This study determined whether multilocus sequence types (MLST) ofCampylobacterfrom poultry in 2 farms in Grenada, West Indies, differed by farm, antimicrobial resistance and farm antibiotic use. Farm A used fluoroquinolones in the water and Farm B used tetracyclines. The E-test was used to determine resistance of isolates to seven antibiotics. PCR of theIpxAgene confirmed species and MLST was used to characterize 38 isolates. All isolates were eitherC. jejuniorC. coli. Farm antibiotic use directly correlated with antimicrobial resistance ofCampylobacterisolates. Almost 80% of the isolates from Farm A were fluoroquinolone resistant and 17.9% of the isolates from Farm B were fluoroquinolone resistant. AllCampylobacterisolates from Farm A were tetracycline sensitive, whereas 35.7% of isolates from Farm B were tetracycline resistant. Six previously recognized sequence types (STs) and 2 novel STs were identified. Previously recognized STs were those overwhelmingly reported from poultry and humans globally. Isolates with the same ST did not always have the same antibiotic resistance profile. There was little ST overlap between the farms suggesting that within-farm transmission ofCampylobactergenotypes may dominate. MLST typing was useful for trackingCampylobacterspp. among poultry units and can help elucidateCampylobacterhost-species population structure and its relevance to human health.

Rectal swabs from 155 sheep and 252 goats from Grenada were evaluated to determine the prevalence ofCampylobacterspp., antibiotic resistance, and multilocus sequence types. FifteenCampylobacterisolates were obtained (14C. jejuniand 1C. coli). The prevalence (3.7%) did not differ significantly between sheep (4.5%) and goats (3.2%). Among the seven antimicrobials tested, resistance was only detected for tetracycline (30.8%) and metronidazole (38.5%).Campylobacterisolates showed no significant difference between sheep and goats for type of antimicrobial resistance or percent of resistant isolates. Twelve of the isolates were successfully genotyped consisting of four recognized clonal complexes and three novel sequence types. Importantly, one isolate from one goat was identified as theC. jejunisequence type-8, a zoonotic and tetracycline-resistant clone reported to be a highly virulent clone associated with ovine abortion in the USA. Although most samples were from comingled sheep and goat production units, there were no shared sequence types between these two host species. None of the sequence types identified in this study have previously been reported in poultry in Grenada, suggesting sheep- and goat-specificCampylobacterclones in Grenada. This is the first report of genotyping ofCampylobacterisolates from sheep and goats in the Eastern Caribbean.

Infections with tick-borne pathogens belonging to Anaplasma/Ehrlichia in various vertebrate hosts are a persistent problem resulting in nonspecific clinical signs during early infection. Diagnosis of single and multi-infections with these pathogens, causing diseases in companion/agricultural animals and people, remains a challenge. Traditional methods of diagnosis, such as microscopy and serology, have low sensitivity and specificity. Polymerase chain reaction (PCR) assays are widely used to detect early-phase infections, since these have high sensitivity and specificity. We report the development and validation of an assay involving PCR followed by magnetic capture method using species-specific oligonucleotides to detect six Anaplasma/Ehrlichia species pathogens in canine, bovine, caprine, and ovine blood samples. Overall, the assay application to 455 samples detected 30.1% (137/455) positives for one or more out of six screened pathogens. Single-pathogen infections were observed in 94.9% (130/137) of the positive samples, while co-infections were detected in 5.1% (7/137). Anaplasma marginale infection in cattle had the highest detection rate (34.4%), followed by canines positive for Anaplasma platys (16.4%) and Ehrlichia canis (13.9%). The assay aided in documenting the first molecular evidence for A. marginale in cattle and small ruminants and Ehrlichia chaffeensis and Ehrlichia ewingii in dogs in the Caribbean island of Grenada.