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Increase of mannose residues, as Salmonella typhimurium-adhering factor, on the cecal mucosa of germ-free chickens infected with Eimeria tenella
1993
Baba, W. | Tsukamoto, Y. | Fukata, T. | Sasai, K. | Arakawa, A.
To study increase of the Salmonella population in the cecum of chickens infected with Eimeria tenella, quantitative changes in mannose residues on the cecal mucosa were investigated. Inhibition of S typhimurium adherence to the cecum by a 2% carbohydrate (D-mannose, D-galactose, L-fucose, alpha-methyl-D-glucoside) in phosphate-buffered saline solution was examined. Only D-mannose had inhibitory effects. Whereas, D-galactose had somewhat enhancing effects on adherence of S typhimurium to the cecal mucosa of uninfected germ-free chickens. In infected and uninfected chickens, D-mannose inhibited adherence of S typhimurium. D-mannose significantly (P < 0.05) increased adherence of Bacteroides sp. In infected and uninfected chickens, D-mannose did not have any effect on adherence of Clostridium perfringens and Bifidobacterium thermophilum. Under microscopic observation, only concanavalin A and Lens culinaris agglutinin, of 8 lectins examined, were recognized as lectin-positive staining lines or spots in the cecal mucosa, indicating presence of mannose residues on the cecal mucosa. In E tenella-infected chickens, lectin-positive staining was seen strongly on the coarse surface of damaged cells and at the bottom of the crypts. These results indicate that coccidial infection may induce increase of mannose residues on the intestinal surface and allow adhesion of more salmonellae to the intestine.
Show more [+] Less [-]Enterotoxigenic, verotoxigenic, anda necrotoxigenic Escherichia coli isolated from cattle in Spain
1993
Blanco, M. | Blanco, J. | Blanco, J.E. | Ramos, J.
To assess the role of enterotoxigenic (ETEC), verotoxigenic (VTEC), and necrotoxigenic (NTEC) Escherichia coli in cattle with diarrhea, 1,524 colonies of E coli isolated from 197 calves with diarrhea and from 112 healthy controls were investigated for production of heat-labile and heat-stable enterotoxins, verotoxins, and cytotoxic necrotizing factors (CNF1 and CNF2). The ETEC were isolated from only 2 (1%) calves with diarrhea and from 5 (4%) healthy controls. In contrast, VTEC and NTEC that produced CNF2 were frequently identified. The VTEC were isolated from 18 (9%) calves with diarrhea and from 21 (19%) healthy cattle (P < 0.05), whereas NTEC that produced CNF2 were detected in 39 (20%) ill calves and in 38 (34%) controls (P < 0.01). Therefore, VTEC and NTEC that produced CNF2 were isolated significantly more frequently from healthy than diseased calves. Serogroups to which VTEC belonged differed considerably from the O groups involved with NTEC. Although, VTEC belonged to 18 serogroups, only 4 (O26, O103, O113, and O157) accounted for 56% (25 of 45) of verotoxigenic strains. The NTEC that produced CNF2 belonged to 26 serogroups; however, 64% (69 of 108) were from 6 serogroups (O1, O3, O15, O55, O88, and O123). Our results are compatible with cattle being a reservoir of VTEC that are pathogenic for human beings and with ETEC being an unusual cause of bovine colibacillosis in Galicia (northwestern Spain). Furthermore, results of this study indicate that VTEC and NTEC that produced CNF2 may be part of the normal intestinal flora of cattle.
Show more [+] Less [-]Serum interleukin-6 concentrations in endotoxin-infused neonatal foals
1993
Robinson, J.A. | Allen, G.K. | Green, E.M. | Garner, H.E. | Loch, W.E. | Walsh, D.M.
Serum interleukin-6 (IL-6) concentration was measured in 11 colostrum-fed (CF) and 8 colostrum. deprived (CD) 2- to 3-day-old foals after foals were infused with lipopolysaccharide LPS; Escherichia coli O55:B5 endotoxin, 0.5 micrograms/kg of body weight in sterile saline [0.9% NaCl] solution. Four CF and 2 CD foals were given saline solution alone. Serum IL-6 concentration was estimated by use of an in vitro proliferative bioassay, using the IL-6 dependent B.13.29 clone 9 cells. Interleukin-6 concentration increased in all LPS-infused foals, and geometric mean serum IL-6 concentration was significantly higher in CF than CD foals 30 and 90 minutes after infusion. Both LPS-infused. groups had multiple spikes of mean IL-6 concentration that peaked at 120 minutes in CF foals and 150 minutes in CD foals. Results indicated that IL-6 is produced in neonatal foals in response to LPS infusion. Furthermore, colostrum deprivation resulted in longer times to peak mean serum IL-6 concentration and tended to reduce serum IL-6 concentration in neonatal foals.
Show more [+] Less [-]Ground reaction force patterns of Dutch Warmbloods at the canter
1993
Merkens, H.W. | Schamhardt, H.C. | Osch, G.J.V.M. van | Hartman, W.
