STOMACH WORMS IN SHEEP: 
PREVENTION AND TREATMENT. 
CONTENTS. 
Page. 
How can one tell when sheep have stomach wormS?.............. 0222s cece eee ne cence eee eee eee nene 3 
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How-should infested: sheep: or lambs be-treated!? ...- 5 054 5 )5 2 AL Ae ee ee 4 
How; doisheep, boecomoainiested by Stomach WOrMsS 2s. .' ccc sete ass gece oh cnemic eens ages star neice n 6 
What methods can be employed to prevent loss from stomach worms?.......................-..--- 8 
NE of the most serious problems of owners of farm sheep is the 
prevention of injury and loss by stomach worms. This para- 
site (Hemonchus contortus) has been known in this country for many 
years and is common in farm flocks, particularly during wet summers. 
It has been studied by the Zoological Division of the Bureau of 
Animal Industry and the principal facts in its life history have been 
determined. Methods of treatment and of prevention are still under 
investigation by that division, and although the methods have not 
yet been perfected, what has been learned is.sufficient to show how 
affected sheep or lambs can be treated successfully and, what is of 
ereater importance, how they may be raised in such a way as practi- 
cally to overcome the danger. 
What is known of this parasite and the methods of prevention and 
control may be presented as answers to practical questions, as 
follows: 
HOW CAN ONE TELL WHEN SHEEP HAVE STOMACH WORMS? 
Kither lambs or old sheep may be affected by stomach worms at 
any time of the year. The trouble may be noticed first in lambs 
about the middle of summer, though it may be earlier, according to 
the part of the country and the temperature and moisture of the 
season. 
In many flocks the first knowledge of the trouble is gained through 
the death of one or more lambs. [If the flock is under careful obser- 
vation, however, signs of stomach-worm disease will be noticed 
earlier. Dullness and lack of thrift are among the first indications. 
Scouring is often present. These conditions may result from other 
causes, but when due to stomach worms, they are accompanied with a 
very pale, bloodless appearance of the skin and of the mucous mem- 
branes of the eyes and mouth. The whiteness of the skin has caused 
the trouble to be known in some sections as ‘‘paper skin.’’ In many 
cases there is a watery swelling under the jaws. 
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