380 ANNUAL REPORTS OP DEPARTMENT OF AGRICULTURE. 



and to the study of changes which take place in meats placed in cold 

 storage. A wide variety of other topics will be taken up, but as these 

 are of minor importance, it does not seem necessary to enumerate 

 them at this time. 



THE ZOOLOGICAL DIVISION. 



The Zoological Division, under Dr. B. H. Ransom, chief, has con- 

 tinued the investigation of parasitic diseases of animals and the 

 study, collection, and determination of animal parasites. 



ROUNDWORMS OF SHEEP. 



The investigations relative to stomach worms and other round- 

 worms of sheep have been continued. Important facts concerning 

 these parasites have been determined during the investigations, which 

 have been in progress a numlicr of years. As yet, however, no fully 

 tratisfactory methods of dealing with the stomach worm have been 

 discovered. 



A new species of roundworm, Ostertagia hullosa, has been found 

 in sheep in several of the States in the Rocky Mountain region. 



Gin IN SHEEP. 



No new centers of gid infection have been found during the year. 

 During the year 104 imported sheep dogs, quarantined in accordance 

 with Bureau of Animal Industry Order 176, were examined for tape- 

 worms by means of microscopic examination of the feces. Twenty- 

 seven of these dogs were found to be infected with tapeworms. All 

 of the infested dogs were treated with ta^niafuges under the super- 

 vision of the Quarantine Division and released after the expulsion 

 of the parasites and after further microscopic examination showed 

 the absence of tapeworm eggs from the feces. As it has been found 

 impossible to distinguish between the gid tapeworm and other tape- 

 worms of the dog on the basis of the eggs found by microscopic 

 examination of the feces, all of the dogs that show tapeworm eggs in 

 the feces resembling the eggs of the gid tapeworm are required to be 

 treated with ta3niafuges before they are released. 



TAPEWORMS or SHEEP. 



An investigation of an important parasite of western sheep, namely, 

 the fringed tapeworm, Thysanosoma actinioides^ has been in progress 

 since the spring of the preceding fiscal year. Through the courtesy 

 of a ranch owner near Amo, Colo., the necessary facilities have been 

 provided for a study of the life history of the parasite, and laboratory 

 facilities have been provided through the courtesy of the authorities 

 of Colorado College, Colorado Springs, Colo. The investigation was 

 suspended during the winter, but was resumed in the spring. The 

 first season's work indicated quite clearly that direct infection from 

 sheep to sheep does not occur, but that some intermediate host is 

 necessary. Experiments in the treatment of sheep to free them from 

 the parasite showed that male fern and carbon bisulphid were 

 inefficacious. A third remedy, a proprietary preparation advertised 



