176 
Journal of Agricultural Research voi. xxm, no. 3 
of carbon tetrachlorid in 60 cc. of castor oil; no worms were passed 
during the next 4 days; post mortem no worms were found. The 
one worm passed after a treatment following a fast of 24 hours. The 
effective dose rate was 0.56 cc. per kilo. This animal showed no bad 
clinical effects or post-mortem lesions from the administration of repeated 
doses totaling 128 cc., or about 4 ounces, of carbon tetrachlorid in the 
course of 3 weeks. 
Tests on another large animal were made as follows: Pig 3350, weigh¬ 
ing 140 pounds (about 64 kilos) was given 32 cc. of carbon tetrachlorid 
in 60 cc. of castor oil; no worms were passed during the next 6 days; 
it was then given 40 cc. of carbon tetrachlorid in 90 cc. of castor oil; 
1 ascarid was passed during the next 7 days; it was then given 50 cc. 
of carbon tetrachlorid in 120 cc. of castor oil; no worms passed during 
the next 4 days; post mortem there were no ascarids, but many nodular 
worms. The effective dose in this case was at the rate of about 0.63 
cc. per kilo. The animal showed no clinical symptoms or post-mortem 
lesions as a result of the administration of 120 cc. (about 4 ounces) of 
carbon tetrachlorid in 13 days. 
A slightly larger dose rate was tested as follows: Pig 3375 was given 
40 cc. of carbon tetrachlorid in 100 cc. of castor oil; it passed 1 ascarid 
during the next 7 days; post mortem it had no ascarids, but had a large 
number of nodular worms. This animal weighed about 100 pounds 
(45 kilos), so the dose rate was about 0.89 cc. per kilo. 
Having established by the foregoing series of tests that the effective 
dose rate necessary for the removal of all ascarids present in swine is 
at least 0.6 cc. per kilo for animals of various weights when properly 
fasted, we returned to the treatment of a series of small pigs as follows: 
Pigs ia, 2a, and 4a, weighing 41, 37, and 34 pounds, respectively, were 
given 15 cc. of carbon tetrachlorid in 60 cc. of castor oil; and pigs 5a 
and 6a, weighing 35 and 26 pounds, respectively, were given 12 cc. of 
carbon tetrachlorid in 60 cc. of castor oil. During the next 6 days pig 
1 a passed 4 ascarids, pig 5a passed 26 ascarids, and pig 6a passed 1 
ascarid, the other pigs passing no worms. All the pigs were then given 
15 cc. of carbon tetrachlorid in 60 cc. of castor oil, and during the next 
week pig 2a passed 1 ascarid. All the pigs were then given 30 cc. of 
carbon tetrachlorid in 60 cc. of castor oil, no worms being passed during 
the next 5 days. Fecal examinations of these pigs had shown a decreasing 
number of worm eggs, but since the largest number were from the pen 
of pig 4a, which had passed no worms, this animal was killed and exam¬ 
ined postmortem. No worms were found, so the eggs present were 
evidently due to contamination of the pen floor from old feces. The 
initial doses for 3 of the pigs were at the rate of 0.77 to 1 cc. per kilo, 
and for the other 2 pigs at the rate of 0.8 to 1 cc. per kilo. This dose 
rate apparently removed all the ascarids from all animals except one, 
and in the case of this animal a second dose at the same rate as the 
first, 0.8 cc. per kilo, removed 1 ascarid, probably the only worm present, 
since the third dose at an increased rate of from about 1 to 1.66 cc. 
per kilo removed no worms from any of the animals. 
It appears from the foregoing that the effective dose rate of carbon 
tetrachlorid for ascarids in swine is at least 0.6 cc. per kilo of weight, the 
best method of administration being in 1 to 4 ounces of castor oil, according 
to the weight of the animal. Preliminary fasting for 24 to 36 hours 
appears to be essential. Occasionally, doses at a higher rate will fail to 
