinked to original sources
PubMed1995

Fermentation of radiolabelled substrates by batch cultures of caecal microflora maintained in a continuous-flow culture.

Glucose- and lactose-based media containing either 14C-labelled glucose, galactose, lactose or lactic acid were inoculated with anaerobic cultures of chicken caecal bacteria maintained for 121 d in a continuous-flow (CF) culture. The culture was previously shown to reduce Salmonella colonization in the caeca of chicks inoculated with the culture and the reduction was associated with increases in volatile fatty acids. The distributions of 14C were determined among the fermentation products, especially acetic, propionic and lactic acids. After 12 h of incubation and fermentation, variations were observed in the total amounts of 14C, from each 14C-labelled substrate, detected as acetic and propionic acids in the glucose- and lactose-based media, respectively: 92.9 and 89.4% of 14C-glucose, 77.0 and 44.0% of 14C-galactose, 0.0 and 76.9% of 14C-lactose, and 76.5 and 93.2% of lactic acid in the two media, respectively. The results from this study indicate that carbohydrate metabolism by the CF culture was a major source of acetic and propionic acids and that lactic acid was an important metabolic intermediate for the synthesis of the volatile fatty acids.

Animals↗
PubMed1995

Control of Salmonella typhimurium colonization in broiler chicks with a continuous-flow characterized mixed culture of cecal bacteria.

A continuous-flow culture system was used to isolate and maintain a mixed culture of cecal bacteria from adult broilers composed of 29 bacterial strains representing 10 genera. Broiler chicks were treated with the mixed culture in the drinking water on the day of hatch and challenged orally with 10(4) Salmonella typhimurium 2 d after treatment. The experiment was repeated in four separate trials using newly hatched chicks. The concentration of propionic acid and total volatile fatty acid (VFA) in the cecal contents was determined 2 d after treatment and at 10 d of age. Compared with controls, the number of treated chicks that were cecal culture-positive for Salmonella decreased (P < .01) in each of the trials. Additionally, the number of Salmonella in the cecal contents of the treated chicks at 10 d of age was decreased (P < .005) compared with controls in each trial. The decreased number of Salmonella in the cecal contents of the 10-d-old treated chicks was correlated with elevated concentrations of propionic acid (P < .05) and total VFA (P < .1) in the cecal contents of the treated chicks 2 d after treatment. The results indicated that VFA-producing bacteria present in the mixed culture became rapidly established in the ceca of the treated chicks and effectively increased resistance to S. typhimurium challenge.

Animals↗
PubMed1995

Treatment of commercial broiler chickens with a characterized culture of cecal bacteria to reduce salmonellae colonization.

The effect of treatment with a newly developed characterized continuous-flow (CCF) culture composed of 29 strains of cecal bacteria on salmonellae colonization was evaluated in commercially reared broiler chickens. Newly hatched chicks in three flocks were sprayed with CCF culture as they were placed in rearing houses and compared with untreated flocks on the same farm. Hatchery transport tray liners and rearing house feed, water, and little samples were cultured for the presence of salmonellae. Cecal samples were cultured after 3- and 6-wk growout. Skin-feather samples were cultured at 6-wk growout. Fifty-five percent of the transport tray liners were contaminated with salmonellae on the day of chick placement. At 3 wk, salmonellae serotypes present on the tray liners were widely distributed in the litter of the rearing houses. The results indicated that exposure to salmonellae occurred before culture treatment and continued in the rearing houses during the 6-wk growout period. Salmonellae cecal colonization was decreased (P < .05) in two of the treated flocks at 3 wk and diminished (P < .07) in the third treated flock compared with control flocks. At 6 wk, skin-feather contamination and cecal colonization were decreased (P < .05) in one of the treated flocks whereas no treatment effect occurred in two of the treated flocks compared with controls. The results clearly indicate the necessity of implementing integrated programs to control salmonellae in both the hatchery and rearing house environments. The CCF culture served to enhance salmonellae colonization resistance and may serve as a useful component of an integrated control program.

Animals↗
PubMed1995

Fermentation of radiolabeled carbohydrates by a reconstructed continuous-flow culture effective against Salmonella in broiler chicks.

An 81-d-old continuous-flow (CF) culture of broiler cecal bacteria was maintained in a lactose-based broth. The culture had been previously proven effective against Salmonella colonization in young chicks, especially when the chicks were provided dietary lactose. Portions of the CF culture were batch-cultured in glucose- and lactose-based broths containing 14C-labeled lactose, glucose, galactose, or lactic acid to determine the effect of media carbohydrate on fermentation products. Acetic and propionic acids were the major 14C-labeled fermentation products. 14C-Carbohydrates were fermented to lactic acid and then to acetic and propionic acids. Distribution of radiolabeled fermentation products was effected by the broth carbohydrate and the time postinoculation.

