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Summary

A survey was conducted from 1986 through 1987, for which an ELISA was used to obtain information on the prevalence of Mycobacterium paratuberculosis infection in cattle of Florida. Results revealed prevalence of 8.6% in beef cattle and 17.1% in dairy cattle. In beef and dairy cattle, prevalence increased with increasing herd size. It was concluded that ELISA-detectable circulating antibodies to M paratuberculosis are widespread in cattle of Florida.

Free access
in Journal of the American Veterinary Medical Association

Summary

Members of the genus Salmonella were identified in feces from horses, using the polymerase chain reaction (pcr) and genus-specific oligonucleotide primers. Feces from healthy horses were determined to be culture-negative for Salmonella spp. Fecal samples were inoculated with known numbers of colony-forming units (cfu) of S anatum, S derby, S enteritidis, S heidelberg, S newport, and S typhimurium. The dna was extracted from fecal samples and amplified by pcr, using genus-specific primers. Sensitivity of the assay extended to 103 cfu of Salmonella sp/g of feces; sensitivity of microbiologic culture with enrichment extended to 102 cfu of Salmonella sp/g of feces. Feces that were not inoculated with Salmonella spp were negative by the pcr. Detection of salmonellae in feces was possible, using the pcr, within 10 to 12 hours from the time of submission of samples.

Free access
in American Journal of Veterinary Research

Summary

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.

Free access
in American Journal of Veterinary Research

Summary

Concurrent bacterial culturing of duodenal/proximal jejunal fluid and duodenal mucosa was performed on 2 occasions in each of 16 IgA-deficient German Shepherd Dogs with small intestinal bacterial overgrowth. The interval between sample collections in each dog was 74 to 78 days. Species of bacteria and numbers of bacterial colony-forming units (cfu) per milliliter of fluid were compared with species and numbers found in the concurrent duodenal mucosa sample. There was inconsistent correlation for number of cfu and minimal correlation for species of bacteria isolated from the 2 sites. Fewer bacterial cfu usually were isolated from the mucosa than from the concurrent fluid sample. When the same numeric criteria used for diagnosing small intestinal bacterial overgrowth in samples of intestinal fluid (ie, ≥ 105 bacterial or ≥ 104 anaerobic cfu/ml) were used to interpret results of culturing duodenal mucosa, quantitations of bacterial cfu in duodenal mucosa was found to be a specific, but insensitive test.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate chemotactic, phagocytic, and bactericidal activities of bovine and porcine alveolar macrophages (AM) exposed to tilmicosin.

Animals—12 healthy calves and 12 healthy pigs.

Procedure—Lungs were obtained immediately after euthanasia; AM were collected by means of bronchoalveolar lavage and density gradient centrifugation. Chemotactic activity was evaluated by exposing AM to lipopolysaccharide or macrophage inhibitory peptide during incubation with tilmicosin. Phagocytic activity was evaluated by incubating AM with tilmicosin for 24 hours and then with tilmicosin-resistant Salmonella serotype Typhimurium. Bactericidal activity was evaluated by incubating AM with tilmicosin (0, 10, or 20 µg/ml for bovine AM; 0 or 10 µg/ml or 10 µg/ml but washed free of tilmicosin for porcine AM) and then with Mannheimia haemolytica (bovine AM) or with Actinobacillus pleuropneumoniae or Pasteurella multocida(porcine AM).

Results—Tilmicosin had no significant effects on chemotactic or phagocytic activities of bovine or porcine AM. The time-course of bactericidal activity was best described by polynomial equations. Time to cessation of bacterial growth and area under the time versus bacterial number curve were significantly affected by incubation of AM with tilmicosin.

Conclusion and Clinical Relevance—Results show that bactericidal activity of bovine and porcine AM was enhanced by tilmicosin, but not in proportion to the reported ability of AM to concentrate tilmicosin intracellularly. With or without exposure to tilmicosin, the time-course of bactericidal activity of bovine AM against M haemolytica and of porcine AM against A pleuropneumoniae or P multocida was too complex to be reduced to a simple linear equation. (Am J Vet Res 2002;63:36–41)

Full access
in American Journal of Veterinary Research

Summary

Sixteen German Shepherd Dogs were found, via quantitative microbial culture of intestinal fluid samples, to have small intestinal bacterial overgrowth (ibo) over an 11-month period. All dogs were deficient in serum IgA. Consistent clinical signs suggestive of an alimentary tract disorder were not observed. Serum cobalamin determinations were not helpful in detecting ibo. Serum folate concentrations had variable sensitivity and specificity for detecting dogs from which we could culture ≥ 1 × 105 bacteria/ml from intestinal fluid samples in the nonfed state. Histologic and intestinal mucosal cytologic examinations were not useful in detecting ibo. Substantial within-dog and between-dog variation was found in the numbers and species of bacteria in the intestines. The difficulty in diagnosing ibo, the variability in organisms found in individual dogs on repeated sampling, the likelihood that intestinal fluid microbial cultures failed to diagnose ibo in some dogs, and the potential of ibo to be clinically inapparent were the most important findings in this study.

Free access
in Journal of the American Veterinary Medical Association