Fatal privet (Ligustrum amurease) toxicosis in Tennessee cows.

Five of 24 cows pastured in a 40-acre field in east Tennessee died after they consumed leaves from a privet (Ligustrum amurease) hedge. Clinical findings included ataxia, recumbency with an inability to stand, depression, greenish nasal discharge, cessation of rumination, normal body temperature, and increased heart and respiratory rates. Differential diagnoses included grass tetany, nitrate toxicosis, and plant toxicosis. Privet toxicosis was confirmed by finding privet in ruminal contents, by the presence of a large quantity of privet in the field, by observing places where this privet had been eaten by the cows, by the immediate cessation of the problem when the cows were removed from the field, and by observing no recurrent problems after the privet was destroyed with a herbicide and the cows were returned to the field.