Clark, R.Oyaert, W.Quin, J.I.Alexander, R.A.Clark, R.Sterne, M.Louw, J.G.Van der Reyden, D.De Kock, V.E.2017-02-022017-02-0220171951Clark, R, Oyaert, W & Quin, JI 1951, 'Studies on the alimentary tract of the merino sheep in South Africa. XXI. The toxicity of urea to sheep under different conditions’, Onderstepoort Journal of Veterinary Science, vol. 25, no. 1, pp. 73-78.0330-2465http://hdl.handle.net/2263/58826The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.The dosing of urea into the rumen of sheep caused acute intoxication characterised by atony of the rumen, muscular spasms and sudden death due to circulatory failure. The toxicity of urea was found to depend on the activity of the ruminal flora, as determined by the basic diet, and the presence of available carbohydrate. Toxic symptoms after dosing urea were associated with the formation of ammonia and a high pH of the ruminal contents. They could be prevented or alleviated by the administration of acid.en© 1951 ARC - Onderstepoort and Faculty of Veterinary Science, University of Pretoria (original). © 2017 University of Pretoria. Dept. of Library Services (digital).Veterinary medicineVeterinary medicine -- South AfricaArticle