January 2018

Signalment (JPC # 1947999):  Hampshire ewe

HISTORY:  This tissue is from a 4-year-old Hampshire ewe that became ill 36 hours after initial access to a new field. Clinical signs included salivation, mydriasis, tremors, ataxia, and paresis. 

HISTOPATHOLOGIC DESCRIPTION:  Kidney:  Multifocally and predominantly within the cortex, tubules are ectatic, expanded up to 4 times normal, and lined by epithelium that is either attenuated, degenerative (characterized by pale, vacuolated cytoplasm), necrotic (characterized by fragmented, hypereosinophilic cytoplasm and pyknosis), or regenerative (characterized by increased mitotic activity and large pale basophilic nuclei with a high nuclear to cytoplasmic ratio and piling up of epithelium).  Tubules often contain intraluminal yellow, translucent, variably shaped, angular, prismatic, anisotropic crystals; rare small amounts of eosinophilic amorphous material (protein); rare sloughed epithelial cells; or, intensely basophilic acellular, fragmented material (mineral).  The interstitium and perivascular connective tissue are mildly expanded by eosinophilic amorphous fluid (edema), eosinophilic beaded to fibrillar material (fibrin) and mild hemorrhage admixed with low numbers of neutrophils, lymphocytes and plasma cells. 

MORPHOLOGIC DIAGNOSIS:  Kidney, tubules:  Degeneration and necrosis, diffuse, moderate with marked tubular ectasia and numerous intratubular oxalate crystals, breed unspecified, ovine.  

ETIOLOGIC DIAGNOSIS:  Oxalate nephrosis 


Halogeton glomeratus (halogeton); Sarcobatus vermiculatus (greasewood); Rheum rhaponticum  (rhubarb); Oxalis spp. (sorrel, soursop); Rumex spp. (sorrel, dock); Amaranthus sp. (pigweed)
Beta spp. (beet, marigold); Brassica spp. (cauliflower, broccoli, kale, rape); Chenopodium album (lamb’s quarters); Portulaca oleracea (purslane); Salsola kali (Russian thistle); Setaria spp. (tropical grass)








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