THE DOG AS A CAKRIER OF PARASITES AND DISEASE. 11 
One preventive measure for suppressing gid is, of course, to destroy 
the brains and the coenuri of giddy animals, which can be done by 
burning them or by breaking the skull and covering the brain with 
formaldehyde, sheep dip, or some similar substance. Another meas- 
ure is to administer a vermifuge to sheep dogs and so rid them of 
their tapeworms, and to do this often enough to keep them free 
from tapeworms. But it is obviously of little avail to a sheepman 
to have his own dogs free of tapeworm if his neighbor's dogs or 
ownerless dogs or strays of any sort are free to carry tapeworm 
onto his range or pasture and infect the grazing and thereby infect 
his sheep. From losses originating in this way he must be pro- 
tected by measures looking to the restraint of dogs that recognize 
an owner and the elimination of those that do not. 
Gid has been reported from several States in this country, but it 
is most prevalent in Montana, especially in the northern half of 
that State, where gid has had a foothold for a quarter of a century 
and where the losses for some years total about $10,000. There is 
evidence of the occurrence of gid in Arizona, and outbreaks have 
occurred in recent years in New York, Iowa, and Kansas. There 
have been reports, apparently correct, of its occurrence in Ohio, 
Illinois, Michigan, Missouri, Oklahoma, and Nevada. It is a con- 
stant source of loss in many European countries, and at various 
times has proved a veritable scourge to the sheep industry of these 
countries. 
CYSTICERCUS (MEASLES) IN SHEEP AND OTHER ANIMALS. 
Muscular cysticercosis (" measles ") in sheep. — The presence of 
small bladder worms in mutton has recently been shown by Ransom 1 
to be much more common than had been suspected, and to be due to a 
tapeworm in the dog and not to a tapeworm of man as had been 
supposed. His investigations showed that under careful inspection 
the percentage of affected sheep in this country has amounted to 2 
per cent or more, and that approximately 20,000 sheep carcasses were 
retained in 1912 in abattoirs under Federal inspection on account of 
" sheep measles " due to this parasite. 
The bladder worm, Cysticercus ovis (fig. 6), in the meat of sheep 
is oval and ranges in size from about one-third of a centimeter (one- 
eighth of an inch) to almost a centimeter (three-eighths of an inch) 
in length. Inside of this bladder there is a single tapeworm head, 
in which respect, as well as in size, this cysticercus, as it is called, 
1 Cysticercus ovis, the cause of tapeworm cysts in mutton. By B; H. Ransom. Journal 
of Agricultural Research, U. S. Department of Agriculture, vol. 1, pp. 15-58. 1913. 
