Blood levels for lead, zinc, iron and copper in raptors from Louisiana

摘要

Raptors are the top predator in many of the environmental niches in which they are found. Because raptors are a top predator, they are susceptible to the bioaccumulation of toxins through the food chain. Bioaccumulation of DDT was responsible for many of the reproductive problems reported in raptors during the last century. Although pesticide toxicosis receives much of the attention in wildlife, heavy metal toxicosis may also result in clinical disease. Heavy metals, including lead, zinc, copper, and iron, have been associated with illness in both wild and domestic birds. The purpose of this study was to determine blood levels of lead, zinc, copper, and iron in raptors presented to the Wildlife Hospital of Louisiana (WHL) (Louisiana State University, School of Veterinary Medicine, Baton Rouge, LA, USA) without apparent toxicosis in order to establish a preliminary reference range. Injured raptors are routinely presented by concerned citizens and public and state officials to the WHL. The majorityof these cases are presented for traumatic injuries. None of the birds sampled in this study were diagnosed with heavy metal toxicosis. Blood was collected from the right jugular vein with a 26-gauge needle (Becton Dickinson and Company, Franklin Lakes,NJ, USA) fastened to a 3-ml Monoject syringe (Sherwood Medical, St. Louis, MO, USA). Blood samples were placed into Microtainer separator tubes (Becton Dickinson and Company) with lithium heparin to avoid contamination associated with other anticoagulants or metals. Zinc and copper assays were performed using atomic absorption spectrophotometery with deuterium background correction. Lead and iron assays were diluted and analyzed using graphite furnace atomic absorption spectrophotometery.