Characterization of spatiotemporal chaos in an inhomogeneous active medium

We study a reaction diffusion system of the activator-inhibitor type with inhomogeneous reaction terms showing spatiotemporal chaos. We analyze the topological properties of the unstable periodic orbits in the slow chaotic dynamics appearing, which can be embedded in three dimensions. We perform a bi-orthogonal decomposition analyzing the minimum number of modes necessary to find the same organization of unstable orbits.Comment: 13 pages, 6 figs. Physica D (in press

An outbreak of sheep-associated malignant catarrhal fever in sows

his paper describes a case of malignant catarrhal fever in a sow herd in Belgium caused by infection with ovine herpesvirus-2 (OHV-2). The 11 affected sows had high fever and 10 of them died within 3 days after the onset of clinical disease. The most prominent macroscopic lesion was a hemorrhagic to pseudo-membranous gastritis. Histopathology revealed severe infiltration and necrosis of the gastric mucosa. Neither antimicrobial treatment nor injection with anti-inflammatory drugs ameliorated the severity of the disease. As the sows and sheep were housed in the same building with the possibility of having direct nose-to-nose contact, and as PCR testing showed that the virus found in the sows was identical to that found in the sheep, it is very likely that the infection was transmitted from the subclinically infected sheep to the sows. The present case showed that OHV-2 infection should be included in the differential diagnosis when facing problems of fever followed by death, especially when pigs are housed in close contact with sheep

Detection of hepatitis e virus (HEV) antibiodies in swine herds in Québec, Canada

Hepatitis E virus (HEV) has a zoonotic potential and pork products have been identified as possible human infection sources. Swine HEV infection in pigs have now been reported in pigs in many countries and generally occurs at about 2-3 months of age. Data from USA indicated that about 80-100% of pigs in commercial farms are infected. The objective of this study was to estimate prevalence of HEV in selected Canadian herds by serology using the PrioCHECK HEV Ab porcine-ELISA kit

Assessment of the efficiency of ozonated water as bacterial contamination reduction tool in a pork cutting plant

The food industry is constantly searching for new tools to reduce bacterial contamination in the plants. In this study we assessed the efficiency of ozonated water as a tool to improve reduction of residual bacterial contamination in a pork cutting plant as a complement of sanitation procedures. First, the effectiveness of the ozonated water was tested on conveyors to reduce residual Salmonella, coliforms and aerobic flora load

Evaluation of ozonated water as a microbiological risk mitigation option in pork production

Ozone is an oxidative moleculewith a bactericidal effect. This molecule can be solubilized in water and was proposed as an alternative disinfecting solution to be used in food production plants. Ozone molecule possesses many industrially relevant characteristics, such as the absence of residues following its application, usability at meat industries’ room temperature, and applicability during production activities. The objective of this study was to evaluate the benefits of an ozonated water rinse on the wrapping of meat logs at the entrance of a slicing plant

Prevalence of Salmonella spp in finishing swine in Canada

Meat and meat products play a major role in the transmission of some zoonotic diseases. Carriers animals are an important component in the epidemiology of Salmonella. These animals shed Salmonella and may contribute to contaminate environment, instruments and eventually meat in abattoirs. Given the failure of post-harvest measures to control these pathogens, efforts are now being made to control microbial pathogens at the farm-level. Nevertheless, evaluating farm-level control options requires knowledge of basic data such as prevalence and distribution of pathogens in animals and herds. This study was conducted to evaluate the prevalence of Salmonella spp. in finishing swine at slaugtherhouses in Canada and to evaluate the distribution of this pathogen among different herds

Residual contamination detection and serovar distribution of Listeria monocytogenes isolates in pork slaughterhouse and cutting facilities in province of Quebec

L. monocytogenes (L. mono) is recognised as a zoonotic foodborne pathogen. Its control is focused on the “Readyto Eat” food production level. Recently, Health Canada had reinforced its “Policy on L. mono in Ready-to-Eat Foods”, highlighting environmental surveillance and control of meat processing facilities as important risk reduction tools. The industry wants to improve its management of L. mono risk, taking into account previous steps of meat production. Nowadays, few information are available on the presence, distribution and types of strains in the environments concerning this pathogen in pork slaughterhouses and cutting facilities in Canada. Our objective was to detect and described residual L. mono contamination and analyse serovars distribution in different areas in the pork production continuum in and between slaughterhouses and cutting facilities in province of Quebec, during a one year period. Such data are a pre-requisite to achieve the optimization of the management measures by the industrials

Control of salmonella in swine by use of probiotics

Control of Salmonella on the farm is currently undertaken by changes in management protocols or by use of live attenuated vaccines (Roof et al., 1992; Kramer et al., 1992). Although these vaccines are efficacious in reducing morbidity and mortality associated with salmonellosis, carrier animals are still evident within the population. While the carrier state has been defined for S. typhimurium and S. choleraesuis under experimental conditions (Wood et al., 1989; Fedorka-Cray et al., 1994; Gray et al., 1995, 1996a, 1996b), little is known about the exact modes of transmission and maintenance of the disease in swine herds

Data on distribution and characterization of Listeria monocytogenes strains in a pork slaughter and cutting plant in Quebec support an earlier surveillance in the meat production chain

Listeria monocytogenes is a major public health concern. It has been associated with highly mediatised outbreaks. It was the case in 2008, when an important episode (23 deaths) in Canada showed the need to reinforce the policies to better control Listeria in ready-to-eat products. Improved surveillance in the production plants environment increased the detection levels and represents a challenge for both industries and control agencies