Search Results

You are looking at 1 - 2 of 2 items for

  • Author or Editor: Scott Ladely x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To evaluate the antimicrobial susceptibility patterns of Salmonella isolates from feedlot cattle.

Design—Cross-sectional study.

Sample Population—263 Salmonella isolates.

Procedures—Fecal samples were collected from the floor of 2 pens in each of 100 feedlots. Two hundred eighty Salmonella isolates were recovered after bacteriologic culture from 38 pens. Of these, 263 isolates were available for antimicrobial susceptibility testing to 16 antimicrobials, using microbroth dilution breakpoint plates.

Results—Less than 5% of isolates were resistant to any of the antimicrobials tested, with the exception of sulfamethoxazole (15; 5.7%) and tetracycline (61; 23.2%). Most isolates (197; 74.9%) were susceptible to all antimicrobials tested, whereas 18 (6.8%) were resistant to 2 or more antimicrobials. The percentage of isolates with resistance to any antimicrobial varied by serotype. The percentage of isolates resistant to various antimicrobials was not related to concurrent use of antimicrobials in the feed.

Conclusions and Clinical Relevance—With the exception of tetracycline and sulfamethoxazole, resistance of Salmonella isolates to any of the antimicrobials was uncommon. Most isolates were susceptible to all antimicrobials tested. Antimicrobial resistance was not related to the presence of antimicrobials in the ration being fed at the time of sample collection. (J Am Vet Med Assoc 2002;221:268–272)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To estimate prevalence of fecal shedding of Salmonella spp among horses in the US horse population and prevalence of Salmonella spp in grain or other concentrate used as horse feed on equine operations in the United States.

Design—Cross-sectional survey.

Sample Population—Horses on 972 operations in 28 states.

Procedure—Fecal samples were collected from horses resident at each operation. Only a single sample was collected from any individual horse; number of horses from which samples were collected on each operation was determined on the basis of number of horses on the operation. A single sample of grain or concentrate was also collected from each operation. All samples were tested for Salmonella spp by means of bacterial culture.

Results—Overall, 0.8% (SE, 0.5) of resident horses shed Salmonella spp in their feces. The overall prevalence of operations positive for fecal shedding of Salmonella spp (ie, operations with ≥ 1 horse shedding Salmonella spp in its feces) was 1.8% (SE, 0.7). Prevalence of grain or other concentrate samples positive for Salmonella spp was 0.4%. Serotypes of Salmonella spp that were identified in grain or other concentrate were not those typically associated with clinical disease in horses.

Conclusions and Clinical Relevance—Results suggest that the national prevalence of fecal shedding of Salmonella spp by horses in the United States was 0.8%, and that prevalence of Salmonella spp in grain or other concentrate used for horse feed was 0.4%.(J Am Vet Med Assoc 2000;217:226–230)

Full access
in Journal of the American Veterinary Medical Association