?. Nov., 1907.] Diseases of Farm Animals. 645 



Colour has been lent to the arguments of those theorists who hold that 

 all footrot is contagious by the circumstance that the disease occurs epi- 

 zootically ; that is, it affects a large number of sheep simultaneously or 

 successively, but such occurrence is in many instances satisfactorily 

 accounted for h\ the fact that the whole flock is placed under similar 

 operating causes. The disease being contracted by sound sheep on being 

 introduced amongst affected sheep proves nothing more than that what will 

 act as a cause in one sheep will also act as a cause in others that may be 

 exposed to it. Finally, in these days of germs and germ-seekers the absence 

 ■of any positive evidence of bacterial causation is significant, for it is now 

 necessary, when claiming a specific or contagious character for a disease, 

 to affirm its bacterial nature by incontrovertible proof, and as regards the 

 ordinary footrot this has not been done. 



Simple Footrot. 



Simple footrot can only, then, be considered contagious in the false 

 sense that a septic wound or running sore may be contagious ; that is, the 

 caustic discharges and horn scales from affected sheep, by being trampled 

 and paddled upon by other sheep, and so brought in contact with the soft, 

 tender horn between the toes (perhaps already inflamed and sore), may 

 •cause such irritation as will serve to set up inflammation of a character 

 which, fostered by the natural dirtiness of the situation, develops into 

 footrot. 



While not at all likely to terminate fatally, footrot is, nevertheless, a 

 source of heavy monetary losses to pastoralists, in that the pain and irrita- 

 tive fever which accompany moderatively severe cases prevent that' rapid 

 growth and thriving condition which are essential to profitable sheep culture. 

 The fleece suffers from the unthriftiness, and fattening is tardy for the 

 same reason, and also because there is disinclination to " forage " for the 

 best " picking." 



Nature and Causes. — Footrot is essentially an inflammation of the 

 tissues of the foot subjacent to the horn, varying in intensity from a mere 

 erosion or sore to a sloughing ulceration, and caused by an injury of some 

 kind. It is often primarily caused by a softening of the horn of the feet, 

 particularly that thin and naturally tender horn on the inner aspect of 

 the claws, whereby it becomes greatly more prone to injury of any kind. It 

 is hence particularly prevalent in low-lying, marshy, or undrained situa- 

 tions, where the feet are Likely to be kept continuously soft and spongy. 

 When in this state the slightest injury from rough grass, stubble, stones, 

 -or uneven ground, soon becomes a sore, and through inoculation with dirt 

 and decomposing organic debris, ulceration and under-running of the horn 

 with matter quickly follow. Footrot is also met with in sheep grazing on 

 high, gravellv land, or which have travelled long distances over hard 

 ground, and in these cases the disease is simply an extension of footsore- 

 ness. Again, when found on loose, sandy soils its occurrence is due to 

 the fact that on these soils there is little wear of the horn ; the claws be- 

 come long and overgrown, and subsequently mechanically inflamed. As 

 a general rule, the disease prevails most on moist land in wet weather, 

 and on dry land in dry weather. 



Symptoms. — Lameness or apparent difficulty in walking and frequent 

 inchnation to rest are first noticed ; in a few days the hobbling, painful 

 gait is accentuated, ana the sheep begins to fall away in condition and 

 assume a lank appearance. On examination the affected feet will be found 



