M. Friend Tonie E. Rocke 1999 <p>Avian botulism is a paralytic, often fatal, disease of birds that results when they ingest toxin produced by the bacterium, <i>Clostridium botulinum</i>. Seven distinct types of toxin designated by the letters A to G have been identified (Table 38.1). Waterfowl die-offs due to botulism are usually caused by type C toxin; sporadic die-offs among fish-eating birds, such as common loons and gulls, have been caused by type E toxin. Type A botulinum toxin has also caused disease in birds, most frequently in domestic chickens. Types B, D, F, and G are not known to cause avian botulism in North America.</p> application/pdf en U.S. Geological Survey Avian botulism reports