CHICKEN POX OR SORE HEAD
An infectious disease that causes considerable loss among chickens and young birds in warm climates

Symptoms. Small, scabby, wart-like growths and eruptions on the head, especially on the comb and the wattles and around the eyes—in bad cases extending to the lids and even the mouth. Chickens and young birds are most commonly attacked by this disease, which spreads rapidly.

Fig. 10.—CHICKEN POX

Cause. The specific organism has not been definitely determined. Chicken pox may be started by the introduction of an infected bird, and mosquitoes and other insects are suspected of being agents in its spread.

Treatment. Prompt treatment may be very successful. Isolate affected birds. Apply tincture of iodine, first scraping off the scabs. Creolin 2%, or other disinfectants, may be used instead of iodine. Dirty coops are a contributing cause, and cleanliness of chicken runs and houses is important. Disinfect soil (see page 13) and woodwork (see page 12) regularly and with extra care when the first cases are noticed. When roupy lesions develop, as is sometimes the case, treat as for roup. (See page 83.)

CHOLERA
A serious and epidemic form of diarrhea for which no remedy is known

Symptoms. Fowls die suddenly with apparently little reason. There are symptoms of diarrhea and examination shows that the feces are a bright yellow or green instead of the normal color. Before death, fowls have fever and may be seen moping and showing evidences of distress. For post-mortem symptoms see page 112.

Cause. A contagious disease, due to bacteria, that, owing to infection of soil and drinking water by birds suffering from the disease, spreads rapidly through a flock. It is often introduced by the purchase of an infected bird that appears at the time of purchase to be well.

Treatment. Prevention by strict sanitary measures is what must be aimed at. It is believed that no cure is known for genuine cases of cholera. Isolate all new birds brought into the flock, especially when cases of cholera are reported in the neighborhood. The bodies of birds that have died of this disease are best burnt without delay. The germ of cholera appears to be both persistent and easily spread, and too much stress cannot be laid on the necessity of preventing its introduction, failing that, of quickly stamping it out. The sacrifice of a few birds to prevent the spread of the disease will be well repaid, for it has been necessary on occasions to kill a whole flock. In some cases it has been found best to move unaffected birds to new quarters.