58 SEPTICEMIA IN CHICKENS 



§ 40. Geographical distribution. The only locality 

 from which it has been described is lyoudoun Co., Va. It 

 was observed and a few cases studied by Moore and Mack in 

 an epizootic among fowls in the northern part of New York in 



1905. 



§ 41. Etiology. This disease is stated to be due to a 

 streptococcus which grows in short or longer chains with seg- 

 ments varying from 0.6 to o.Spi in diameter. In some cases 

 elongated forms are observed. It is an aerobe, and a faculta- 

 tive anserobe. When cultivated on artificial media it does not 

 liquefy gelatin, it does not change the appearance of milk, but 

 causes slight acidity and thickening of the lower stratum with- 

 out coagulation of the casein. The reaction of alkaline bouillon 

 is changed to an acid one. It does not give a visible growth 

 on potato. It stains by Gram's and Gram-Weigert's methods. 

 In bouillon it grows in somewhat flaky masses while the 

 medium remains clear. It was fatal to fowls, mice, rabbits 

 and swine ; guinea pigs, dogs and sheep were not destroyed 

 by inoculation. This organism has not been specifically named. 



§ 42. Symptoms. It is not at all uncommon to find the 

 fowls dead and lying under the roosts. Occasionally capons 

 were observed to be sick for from 12 to 24 hours prior to 

 death. In these cases the feathers become ruffled and the fowl 

 showed evidence of extreme depression. The onset of the 

 disease is very sudden and its course a very rapid one, usually 

 terminating in death. 



§ 43. Morbid anatomy. The authors describe the 

 morbid anatomy as follows : ' ' The spleen is more or less en- 

 larged, showing hyperplasia of the Malpighian corpuscles. The 

 pulp contains numerous areas of extravasated blood. When a 

 stained section is examined by means of a hand lens a number 

 of circular semi-transparent foci, the size of a pin hole, may 

 be noted. These are found on microscopic examination to be 

 centers of necrobiosis, consisting of parenchyma which has 

 undergone coagulation necrosis, and surrounded by a more or 



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