Oak poisoning (Quercus castaneifolia) mortality report in a sheep flock


1 Department of Clinical Sciences, Faculty of Para Veterinary Sciences, Bu-Ali Sina University, Hamedan-Iran

2 Department of Pathobiology, School of Veterinary Medicine, Lorestan University, Khorram-Abad, Iran

3 Applied Science Education Center of Alborz Farab of Amarlou, Guilan-Iran

4 Department of Pathobiology, Veterinary Reference Laboratory, Iran Veterinary Organization, Tehran, Iran

5 Iran Department of Environment, Gorgan-Iran


Within a few consecutive days, 8 cases of lambs' mortality were reported from the Golestan National Park area (Golestan province). According to the farmer's claims, the disease has occurred only in less than one year old lambs whose  major feeding was  free grazing in the oak rich areas and also collected and manually feeding  with new and fresh buds of this tree.  Ascites, hydrothorax, hydropericarditis, intestine, abomasum and mesenteric subserosal accumulation of fluid, and swelling  of the kidney with cortex hemorrhage was observed in necropsy. Microscopic pathology revealed tubular and glomerular nephritis with tubular hyaline casts and mucosal necrosis with submucosal and serosal edema of GI specimens. Based on available epidemiological data, macro and microscopic pathology, oak poisoning is the most likely cause of mortality in this flock. It seems the major cause of mortality is the high sensitivity of these young animals and furthermore,  the farmers insistence on feeding   them the  fresh buds of this tree.