314 CONSTITUTIONAL DISEASES 



seems to show the greatest number of cases, still young animals are 

 frequently attacked, and the disease invariably runs an acute course. 

 It is apt to follow certain traumatisms, but whether, in dogs, it follows 

 as a result of grave infectious disease is a question. Attempts to produce 

 the disease by transfusion of leukaemic blood in healthy animals gave 

 negative results but produced a swelling of the gians penis and the 

 lymphatic glands in its immediate neighborhood, and catarrh of the 

 prepuce. 



Pathological Anatomy. — The most important alteration always 

 observed in this disease is an increase of white blood corpuscles and a 

 lessening of the amount of the red corpuscles in the blood. This may 

 become so great in the dog that we find the proportion of white to red 

 blood corpuscles is 1 to 5 (Bollinger). "We find the blood possesses a 

 much lighter color than it does normally, has a lighter specific gravity. 

 We also notice a great tendency to emaciation and a characteristic 

 alteration of the spleen, which is greatly enlarged, and increased pro- 

 portionately in weight. It is not rare to find it weighing at least 1000 

 grammes, and we find on section of the enlarged spleen, marks of 

 true hyperplasia. Fenereissen found in a bulldog affected with this 

 disease a spleen that weighed 3 kilogrammes. We also see at times 

 enlargement of the lymphatic glands due to circumscribed hyperplasia 

 of the glandular tissues. The marrow of the bones is occasionally 

 involved and appears dark red. In serious cases the color is yellowish- 

 gray, becoming soft and plastic. In very rare 

 cases hyperplasia is seen in other organs, such as 

 the tonsils, liver, and lungs. 



Clinical Symptoms and Course. — The symp- 

 toms of the disease are similar to those of intense 

 anaemia. First, there is a characteristic alteration 

 of the blood, and, second, the symptoms presented 

 by the spleen and lymphatic glands. In mild 

 Fig. 101.— The blood in cases a microscopic examination of the l^lood and 



leukocythaemia. . <■ i i i mi • 



counting the number of blood corpuscles will insure 

 a diagnosis. The best way to obtain a small quantity of blood for the 

 purpose of making an examination is to make a slight slit in the upper 

 surface of the outside of the ear. Place it under the microscope without 

 adding any other substance to it, and we will recognize not only an 

 enormous increase in the number of white blood corpuscles, but a differ- 

 ence in their normal size (Fig. 101). 



While we may be able to correctly diagnose the disease from the 

 condition of the blood during life, we may also notice certain alterations 

 in the size of the spleen and lymphatic glands. In the glands of the" 

 head and neck we frequently find considerable enlargement. Normally, 



