Custer, T. W., and Ohlendorf, H. M., 1989, Brain cholinesterase activity of
nestling great egrets snowy egrets and black-crowned night-herons: Journal of
Wildlife Diseases, v. 25, no. 3, p. 359-363.

Abstract: 

Inhibition of brain cholinesterase (ChE) activity in birds is often used to diagnose
exposure or death from organophosphorus or carbamate pesticides. Brain ChE
activity in the young of altricial species increases with age; however, this
relationship has only been demonstrated in the European starling (Sturnus
vulgaris). Brain ChE activity of nestling great egrets (Casmerodius albus) collected
from a colony in Texas (USA) increased significantly with age and did not differ
among individuals from different nests. Brain ChE activity of nestling snowy
egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax)
collected in one colony each from Rhode Island, Texas and California (USA) also
increased significantly with age and did not differ among individuals from different
nests or colonies. This study further demonstrates that age must be considered
when evaluating exposure of nestling altricial birds to ChE inhibitors.

Keywords: 

Sturnus, Vulgaris, Casemerodius, Albus Egretta, Thula Nycticorax-nycticorax,
Organophosphate, Carbamate, Pesticide, Rhode Island, Texas, California, USA