HEAVY METAL POISONING IN BIRDS

1. What metals cause heavy metal poisoning?

Heavy metal poisoning is commonly caused by lead, zinc and copper.

2. What are the sources of heavy metal poisoning?

There are many sources of heavy metal poisoning in a bird’s environment. Examples include:

  • Galvanised cages and aviaries which may leach zinc

  • Rusty toys such as bells, metal ties and quick-link zinc clamps (to attach toys to cages)

  • Galvanised dishes release metal into the food and water

  • Some treat sticks contain large amounts of zinc in the wire holders

  • Lead paint and solder on walls and windowsills

  • Copper wires from electrical appliances

  • Costume jewellery

  • Most powder coating on bird cages is safe, however some powder coating uses zinc to speed the curing process and this can still be toxic.

3. What are the clinical signs of heavy metal poisoning?

The most common signs are:

  • Gastrointestinal, pancreatic and kidney problems (vomiting and diarrhoea)

  • Polyuria and polydipsia (increased drinking and increased urine)

Other signs include:

  • Dull appearance, listlessness and weakness

  • Weight loss

  • Seizures

  • Dysphagia (difficulty eating)

  • Skin, feather and feet chewing

4. Is heavy metal poisoning fatal?

In untreated birds it is often fatal. Birds with chronic poisoning often have signs of intermittent tiredness, dysphagia and depression.

5. How is heavy metal poisoning diagnosed?

  • History of exposure to sources of heavy metal and clinical signs.

  • Radiology (x-rays) to show the presence of metallic foreign bodies may be helpful but will not always be diagnostic.

  • Blood testing for lead levels. Blood tests for zinc and copper levels are available but are not always reliable.

  • Blood tests may also be useful to check for organ damage and anaemia.

6. What is the treatment for heavy metal poisoning?

  • Injections of calciumEDTA twice daily for 3-7 days may be necessary to chelate the metal.

  • Tube feeding with bulk cathartics to bind metal still present in the intestine.

  • Additional treatments that may be needed include: high energy food supplements, a heat source, treatment of secondary infections and intravenous or subcutaneous fluids.