IOI4 Veterinary Obstetrics 



along with the general purulent infection, there ma}' also occur 

 a tetanus infection, inducing a virulent form of that malady. 

 Nocard and others have shown that, in calves, along with other 

 infections, or without them, there may enter through the broken 

 navel cord the germs of infectious diarrhea. One organism or 

 another may acquire precedence, and consequently modify the 

 symptoms of the infection. 



The force of the infection is sometimes expended upon the 

 navel and its immediate neighborhood, producing a type of dis- 

 ease depending somewhat upon its virulence. In such cases 

 it appears that a sufficiently resistant embolus forms in the um- 

 bilic vein to constitute an efficient barrier against the centripetal 

 progress of the infection and limit its ravages to the umbilic 

 region. The infection induces a more or less severe inflamma- 

 tion, with swelling, suppuration, and the formation of abscesses 

 and fistulae. If the infection possesses a still higher virulence, 

 gangrene or necrosis of the tissues may occur. 



If the infection extends beyond the immediate area of the 

 navel through the lumen of the umbilic vein or other umbilic 

 vessels, it quickly gains entrance to the general system, and 

 induces septicaemia or pyaemia. Upon post-mortem examina- 

 tion in such cases, the navel vein is usually found filled with 

 decomposed blood, mixed with a dirty-gray, flocculent pus. 



The umbilic vein is converted into a vast suppurating tube, 

 opening at one end into the hepatic vein, at the other externally 

 at the umbilicus. The purulent contents may escape outwards 

 through the navel or inwards into the hepatic circulation. Once 

 the infection reaches the hepatic circulation, it flows freely to 

 the heart, passes through the pulmonary system and gains the 

 systemic circulation. The gravity of the attack is dependent 

 upon the amount and virulence of the infection entering the 

 hepatic circulation, and the power of resistance (age and vigor) 

 of the patient. In many cases the septicaemia is so acute and 

 intense that the patient succumbs in a few hours, pre.senting 

 essentially only the symptoms of high fever with very slight 

 navel disease. 



In other instances the disease assumes the character of 

 pyaemia, and the clumps of bacteria, passing into the general 

 circulation, are forced through the pulmonary vessels, into the 

 lungs, where they may lodge to bring about pulmonary abscesses. 



