Although other infectious diseases sometimes affect turkeys, blackhead
is by far the most destructive ailment. It is caused by one of the
Protozoa and is primarily a disease of the caeca (the blind pouches
of the intestines) and the liver, but the fact that the head of the
affected bird often becomes discolored has given the disease its common
name, blackhead. It attacks turkeys most frequently, but chicks are
often affected by it without showing symptoms; thus the chickens carry
and spread the infection to turkeys when allowed to range with them. A
combination of spotted liver and ulcerated caeca indicates that the birds
have blackhead infection.
Although blackhead affects adult turkeys, it occurs principally among
poults between the ages of 6 weeks and 6 months. It is found to a greater
or lesser extent throughout the United States. The turkeys affected by
blackhead, like all birds having infectious diseases, should be removed
immediately from the flock to prevent the spread of the disease. The best
procedure is to kill the sick birds and burn or bury the bodies, as no
treatment has been found satisfactory. Move the flock to clean ground,
if possible; but if this cannot be done, clean out and disinfect the
roosting place, plow the ground in the yards, and install a system of
yard sanitation. Keep chickens and all other poultry away from turkey
yards at all times in order to prevent infection from this source. The
organisms which cause the disease may be carried by flies, blown with
dust, conveyed in contaminated soil on the feet of the caretaker, or
spread for considerable distances in other ways.
Several measures for preventing blackhead are practiced, the chief of
which are: (1) Obtaining eggs or stock from flocks known to be healthy;
(2) quarantining and worming all new stock; (3) cleaning and changing
the litter at least weekly during the brooding period; (4) keeping both
young and mature turkeys on clean ground at a considerable distance from
chickens; (5) excluding, so far as possible, pigeons, sparrows, and
persons from the turkey houses and yards; (6) frequently cleaning and
occasionally disinfecting growing houses, feed troughs, and all other
equipment; (7) feeding only in clean feeders, never on the ground; (8)
immediately killing and deeply burying or completely burning all diseased
birds; and (9) eliminating all stagnant water pools where the turkeys
range. Clean range, clean quarters, clean feed, and clean water are most
important.