to eat food to which some more or less unpalatable anthelmintic has 
been added. The presence of the food distinctly diminishes the efficacy 
of the anthelmintics, but there is usually some anthelmintic action with 
suitable drugs and as the food dilutes the anthelmintic and in this 
way, as well as mechanically, probably protects the mucosa of the 
digestive tract against irritant action and retards absorption to some 
extent, somewhat larger doses of the drug may be tolerated than 
would be tolerated by a fasting animal which was not given feed with 
the drug. On the other hand, it must be remembered that where a 
drug is mixed with the feed for a number of animals, some animals 
will eat more than others, and perhaps get more of the drug than can 
be well tolerated, whereas other animals will find the drug too distaste¬ 
ful and will get too little to be of value. The animals which eat little 
or none of the medicated feed may be the ones which are most in 
need of treatment. Mass treatments are most used in the case of 
poultry, the animals having the smallest value per head and the ones 
which are kept in the largest numbers as a rule. Chickens and swine 
are probably the most difficult to catch of the domesticated animals, 
and swine are probably the most difficult to treat, these things account¬ 
ing in part for the demand for mass treatments for these animals. 
COMPLICATIONS DUE TO LARVAL WORMS PRESENT 
In a paper on the treatment of horses for the removal of 
worms the writer has called attention to the fact that there are many 
cases in which worms, especially certain nematodes, migrate through 
the body of the host or develop in certain tissues for days, weeks or 
months, and that although anthelmintics may remove all of the adult 
worms present at the time of treatment, these larval or agamic worms 
may enter the lumen of the digestive tract soon after treatment and be 
found there, sometimes, in the case of horse strongyles for example, 
as mature worms very soon after treatment. At present the only 
action that can be taken in this connection is to repeat treatment at 
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