Avian Models for Research in Toxicology and Endocrine Disruption

Abstract

There have been significant strides in our knowledge of the effects of toxicants on birds. This communication presents a brief review of avian toxicology with emphasis on effects of common toxicants that disrupt endocrine system function and control of reproduction, growth, development, stress and calcium-phosphorus homeostasis. For those hormonal systems that act through hypothalamic-pituitary axes, we emphasize current knowledge of the axis ‘‘level’’ at which the toxicants alter endocrine control. The classes of toxicants discussed are acid rain andyor aluminum, organochlorines such as polychlorinated biphenyls (PCBs), fungicides and insecticides, mycotoxins, (PCBs) and petroleum. The use of several types of avian models for endocrine disruption studies is discussed in the context of utility and practicality, developmental modes, species sensitivity and the choice of sentinel species. Promising new approaches for avian toxicological research are considered including shell-less embryos, continuous-flow administration of toxicants to avian embryos, gene microarrays, proteomics and metabolomics.