ABSTRACT
Ammonium quaternary compounds are widely used in poultry and swine production as disinfectants in the control of pathogens. They act on gram-positive bacteria, gram-negative bacteria, enveloped fungi and viruses. However, in some conditions of pH and presence of organic matter can be inactivated. This study evaluated the action of ammonium quaternary compounds at 1:1,000 and 1:2,000 dilutions against Salmonella enterica serovarTyphimurium and Salmonella enterica serovar Enteritidis in the presence of three different organic matter simulators, fetal bovine serum, skim milk and whole milk concentration of 1, 3, 5, and 7% and at pH 6 and 9, with 15 min of contact. It was possible to verify that the organic matter simulators adjusted in the same conditions of contact time and percentage, in the in vitro tests, presented different results and the fetal bovine serum did not inactivate the disinfectant. However, the best result against S. Typhimurium and S. Enteritidis was obtained at pH 6 at the dilution of 1:1,000 in all organic matter simulators.
Subject(s)
Salmonella enteritidis , Containment of Biohazards , Salmonella enterica , Organic Matter , Quaternary Ammonium Compounds , Swine , Birds , In Vitro Techniques , Serum Albumin, Bovine , Milk , Disinfectants , Gram-Negative Bacteria , Gram-Positive BacteriaABSTRACT
Clostridium perfringens is an anaerobic Gram-positive bacterium known as common pathogen for humans, for domestic and wildlife animals. Although infections caused by C. perfringens type C and A in swine are well studied, just a few reports describe the genetic relationship among strains in the epidemiological chain of swine clostridioses, as well as the presence of the microorganism in the slaughterhouses. The aim of the present study was to isolate C. perfringens from feces and carcasses from swine slaughterhouses, characterize the strains in relation to the presence of enterotoxin, alpha, beta, epsilon, iota and beta-2 toxins genes, using polymerase chain reaction (PCR) and comparing strains by means of Pulsed field gel electrophoresis (PFGE). Clostridium perfringens isolation frequencies in carcasses and finishing pig intestines were of 58.8% in both types of samples. According to the polymerase chain reaction assay, only alfa toxin was detected, being all isolates also negative to enterotoxin and beta2 toxin. Through PFGE technique, the strains were characterized in 35 pulsotypes. In only one pulsotype, the isolate from carcass sample was grouped with fecal isolate of the same animal, suggesting that the risk of cross-contamination was low. Despite the high prevalence of C. perfringens in swine carcasses from the slaughterhouses assessed, the risk of food poisoning to Brazilian pork consumers is low, since all strains were negative to cpe-gene, codifying enterotoxin.
Clostridium perfringens é uma bactéria Gram positiva anaeróbica, conhecida por infectar os seres humanos, animais domésticos e de vida selvagem. Apesar de as infecções causadas por C. perfringens tipo C e A em suínos serem bastante estudadas, poucos relatos descrevem a relação genética entre as linhagens envolvidas na cadeia epidemiológica da clostridiose suína, bem como a presença do microorganismo em abatedouros. O objetivo do presente estudo foi isolar C. perfringens a partir das fezes e carcaças de suínos no abatedouro, caracterizar os isolados quanto à presença dos genes codificadores de enterotoxina, toxina alfa, beta, épsilon, iota e beta 2 através da PCR e comparar os isolados através da eletroforese em campo pulsado (PFGE). A frequência de isolamento do agente em carcaças e em intestinos de suínos foi de 58,8% para ambos os tipos de amostras. De acordo com a reação em cadeia pela polimerase, somente a toxina alfa foi detectada, sendo todos os isolados negativos para toxina beta2 e enterotoxina. Através da técnica de PFGE, as cepas foram caracterizadas em 35 pulsotipos, sendo que, em apenas um caso, um isolado de amostras de carcaças foi agrupado no mesmo pulsotipo do isolado de fezes do mesmo animal, indicando que a possibilidade de contaminação cruzada no processamento da carcaça foi baixa. Apesar da alta prevalência de C. perfringens em carcaças de suínos provenientes dos abatedouros avaliados, o risco de intoxicação alimentar para os consumidores de carne suína brasileira é baixo, já que todas as cepas foram negativas para o gene cpe, codificador de enterotoxina.