PALISADE WORMS. 401 



Mr. Peter Wilson, M.R.CV.S. in "The Veterinarian," advises 

 the use of thymol (p. 406) for the relief of this disease. 



2. THE THREAD OR MAW WORM {oxyuris curvula) is about 

 an inch and three-quarters in length, when of full size. Its tail 

 end is thin and whip-like; its front end being thicker and terminat- 

 ine: in a curve, somewhat in the form of the crook of a stick. The 

 presence of these parasites produces little disturbance of the animal's 

 general health'; although it may cause irritation about the dock, 

 which will be made manifest by the horse rubbing his tail. Accom- 

 panying these worms, a light yellow waxy substance (the eggs of 

 the parasites) will be found adhering to the skin immediately below 

 the anus. Thread worms, like round worms, frequently come away 

 with the dung. 



Treatment. — To clear out the rectum, back rake (p. 638), give an 

 enema (p. 632) of warm water, and then administer another enema 

 of six ounces of oil of turpentine in half a gallon of linseed oil. If, 

 after a repetition or two of this treatment, the worms are still found 

 in the horse, we may conclude that they are too far up in the 

 intestine to be reached by an enema, and we may consequently treat 

 the -animal in the manner directed for round worms (see preceding 

 page). Anointing the inside of the anus with a little mercurial 

 ointment on the finger, will allay the itching and will hasten the 

 removal of those worms which have taken up their abode near that 

 part. 



3. THE PALISADE WORM {sclerostoma equinum, or strongulus 

 armatus) is a very common parasite in horses of most countries, 

 although its presence in the animal usually remains unsuspected. 

 The pastures on which it is found are generally poor and marshy. 

 Its body, which is grey or brownish-red in colour, is more or less 

 straight and stiff, and its front part is thicker than its hind ex- 

 tremity. It varies a good deal in length ; the male, from § inch to 

 1| inch, and the female, from eight-tenths of an inch to 2 inches. 

 It is about twenty times as long as it is thick. It occurs in the 

 horse in two forms, namely, in an adult and in an immature state 

 (before it ari'ives at puberty). In the former, it implants itself on 

 the mucous membrane of the caecum and large colon, by means of 

 its armed mouth ; and in the latter, it resides chiefly in aneurisms, 

 and in cysts underneath the mucous membrane of the caecum and 

 large colon, but is occasionally found in other organs, such as the 

 brain, testicles and liver. 



In the adult state, the large intestine is sometimes " studded with 

 them. Chabert counted more than LOGO on a surface of two inches, 

 and he estimated the total in one horse at more than a million. 



26 



