TETANUS 309 



3 to 5 per cent, of haemoglobin. The blood is thin, light red, and coagulates 

 very slowly; the number of erythrocytes is diminished by half, 

 and the leukocytes are greatly increased in number. Death occurs in 

 from three to ten days. 



In the chronic form the temperature is slightly increased or may even 

 remain normal, the animal shows great muscular weakness, lassitude, 

 want of appetite and rapid emaciation, urine contains albumin and 

 biliary pigment, while haemoglobin is rarely found, and there is a diminu- 

 tion of the red blood corpuscles and a corresponding increase of the white 

 corpuscles. The duration of this disease is from three to six weeks; 

 recovery is not at all rare. The diagnosis is easily ascertained by the 

 presence of the piroplasma in the blood. Nocard suggests that where 

 there is every evidence of the disease, but microscopical examination 

 fails to detect the piroplasma, a young animal should be inoculated 

 experimentally. 



Therapeutics. — As there is no specific agent that can be said to 

 have any beneficial effect on the disease, we must give good nursing, 

 careful but nutritious diet. When animals, particularly hunting dogs, 

 are taken to regions infested with ticks, such as woods, wet swampy 

 ground, or low scrub pasture, the animals should be rubbed with emul- 

 sions of lysol, creolin or petroleum to protect them from invasions of the 

 tick. 



Preventive Inoculation. — When a dog has overcome the disease 

 and become immune, the l^lood of this animal possesses the property 

 of destroying the piroplasma; these immune animals are inoculated 

 repeatedly with the virulent blood, and a serum is obtained w^hich is 

 used. Care must be taken to see that this serum retains its activity. 



Tetanus. 



(Lockiaw.) 



This is a specific infectious disease characterized by tonic muscular 

 contractions and caused by the tetanus bacilli. These organisms are 

 rather long, slender — from two to four microns long — with a globular spore 

 at the end; this is larger than the bacillus and gives the latter a drumstick 

 shape. The organism is strictly an anaerobe and is obtained in pure cul- 

 ture with some difficulty; morphologically it is difficult to distinguish from 

 the bacilli of malignant oedema and systematic oedema (Ricketts) . These 

 spores possess great powers of resistance and are found in soil, particularly 

 in garden earth and rich meadows, and in the excrement of healthy 

 horses, dogs, cattle and other animals; this explains why animals are 

 so, prone to develop the disease from wounds of the extremities, tail, etc. 