Acetates↗
PubMed1994

Effect of dietary lactose and cell concentration on the ability of a continuous-flow-derived bacterial culture to control Salmonella cecal colonization in broiler chickens.

The effect of dietary lactose and of cell concentration of a continuous-flow (CF) derived bacterial culture on Salmonella typhimurium cecal colonization in 10-d-old broiler chickens was examined. One-day-old chicks were provided 1) no CF culture and the control diet; 2) no culture and a 2% lactose diet; 3) CF culture (10(8) or 10(11) anaerobic cfu) and control diet; or 4) CF culture (10(8) or 10(11) anaerobic cfu) and 2 to 4% lactose diet. All groups were challenged orally with 10(4) S. typhimurium at 3 d of age. Salmonella typhimurium growth in cecal contents was significantly decreased (P < .05) at 10 d of age when 2% lactose was used in combination with CF culture containing 10(8) or 10(11) anaerobic cfu. The protection factor (log10 Salmonella control diet divided by log10 Salmonella treatment group) for these treatment groups was 2.49 and 9.26, respectively. Results indicate that birds treated with CF culture and maintained on 2% dietary lactose are protected against S. typhimurium colonization. Additionally, inoculating birds with CF culture containing a higher concentration of anaerobic colony-forming units resulted in a substantially higher protection factor.

Animals↗
PubMed1994

Resistance against Salmonella enteritidis cecal colonization in Leghorn chicks by vent lip application of cecal bacteria culture.

Leghorn chicks were treated with cultures of cecal bacteria from adult chickens by crop gavage, upper body spray, or vent lip application on the day of hatch. The chicks were challenged orally with 10(4) Salmonella enteritidis (SE) at 3 d of age and evaluated for SE cecal colonization at 10 d of age. The concentration of volatile fatty acids (VFA) in the cecal contents was determined on the day after culture treatment and at 10 d of age. Compared with controls, SE colonization was significantly decreased in each of the treatment groups. Vent lip application of a single .05-mL drop of cecal bacteria culture resulted in resistance against SE challenge comparable to crop gavage or spray treatment with .5 mL of culture. Resistance to SE challenge was directly associated with the concentrations of total VFA and propionic acid in the cecal contents of the treated chicks on the day after culture treatment. The results indicated that cecal bacteria from adult chickens that increase SE colonization resistance may rapidly become established in the ceca of newly hatched chicks following contact with the vent lips.

Administration, Rectal↗
PubMed1993

Research note: differential chemotaxis of Physarum polycephalum to Salmonella gallinarum and Salmonella pullorum.

The chemotactic and chemotropic responses of the plasmodial stage of the slime mold Physarum polycephalum were used to distinguish Salmonella gallinarum and Salmonella pullorum from 10 Salmonella serovars that are commonly isolated from domestic poultry. Utilizing an in vitro plasmodium agar plate assay method, P. polycephalum was attracted to S. gallinarum and S. pullorum, but the organism was repelled by Salmonella derby, Salmonella dublin, Salmonella enteritidis, Salmonella heidelberg, Salmonella minnesota, Salmonella montevideo, Salmonella newington, Salmonella newport, Salmonella reading, and Salmonella typhimurium.

Animals↗
PubMed1993

Development of defined cultures of indigenous cecal bacteria to control salmonellosis in broiler chicks.

An in vitro continuous-flow (CF) culture system was utilized to isolate and maintain a defined mixed culture of indigenous cecal bacteria from adult broilers. The protective effects of the defined CF culture and dietary lactose on Salmonella typhimurium colonization were evaluated in broiler chicks. The CF culture was administered to chicks by crop gavage on the day of hatch. Lactose was provided as 5% (wt/wt) of the feed ration. The chicks were challenged orally with 10(4) S. typhimurium at 3 days of age and evaluated for Salmonella colonization 7 days after challenge. The experiment was repeated in six separate trials using newly hatched chicks and CF culture that was maintained in continuous steady-state conditions from 42 to 190 days. Compared with controls, the mean number of S. typhimurium in the cecal contents of the chicks given CF culture and dietary lactose decreased significantly (P < .01) by 4.2 log10 units. Similarly, the numbers of Salmonella cecal culture-positive chicks was significantly decreased (P < .01) by 55% in the chicks given CF culture and lactose. The results indicated that a defined culture of indigenous cecal bacteria isolated and maintained in CF culture, together with dietary lactose, effectively controlled S. typhimurium cecal colonization in newly hatched broiler chicks.

