{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,6,7]],"date-time":"2025-06-07T04:05:01Z","timestamp":1749269101328,"version":"3.41.0"},"reference-count":37,"publisher":"American Veterinary Medical Association (AVMA)","license":[{"start":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T00:00:00Z","timestamp":1749168000000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2025,6,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n<jats:sec id=\"sc_a1\">\n<jats:title>Objective<\/jats:title>\n<jats:p>To investigate the extent of fluid incursion throughout the respiratory tract of anesthetized pigs terminated using 3 different depopulation methods compared to termination by water submersion (H<jats:sub>2<\/jats:sub>O).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a2\">\n<jats:title>Methods<\/jats:title>\n<jats:p>Inclusion criteria included pigs aged approximately 40 days. The study occurred over 2 consecutive days during spring. Pigs were anesthetized and terminated using their assigned method: water-based foam, high-expansion nitrogen foam, carbon dioxide gas, or H<jats:sub>2<\/jats:sub>O. Respiratory tracts were evaluated 3 ways: CT, gross examination, and histopathology. Immediately after death, pigs were CT scanned, and opacity changes were scored. After gross examination, representative tissues were scored microscopically.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a3\">\n<jats:title>Results<\/jats:title>\n<jats:p>48 pigs were assigned to 4 treatment groups of 12 pigs each. Compared to all other methods, H<jats:sub>2<\/jats:sub>O had higher odds of increased opacities on CT in several proximal structures and bronchi and pulmonary parenchyma of multiple lung lobes. All groups had pulmonary petechiae to regional hemorrhages and subpleural hemorrhages. Emphysema aquosum was observed exclusively in H<jats:sub>2<\/jats:sub>O pigs (4 of 12 [33.3%]). Histologically, carbon dioxide gas had 97.8% decreased odds of pulmonary hemorrhage compared to H<jats:sub>2<\/jats:sub>O after accounting for sex.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a4\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Postmortem lesions and CT opacity patterns associated with water-based foam and high-expansion nitrogen foam are dissimilar to H<jats:sub>2<\/jats:sub>O. Foam-based methods involve mechanistic differences from drowning through either environmental or occlusional anoxia, not overt fluid inundation of airways.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a5\">\n<jats:title>Clinical Relevance<\/jats:title>\n<jats:p>Foam-based methods are valuable candidates for US swine production and must be separated from the mislabel of drowning. Our findings provide new information regarding large-scale depopulation tools for emergency response efforts.<\/jats:p>\n<\/jats:sec>","DOI":"10.2460\/ajvr.25.01.0035","type":"journal-article","created":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T13:03:32Z","timestamp":1749215012000},"page":"1-10","source":"Crossref","is-referenced-by-count":0,"title":["Foam-based depopulation methods of swine differ from water submersion based on computed tomography findings and postmortem lesions"],"prefix":"10.2460","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4226-7339","authenticated-orcid":true,"given":"Janice Y.","family":"Park","sequence":"first","affiliation":[{"name":"Department of Veterinary Preventive Medicine, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Magnus R.","family":"Campler","sequence":"additional","affiliation":[{"name":"Department of Veterinary Preventive Medicine, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Justin D.","family":"Kieffer","sequence":"additional","affiliation":[{"name":"Department of Animal Sciences, The College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus, OH"},{"name":"Office of the Attending Veterinarian, The Enterprise for Research, Innovation, and Knowledge, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Turi K.","family":"Aarnes","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Sciences, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eric M.","family":"Green","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Sciences, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Denise","family":"Bailey","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Sciences, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marie R.","family":"Culhane","sequence":"additional","affiliation":[{"name":"Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7040-9686","authenticated-orcid":true,"given":"Andr\u00e9ia G.","family":"Arruda","sequence":"additional","affiliation":[{"name":"Department of Veterinary Preventive Medicine, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0738-8453","authenticated-orcid":true,"given":"Andrew S.","family":"Bowman","sequence":"additional","affiliation":[{"name":"Department of Veterinary Preventive Medicine, The College of Veterinary Medicine, The Ohio State University, Columbus, OH"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1272","reference":[{"key":"B1","year":"2025","unstructured":"CO2 shortage in 2022: a threat to food, beverage, and healthcare. 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