{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T14:22:43Z","timestamp":1780323763775,"version":"3.54.1"},"reference-count":7,"publisher":"American Veterinary Medical Association (AVMA)","issue":"12","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2002,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n\t\t\t\t<jats:p>\n\t\t\t\t\t<jats:bold>Objective<\/jats:bold>\u2014To determine effects of sedation\nachieved by xylazine (XYL) or acepromazine (ACE) on\ncardiopulmonary function and uterine blood flow in\ncows in late gestation.<\/jats:p>\n\t\t\t\t<jats:p>\n\t\t\t\t\t<jats:bold>Animals<\/jats:bold>\u20148 cows between 219 and 241 days of gestation.<\/jats:p>\n\t\t\t\t<jats:p>\n\t\t\t\t\t<jats:bold>Procedure<\/jats:bold>\u2014Doses of ACE (0.02 mg\/kg) or XYL (0.04\nmg\/kg) were administered IV. Measurements were\nobtained to determine cardiopulmonary effects and\noxygen delivery to the uterus.<\/jats:p>\n\t\t\t\t<jats:p>\n\t\t\t\t\t<jats:bold>Results<\/jats:bold>\u2014Heart rate was not significantly affected by\nadministration of ACE, but it decreased markedly after\nadministration of XYL. Uterine artery flow was\ndecreased at all times by XYL and was always less\nthan for ACE. Xylazine increased uterine vascular\nresistance through 30 minutes and caused reduced\nPaO<jats:sub>2<\/jats:sub> and increased PaCO<jats:sub>2<\/jats:sub> at all time periods.\nAcepromazine caused a 5% decrease in PaO<jats:sub>2<\/jats:sub> only at\n5 minutes. Xylazine reduced oxygen delivery by 59%\nat 5 minutes and 32% at 45 minutes. In contrast, ACE\ncaused a nonsignificant reduction of oxygen delivery\nby 16% at 15 minutes and a return to baseline values\nby 45 minutes<\/jats:p>\n\t\t\t\t<jats:p>\n\t\t\t\t\t<jats:bold>Conclusions and Clinical Relevance<\/jats:bold>\u2014Xylazine\nmarkedly reduces flow and availability of oxygenated\nblood to the uterus, which may critically impair delivery\nof oxygen to the fetus at a stressful and important time\nof development or delivery. Acepromazine was associated\nwith slight reductions of much shorter duration.\nWhen XYL is used to sedate pregnant cows, it could\nimpose physiologic distress on the fetus and potentially\nincrease fetal morbidity and mortality. When sedation\nof the dam is desirable, ACE could be an alternative\nto XYL. (<jats:italic>Am J Vet Res<\/jats:italic> 2002;63:1695\u20131699)<\/jats:p>","DOI":"10.2460\/ajvr.2002.63.1695","type":"journal-article","created":{"date-parts":[[2006,1,23]],"date-time":"2006-01-23T18:27:26Z","timestamp":1138040846000},"page":"1695-1699","source":"Crossref","is-referenced-by-count":47,"title":["Cardiopulmonary effects of xylazine and acepromazine in pregnant cows in late gestation"],"prefix":"10.2460","volume":"63","author":[{"given":"David S.","family":"Hodgson","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colin I.","family":"Dunlop","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Phillip L.","family":"Chapman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John A.","family":"Smith","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"key":"p_1_398","unstructured":"Corah LR. Relationship of nutrition and dystocia. Agri-Practice 1987;Feb:26-28."},{"key":"p_2_399","doi-asserted-by":"crossref","first-page":"1092","DOI":"10.2527\/jas1973.3751092x","volume":"37","author":"Laster DB","year":"1973","journal-title":"J Anim Sci"},{"key":"p_3_400","doi-asserted-by":"crossref","first-page":"524","DOI":"10.1097\/00000542-197906000-00010","volume":"50","author":"Shnider SM","year":"1979","journal-title":"Anesthesiology"},{"key":"p_4_401","doi-asserted-by":"crossref","first-page":"147","DOI":"10.2460\/ajvr.1994.55.01.147","volume":"55","author":"Dunlop CI","year":"1994","journal-title":"Am J Vet Res"},{"key":"p_5_402","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1152\/ajplegacy.1970.218.1.257","volume":"218","author":"Ladner C","year":"1970","journal-title":"Am J Physiol"},{"key":"p_6_403","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1161\/01.RES.38.4.262","volume":"38","author":"Berman","year":"1976","journal-title":"Circ Res"},{"key":"p_7_404","unstructured":"Riebold TW, Geiser DR, Goble DO. Clinical techniques for food animal anesthesia. In: Riebold TW, Geiser DR, Goble DO, eds. Large animal anesthesia. Ames, Iowa: Iowa State University Press, 1995;41-142."}],"container-title":["American Journal of Veterinary Research"],"original-title":[],"link":[{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/ajvr\/63\/12\/ajvr.2002.63.1695.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/ajvr\/63\/12\/ajvr.2002.63.1695.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/ajvr\/63\/12\/ajvr.2002.63.1695.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,7]],"date-time":"2025-03-07T12:03:00Z","timestamp":1741348980000},"score":1,"resource":{"primary":{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/ajvr\/63\/12\/ajvr.2002.63.1695.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2002,12,1]]},"references-count":7,"journal-issue":{"issue":"12"},"URL":"https:\/\/doi.org\/10.2460\/ajvr.2002.63.1695","relation":{},"ISSN":["0002-9645"],"issn-type":[{"value":"0002-9645","type":"print"}],"subject":[],"published":{"date-parts":[[2002,12,1]]}}}