Histopathological Finding in Urea Toxicity in Cattle

Abstract

Aim:  the aim of this paper was to investigate the histopathological changes in the liver, kidney and lung during urea toxicity in cattle. Place and Duration of Study: In September 2015, Alslait South Dairy Farm, Khartoum, Sudan reported sudden death of some cattle occurred after fed wet concentrated feed prepared from molasses and urea. Methodology: Clinical history and clinical signs were recorded. Among 12 cattle of affected shed, 9 (male=2, female =7) cattle showed clinical sign and within 2-3 hours of onset of clinical sign 7cattle were dead. Postmortem examination was done and liver, kidney, lung and feed samples were collected and sent for laboratory analysis. Result: Results revealed that the male were less prone to be affected (16.7%) with no case fatality (0%) in comparison to highly affected female (50.7%) with very high case fatality (77.7%). On postmortem examination, congested liver and kidney, gastroenteritis with hemorrhagic intestine, edema of lung were observed. Histopathological results revealed necrosis of hepatic cells and renal proximal tubules with dissociation of hepatic cord and infiltration of inflammatory cells in the kidney, congestion of the pulmonary alveolar capillaries, bronchial haemorrhage and emphysema and interstitial pneumonia. Toxicological testing was done on the supplied feed samples and non-protein nitrogen was calculated as 28.18%. Conclusion: in Sudan, urea is used in urea molasses straw preparation as an effective and inexpensive source of non-protein nitrogen (NPN) in feed supplements in the ruminant. Cautions might be taken as urea poisoning may occur in ruminants when incorrect dose or feeds are inappropriately mixed with urea. The onset of the clinical picture may start in a matter of minutes to hours after consumption of urea and in most cases it is acute and can cause heavy mortality.