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Large intestinal capacity, retention times, and turnover rates of particulate ingesta associated with extensive large-colon resection in horses.
1989
Bertone A.L. | VanSoest P.J. | Johnson D. | Ralston S.L. | Stashak T.S.
Metagenomic analysis of acquired antibiotic resistance determinants in the gut microbiota of wild boars (Sus scrofa) – preliminary results
2020
Libisch, Balázs | Keresztény, Tibor | Kerényi, Zoltán | Kocsis, Róbert | Sipos, Rita | Papp, Péter P. | Olasz, Ferenc
Land application of manure that contains antibiotics and resistant bacteria may facilitate the establishment of an environmental reservoir of antibiotic-resistant microbes, promoting their dissemination into agricultural and natural habitats. The main objective of this study was to search for acquired antibiotic resistance determinants in the gut microbiota of wild boar populations living in natural habitats. Gastrointestinal samples of free-living wild boars were collected in the Zemplén Mountains in Hungary and were characterised by culture-based, metagenomic, and molecular microbiological methods. Bioinformatic analysis of the faecal microbiome of a hunted wild boar from Japan was used for comparative studies. Also, shotgun metagenomic sequencing data of two untreated sewage wastewater samples from North Pest (Hungary) from 2016 were analysed by bioinformatic methods. Minimum spanning tree diagrams for seven-gene MLST profiles of 104 E. coli strains isolated in Europe from wild boars and domestic pigs were generated in Enterobase. In the ileum of a diarrhoeic boar, a dominant E. coli O112ab:H2 strain with intermediate resistance to gentamicin, tobramycin, and amikacin was identified, displaying sequence type ST388 and harbouring the EAST1 toxin astA gene. Metagenomic analyses of the colon and rectum digesta revealed the presence of the tetQ, tetW, tetO, and mefA antibiotic resistance genes that were also detected in the gut microbiome of four other wild boars from the mountains. Furthermore, the tetQ and cfxA genes were identified in the faecal microbiome of a hunted wild boar from Japan. The gastrointestinal microbiota of the free-living wild boars examined in this study carried acquired antibiotic resistance determinants that are highly prevalent among domestic livestock populations.
Mostrar más [+] Menos [-]Effects of dietary supplementation of fructo-oligosaccharides on small intestinal bacterial overgrowth in dogs
1994
Willard, M.D. | Simpson, R.B. | Delles, E.K. | Cohen, N.D. | Fossum, T.W. | Kolp, D. | Reinhart, G.
Sixteen IgA-deficient German Shepherd Dogs with small intestinal bacterial overgrowth were randomized into 2 groups. One group was fed a chicken-based kibble diet; the other was fed the same diet, but with 1% fructo-oligosaccharides supplemented at the expense of cornstarch. After being exposed to the diets for 46 to 51 days, the group that ate the supplemented diet had significantly (P = 0.04) fewer aerobic/facultative anaerobic bacterial colony-forming units in fluid from the duodenum/proximal part of the jejunum, as well as in the duodenal mucosa. We could not detect significant differences in the species of bacteria found in the intestine of these 2 groups of dogs. We conclude that at least some dietary carbohydrates can affect small intestinal bacterial populations in dogs with small intestinal bacterial overgrowth.
Mostrar más [+] Menos [-]Experimental model of hypochloremic metabolic alkalosis caused by diversion of abomasal outflow in sheep
1990
Smith, D.F. | Lunn, D.P. | Robinson, G.M. | McGuirk, S.M. | Nordheim, E.V. | MacWilliams, P.S.
Hypochloremic metabolic alkalosis accompanied by hypokalemia and hyponatremia was induced experimentally in 7 adult sheep by diversion (loss) of gastric contents through an Ivan and Johnston cannula placed in the cranial part of the duodenum just distal to the pylorus. Cannula placement was easily accomplished, and cannulae were tolerated well by the sheep. Volume of effluent produced during the 60- to 120-hour period of diversion ranged from 7.7 to 14.9 L and tended to be greatest during the first 24 hours. All sheep became dehydrated, with mean PCV and plasma total protein concentration increases of 94.2 and 61.7%, respectively. Plasma chloride concentration decreased in linear fashion from a prediversion mean of 113 mEq/L (range, 111 to 117 mEq/L) to an end-point mean of 54 mEq/L (range, 45 to 65 mEq/L). Plasma sodium and potassium concentrations also decreased, though potassium concentration increased terminally. There were rapid increases in arterial blood pH and bicarbonate and base excess concentrations during the first 48 hours after diversion. However, during the final stages of diversion, sheep developed superimposed metabolic acidosis with increased plasma lactate concentration and high anion gap.
Mostrar más [+] Menos [-]Subgroup classification of porcine group-A rotaviruses, using monoclonal antibodies in an enzyme-linked immunosorbent assay
1990
Kassuba, A. | Saif, L.J. | Greenberg, H.B.
