1874 DISEASES PECULIAR TO SOUTH AFEICA 



on low-lying spots are infected with stinging gnats, mosquitoes, etc., and 

 it is almost certain that insects of this nature carry the infection, for in 

 winter and spring time, when these insects disappear, the disease also 

 disappears. 



Period of Incubatioili When the disease is produced under natural 

 conditions, the jDcriod of incubation is not known, but when experi- 

 mentally produced. Veterinary Surgeon Spreule of Cape Colony, found 

 it to be from two to five days. 



How To Know Iti In a typical case, the onset is marked by fever; 

 the temperature, which may be erratic, ranging from 104 degrees F. to 

 106 degrees F., the morning temperature being much lower than one 

 might expect. The fever period lasts from five to seven days, a decided 

 drop being noticed when the eruption takes place. Prior to this it may 

 be noticed that the sheep is getting thin and does not feed so well as 

 usual. The first symptoms that attract attention are swelling of the 

 lips and frothing at the mouth, and a catarrhal discharge from the 

 nostrils, and on examination of the mouth, it is seen that the lining mem- 

 brane is of a blue color. In mild cases the only indication may be sores 

 inside the mouth and on the tip of the tongue. The tongue miiy be 

 gangrenous, and in very severe cases become badly infected and of a 

 dark blue color; the organ swells until it quite fills the mouth, making 

 swallowing impossible. There is a copious discharge from the mouth; 

 the lips become greatly swollen, while the usual discharge, growing 

 profuse, dries on the nose, causing difficulty in breathing. Some times 

 diarrhoea sets in, blood being passed, which is always a fatal sign, but 

 as a rule, the fseces are almost normal except for some slimy mucous 

 discharged along with them. 



The lesions in the mouth heal in five to seven days, the appetite 

 returns, the feet become tender, swollen and painful round the coronets; 

 sometimes all four feet become affected, but commonly the front feet 

 only. There is much thirst during both the febrile and eruptive stages, 

 and sometimes when the sheep begin to feed well vomiting may super- 

 vene, especially if they have free access to water. The contents of the 

 stomach, vomited, passes down the nostrils, and in many cases is inhaled 

 into the lungs, thus setting up a fatal pneumonia, i. e.,- septic inflamma- 

 tion of the lungs. In young animals, especially if in poor condition the 

 disease runs a very rapid and fatal course. The sheep are very much 

 emaciated, and persistently lie down, although the feet may not be af- 

 fected. The nose is brought round to the flank, the neck becomes twisted 

 (Wry neck) and death soon takes place. In these cases the wool can be 

 pulled out easily, but fortunately, such severe cases are exceptional. 



After severe attacks recovery is slow, and death often occurs from 

 debility, following upon an attac> 



