6 
BULLETIN 3 8, PUERTO RICO EXPEEIMENT STATION 
this organism and extensive ulcers are found, especially in the 
caecum. Other protozoa, such as amoeba, spirochetes, and tri- 
chomonads, are also found in the intestinal tract. 
Specific treatments for the protozoan and filth-borne diseases 
in pigs are unknown. Pigs should be farrowed and raised in dry, 
bare lots and careful attention should be given to the details of 
sanitation. Food and water should be given in containers that 
will not allow contamination of the contents with manure. Scrub- 
bing the sow before farrowing, as previously mentioned (p. 4), 
may help to prevent infestations by protozoa among sucking pigs. 
LUNGWORM 
The lungworms, M etastrongylus elongatus and C hoerostrongylus 
pudendotectus (fig. 2, B), are slender white worms varying from 1 
to 5 cm (approximately y 2 to 2 inches) in length. They are found in 
the air passages of the lungs. 
Life history. — These worms require earthworms as intermediate 
hosts. The eggs are coughed up, swallowed, and pass out with the 
feces and are ingested by earthworms. Pigs become infested by eating 
i nf ested earthworms. 
Impwtance. — Lungworms are the most common of the more impor- 
tant parasites affecting the»pig. They are most abundant in pigs 
raised in the wet coastal and mountain areas. Pigs on an open range 
often become heavily infested. 
Symptoms and lesions. — The disease is characterized by a cough. 
Heavy infestations may result in pneumonia. Lungworms may be 
fatal to young pigs. Infested lungs are conspicuous because of the 
whitish colored areas on the surface, usually near the tips of the 
larger lobes. 
Treatment. — Medicinal treatment should not be attempted. Sick 
animals sould be placed in clean, dry pens and given an abundance 
of food. 
Prevention. — For unconfined pigs the frequent cleaning and proper 
disposal of the manure around the feeding and sleeping quarters or 
from any area where the pig is in the habit of depositing its drop- 
pings would eliminate much of the infective material. Pigs wander- 
ing farther afield would be less subject to a concentration of infection. 
Infestations among confined pigs can be largely prevented by 
cleaning up all manure accumulations. The concreting of the entire 
hog lot would materially aid in eliminating these worms as well as 
others but its cost would limit such construction to exceptional cases 
only. These worms are unimportant among hogs confined in dry, 
bare lots. Pigs should be raised under the kidney- worm-control plan 
or by the bare-lot method. 
The practice of inserting a wire ring in the nose of the pig to 
prevent rooting in the soil is probably an effective control measure 
for lungworms and also thorn-headed worms. 
KIDNEY WORM 
The kidney worm, Stephamwrus dentatm (fig. 2, ^4), is a thick, 
mottled worm from 2 to 4.5 cm (approximately % t° 1% inches) 
Long. As adults they are located in the abdominal viscera, espe- 
cially in the Tat surrounding the kidneys. 
