Septicmmia Hcemorrhagica of the Sheep. 65 



those on poor feeding and perhaps nursing twins, those that have 

 suffered from any debilitating disease of any kind are especially 

 obnoxious to a dangerous attack. 



Microbiology. The microbe, which I<ignieres found in the 

 pulmonary lesions, is one of the colon group of pathogenic bac- 

 teria that have been classed together as pasteurella. It usually 

 appears as a very minute ovoid bacillus which stains promptly 

 and deeply at the poles in fuchsine or gentian violet, leaving a 

 clear median part, so that it seems a diplococcus . It bleaches 

 readily in Gram's solution. Its form varies in different culture 

 media sometimes showing long bacilli, and sometimes strepto- 

 cocco- bacilli, but the usual and characteristic appearance is that of 

 a cocco-badllus , and to this it constantly returns. The microbe is 

 aerobic and nonmotile (the slow zig-zag motion sometimes seen 

 does not seem to be automatic) . In peptonised bouillon it produces 

 opacity in 18 hours, or in simple bouillon in 24 to 48 hours, the best 

 temperature being 100° F. Gelatine plate cultures are slow 

 because of the compulsory low temperature, yet in 36 to 48 hours 

 it forms pale blue, translucent, round colonies the size of a pin 

 head. It never liquefies. In coagulated blood serum it forms 

 only a thin transparent pellicle hardly visible, and there is no 

 growth on potato. 



Symptoms: Chronic Form. In Argentina, ]l,ignieres observed 

 the disease especially during the hot summer months (December 

 to May), and after weaning in the lambs. This may be from the 

 marked change of food, from the greater activity of microbian 

 life at this season, from the exhausting effect of the heat, or 

 from a combination of two or more of these conditions. It 

 appears alike in the sheepfold, and on the open prairie. 

 In considerable flocks the symptoms may be at first over- 

 looked, so that the death of several .sheep may be the first 

 thing to draw attention. Then a certain number are found to 

 scour, arch the back, walk stifHy, lose condition, and have the 

 wool flattened and devoid of yolk {clapped wool). The sheep 

 may be dull, lagging behind its fellows, or lying apart by itself, 

 ruminating infrequently and for shorter periods than natural, and 

 there maybe inappetence, or depraved appetite (eating earth), 

 though some eat well to the end. Irregular and at intervals capri- 

 cious appetite is a frequent condition. When caught and exam- 



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