Thiamin deficiency induced muricide behavior in rats.

An examination of the relationship between the degree of thiamin deficiency and the onset of deficiency induced muricide, revealed that this response appeared abruptly after 31 days of dietary treatment compared to pair-fed or ad lib fed controls. The response was not present after shorter periods of treatment (21 or 26 days). Moreover, once the response appeared at 31 days it was not increased significantly by additional thiamin depletion at 36 days (muricide rats of 48 and 61%, respectively). Pharmacologically induced thiamin deficiency using either pyrithiamin or oxythiamin also induced muricide (38% and 43%, respectively), albeit after a much shorter course of treatment. It appears that muricide induction is not related to thiamin deficiency induced encephalopathy and is probably a reflection of heightened irritability. Nevertheless, the induction of muricide was clearly not related to food deprivation and represents a useful pathognomonic sign that precedes the onset of neurological symptoms indicative of advanced thiamin deficiency.