A new molecular approach to assess the occurrence of Sarcocystis spp. in cattle and products thereof: preliminary data

The genus Sarcocystis consists of more than 200 species. Those protozoa are characterised by a biological cycle composed by two obligatory hosts, definitive and intermediate. Apart from being possibly pathogenic for the intermediate host, a number of authors consider the intestinal sarcocystosis a minor zoonotic disease. Humans, in fact, can act as definitive host for two sarcosporidian species, S. suihominis e S. hominis, being infected through the consumption of raw or undercooked pig and bovine meat, respectively. Other two species could parasitise cattle: S. cruzi and S. hirsuta, having canids and felids as definitive hosts, respectively. The three species differentiate from each other in dimensions and cystic wall morphology, this latter being the basis for taxonomical studies. In 2010, the European Food Safety Authority (EFSA) highlighted the absence of reliable methods for epidemiological studies on the presence of Sarcocystis spp. in animals and products thereof. On this basis, the present study has been developed a new molecular method for the identification of Sarcocystis in bovine meat. For the development of the polymerase chain reaction (PCR) protocol, a set of samples of bovine meat from cattle (N=15), slaughtered at the didactic abattoir at the Veterinary Faculty of Turin University, has been collected, sequenced and used as reference samples during the study. A second set of samples (N=29), gathered from the same abattoir (N=12) and from abattoirs of Piedmont region (N=17), has been used for applicability tests. The overall positive rate for Sarcocystis spp. in our samples has been 91% (40/44), with S. cruzi representing the species with higher rates (68%), followed by S. hominis (43%) and S. hirsuta (2%). Based on the results of specificity and applicability tests performed in this study, the newly developed protocol proved to be reliable and suitable for epidemiologic purposes

Effect of gaseous ozone treatment on biofilm of dairy-isolated Pseudomonas spp. strains

Microbial biofilms existing in food industries have been implicated as important contamination sources of spoilage and pathogenic microorganisms in the finished products. Among the innovative strategies proposed to contrast biofilms in food environments, ozone is recognised as an environmentally friendly technology but there are few studies about its effect against bacterial biofilms. The objective of this study was to evaluate the effect of gaseous ozone (50 ppm for 6 h) in inhibition and eradication of biofilm formed by twenty-one dairyisolated Pseudomonas spp. strains. Before ozone treatments, all isolates were screened for biofilm formation according to a previously described method. Strains were then divided in four groups: weak, weak/moderate, moderate/strong, and strong biofilm producers based on the biofilm biomass value of each isolate determined using the optical density (OD - 595 nm). Inhibition treatment was effective on the strain (C1) belonging to the weak producers’ group, on all strains classified as weak/moderate producers, on two strains (C8 and C12) belonging to the group of moderate/strong producers and on one strain (C13) classified as strong producer. Conversely, eradication treatments were ineffective on all strains tested, except for the strain C4 which reduced its biofilm-forming abilities after exposure to ozone gas. In conclusion, gaseous ozone may be used to enhance existing sanitation protocols in food processing environments, but its application alone not seems sufficient to contrast Pseudomonas spp. established biofilms