Prevalence and molecular characterization ofSalmonella entericaisolates throughout an integrated broiler supply chain in China

Abstract

A total of 1145 samples were collected from chicken breeder farms, hatcheries, broiler farms, a slaughterhouse and retail refrigerated chicken stores in an integrated broiler supply chain in Guangdong Province, China, in 2013. One-hundred and two Salmonella enterica strains were isolated and subjected to serotyping, antimicrobial susceptibility testing, virulence profile determination and molecular subtyping by pulsed field gel electrophoresis (PFGE). The contamination rates in samples from breeder farms, hatcheries, broiler farms, the slaughterhouse and retail stores were 1·46%, 4·31%, 7·00%, 62·86% and 54·67%, respectively. The isolated strains of S. enterica belonged to 10 serotypes; most of them were S. Weltevreden (46·08%, 47/102) and S. Agona (18·63%, 19/102). Isolates were frequently resistant to streptomycin (38·2%), tetracycline (36·3%), sulfisoxazole (35·3%) and gentamicin (34·3%); 31·4% of isolates were multidrug resistant. The isolates were screened for 10 virulence factors. The Salmonella pathogenicity island genes avrA, ssaQ, mgtC, siiD, and sopB and the fimbrial gene bcfC were present in 100% of the strains. PFGE genotyping of the 102 S. enterica isolates yielded 24 PFGE types at an 85% similarity threshold. The PFGE patterns show that the genotypes of S. enterica in the production chain are very diverse, but some strains have 100% similarity in different parts of the production chain, which indicates that some S. enterica persist throughout the broiler supply chain.

Prevalence of Salmonella Isolates and Their Distribution Based on Whole-Genome Sequence in a Chicken Slaughterhouse in Jiangsu, China

“…Seven S. Corvallis isolates were isolated in the first visit, in which the serotype was also reported in chicken from Brazil with an isolation rate of 7.9% (29). In the present study, the prevalence of S. Kentucky and S. Enteritidis in the slaughterhouse was 44.7 and 32.5%, which was consistent with findings reported in Guangdong province (27,28). However, the results were quite different from the results in Sichuan province, in which S. Derby and S. Typhimurium were identified as the most common serotypes (26).…”

“…In China, the isolation rate of Salmonella was 12.7% in chickens in Shandong province (13), while no Salmonella was detected in a chicken slaughterhouse in Sichuan province (26). However, in Guangdong province, the prevalence of Salmonella in chicken and pork meat at retail markets was 63.6 and 73.1%, respectively, and 62.86% of samples from slaughterhouse were detected to be positive for Salmonella (27,28). In Jiangsu province, the prevalence of Salmonella in pig slaughterhouses and retail markets was 71.8 and 70.9%, respectively (20).…”

Tracing of Salmonella Contaminations Throughout an Integrated Broiler Production Chain in Dakahlia Governorate, Egypt

“…In this respect, nearly similar incidences of surface contamination for salmonella were reported by several researchers (Adzitey et al, 2012;Wang et al, 2013) in poultry processing environment with a rate of 23.5 and 25%, respectively. On the other side, high positive percentage rate (62.9%, 22/35) was also reported in china slaughter house samples (Ren et al, 2016). However, diverse surveys are still reported from several developing countries.…”

“…In China, 54·67% of the 75 retail store raw chicken samples was contaminated with Salmonella spp. (Ren et al, 2016). Nevertheless, a comparatively low isolation rate (1.56%) was reported from Morocco in poultry processing plan (Cohen et al, 2007).…”

“…These findings went in parallel with that reported by Abd-Elghany et al (2015) who stated that S. Typhimurium and S. Enteritidis were considered the most predominant serotypes present in Egyptian poultry farms. On the other side, low frequency of salmonella infection was reported in broilers chicken flocks in several studies (Ibrahim et al, 2013;El-Tawab et al, 2015;Ren et al, 2016;Elmonir et al, 2017;Elkenany et al, 2018) corresponded to 16.6, 12.4, 7, 20 and 13.5%, respectively. In an interesting study (Pieskus et al, 2008), the occurrence of salmonella infection in conventional broiler stocks located in different areas in Italy, Germany, Lithuania and the Netherlands were 20%, 0, 29 and 11%, respectively.…”