i 



REINDEER IN ALASKA. 57 



,j, RICKETS. 



Eickety 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 

 and 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 

 nstances animals were found with pieces wedged tightly beside the 

 nolars. Dr. F. H. Gambell, in 1904, on St. Lawrence Island, noted 

 ihat they showed craving for calcium salts.^* In some districts it 

 ji&y eventually be found necessary and profitable to feed bone meal. 



PARASITES. 



Parasites appear to be the worst enemies the reindeer have. They 

 "all into two classes, being both internal and external. The internal 

 parasites will be considered first. 



jj TAPEWORMS. 



^Tapeworm cysts. — Three forms of tapeworm cysts are found in 

 ^eindeer, and all three are conveyed by dogs. The dog is the host of 

 he tapeworm and the reindeer is the intermediate host. That no 

 nisunderstanding may exist, the three forms will be described sepa- 

 ately. 



Taenia hydatigena (T. marginata) is a common tapeworm in 

 logs. The mature segments or joints of this worm containing the 

 ipe eggs of microscopic size are passed in the feces of the dog, and 

 Te picked up by the reindeer with their grass or other food. The 

 :ggs hatch and the young larvae find their way into the body cavity. 

 '?he liver is generally the organ most affected, and frequently 10 or 

 2 cysts will be noticed just under the covering. They may also be 

 ound in the fatty tissues round about the intestines. The cysts have 

 he appearance of small bladders filled with clear fluid. The blad- 

 ler worm, as it is called in this state {Cysticercus tenuicolUs), con- 

 ists of a head, neck, and bladder. If a dog is fed on raw offal con- 

 aining these bladder worms he will soon develop tapeworms, and 

 he more raw offal he gets the more tapeworms he is likely to have, 

 ^he damage caused by these bladder worms in reindeer is confined 

 »rincipally to the liver, which, because of the parasites, is often ren- 



1* See Georgeson, C. C, Reindeer and caribou : Bur. Animal Ind., Circ. 55, U. S. Dept. 

 gr., pp. 377-390, 1904. 



