Jan. 20,1923 
Carbon Tetrachlorid as an Anthelmintic 
165 
Bird No. 10.—Weight 1.51 kilos, dose rate 2 cc. per kilo, no worms 
passed in 4 days; second dose at rate of 5 cc. per kilo, no worms passed 
in 4 days; third dose at rate of 7 cc. per kilo, no worms passed in 3 days; 
fourth dose (7 days after third dose) at rate of 15 cc. per kilo, no worms 
passed in 3 days; post mortem (12 days after fourth dose), no worms 
present. 
Bird No. 11.—Weight 1.33 kilos; dose rate 3 cc. per kilo, passed 1 
Heterakis papillosa in 4 days; second dose at rate of 6 cc. per kilo, no 
worms passed in 4 days; third dose at rate of 8 cc. per kilo, no worms 
passed in 3 days; fourth dose (7 days after third dose) at rate of 18 cc. 
per kilo, no worms passed in 3 days; post mortem (12 days after fourth 
dose), 1 tapeworm in small intestine. 
Bird No. 12.—Weight 1.265 kilos; dose rate 3 cc. per kilo, no worms 
passed in 4 days; second dose (8 days after first dose) at rate of 10 cc. 
per kilo, no worms passed in 3 days; third dose (7 days after second dose) 
at rate of 20 cc. per kilo, no worms passed in 3 days; post mortem (12 
days after third dose), no worms present. 
Bird No. 13.—Weight 1.29 kilos; dose rate 4 cc. per kilo; passed 2 
Ascaridia perspicillum and 5 Heterakis papillosa in 4 days; post mortem, 
no worms present. 
The most striking feature of these experiments is the tolerance of 
chickens for carbon tetrachlorid. The largest single dose administered 
(bird No. 12) was at the rate of 20 cc. per kilo of weight of animal, which 
is approximately 67 times the therapeutic dose rate for removing hook¬ 
worms from dogs and foxes. In a period of 15 days this bird was given 
carbon tetrachlorid in quantities equivalent to a total at the rate of 33 cc. 
per kilo, or no times the therapeutic dose for dogs. Bird No. n was 
given carbon tetrachlorid in a period of 15 days in quantities equivalent 
to a total at the rate of 35 cc. per kilo, or almost 117 times the therapeutic 
dose for dogs; this bird was given one dose of carbon tetrachlorid at 
the rate of 18 cc. per kilo, or 60 times the therapeutic dose for dogs. 
None of the birds showed signs of discomfort or injury as a result of the 
treatment, and on post-mortem examination they appeared normal 
except for some evidence of inflammation in the small intestine of the 
birds given repeated large doses (birds No. 9, 10, 11, and 12). The sur¬ 
vival of these birds and their good condition indicated that no serious 
injury had been caused by the drug. 
As regards efficacy, no worms of the superfamily Spiruroidea—those 
present in these birds being forms which live in the tissues along the 
digestive tract, including Cheilospirura hamulosa in the wall of the gizzard, 
Tetrameres sp. in the proventriculus, and Gongylonema ingluvicola in 
the wall of the crop—were found in the droppings after treatment. 
Apparently, the treatment was ineffective in removing these worms. 
However, it should be noted that none of these worms were found post 
mortem in the five birds which received large and repeated doses, and 
there is a possibility that flooding the digestive tract with large quantities 
of carbon tetrachlorid may have resulted in the death of the worms, with 
the failure to find them in the droppings owing to the worms having been 
destroyed by digestion. These worms are situated in the anterior 
portion of the digestive tract and it seems reasonable to suppose that they 
would be destroyed and digested, at least to an extent which would 
make the fragments unrecognizable in the droppings. It would appear 
quite unlikely that worms would pass through the gizzard without being 
fragmented. 
