CHAP. in. FOOT ROT. 587 



iii such creatures are wanting in stoutness, consistence, and powers of 

 resistance. They are consequently readily torn, broken, or otherwise 

 deranged under the peculiar conditions to which they are exposed. 



Some authorities regard the disease as contagious, and under certain 

 circumstances it would seem to be so. 1 It is known to result from 

 well denned causes of a common character, such as (1) a febrile condition 

 of the feet induced by long journeys, leading to a dry brittle state of 

 the horn, and subsequent cracking; (2) excessive wear of the hoof 

 and exposure of the sensitive structures within it; (3) the long 

 continued application of wet to the feet, resulting in rotting and tearing 

 of the hoof and the entrance of dirt into the vascular tissues ; (4) it 

 is also seen on sandy and gravelly soils during hot weather, when the 

 hoof becomes dry and brittle, and cracks appear which give lodgment 

 to sand and other foreign matter ; (5) the mechanical irritation of 

 short stubble acting on the cleft of the foot is a fruitful cause in wet 

 weather ; (6) it also results from the impaction of hard clay between 

 the digits, and from standing on hot litter. Many examples of the 

 last-named cause are seen in ewes when confined to the lambing pens. 



Symptoms. Lameness, more or less severe, is observed in one or 

 more limbs. The affected feet are hot and tender, the horn is ragged 

 and easily torn. The vascular structures are laid bare, and in severe 

 cases the digits are much swollen, and general inflammation with 

 deformity of the entire foot exists. When the disease continues for 

 any length of time, locomotion is interfered with, the animal fails to 

 seek its food, and loses flesh. Sometimes the bones of the feet are 

 affected, and there is much suffering and constitutional disturbance. 



Treatment. The first step in the course of treatment is to remove 

 the diseased sheep on to a dry surface, such as a well littered yard or 

 shed. The feet are then to be examined, and all loose horn carefully 

 removed with a sharp knife. One of the many caustic or astringent 

 agents in common use may next be applied to the diseased part if 

 necessary. The remedies usually emploj-ed are the mineral acids 

 nitric, sulphuric or hydrochloric or a solution of a caustic or of 

 bichloride of mercury. The astringent agents are the sulphates of 

 copper, iron, or zinc, or alum, used in the form of saturated solution. 



Corrosive mixtures should not be too frequently applied, and the 

 feet should be kept dry during the course of treatment. 



A method of dealing comprehensively with a large number of sheep 

 is described on page 519. 



LIVER EOT. This is one of the most destructive maladies of sheep, 

 and in some seasons flocks have been decimated by its ravages. The 

 disease is associated with the presence in the liver of trematode worms, 

 known as liver flukes. The mature fluke has the same shape as a sole 

 or a flounder, but is not much more than one inch long. The fluke 

 parasite (Fasciola hepatica, or Distoma hepatica) has a complicated 

 life- history, involving an alternation of generations. The eggs of the 



1 The reader may be referred to the Royal Agricultural Society's pamphlet, Contagious 

 Foot Rot in Sheep, by Sir George Brown, O.B. Price Gd. London : John Murray. 1892. 



