Chronological observation of respiratory diseases in a field chicken flock.
D000818:Animals; D002645:Chickens; D004196:Disease Outbreaks; D006192:Haemophilus Infections / Q000662:veterinary*; D009175:Mycoplasma Infections / Q000662:veterinary*; D011201:Poultry Diseases; D012140:Respiratory Tract Diseases / Q000473:pathology / Q000662:veterinary*