Fifty-six samples of feces and intestinal contents from nonvaccinated diarrheal pigs with rotavirus infections were tested, using a subgroup (SGP)-specific ELISA, to determine rotavirus SGP classification. Forty-one percent (23/56) were SGP 1, 25% (14/56) were SGP 2, and 34% (19/56) were not classifiable. For classifiable samples, the geographic distribution for SGP 1 and SGP 2, respectively was: 60%/40% from Ohio (n = 15), 63%/37% from other midwestern states (Iowa, Minnesota, Nebraska, South Dakota: n = 16), and 67%/33% from Canada (n = 6). Thirty-seven SGP-classifiable samples were categorized according to age of pigs. Of pigs less than or equal to 1 week old, 22% of samples were SGP 1 (n = 8), and 14% (n = 5) were SGP 2. Of samples from 1- to 2-week-old pigs, 8% were SGP 1 (n = 3), and 5% were SGP 2 (n = 2). Of samples from 2- to 3-week-old pigs, 5% were SGP 1 (n = 2), and 8% were SGP 2 (n = 3). Of samples from 3- to 4-week-old pigs, 5% were SGP 1 (n = 2), and 3% were SGP 2 (n = 1). Of samples from pigs > 4 weeks old, 22% were SGP 1 (n = 8) and 8% were SGP 2 (n = 3). Double-stranded RNA extracted from positive controls and from 10 selected field samples (5 from SGP 1 and 5 from SGP 2) was electrophoresed in polyacrylamide gels to detect correlation between subgroup classification by ELISA and long or short double-stranded RNA electrophoretic-migration patterns. All SGP-1 and -2 rotavirus samples tested had typical long double-stranded RNA electrophoretic-migration patterns.
Mostrar más [+] Menos [-]Detection of turkey enteric coronavirus by enzyme-linked immunosorbent assay and differentiation from other coronaviruses
1989
Dea, S. | Tijssen, P.
A double-antibody ELISA for the detection of coronaviruses in intestinal contents from turkey poults with diarrhea was developed. Antibodies were raised in rabbits and guinea pigs against a Minnesota isolate of turkey enteric coronavirus (TCV) propagated in embryonating turkey eggs and were purified by density-gradient centrifugation. The specificity of antisera was confirmed by hemagglutination-inhibition and immunoelectron microscopy. Absorption of anti-TCV hyperimmune sera with egg extracts or egg ovalbumin and the use of different dilution and blocking buffers influenced the sensitivity and specificity of the ELISA. Reciprocal cross-reactivity was detected among turkey, chicken, bovine, and murine coronaviruses. Antisera to the transmissible gastroenteritis virus of swine, the rabbit enteric coronavirus, or the human coronavirus strain 299E failed to react with TCV. The TCV cross-related only moderately with the avian infectious bronchitis virus and the hemagglutinating encephalomyelitis virus of swine. Investigations with samples from 47 commercial turkey flocks in Quebec with episodes of transmissible enteritis revealed that the ELISA was more sensitive than was electron microscopy for dectection of TCV.
Mostrar más [+] Menos [-]Large intestinal capacity, retention times, and turnover rates of particulate ingesta associated with extensive large-colon resection in horses
1989
Bertone, A.L. | VanSoest, P.J. | Johnson, D. | Ralston, S.L. | Stashak, T.S.
Fecal excretion of a particulate marker, ytterbium (Yb), was evaluated in 9 horses before surgery and 3 weeks, 3 months, and 6 months (4 trials) after sham-operation (group 1; n = 3) or extensive large colon resection (group 2; n = 6). Fecal excretion curves of total Yb excretion, log(e) Yb excretion, % Yb excretion, log(e) % Yb excretion, and cumulative % Yb excretion were evaluated, and kinectic analysis was performed on the log(e) Yb excretion curves to detect mixing pools and to calculate the fractional rate of particulate passage, turnover rate, and pool size. Calculations were performed to determined transit time, mean overall retention time, adjusted mean retention time, peak time, and disappearance time. Values were statistically analyzed to determine differences between groups and among trials (P less than 0.05). Group-2 horses had significantly shorter transit, peak, and mean overall retention times, compared with preoperative values and with values for group-1 horses. Two mixing pools were identified: a slower emptying pool of 5.7% hour-1 (k1) and a faster emptying pool of 12.3% hour-1 (k2). The rate of passage from the first pool (k1) was not altered by colon, resection, and was interpreted as being most influenced by the cecum. In further support of this interpretation, the capacity of the k1 pool approximated the capacity of the cecum (17 L). The capacity of the k1 pool significantly expanded by 6 months in the resected horses. The rate of passage from the second pool (k2) significantly increased initially after colon resection (3 weeks and 3 months), but returned to preoperative values by 6 months. This pool was affected by colon resection, and was therefore interpreted as being influenced by a portion of the colon. Despite these changes in rate of passage and capacity of the mixing pools, on all the trials, colon resection decreased intestinal transit time and overall mean retention time because of a decrease in the total large intestinal length or capacity. This decrease in particulate matter retention and transit time may partially or totally explain the decrease in fiber digestion reported in horses with extensive large colon resection.
Mostrar más [+] Menos [-]Evaluation of abomasal outflow diversion as an experimental model of hypochloremic, hypokalemic metabolic alkalosis in lactating cows
1994
Ward, J.L. | Smith, D.F. | Fubini, S.L. | Deuel-Aromando, D.M.