FUR-SEAL li^DUSTRY. 95 



perhaps can not be identified on such a small amount of material in poor condition. 

 Eight of the foxes were infested with ascarids, the large round worm of the small 

 intestine, which is, at times, sufficiently numerous to cause serious damage. The 

 damage due to ascarid worms is not only that which follows from their presence in the 

 digestive tract but is also due, as recent investigations have shown, to injuries to the 

 lungs occasioned by the passag-s of the larval ascarids from the blood stream to the 

 air passages in the course of their migration through the body. One of the foxes had 

 in the small intestine a number of dipterous larvae which have not yet been identified. 

 It is likely that these larv* were not p.xrasitic but were due to the fox having eaten 

 some foodstuff, possibly meat, which had been flyblown. 



In comment on the foregoing findings it may be said that a feature of considerable 

 interest is the absence of any hookworms. Inasmuch as hookworm disease is one of 

 the most serious pests to be met with in raising foxes or related carnivores, it appears 

 that the island on which these foxes are being raised is a particularly favorable loca- 

 tion from this standpoint. It would seem that conditions on the island are peculiarly 

 unfavorable for maintaining a hookworm infection among foxes, or that the original 

 stock placed on the island was fortunately free from hookworm. In any event it 

 would appear to be worth while to take precautions to keep this island uninfested 

 with hookworm either by not bringing in new stock which might be infected, or if 

 new stock must be brought in by subjecting it first to careful fecal examination to 

 ascertain the presence of hookworms, and the exclusion of infected animals until fecal 

 examination following treatment had shown that the animals were free from infection. 



Of the parasites already present in the foxes the ascarid is probably the most in- 

 jurious, but this worm is readily removable by the use of oil of chenopodium accom- 

 panied by libera! doses of castor oil. The dose used for dogs is one-tenth of 1 mil of 

 wormseed oil per kilo of weight of dog, or 1 mil of oil for a 22-pound dog followed 

 immediately by an ounce of castor oil. The amount of damage due to the Mesoces- 

 toides is problematical. These tapeworms were present in very large numbers, in 

 some instances forming a mass of worms which almost occlude the intestine. It is 

 likely that these worms could be readily removed by treatment with oleoresin of 

 male fern. The dose for dogs is 1 to 2 drams; for foxes it would be advisable to use 

 smaller doses, perhaps 3 to 4 mils. Experiment < indicate that contrary to what is 

 sometimes said, the male fern may be followed immediately by an ounce of castor oil 

 with good results. 



An examination of the viscera other than the digestive tract does not disclose any 

 parasites, nor was the seal meat, which was sent in as a sample of the food used by the 

 foxes, found to be parasitized. The sea urchins were not examined, as we have no 

 reason at present for believing that animals in this group need be suspected of being 

 intermediate hosts or carriers of any sort for the parasites of foxes. 



REINDEER. 



The reindeer herds on St. Paul and St. George Islands maintained 

 themselves in satisfactory condition during 1919. limited use was 

 made of them for furnishing food both for the natives and the Bu- 

 reau's employees. The meat provides a welcome change of diet for 

 all; it compares very favorably with beef. 



A question having been raised as to the adequacy of the natural 

 food supply on the islands for maintaining animals in larger numbers 

 than already existed, the matter was looked into in some detail. It 

 is now believed that no concern need be felt on this account for some 

 years, even with the animals increasing considerably in numbers. 

 For instance, it was found that there was an area of not less than 4 

 square miles on the eastern section of St. George Island covered with 

 rich reindeer moss which had not been touched for months, if at all, 

 during the season. Observations made on St. Paul Island indicate 

 that the nioss reproduces itself there much more rapidly than it does 

 on the mainland of Alaska. 



It is difhcult to establish systematic methods of handling the rein- 

 deer on St. Paul and St. George Islands. The animals are wild and 

 seldom approach within sight of the villages. To domesticate the 



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