Fig. 4

Frequency of association between disease-induced mortality and reported symptoms or reported suspected causes, based on all symptoms or causes listed for each reported death event in the populations of chickens, ducks, and Muscovy ducks of the study farms during the 20-month study period. E.g., for 75% of Muscovy duck disease-induced deaths, lethargy was reported. LET: lethargy, weariness; DIG: digestive symptom (diarrhea, flatulence or abnormal color of feces); RES: symptoms related to the lower respiratory tract (dyspnea or amplified respiratory sounds); SUD: sudden death (birds died before any symptoms could be noticed); SC: swollen crop; PW: paralyzed wing; SE: anorexia; CYA: cyanosis; RN: symptoms related to the upper respiratory tract (runny nose); FP: fowl pox; CD: coccidiosis; DRY: dry legs; RH: retraction of the head; PL: paralyzed leg; SULF: intoxication with sulfate; CNS: nervous-system symptoms; SN: shrinking neck