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sheep drink. Dry pastures without bog-holes or sloughs are best for 

 the animals. As the germs live for some time in a dried condition the 

 old pastures should not be used for young sheep at least, nor should 

 the latter be allowed to graze after older sheep which have had the dis- 

 ease during the previous year, nor should the pasture be overstocked 

 so that the grass is eaten to its roots. 



Disease. — Verminous bronchitis attacks young animals, those under 

 two years being the more susceptible. Animals poorly nourished and 

 those already weak from other parasitic diseases are also more liable to 

 become a prey to this worn. Damp, warm seasons are most favorable 

 for the preservation of the parasite and the disease it produces. The 

 disease is most prevalent in summer and autumn, becomes less in 

 winter, and disappears in spring time. 



The symptoms of this disease, as in verminous pneumonia, are im- 

 perceptible in the first stages. It is probable that, beyond the slight 

 but deep cough produced in some of the worst cases, but little else can 

 be noticed. The sheep may have ditficulty in breathing when driven 

 or be short-winded. They may be antemic, as shown by the harsh, dry 

 skin, dry wool, and pale mucous membranes. In later- stages the 

 symi)toms will be aggravated; difficulty in breathing, coughing, and 

 general debility, associated with an antemic condition, will be the most 

 prominent symptoms. Occasionally shreddy masses will be coughed 

 up, which, on close examination, will prove to be worms. This is a 

 decisive test of the nature of the disease. 



The sheep has a fair appetite, but will gradually lose flesh. In the 

 last stages the bronchial cartarrh is severe, the respiration very feeble 

 and jerky, the cough deep, convulsive, and evidently painful, coming 

 by fits and followed by suffocation, which leaves the patient still more 

 exhausted. The nasal discharge becomes more copious, and contains 

 quantities of embryo and worm fragments. Owing to the diminished 

 respiration productive of anaemia, the skin becomes dry and harsh, and 

 resembles parchment ; hence the popular name " paper-skin." The wool 

 is also affected and is easily pulled off, exposing the white, bloodless 

 *skin underneath. 



Duration. — Death occurs in three or four months either by exhaus- 

 tion of vital forces or by sufitbcation. As the first stages pass unnoticed 

 the total time from infection to death is probably nearer five or six 

 months. The duration of the disease depends on the amount of infec- 

 tion, the previous health of the patient, the care it receives, and its vi- 

 tality. Where the symptoms are very decided the patients rarely sur- 

 vive. The disease is most intense in autumn, and if the sheep do not 

 die, it becomes less intense in winter to more or less completely disap- 

 pear in spring. When the season has favored the development of the 

 disease and the lambs show severe symptoms, the outlook for their re- 

 covery is very unfavorable. A large percentage of those attacked die. 