Ground reaction force (GRF) patterns from 20 clinically sound Dutch Warmbloods were recorded at the right fore-leading canter, and a standard horse was composed. These GRF data for the standard can be used for evaluation of jumping horses. The GRF patterns were asymmetric for all 4 limbs. The leading right forelimb decelerated the body. The trailing left forelimb propelled the body and decelerated it slightly. The trailing left hind limb propelled, and the leading right hind limb contributed to deceleration and propulsion. Referred to the maximal vertical load of the leading right forelimb, the load of the trailing left forelimb was 25% more; the load of the right hind limb was slightly less, whereas the load of the left hind limb was about 80% of that value.
Show more [+] Less [-]Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats
1993
Center, S.A. | Guida, L. | Zanelli, M.J. | Dougherty, E. | Cummings, J. | King, J.
In this study, we compared hepatic ultrastructure in healthy cats, in cats with severe hepatic lipidosis, and in cats with experimentally induced, chronic, extrahepatic bile duct occlusion. Ultrastructural features unique to the lipidosis syndrome included an apparent reduction in number of peroxisomes and alteration in their morphologic features. The quantity of endoplasmic reticulum, Golgi complexes, and lysosomes was subjectively reduced, and paucity of cytosolic glycogen was observed. Bile canaliculi appeared collapsed because of cytosolic distention with lipid. Mitochondria were reduced in number and were markedly pleomorphic. Cristae assumed a variety of shapes, lengths, and orientations. Ultrastructural features of bile duct occlusion were similar to those described in other species and differed from those in cats with hepatic lipidosis.
Show more [+] Less [-]Characterization of newly isolated plasmids from Actinobacillus pleuropneumoniae
1993
Ishii, H. | Fukuyasu, T. | Iyobe, S. | Hashimoto, H.
The genetic basis of drug-resistant strains of Actinobacillus pleuropneumoniae in Japan was studied. The A pleuropneumoniae strains AV277 and AV281 that belong to serotype 2 were resistant to streptomycin (SM) and sulfonamide (SA). Both strains had an 8.1-kilobase (kb) SM-SA plasmid that was previously classified in the H1 group. The AV177 (serotype 1) strain was resistant to SM, SA, ampicillin, and kanamycin (Km), but did not have any plasmids. The AV319 and AV324 (serotype 1) strains were resistant to Sm, SA, tetracycline (TC), and chloramphenicol (CP). The AV318 (serotype 12) strain was resistant to SM, SA, TC, minocycline, and CP. These 3 strains (AV319, AV324, and AV318) had a 4.3-kb SM-SA plasmid and a 5.2-kb CP plasmid. The 4.3-kb plasmid was classified in the H2 group. The AV263 (serotype 1) strain was resistant to SM, SA, KM, TC, and CP. It had a 5.2-kb CP plasmid and a 6.6-kb SM-SA-KM plasmid. Both plasmids did not replicate stably in Escherichia coli strains. The former 5.2-kb plasmid was mobilized in E coli strains by plasmid RP4, which belonged to incompatibility P with broad host range, but the latter 6.6-kb plasmid was not so mobilized. Three 5.2-kb CP plasmids isolated from strains AV319, AV324, and AV318, had the same restriction endonuclease pattern after digestion with Ava I and EcoRI. They coexisted with H1 group plasmids in the incompatibility test, and coexisted also with H2 group plasmids of the original A pleuropneumoniae strains. Results indicated that the 5.2-kb CP plasmids could be classified in a new incompatibility group, H3. In this study, 4 types of plasmids were isolated, but no plasmids encoded TC and minocycline resistance.
Show more [+] Less [-]Comparison of stressed simultaneous urethral pressure profiles between anesthetized continent and incontinent bitches with urethral sphincter mechanism incompetence
1993
Gregory, S.P. | Holt, P.E.
The popular urodynamic technique of stressed urethral pressure profilometry used for investigation of genuine stress incontinence in women was adapted and applied to bitches. The aim was to assess the suitability and reproducibility of the technique in the canine species, and to determine whether differences seen in continent and incontinent women were found in bitches. Resting and stressed simultaneous urethral pressure profiles were obtained for 25 continent and 25 incontinent bitches, the latter diagnosed as having urethral sphincter mechanism incompetence. The stressed urethral pressure profiles were produced by ballottement of the abdomen during catheter withdrawal. The degree of stress induced was consistent and had got short-term reproducibility. Highly significant (P < 0.001) differences in the percentage of negative spikes extending below the resting intravesical pressure were found between continent and incontinent bitches. Significant differences were not observed in the pressure transmission profiles between continent and incontinent bitches; both groups had a gradual decrease in pressure transmission from the bladder neck to the external urethral orifice. The distance from the start of the urethral pressure profile to the first negative peak (attributable to respiration or ballottement) on the subtracted profile was compared with the radiographic distance that the bladder neck was positioned with respect to the cranial pubic brim, taking body weight and continence status into account. Body weight and continence status did not have significant effect on the relation in either instance. The distance between the start of the urethral pressure profile and the first negative peak induced by respiration was significantly (P < 0.05) related to the bladder neck position with respect to the cranial pubic brim, although it accounted for little of the total variance. Relation between the same variables during stressed urethral pressure profilometry, induced by abdominal ballottement, was not significant.
