Characterization of Salmonella Isolates Recovered from Stages of the Processing Lines at Four Broiler Processing Plants in Trinidad and Tobago

Abstract

This cross-sectional study determined the prevalence, characteristics, and risk factors for contamination of chicken with Salmonella at four operating broiler processing plants in Trinidad. Standard methods were used to isolate and characterize the Salmonella isolates. The overall prevalence of Salmonella at the four processing plants was 27.0% (107/396). The whole carcass enrichment (WCE) method yielded a statistically significantly (p = 0.0014) higher frequency of isolation (53.9%; 97/180) than the whole carcass rinse (35.0%; 63/180) and neck skin methods (42.2%; 38/90). S. enterica serotypes Enteritidis, Javiana, and Infantis were the predominant serotypes isolated accounting for 20.8%, 16.7% and 12.5%, respectively, of the serotyped isolates. Risk factors included the use of over 100 contract farmers (OR 4.4), pre-chiller (OR 2.3), addition of chlorine to chiller (OR 3.2), slaughtering sick broilers (OR 4.4), and flocks with >50% mortality. Multi-drug resistance was detected in 12.3% (14/114) of the isolates of Salmonella. Resistance was high to kanamycin (85.7%) and doxycycline (74.6%) but low to amoxicillin-clavulanic acid (2.4%) and sulphamethoxazole-trimethoprim (0.8%). The occurrence of resistant Salmonella in chickens processed at commercial broiler processing plants has implications for salmonellosis and therapeutic failure in consumers of improperly cooked contaminated chickens from these plants in the country.

Genetic Characterization of Salmonella Infantis with Multiple Drug Resistance Profiles Isolated from a Poultry-Farm in Chile

“…In this study, we found genotypic and phenotypic evidence that this occurs in strains isolated from poultry meat. This phenomenon has been widely reported before, in Chile and in other countries [92][93][94][95][96]. The strains we isolated are resistant to commonly used antibiotics such as tetracycline, aminoglycoside, and beta-lactam.…”

Salmonella in Pig Farms and on Pig Meat in Suriname

“…We could not find a single study on antimicrobial resistance genes in Salmonella from pigs in the Caribbean, and only few on Salmonella as a whole in the Caribbean. In poultry strains in Trinidad, a quite higher prevalence of resistance was found compared to our study, and this included plasmid-mediated colistin resistance [36][37][38].…”

Molecular Characterization of Salmonella Detected along the Broiler Production Chain in Trinidad and Tobago

“…Whole-genome sequencing analysis has been used to investigate genetic characteristics and phylogenies among Salmonella strains isolated from different origins, such as humans, food, animals, and the environment [ 33 , 34 , 35 , 36 ]. The current study was comprised of isolates from four cross-sectional studies conducted at the level of retail outlets (2016–2017) [ 25 ], broiler processing plants (2018) [ 23 ], broiler farms, and broiler hatcheries (2019) [ 22 ]. Although several limitations exist with the use of cross-sectional instead of longitudinal studies, this approach provides valuable information on the status of Salmonella shedding and contamination at the four levels (hatcheries, farms, processing plants, and retail outlets) of the broiler production chain in the country.…”

“…A total of 146 isolates of Salmonella used in this study originated from prior studies conducted at hatcheries and broiler farms [ 22 ], broiler processing plants [ 23 ], and retail outlets (pluck shops and supermarkets) [ 24 , 25 ]. The type of samples collected from the various studies are as follows, hatcheries: broken eggshells, eggs in the hatcher, eggs in the incubator, hatcher environmental swabs, hatcher fluff, and stillborn chicks; broiler farms: boot swabs, cloacal swabs, litter drag swabs, feed, and water samples—in-house supply and storage tank; processing plants: chilled chicken parts, chilled whole carcasses, neck skins, pre-evisceration carcasses, and post-evisceration carcasses; retail outlets: chicken carcasses.…”

“…Conventional serotyping methods using the phase reversal technique described previously [ 22 , 23 , 25 ] were performed at the Public Health Laboratory, Ministry of Health, St. Michael, Barbados. Antimicrobial resistance determined by the disk diffusion method [ 22 , 23 , 24 ] described previously was also used. Data generated from these two methods were compared to the genomic data.…”