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The objective of this study was to carry out a quantitative risk assessment (QRA) of Mycobacterium avium subsp. paratuberculosis (MAP) survival in pasteurized milk produced by industrial dairy plants. Data were collected in three dairy plants (A, B and C) located in three different Italian regions and processing 38.75 (plant A), 89.29 (plant B) and 190.56 million litres (Plant C) of milk yearly. Plants A and plant C produce pasteurized milk, soft and hard industrial cheeses and yogurt; plant B produces only pasteurized milk. In-line milk filter (ILMF) samples and/or bulk milk samples were collected from all 569 herds delivering milk to the three dairy plants. Samples were analyzed by quantitative real-time PCR (qPCR). The QRA considered the presence of MAP in ILMF and in bulk milk of all the dairy herds delivering milk to the three investigated dairy plants, estimating MAP concentration in raw milk on the basis of these data, the dilution effect due to mixing milk in collecting trucks and in plant silos, and the effect of pasteurization in reducing the MAP load. The expected fraction of litres of pasteurized milk with 0 MAP would be 99.02%, 99.45% and 99.12%, in plants A, B and C respectively, and an overall percentage 0.55 % to 0.98% of pasteurized milk having a MAP contamination > 0 colony forming units (CFU)/l and 0.04% – 0.11% of pasteurized litres with a MAP contamination > 100 CFU/l was predicted. A daily variation was observed in the proportion of MAP-contaminated litres of milk. The study demonstrated that milk in the dairy plants investigated may be a source of MAP exposure for humans. The between-herd and within-herd MAP apparent prevalence in the investigated areas are likely comparable to those in other areas in Italy, Europe and North America, and the results are applicable to other geographical areas.

The aflatoxins are ubiquitous contaminants of food and feed produced by some Aspergillus spp. The effects of these toxins vary from acute, including rapid death, to chronic, like hepatocellular carcinoma. The International Agency for Research on Cancer has classified aflatoxin B1 in Group I carcinogens. They also affect animal health and productions and cause economic losses in agriculture industry. In this first part of the review we discuss the aflatoxins issue: synthesis, absorption, elimination and carry-over of aflatoxins, mechanisms of toxicity and cases of aflatoxicosis worldwide. The second part of the review (to be published in the next issue of Tecnica Molitoria) will analyse the major sources of exposure to aflatoxins and the contamination of food and feed, dedicating a specific chapter to the prevention methods.

The aim of this study was to evaluate the efficacy of acid electrolysed oxidizing water (EOW) in reducing contamination by spoilage bacteria in bovine meat in order to determine if the treatment can limit microbial growth and extend the shelf life of fresh meat. Five batches of bovine meat were collected. Samples were treated with EOW, vacuum-packed and analysed to determine the mesophilic microbial load, count of Enterobacteriaceae, lactic acid bacteria, Brochothrix thermosphacta and Pseudomonas spp. during 20 days of storage at different temperatures (4°, 8°, 12°C). Comparison between data obtained from the analysis of untreated and treated samples showed no significant difference in the samples analysed immediately after treatment and during storage. Treatment by immersion of bovine meat cuts for 45 seconds in EOW has shown to be ineffective in reducing contamination by the bacteria more frequently involved in meat spoilage.

The aflatoxins are ubiquitous contaminants of food and feed produced by some Aspergillus spp.. The effects of these toxins vary from acute, including rapid death, to chronic, like hepatocellular carcinoma. The International Agency for Research on Cancer has classified aflatoxin B1 in Group I carcinogens. They also affect animal health and productions and cause economic losses in agriculture industry. In this review we discuss the aflatoxins issue: synthesis, absorption, elimination and carry-over of aflatoxins, mechanisms of toxicity and cases of aflatoxicosis worldwide. The review analyses the major sources of exposure to aflatoxins and the contamination of food and feed, dedicating a specific chapter to the prevention methods.

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of paratuberculosis. The disease affects cows and other ruminants and causes high economic losses, mainly for dairy production. MAP may also have a role in the development of Crohn’s disease in humans. Infected animals shed viable MAP with milk and faeces and humans may assume MAP via the consumption of contaminated milk and dairy products. Current methods of milk pasteurization are not sufficient to kill all MAP cells present in milk and MAP has been found in raw or pasteurized milk and isolated from cheese. The aim of this paper is to review the current knowledge about MAP in dairy production. We analyzed studies on milk contamination, effect of pasteurization and methods for identification of MAP that can be applied to dairy products.

The aim of the study was to evaluate the influence of cleanliness of cattle slaughtered on hide and carcass contamination as indicated by aerobic colony count (ACC) and Enterobacteriaceae count (EC). Cattle in two slaughterhouses were visually inspected and assigned to a category from 1 (very clean) to 5 (very dirty) based on cleanliness. Fifteen animals for each category were randomly selected in each slaugterhouse and the hides and carcasses sampled and analyzed for ACC, EC. Results showed that the increasing dirt of the cattle was associated with higher ACC and EC on the hides and with higher ACC on carcasses in both slaughterhouse. In one slaughterhouse a correlation between hide cleanliness and EC was shown. The different characteristics of the slaughterhouses may influence the transfer of bacteria from hide to carcass. The study supports the conclusion that the pre-slaughter visual evaluation of animal cleanliness and application of corrective actions can be an effective aid to reduce carcass contamination in both slaughterhouses.