Show more [+] Less [-]Detection of bluetongue virus from blood of infected sheep by use of an antigen-capture enzyme-linked immunosorbent assay after amplification of the virus in cell culture
1993
Mecham, J.O.
An antigen-capture ELISA was used to detect bluetongue virus (BTV) from blood of infected sheep. A rabbit-origin capture antibody and a mouse-origin detection antibody combined with biotin-avidin amplification were used for the assay. The antigen-capture ELISA could not detect virus directly from the blood of infected sheep because of low virus titer. To enhance detection, virus from infected blood was amplified in cell culture. Virus could then be detected from cell culture supernatant fluids, using the ELISA. This amplification step increased the sensitivity of the assay comparable to that of assays performed in cell culture measuring cytopathic effects. The ELISA procedure was specific for BTV and did not mistakenly identify the antigenically related epizootic hemorrhagic disease virus. The antigen-capture ELISA permitted indirect quantitation and identification of BTV from the blood of infected sheep.
Show more [+] Less [-]Prevention of cisplatin-induced nephrotoxicosis in dogs, using hypertonic saline solution as the vehicle of administration
1993
Forrester, S.D. | Fallin, E.A. | Saunders, G.K. | Kenny, J.E.
We determined whether administration of cisplatin in hypertonic saline solution would prevent significant decrease in renal function, as measured by exogenous creatinine clearance, in healthy dogs. A single dose of cisplatin (70 mg/m2 of body surface) was mixed in 3% saline solution and was infused IV (6.5 ml/kg of body weight) over a 20-minute period to 6 healthy dogs. Exogenous creatinine clearance was determined prior to treatment of dogs with cisplatin and again on days 3 and 21 after administration of cisplatin. All 6 dogs vomited at least once within 12 hours of treatment with cisplatin; however, clinically important changes in appetite, body weight, or hydration status were not apparent during the 21-day study. Although mean values for exogenous creatinine clearance decreased from baseline on days 3 and 21, changes were not significantly different. Renal histologic lesions included mild, chronic, lymphoplasmacytic interstitial nephritis in 5 dogs, and presumably, were unrelated to treatment with cisplatin. Mild renal tubular atrophy (n = 2) and tubular necrosis (n = 1) may have developed secondary to treatment with cisplatin. Results of this study indicated that administration of a single dose of cisplatin in 3% saline solution to healthy dogs was not associated with significant decrease in glomerular filtration rate. This is a convenient protocol for administering cisplatin; however, additional study is required before it can be recommended for clinical patients, especially those with preexisting renal disease or those receiving multiple doses of cisplatin.
Show more [+] Less [-]Alterations in the arrhythmogenic dose of epinephrine after xylazine or medetomidine administration in isoflurane-anesthetized dogs
1993
Lemke, K.A. | Tranquilli, W.J. | Thurmon, J.C. | Benson, G.J. | Olson, W.A.
Eight dogs (body weight, 12.5 to 21.5 kg) were assigned at random to each of 3 treatment groups (IS, IX, IM) that were not given glycopyrrolate and to each of 3 groups that were given glycopyrrolate (IGS, IGX, IGM). Dogs, were anesthetized with isoflurane (1.95% end-tidal concentration), and ventilation was controlled (PCO2, 35 to 40 mm of Hg end-tidal concentration). Glycopyrrolate was administered IV and IM at a dosage of 11 micrograms/kg of body weight, each. Saline solution, xylazine (1.1 mg/kg, IM), or medetomidine (15 micrograms/kg, IM) was administered 10 minutes after baseline ADE determination. Redetermination of the ADE at the same infusion rate was started 10 minutes after drug administration. Arrhythmogenic dose was determined by constant infusion of epinephrine at rates of 1.0, 2.5, and 5.0 micrograms/kg/min. The ADE was defined as the total dose of epinephrine that induced at least 4 ectopic ventricular depolarizations within 15 seconds during a 3-minute infusion, or within 1 minute after the end of the infusion. Total dose was calculated as the product of infusion rate and time to arrhythmia. Statistical analysis of the differences between baseline and treatment ADE values was performed by use of one-way ANOVA. Mean +/- SEM baseline ADE values for groups IS, IX, and IM were 1.55 +/- 0.23, 1.61 +/- 0.28, and 1.95 +/- 0.65 micrograms/kg, respectively. Differences for groups IS, IX, and IM were -0.12 +/- 0.05, -0.31 +/- 0.40, and -0.17 +/- 0.26, respectively. Differences for groups IGS, IGX, and IGM could not be calculated because arrhythmias satisfying the ADE criteria were not observed at the maximum infusion rate of 5.0 micrograms/kg/min. Differences among groups IS, IX, and IM were not significant. We conclude that in isoflurane-anesthetized dogs: preanesthetic dosages of xylazine (1.1 mg/kg, IM) or medetomidine (15 micrograms/kg, IM) do not enhance arrhythmogenicity, and at these dosages, there is no difference in the arrhythmogenic potential of either alpha 2-adrenergic receptor agonist.
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