Short communication. Isolation of Aeromonas hydrophila in piglets

Abstract

The production of Alentejano breed pig started a recovery two decades ago due to increasing demand for gourmet products. These pigs are raised in rotational semi-extensive or extensive outdoor production systems in the "Montado" (green and cork oak forest), grazing and feeding acorns and other associated food resources. Bacteria of the genus Aeromonas are considered as emerging pathogens of importance for man and animals, but its involvement in swine is not well documented. In the context of a study made at the University of Évora to assess the specific diseases of Alentejano swine, diseased piglets from two farms were submitted for pathological and bacteriological examinations. Pathological examinations revealed changes characteristic of septicemia, and Aeromonas hydrophila was isolated in pure culture from multiple organs of piglets from both farms. Antibiotic sensitivity tests showed that the isolates from one of the farms were susceptible to gentamicin, oxitetracycline, neomycin, enrofloxacin, colistin sulfate, trimethoprim, ceftiofur, and amoxicillin plus clavulanic acid. In contrast, the A. hydrophila isolated in the other farm was resistant to all drugs tested but enrofloxacin. This is the first report in the world showing the relationship between septicemia and A. hydrophila infection in piglets. The importance of this finding is further reinforced by the fact that these bacteria can be highly resistant to antimicrobial agents.Additional key words: Alentejano swine breed; Iberian swine; emerging pathogens; resistance to antibiotics. Resumen Comunicación corta. Aislamiento de Aeromonas hydrophila en lechonesLa producción tradicional de cerdo de raza Alentejana se ha recuperado en los últimos años debido a la creciente demanda de productos tipo gourmet. Estos cerdos son criados en sistemas extensivos o semi-extensivos en la dehesa arbolada, en los que la ingestión de bellotas (Montanera) se complementa con otras fuentes de alimentación. Las bacterias del género Aeromonas son consideradas como patógenos emergentes de importancia para el hombre y los animales, pero su repercusión en ganado porcino es prácticamente desconocida. En un estudio realizado en la Universidad de Évora para determinar las enfermedades de los cerdos de esta raza, se realizó un examen anatomopatológico postmortem de lechones de dos granjas, se tomaron muestras de diversos órganos durante la necropsia y se examinaron bacteriológicamente. El examen patológico puso en evidencia lesiones típicas de septicemia en las dos granjas y de varios órganos se aisló Aeromonas hydrophila en cultivo puro. Las cepas aisladas en una de las granjas se mostraron sensibles, mediante un antibiograma, a gentamicina, oxitetraciclina, neomicina, enrofloxacina, sulfato de colistina, trimetoprim, ceftiofur y amoxicilina más ácido clavulánico. Sin embargo, las cepas aisladas en la otra granja fueron resistentes a todos los antibióticos estudiados con la excepción de la enrofloxacina. Esta constituye la primera cita de aislamiento de A. hydrophila en lecho...

Isolation and antimicrobial testing of Aeromonas spp., Citrobacter spp., Cronobacter spp., Enterobacter spp., Escherichia spp., Klebsiella spp., and Trabulsiella spp. from the gallbladder of pigs

“…However, it is more often isolated from food of plant and animal origin than animal disease (Queiroga et al, 2012). A. hydrophila is producing haemolysins, enterotoxin (Ljungh et al, 1981) and is multidrug resistant (Queiroga et al, 2012), as it was observed here. Its isolation from pig gallbladders and its resistance to most of the antibiotics tested here, support its classification as an emerging pathogen for animals and man.…”

“…hydrophila, incriminated in a variety of human clinical conditions, such as gastroenteritis, septicemia, cellulitis, myonecrosis, peritonitis, hepatitis, pancreatic abscesses, respiratory, urogenital and eye infections of immunocompromised individuals, is also implicated in infections of poikilothermic animals (amphibians, reptiles and fish) (Janda and Abbott, 2010). However, it is more often isolated from food of plant and animal origin than animal disease (Queiroga et al, 2012). A. hydrophila is producing haemolysins, enterotoxin (Ljungh et al, 1981) and is multidrug resistant (Queiroga et al, 2012), as it was observed here.…”

Antibacterial potential and mechanism of action of dithiocyano‐methane as a bactericidal agent for farm disinfection

“…Aeromonas hydrophila, a known zoonotic pathogen living mainly in water (Krovacek et al 1993;Rahimi-Larki and Nene 2006), has been associated with diseases in several fulminant fish and livestock (Pathiratne et al 1994;Rahimi-Larki and Nene 2006;Awaad et al 2011;Queiroga et al 2012), and caused severe losses in the aquaculture industry and animal husbandry. At present, antibiotics are the primary way to kill Aer.…”

Food Safety: Emerging Pathogens

“…They are also found in raw sewage, sewage effluents, and sewage-contaminated waters and activated sludge (Dumontet et al, 2001;Igbinosa et al, 2012). Aeromonads have long been considered as opportunistic pathogens of both aquatic (warmand cold-water fish) and terrestrial animals (Harikrishnan and Balasundaram, 2005;Isonhood and Drake, 2002;Queiroga et al, 2012). Nonetheless, the motile mesophilic aeromonads, and particularly Ae.…”

“…Another issue of major importance for the public health significance of Aeromonas spp. is the increasing documentation of isolates exhibiting resistance to several antimicrobial agents (Queiroga et al, 2012). Hence, in the context of basic control procedures common for all foodborne pathogens (i.e., prevention of contamination, reduction of contamination, and prevention of microbial growth), the aforementioned issues need to be particularly addressed with regard to aeromonads.…”