What are the factors that influence the incidence of Ascites and/or Sudden Death Syndrome (SDS) in broiler chickens?

Factors such as altitude, ventilation, respiratory disease, genetics, temperature, growth rate, pelleted feed, energy-rich diets, salt, vitamin E and selenium status, fish meal, liver disease, viral myocarditis, bacterial endocarditis, plant intoxication, and contamination with chemical compounds can influence the incidence of Ascites and/or SDS in broiler chickens.
The incidence of Ascites and/or SDS in broiler chickens is not influenced by any of the factors mentioned above.