Summary Although a causal link between Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn’s disease has not been proved, previous studies suggest that the potential routes of human exposure to MAP should be investigated. We conducted a systematic review of literature concerning the likelihood of contamination of food products with MAP and the likely changes in the quantity of MAP in dairy and meat products along their respective production chains. Relevant data were extracted from 65 research papers and synthesized qualitatively. Although estimates of the prevalence of Johne’s disease are scarce, particularly for non‐dairy herds, the available data suggest that the likelihood of contamination of raw milk with MAP in most studied regions is substantial. The presence of MAP in raw and pasteurized milk has been the subject of several studies which show that pasteurized milk is not always MAP‐free and that the effectiveness of pasteurization in inactivating MAP depends on the initial concentration of the agent in raw milk. The most recent studies indicated that beef can be contaminated with MAP via dissemination of the pathogen in the tissues of infected animals. Currently available data suggests that the likelihood of dairy and meat products being contaminated with MAP on retail sale should not be ignored.

Concern over the spread of infectious animal diseases has led to attempts to improve the biosecurity behaviour of farmers. Implicit within these behavioural change strategies are different geographies of knowledge that enact different versions of disease. Some versions are fixed whilst others attempt to live with disease by accommodating difference. This paper explores how these different strategies fare in attempts to promote biosecurity to farmers. The paper compares farmers' responses to 'high-risk' and 'population' strategies of biosecurity behaviour change in relation to bovine tuberculosis in cattle. Drawing on quantitative assessments of biosecurity and farmer interviews, the paper suggests that biosecurity behaviour change initiatives that draw on locally situated practices and knowledges of disease are more likely to have an impact on biosecurity behaviour than those which attempt to standardise biosecurity and disease. Through a process of constant tinkering and rewiring biosecurity to fit local social and ecological conditions, approaches like the high-risk strategy represent one way of living with the uncertainties of disease. It is argued that thinking more broadly about the nature of disease should lead policymakers to re-evaluate the purpose of disease control and their approaches to it. KEY WORDS: biosecurity, animal disease, geographies of knowledge, behaviour change, bovine tuberculosis bs_bs_banner

To implement appropriate and effective disease control programs at the national level, up-to-date and unbiased information on disease frequency is needed. The aim of this study was to estimate the prevalence of selected endemic infectious diseases in the population of dairy herds in Great Britain. Bulk milk tank (BMT) samples from 225 randomly selected dairy farms, stratified by region and herd size, were tested for antibodies against bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1, Mycobacterium avium ssp. paratuberculosis, Leptospira Hardjo, Salmonella spp., Coxiella burnetii, Fasciola hepatica, Neospora caninum, and Ostertagia ostertagi. Furthermore, the presence of BVDV, C. burnetii, and Chlamydia-like organisms was determined by PCR. The apparent herd prevalence was estimated as a weighted proportion of positive herds. The true prevalence was calculated when a test was used with known test characteristics for the cut-off value used. Among unvaccinated herds, the true prevalence of BMT antibodies against BVDV was estimated at 66% [95% confidence interval (CI): 56-77%], M. avium ssp. paratuberculosis 68% (95% CI: 59-77%), bovine herpesvirus type 1 62% (95% CI: 52-73%), Leptospira Hardjo 47% (95% CI: 34-60%), and Salmonella spp. 48% (95% CI: 39-56%). The apparent prevalence of BMT antibodies against C. burnetii was 80% (95% CI: 75-85%), F. hepatica 55% (95% CI: 48-62%), N. caninum 46% (95% CI: 38-54%), and O. ostertagi 95% (95% CI: 91-98%). The BVDV, C. burnetii, and Chlamydia-like antigens were detected in 5 (95% CI: 2-9%), 29 (95% CI: 21-36%), and 31% (95% CI: 24-38%) of herds, respectively. Our results show that dairy cows across GB are frequently exposed to the studied pathogens, which are endemic at high levels with some geographical variations. These prevalence estimates provide a muchneeded basis to assess whether nationwide control programs for the studied pathogens are justified by their potential economic, environmental, and public health implications. Should surveillance and control programs be initiated, the estimates presented here are a baseline against which progress can be assessed. Key words: prevalence, endemic infectious disease, dairy cow, bulk milk, ELISA INTRODUCTIONSeveral infectious diseases of dairy cows such as bovine viral diarrhea virus (BVDV), Johne's disease caused by Mycobacterium avium ssp. paratuberculosis (MAP), infectious bovine rhinotracheitis, and liver fluke are generally regarded as being widespread and endemic in the United Kingdom (Carslake et al., 2011;Sekiya et al., 2013). These diseases are known to have a significant effect on dairy production due to their effects on fertility (Fray et al., 2000;Lanyon et al., 2014;Walz et al., 2015), milk production (Tiwari et al., 2007;McAloon et al., 2016), and, subsequently, culling (Murphy et al., 2006;Smith et al., 2010).In Great Britain (GB) in 2005, the total costs of dairy and beef cattle endemic infectious diseases (disease, control, and prevention) were estimated to be as high as £10 million ($12.4 m...

HighlightsPCR and genomeresolved metagenomics revealed Lak phages in 13 animal species Lak is abundant in the pig hindgut, with potential relevance to growth performance Thirty-four new Lak phage genomes present expanded size range and phylogeny Unique Lak protein families from specific microbiomes suggest animal host adaptation

-A randomised controlled trial was used to investigate the effect of three complex management intervention packages to reduce the burden of E. coli O157 in groups of young-stock on cattle farms in England and Wales. All intervention farms were assigned measures to avoid buying in new animals and having direct contact or sharing water sources with other cattle. Furthermore, package A (7 farms) aimed to keep a clean environment and closed groups of young-stock; package B (14 farms) aimed for improved water and feed hygiene, whilst package C was assigned both A and B. The control farms (26 farms) were asked not to alter their practices. Farms, which were assigned intervention package A, exhibited a 48% reduction in E. coli O157 burden over the 4.5 months (average) of observation, compared to 18% on the control farms. The effect of package A compared to the control farms in a crude intention-to-treat model was RR = 0.26 (p = 0.122). When the risk ratio was adjusted for actual application of the different measures, the effect of intervention package A became stronger and statistically significant (RR = 0.14 p = 0.032). Statistical evidence (p < 0.05) showed that dry bedding and maintaining animals in the same groups were the most important measures within the package and weak evidence (p < 0.1) showed that a closed herd policy and no contact with other cattle may also be of importance. Compliance with the other measures in package A had no influence on the effect of the package. No evidence of effect of the other two intervention packages was found.VTEC (STEC) E. coli O157 / randomised controlled trial / prevention / zoonotic control in cattle