Short communication: Determination of Salmonella clustered regularly interspaced short palindromic repeats (CRISPR) diversity on dairy farms in Wisconsin and Minnesota

摘要: Salmonella enterica ssp. is a foodborne pathogen able to cause disease in both humans and animals. Diverse serovars of this exist, some which are host specific, causing range clinical symptoms from asymptomatic infection through morbidity mortality. According 2007 survey by the USDA National Animal Health Monitoring System, fecal shedding healthy cows occurs on 39.7% dairy farms United States. Certain frequently isolated majority isolates System study were represented 5 serovars; however, genotypic diversity was not examined. The objective determine clustered regularly interspaced short palindromic repeats (CRISPR) loci collected 8 with previous history salmonellosis. None or calves sampled 2 Salmonella, although detected cow bedding sample 1 these farms. populations discrete each farm, according CRISPR typing, exception an Anatum var. 15+ type 6 Montevideo 2. One 4 distinct genotypes identified per farm. typing differed within serovars, as Montevideo, 15+, Muenster had no overlap spacer content, even same reflecting between- within-serovar genetic diversity. dynamic nature shown farm that longitudinally over 13.5 mo. Changes serovar 3,19:-:z27 observed between first sampling time mo later, concomitant change alleles. results indicate strains present smaller herds (<500 head) specific new may emerge time.