Animals↗
PubMed1993

In vitro metabolism of radiolabeled carbohydrates by protective cecal anaerobic bacteria.

Cecal anaerobic bacteria from adult broilers were cultured in media containing .25% glucose or .25% lactose. Media also contained either [14C]-labeled lactose, glucose, galactose, or lactic acid as metabolic tracers. Cultures were analyzed at 4, 8, and 12 h for pH, radiolabeled and unlabeled volatile fatty acids, and lactic acid. The pH values of cultures containing .25% lactose were significantly (P < .05) higher than the pH values of cultures containing .25% glucose. Lactose cultures reached their lowest pH more slowly than glucose cultures. Concentrations of unlabeled volatile fatty acids increased and lactic acid decreased during incubation of the cultures. Radiolabeled sugars and lactic acid were more readily metabolized to volatile fatty acids in media containing lactose than in media containing glucose. The preferred metabolism of [14C]substrates, independent of media carbohydrate, was in the following order: lactic acid > galactose, lactose > glucose. The volatile fatty acids in which radiolabel was most concentrated were acetic acid, propionic acid, or butyric acid.

Animals↗
PubMed1993

Combined enzyme and antimicrobial susceptibility profiles of caprine Pasteurella haemolytica serovar 2 respiratory tract isolates.

The present investigation describes a novel method of demonstrating strain diversity among Pasteurella haemolytica biovar A, serovar 2 (PhA2) nasal turbinate isolates from a flock of 32 experimental goats during a naturally occurring outbreak of pasteurellosis. After a 21 day conditioning period in a feedyard, 51 PhA2 isolates from 27 culture-positive goats were identified including 1 on day 22, 14 on day 25, 21 on day 39, and 15 on day 66. Each PhA2 isolate was evaluated for its enzyme activity against 19 substrates with a commercial semiquantitative enzyme system and for its antimicrobial susceptibility with 12 drugs, resulting in 7 different enzyme profiles and 8 different antimicrobial susceptibility profiles. A total of 14 combined enzyme and antimicrobial susceptibility profiles were produced. The same PhA2 strain was isolated from only 4 of the 12 goats with 2 PhA2 isolations, while the same PhA2 strain was isolated from only 1 of the 6 goats with 3 PhA2 isolations. The data from this investigation demonstrated that the PhA2 upper respiratory tract flora from goats is highly heterologous.

Animals↗
PubMed1993

Identification of Pasteurella haemolytica A1 isolates from market-stressed feeder calves by use of enzyme and antimicrobial susceptibility profiles.

An epidemiologic study of Pasteurella haemolytica serovar 1 (Ph1) in market-stressed feeder calves from 7 farms in eastern Tennessee was conducted. The nasal mucus of each calf was cultured sequentially at the farm of origin (day 0), at an auction market (day 133), and at a feedyard in Texas (days 141, 148, 155, and 169). Of the 103 calves tested, 77 were culture-positive, including 1 on day 0, 1 on day 133, 20 on day 141, 57 on day 148, 50 on day 155, and 14 on day 169. From the 143 Ph1 isolates, 20 enzyme profiles were determined by use of a commercial enzyme system that detects 19 enzymatic reactions; 4 antimicrobial susceptibility profiles were obtained, using the disk-diffusion method, which evaluated susceptibility to 11 antibacterial drugs. All isolates were positive for acid phosphatase and alkaline phosphatase, but were negative for alpha-galactosidase, alpha-mannosidase, beta-glucosidase, beta-glucuronidase, cystine aminopeptidase, N-acetyl-beta-glucosaminidase, and trypsin. Other positive enzyme reactions included: leucine aminopeptidase, 140 Ph1 isolates; phosphohydrolase, 90 isolates; alpha-fucosidase, 63 isolates; esterase (C4), 59 isolates; valine aminopeptidase, 30 isolates; esterase lipase (C8), 24 isolates; beta-galactosidase, 2 isolates; and alpha-glucosidase, chymotrypsin and lipase (C14), 1 isolate each. Thirty-four Ph1 profiles were identified, using combined enzyme and antimicrobial susceptibility profiles. The data indicate that the strains isolated during the feedyard period may have been determined more by farm of origin (P < or = 0.001) than by habitation with calves from other farms while in the feedyard.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Bacteriologic and pathologic studies of hepatic lesions in sheep.

