REINDEER IN ALASKA. 57 
RICKETS. 
Rickety conditions are rare in reindeer (PL XXIII, Fig. 2). 
While only occasional cases may be seen, the fact that reindeer crave 
lime salts at certain times of the year indicates that their systems 
lack some essential requirement in mineral matter. Toward the 
end of winter it has been observed that they nibble at each other's 
horns, and short, stubby, chewed horns may be seen, especially on 
the fawns. Does may also be found in this condition, their horns 
having been gnawed off close up to the head. The horns disappear 
from the range soon after they are shed. Reindeer may injure 
themselves by trying to swallow too large pieces of bone. In two 
instances animals were found with pieces wedged tightly beside the 
molars. Dr. F. H. Gambell, in 1904, on St. Lawrence Island, noted 
that they showed craving for calcium salts. 14 In some districts it 
may eventually be found necessary and profitable to feed bone meal. 
PARASITES. 
Parasites appear to be the worst enemies the reindeer have. They 
fall into two classes, being both internal and external. The internal 
parasites will be considered first. 
TAPEWORMS. 
Tapeworm cysts. — Three forms of tapeworm cysts are found in 
reindeer, and all three are conveyed by dogs. The dog is the host of 
the tapeworm and the reindeer is the intermediate host. That no 
misunderstanding may exist, the three forms will be described sepa- 
rately. 
Taenia hydatigena (T. marginata) is a common tapeworm in 
dogs. The mature segments or joints of this worm containing the 
ripe eggs of microscopic size are passed in the feces of the dog, and 
are picked up by the reindeer with their grass or other food. The 
eggs hatch and the young larvae find their way into the body cavity. 
The liver is generally the organ most affected, and frequently 10 or 
12 cysts will be noticed just under the covering. They may also be 
found in the fatty tissues round about the intestines. The cysts have 
the appearance of small bladders filled with clear fluid. The blad- 
der worm, as it is called in this state (Cysticercus tenuicollis) , con- 
sists of a head, neck, and bladder. If a clog is fed on raw offal con- 
taining these bladder worms he will soon develop tapeworms, and 
the more raw offal he gets the more tapeworms he is likely t'o have. 
The damage caused by these bladder worms in reindeer is confined 
principally to the liver, which, because of the parasites, is often ren- 
14 See Georgeson, C. C, Reindeer and caribou : Bur. Animal Ind., Circ. 55, U. S. Dept. 
Agr., pp. 377-390, 1904. 
