The differential diagnosis of catarrhal diseases in fowls formed the basis of a lecture today by Mr. T. G. Hungerford, B.V.Sc.. H.D.A., at the Conference of Stock Inspectors.
Previously, said Mr. Hungerford, these diseases were all called "roup," but that disease group has been divided into infectious laryngotracheitis (which varies a lot in the symptoms shown), infectious catarrh, fowl pox, green feed deficiency disease, and coryza.
The chronic form of infectious laryngotracheitis, and infectious catarrh (the mouth form of fowl pox and green feed deficiency disease), all show some symptoms in common; that is, a bird has "bunged-up" eyes, "cheesy" material in the mouth, nose, throat, and larynx.
In chronic laryngotracheitis and infectious catarrh, the windpipe shows congestion and inflammation. In fowl pox, pustules and pox are seen in the comb and legs. In green feed deficiency disease, there are small yellow nodules about the size of sago grains down the back of the throat. In "per-acute laryngotracheitis," the bird shows bleeding into the windpipe, coughs out blood and later dies.
Infectious catarrh and chronic laryngotracheitis, continued Mr. Hungerford, could only be differentiated in the laboratory.