At an abattoir, lesion specimens from 140 condemned sheep livers were collected for bacteriologic culture and for pathologic examination. Grossly, 23 lesions were abscesses; from 9 of which, Fusobacterium necrophorum biovar A (3 in pure culture and 6 in mixed culture) was isolated and from 14 of which, biovar B (6 in pure culture and 8 in mixed culture) was isolated. Escherichia coli was the predominant facultative anaerobic bacterium and Clostridium perfringens was the predominant obligate anaerobic bacterium isolated from the 14 lesions with mixed bacterial infection. Histologically, these lesions had a core of coagulation necrosis, encircled by a zone of necrotic phagocytic cells and bacteria with cellular characteristics of F necrophorum biovars A or B, and a connective tissue capsule. Of the 117 lesions without F necrophorum, 49 were culture-positive (for other organisms) and 69 were culture-negative. These 117 lesions were fibrous and were smaller than the 23 abscesses. A variety of gram-positive and gram-negative facultative anaerobic and obligate anaerobic bacteria was isolated from the culture-positive lesions, but always in low numbers. Eleven culture-negative and 18 culture-positive lesions were examined and had histologic characteristics of parasite-induced granulomas, with numerous eosinophils and epithelioid giant cells. Results of the study indicated that the histologic appearance of ovine hepatic lesions with F necrophorum was similar to bovine liver abscesses caused by F necrophorum, but unlike bovine liver abscesses, F necrophorum biovar B was isolated more frequently than was biovar A and often in pure culture. Most of the lesions in the condemned livers were parasite-induced granulomas.

Animals↗
PubMed1989

A bacteriologic study of scabby-hip lesions from broiler chickens in Texas.

Broilers from commercial flocks experiencing a 10-60% incidence of scabby-hip lesions at processing were examined, and selected skin lesions were cultured. Over 70% of the lesions were associated with traumatic excoriations, particularly on the caudal dorsal convexity of the birds. Most lesions were observed on birds that were 5 weeks of age or older. From the 27 specimens cultured, Clostridium perfringens was isolated in pure culture from 4 lesions and Staphylococcus species from 10 lesions. Pure cultures of staphylococci were recovered from 4 lesions, and 2-5 different staphylococci were isolated from 6 lesions. Eight staphylococci were identified as S. sciuri, 8 as S. simulans, 2 as S. epidermidis, 2 as S. lentus, 2 as S. warneri, 1 as S. cohnii, and 1 as S. intermedius. Fifty cutaneous specimens from 10 5-week-old normal broilers were cultured. A total of 197 isolates were identified including 65 S. sciuri, 52 S. lentus, 24 S. simulans, 12 S. hyicus, 11 S. warneri, 9 S. cohnii, 9 S. gallinarium, 8 S. xylosus, and 7 S. epidermidis.

Animals↗
PubMed1989

Cultural and biochemical characterization of Actinobacillus and Actinobacillus-like species from ram lambs with epididymitis.

Cellular, colonial, cultural, and biochemical characteristics of 25 field strains of gram-negative pleomorphic bacilli from rams with epididymitis were compared with Actinobacillus actinomycetemcomitans American Type Culture Collection (ATCC) strain 29522 and Actinobacillus seminis ATCC strain 15768. Three field strains were identified as A. actinomycetemcomitans, 15 as A. seminis, and 2 as Haemophilus agni; however, 5 strains (3 in group A and 2 in group B) were not identified as species in the genera Actinobacillus, Haemophilus, or Pasteurella based on the taxonomic criteria in Bergey's manual of systematic bacteriology. The 5 Actinobacillus-like organisms in groups A and B were predominantly gram-negative coccobacilli and exhibited less pleomorphism than the 2 Actinobacillus species. The colonial morphologies of groups A and B were similar to the 2 Actinobacillus species but were smaller in diameter and had a pale yellow color. Groups A and B, like the actinobacilli, were facultative anaerobic and capnophilic, did not grow on MacConkey agar, and were catalase-positive and oxidase-positive. Group A reduced nitrate but group B did not. The A. seminis strains utilized ornithine, and group A utilized arginine; but group B did not utilize either ornithine or arginine. All strains failed to utilize lysine or tryptophane. All strains produced acid but no gas from glucose, and the utilization of other carbohydrates varied markedly both between and within the 5 groups of bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinobacillus↗