{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T03:51:39Z","timestamp":1791517899130,"version":"4.3.4"},"reference-count":57,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,26]],"date-time":"2022-02-26T00:00:00Z","timestamp":1645833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Agriculture, Environment and Rural Affairs (DAERA)","award":["18\/3\/02"],"award-info":[{"award-number":["18\/3\/02"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Bovine tuberculosis remains a challenging endemic pathogen of cattle in many parts of the globe. Spatial clustering of Mycoacterium bovis molecular types in cattle suggests that local factors are the primary drivers of spread. Northern Ireland\u2019s agricultural landscape is comprised of highly fragmented farms, distributed across spatially discontinuous land parcels, and these highly fragmented farms are thought to facilitate localised spread. We conducted a matched case control study to quantify the risks of bovine tuberculosis breakdown with farm area, farm fragmentation, fragment dispersal, and contact with neighbouring herds. Whilst our results show small but significant increases in breakdown risk associated with each factor, these relationships were strongly confounded with the number of contiguous neighbours with bovine tuberculosis. Our key finding was that every infected neighbour led to an increase in the odds of breakdown by 40% to 50%, and that highly fragmented farms were almost twice as likely to have a bTB positive neighbour compared to nonfragmented farms. Our results suggest that after controlling for herd size, herd type, spatial and temporal factors, farm fragmentation increasingly exposes herds to infection originating from first-order spatial neighbours. Given Northern Ireland\u2019s particularly fragmented landscape, and reliance on short-term leases, our data support the hypothesis that between-herd contiguous spread is a particularly important component of the region\u2019s bovine tuberculosis disease system.<\/jats:p>","DOI":"10.3390\/pathogens11030299","type":"journal-article","created":{"date-parts":[[2022,2,27]],"date-time":"2022-02-27T20:48:33Z","timestamp":1645994913000},"page":"299","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Investigating Farm Fragmentation as a Risk Factor for Bovine Tuberculosis in Cattle Herds: A Matched Case-Control Study from Northern Ireland"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9023-8500","authenticated-orcid":false,"given":"Georgina","family":"Milne","sequence":"first","affiliation":[{"name":"Agri-Food and Biosciences Institute (AFBI), Belfast BT4 3SD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jordon","family":"Graham","sequence":"additional","affiliation":[{"name":"Agri-Food and Biosciences Institute (AFBI), Belfast BT4 3SD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"McGrath","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Environment and Rural Affairs (Area Based Scheme), Londonderry BT48 6AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raymond","family":"Kirke","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Environment and Rural Affairs (Veterinary Service Animal Health), Limavady BT49 9HP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wilma","family":"McMaster","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Environment and Rural Affairs (Land Parcel Identification System), Ballymena BT43 6HY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0296-4586","authenticated-orcid":false,"given":"Andrew William","family":"Byrne","sequence":"additional","affiliation":[{"name":"One-Health Unit, Department of Agriculture, Food and the Marine, D02 WK12 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1051\/vetres\/2009033","article-title":"Classification of worldwide bovine tuberculosis risk factors in cattle: A stratified approach","volume":"40","author":"Humblet","year":"2009","journal-title":"Vet. 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