214 COMMON DISEASKS. 



The nasal discharge is thin at first, gradually becoming thicker. 

 Some cases become chronic, and especially vvhen the subjects are 

 weak and unthrifty. The inflammation of the nasal mucous mem- 

 brane may then extend into the head sinuses, and cause extensive 

 collections of pus, and also extend down the mucous membrane 

 lining the trachea. 



Prevention. — First of all. abundant ventilation at all seasons. 

 Sheep are very frequently housed too closely in winter. The in- 

 terior of the building becomes very damp and the conditions in 

 general are unwholesome. Healthy sheep do not need much pro- 

 tection in the winter time, so far as warmth is concerned. If they 

 are well protected from cold rains and snows, and from cold winds 

 they are most thrifty with abundant ventilation. Sheep that are 

 shorn early in the spring need careful management tor a time in 

 order to prevent their catching cold. 



Treatment. — The sick animals must have shelter. Their quar- 

 ters nmst be dry, reasonably warm, and well ventilated. They 

 must be well fed. The medicinal treatment sliould consist mainly 

 of tonics, for instance: a simple, bitter vegetable tonic. like gentian 

 root, which may be given in a powdered form in the feed two or 

 three times daily ; about one dram per sheep. 



