IN^FECTIOUS DISEASES OF CATTLE. 515 



or inside lining membrane is markedly wrinkled or corrugated, 

 showing large coarse folds with more or less reddening or hemor- 

 rhagic patches or spots on the summits of the ridges, especially notice- 

 able in the large intestines. The mesenteric hmiph glands are usually 

 somewhat enlarged and appear watery on section. The other organs 

 do not appear to be affected except from the anemia present in the 

 later stages of the disease. 



Differential diagnosis. — The principal disease with which bacterial 

 dysentery may be confused is tuberculosis, but the application of the 

 tuberculin test will readily diagnose the latter disease, while no reac- 

 tion will be noted in case the injected animal is suffering with the 

 former affection. The disease may also be mistaken for the parasitic 

 affections resulting from stomach worms (verminous gastritis) and 

 intestinal parasites, especially uncinariasis, but a microscopic exami- 

 nation of the feces is necessarv' in order to establish definitely the 

 diagnosis. 



Treatment. — As with all other forms of infectious disease, it is 

 advisable to separate immediately the diseased and suspected cattle 

 from the healthy animals. The feces passed by the former animals 

 should be placed on cultivated soil where healthy cattle would not 

 be exposed to them, as the bacilli producing the disease are readily 

 found in such manure. The stalls, stables, and barnyards should 

 also be thoroughly disinfected, as has been described under '* Tuber- 

 culosis," in this chapter, special attention being given to those places 

 which have been soiled by feces. The administration of medicines 

 has thus far been quite unsatisfactory, although treatment should be 

 directed toward disinfecting the intestines with intestinal antisep- 

 tics, such as creolin in 2 teaspoonful doses twice daily or tannopin in 

 1 dram doses twice daily, and strengthening the animal by the use 

 of stimulants such as strychnin in half-grain doses given twice daily 

 hypodermically. Salol, turpentine, or subnitrate of bismuth in a 

 starch or wheat-flour gruel may also give temporary relief, but the 

 diarrhea is likely to reappear and cause the death of the animal. In 

 all cases the food must be carefully selected to assure good quality, 

 and should consist preferably of nutritious diT feed. 



Nagana, also called tsetse fly disease, is an infectious fever occur- 

 ring chiefly in horses and cattle, characterized by alternating par- 

 oxysms and intermissions and produced by a specific flagellate proto- 

 zoan {Ty'ypanosoma Brucei) in the blood. It is probably transmitted 

 from animal to animal solely by the bites of the tsetse fly. This 

 insect is something like a large house fly, and when it settles on a 

 diseased animal sucks the blood and infects its proboscis, it is enabled 

 on biting a second animal to infect the latter by direct inoculation. 



