OBJECTIVE To identify clinical signs associated with oral exposure to black walnut tree (Juglans nigra) wood, nuts, or nut hulls in dogs and to compare clinical syndromes between dogs that ingested wood and dogs that ingested the walnuts or nut hulls.
DESIGN Retrospective case series.
ANIMALS 93 dogs.
PROCEDURES Records of dogs with oral exposure to black walnut wood, nuts, or nut hulls between November 2001 and December 2012 were retrieved from the Animal Poison Control Center database. Records were reviewed, and data regarding signalment; exposure; time of onset, type, and duration of clinical signs; serum biochemical abnormalities; treatment; and response to treatment were collected. Results were compared statistically between dogs that ingested wood and those that ingested nut components.
RESULTS 28 cases involved exposure to wood, and 65 involved exposure to nuts or hulls. Spontaneous vomiting was commonly observed (13/28 [46%] and 31/65 [48%] dogs that ingested wood and nut components, respectively). Neurologic or musculoskeletal signs were significantly more common in dogs that ingested wood (26/28 [93%]) than in those that ingested nuts or hulls (15/65 [23%]). Relative risk of developing neurologic signs after ingestion of wood was approximately 4 times that after ingestion of nuts or hulls.
CONCLUSIONS AND CLINICAL RELEVANCE Ingestion of black walnut wood by dogs resulted in a clinical syndrome in which neurologic or musculoskeletal signs were most frequently reported, whereas ingestion of black walnuts or their hulls was most commonly associated with vomiting. To our knowledge, this is the first report describing 2 different clinical syndromes associated with exposure to black walnut tree components in dogs.