be placed high enough to enter the retropharyngeal recess or low 
enough to enter the larynx (Fig. 80), and that failure to insert the 
capsule well back frequently results in the animal spitting out the 
capsule at the first opportunity after it is released. 
Fig. 80. Vertical section through the median longitudinal line of a swine’s head, 
showing the median pharyngeal recess, a pocket about 1.5 inches long. From Hall, 
1920, after Sisson. 
FEED MECHANICALLY PROTECTS WORMS 
As a result of the difficultaies in drenching swine or giving them 
capsules, there is a persistent demand for an anthelmintic that can be 
given to swine in feed with satisfactory results. Such a procedure 
may be developed or may exist at present, but the writer is not familiar 
with anything of the sort and all our experience up to the present in¬ 
dicates that the feed dilutes and mechanically protects the worms, 
and that the amounts ingested vary too greatly with different animals 
to ensure either safety on one hand or efficacy on the other. How¬ 
ever, it may prove advantageous to give saline purgatives to swine in 
a light soft feed two or three hours after anthelmintic treatment, and 
this method of obtaining purgation is being used by some veterinarians. 
Fig 2 Speculum and syringes with attached tubes for dosing swine by stomach tube. 
From Young, 1923. 
97 
