370 VETERINARY HYGIENE 



there is evidence to show that a badly infected flock may not be 

 cured by two dippings at short intervals. " There is this important 

 difference, however, that there is satisfactory evidence that scab 

 can be eradicated from infected flocks by carrying out two annual 

 dippings with a short interval between each." 



This same authority says that scab follows a regular course 

 throughout the year. It begins to increase in October, is at its 

 maximum in December and January, and then gradually declines. 

 In June, July, August and September especially July and August 

 the outbreaks are negligible. 



FOOT-ROT OF SHEEP. 



Foot-rot is of two kinds, non-contagious and contagious. The 

 non-contagious form is often mistaken for the contagious variety. 

 It is due to injury to the feet or the coronet, with splitting of the 

 hoof and other injuries that may allow dirt to gain entrance to the 

 underlying parts. Conditions which favour foot-sore, or non- 

 contagious foot-rot, are marshy ground, with resulting overgrowth 

 of the hoof from want of attrition. Overgrown and neglected 

 hoofs are liable to break away and thus leave the sensitive laminae 

 exposed to dirt, gravel, &c. Any injury to the feet will cause 

 foot-sore, such as travelling for long distances on hard roads to 

 sheep sales. A large number of sheep in a flbck may be affected 

 with foot-sore in the same way that a number may be affected with 

 contagious foot-rot. 



Contagious Foot-Rot. This is to a large extent a preventable 

 disease and one that causes a great deal of trouble to the flock- 

 master, considerable pain and inconvenience to the affected animals, 

 with consequent unthrifty condition, and financial loss to the stock- 

 owner. Owing to its contagious nature an early diagnosis is very 

 desirable in order to differentiate between it and the foregoing. 

 The Ministry of Agriculture draws the attention of shepherds to 

 an important distinguishing feature between the two forms.* With 

 non-contagious foot-sore the hoof is primarily affected; with true 

 contagious foot-rot the disease starts originally in the soft tissues 

 of the feet, and, later, the horny structure becomes affected. Con- 

 tagious foot-rot may be present on either dry or wet pastures, and 

 spreads rapidly from one sheep to another. 



PREVENTIVE MEASURES. Careful attention to the sheep, watch- 

 ing for lameness, and examining and trimming damaged feet, with 

 strict isolation of any diseased or suspected sheep, will go far toward 



* Leaflet, No. 154. 



