Avian Botulism is a serious neurological disease caused by ingestion of a nerve toxin, produced by the bacteria, Clostridium botulinum
. There are several different strains of C. botulinum
, with each strain producing its own type of toxin---categorized as type A through E. Certain strains are more abundant in particular regions and cause infection to specific species of animals and humans. Waterfowl are most commonly affected by type C toxin, and on occasion types A and E.
Waterfowl, both domestic and wild, are at an increased risk of botulism, due to their dabbling habits in water and mud. C. botulinum
is widespread in soil however requires certain environmental conditions to be met in order for it to produce toxins; these conditions include:
- Warm temperature
- An anaerobic environment (absence of oxygen)
- A protein source
Clinical Signs of Botulism
Botulism acts by blocking nerve function and leads to respiratory and musculoskeletal paralysis. As the disease progresses, different levels of paralysis are observed in ducks. An early indication that a duck has been affected is its inability to fly or dive. The bird might also show attempts to move, using only it's wings. Birds are usually relatively easy to catch.
How do Ducks Get Botulism?
Ducks can get botulism through eating or dabbling in contaminated soil, water, decaying matter, spoiled feed, or from eating maggots harboring C. botulinum
toxins. Decaying animals or vegetation provide both a protein source as well as an anaerobic environment to C. botulinum
. Botulism Type C spores exist along the bottoms of various water sources, which begin to thrive as oxygen levels drop and water temperatures rise.
Fly larvae (maggots) that feed on this decaying material, and eaten by ducks, can also serve as a source of infection for ducks. Ducks need only to eat a handful of maggots to become poisoned by the toxins.