.126 TRINIDAD AND TOBAGO BULLETIN. [XIX. 3. 



Treatment — Regulation of hygienic conditions is the essential factor 

 to be considered. The animals should be given proper food and they 

 are best out of doors. The earlj' slaughter of severely affected animals 

 is recommended. 



Sheep Scab. 



Definition — A disease of tht; skin caused by certain members of a 

 class of sramll mites known as Acari. 



Animals affected — Scab is popularly known in animals other than 

 sheep as mange. In sheep three forms of scab are met with (1) Psoroptic 

 scab — this is the common form, (2) Sarcoptic scab, (3) Symbiotic scab. 

 The Sarcoptic parasite will ^ive on other animals and on man : the other 

 parasites live on man onlj- for a few days causing temporary irritation. 



Symx>toms — The condition generally starts on the less woolly parts, 

 and then spreads to all parts of the body. The animals rub themselves 

 against fixed objects and show great signs of satisfaction when scratched 

 M'ilh the hands. If the wool be parted the skin beneath is seen to be red 

 in patches. Small pimples from which a thick fluid exudes are found on 

 the skin. If animals are not treated they become emaciated and die of 

 exhaustion. 



Sarcojitic mange affects the head and ears. Symbiotic mange the 

 lower parts of the limbs, but the symptoms are much less severe. 



Treatment — All animals of an infected IickI should be dipped or 

 washed with a fluid which kills the mites. 



Foot Eot. 



Definition — Foot rot is a disease of sheep and is confined to the 

 claws. The specific cause of foot rot still remains to be demonstrated 

 although everything points to the Necrosis bacillus as the cause. 



Animals affected — The Necrosis bacillus not infrequentlj^ affects 

 other species of animals, chiefly however as a sporadic disease. 



Sijmjytoms — Large numbers of sheep are affected at once. The 

 condition begins with lameness, which is at first slight, later becomes 

 very intense. The coronet and the fetlock are found to be swollen. A 

 fcetid discharge is found in the interdigital space. This discharge 

 continues for a week or two and is succeeded by a cheesy exudation 

 which is always offensive, moistens and macerates the horn, the skin, 

 the tissues in the interdigital space and the region of the heels. The 

 horn separates from the subjacent tissue. The patients are now very 

 lame aiid remain lying for long periods. The animals frequently walk 

 on the kiiees. Finally the claws are lost. 



Treatment — Separate and isolate diseased animals in a scrupulously 

 clean place and provide a di-y bed. Avoid infested pastures and barns 

 for the space of a year. A foot bath, in which some astringenb 

 preparation — solution of Copper sulphate — is placed should be attached 

 to all barns and sheep driven through it once daily. Dressings can also 

 be npplied directly by hand to each sheep's feet. 



