334 CONTAGIOUS DISEASES. 



tubercular nodules in the dermoid structures, invading the whole 

 surface of the body. 



Causes. — The ingestion of tubercular growths, or of tubercular 

 milk. A tuberculous mother has, within my own knowledge, 

 transmitted the disease to her offspring, and in some red Tam- 

 worth pigs of my own this was remarkably exemplified. A preg- 

 nant sow was sent to me from a celebrated breeder. In course of 

 time she produced a litter, of which the majority did well, but 

 shortly after the young pigs were weaned the sow became 

 rapidly emaciated and was slaughtered ; on post mortem she was 

 found to have tuberculosis in an advanced stage, involvin<:r most 

 of the organs. 



One boar and one sow of this litter were kept, and after the 

 sow became pregnant the boar was sold and not heard of again ; 

 the sow, a very large fine one, gave birth to eight or nine pigs, and 

 shortly afterwards commenced to lose condition very rapidly. 

 An erythematous eruption appeared on the skin, and under the red 

 spots hard nodules soon began to form ; the young pigs throve 

 for a short time, when some began to fall off rapidly and died 

 tuberculous ; the remaining apparently healthy ones were tested 

 with tuberculin, and all reacted, and some time afterwards verified 

 the value of the test, presenting signs of the eruption upon and 

 nodules within the skin ; rapid emaciation followed, and general- 

 ised tuberculosis was found in all. No cough was observed in 

 these cases ; the appetite remained fairly good for a time, it then 

 became capricious, and signs of indigestion became apparent, with 

 constipation or diarrhoea. Pallor of mucous membranes, the 

 tongue, oral cavity, and conjunctivae, as well as of the nose, was a 

 prominent symptom in all the cases ; the skin, in addition to 

 the eruption, became very dirty, and the animals soon became 

 miserable objects, with sunken eyes and pendant belly. 



The tuberculin test is the most reliable means of diagnosis, 

 for in the absence of obvious symptoms of tuberculosis its 

 detection becomes otherwise a matter of some difficulty. 



T'lihcrculosis is seldom seen in the sheep or goat, but under 

 certain conditions these animals are found not to be immune. 

 Experimentally the disease has been transmitted, particularly 

 by intravenous injection, which sets up an acute, generalised, 

 miliary tuberculosis of a rapidly fatal type, and it is thought 

 that prolonged cohabitation with tuberculous cattle gives tlie 

 disease to both the sheep and the goat, although they, as a nde, 



