Prevalence, distribution, and molecular characterization of Salmonella recovered from swine finishing herds and a slaughter facility in Santa Catarina, Brazil

Abstract

Swine can carry Salmonella strains that may be transmitted to humans by pork products. This investigation determined the distribution and types of Salmonella in 12 swine finishing herds and a slaughter facility in Santa Catarina, Brazil. A total of 1258 samples, consisting of environmental, feed, carcass, lymph node, and fecal material were collected and submitted to bacteriological isolation of Salmonella. From 487 positive samples, 1255 isolates were recovered and confirmed to be Salmonella. The distribution of positive samples was as follows: finishing pen floors 26% (16/61); feed 29% (42/143); feces 44% (52/119); pooled feces 59% (35/59); slaughter holding pens 90% (36/40); lymph nodes 46% (220/478); pre-chilled carcass surfaces 24% (24/98); and post-chilled carcass surfaces 24% (62/260). The most prevalent serovars were Typhimurium, Panama, Senftenberg, Derby, and Mbandaka. By pulsed-field gel electrophoresis, 1071 isolates were subtyped using XbaI, and duplicate isolates were removed. From the remaining 747 isolates, 163 macrorestriction profiles (pulsotypes) were identified. Six pulsotypes were considered very frequent, occurring in 33 isolates or more. The multiple correspondence analyses showed correlations between pulsotypes from shedding pigs (feces), herd environment (pen floors), and subiliac and prescapular lymph nodes and between lairage and carcass surface samples before and after chilling. All sources of Salmonella investigated contributed to the carrier state; however, pre-slaughter contamination at lairage was the variable most strongly associated with carcass contamination. A total of 59 different antimicrobial resistance profiles were observed in 572 Salmonella isolates. From these isolates, 17% (97/572) were susceptible to all 15 antibiotics tested, 83% (475/572) were resistant to at least one, and 43% (246/572) were resistant to four or more antibiotics (multi-resistant). The AmpGenKanTet profile was the most prevalent in carcass isolates and was associated with farm origin.

Principais ameaças sanitárias endêmicas da cadeia produtiva de suínos no Brasil

“…A Salmonella choleraesuis é a principal sorovar capaz de causar doença clínica em suínos, sendo rara nos rebanhos tecnificados do Brasil (Kich et al, 2011). Entretanto, os suínos podem se infectar com uma variedade de sorovar que não cause a doença clínica, mas que pode ser importante fonte de contaminação para os produtos finais.…”

“…Entretanto, os suínos podem se infectar com uma variedade de sorovar que não cause a doença clínica, mas que pode ser importante fonte de contaminação para os produtos finais. A prevalência destas sorovares nos suínos de abate é elevada, e as mais frequentes são Typhimurium, Panamá, Senftenberg, Derby e Mbandaka (Kich et al, 2011). Como a Salmonella Typhimurium é a segunda mais importante nas infecções alimentares em humanos, deve-se enfatizar a necessidade e a importância de implementar programas de controle que englobem desde as unidades produtoras e o transporte, até o abate e o interior dos abatedouros (Lima et al, 2016).…”

Genotypic diversity, pathogenic potential and the resistance profile of Salmonella Typhimurium strains isolated from humans and food from 1983 to 2013 in Brazil

“…In Brazil, some studies have demonstrated an increase of multidrug-resistant (MDR) S. Typhimurium strains Bessa et al, 2007;Fernandes et al, 2009;Kich et al, 2011).…”

“…Despite its clinical importance, there are few studies that have molecularly characterized S. Typhimurium strains in Brazil and assessed their antimicrobial resistance profile Bessa et al, 2007;Tavechio et al, 2009;Kich et al, 2011). Therefore, the aims of this study were to assess the presence of some virulence markers and to evaluate the antimicrobial resistance patterns and the genotypic diversity using PFGE, MLVA and ERIC-PCR of S. Typhimurium strains isolated from humans and food sources between 1983 and 2013 in Brazil to better understand their pathogenic potential, resistance profile, epidemiology and genotypic diversity.…”

Acid and low temperature treatments on Salmonella Enteritidis inoculated in pork and its subsequent survival in simulated gastric fluid

“…Several reports documented the presence of S. Enteritidis in swine abattoirs in Brazil (BESSA et al, 2004;KICH et al, 2011). Strategies used in abattoirs to prevent S. enterica growth include lower storage temperatures and surface decontamination using acids (SUN et al, 2003;PIPEK et al, 2006).…”