X20 Hemorrhagic Septicemia of Sheep. 



and finally die with, symptoms of enteritis, diarrhea and anemia. 

 The same results may also be obtained by repeated injections 

 of one-third to one-half cc. of a fresh, virulent culture as well 

 as by intravenous injections of 5 to 10 cc. of an older culture 

 (Lignieres). The infection may also be produced with, ground 

 lymph glands and should the animals remain alive for a longer 

 time certain parts of the lungs become hepatized, and as in the 

 acute cases the lymph glands are markedly swollen (Miessner 

 & Schern). By feeding 50 to 60 cc. of culture Lignieres pro- 

 duced the disease in sheep, although the attack was only slight. 

 On the other hand similar experiments by Miessner & Schern 

 with. 150 cc. of culture gave negative results. Inhalation of 50 

 cc. of culture killed a lamb in three days. 



In animals which died from the acute form of the disease 

 the bipolar bacilli may be found in all the organs, while in 

 the chronic cases they are frequently absent and other bacteria 

 may be demonstrated in the affected tissues. Mice, guinea pigs 

 and rabbits can be easily infected while birds are more resist- 

 ant. In large animals the subcutaneous injection of the virus 

 produced a serous inflammation at the point of infection. Intra- 

 venous injections (50 to 100 cc.) cause the death of the animals 

 from septicemia within a short time (Lignieres). The chronic 

 form of the disease could not be produced artificially. 



Natural infection occurs very likely through the digestive 

 tract as a result of the ingestion of infected food or drinking 

 water on infected pastures or in contaminated stables. Young 

 sheep are particularly susceptible immediately after weaning, 

 and the disease usually runs a rapid course in these animals, 

 while in older animals it is more likely to take on a chronic 

 character. 



Infectious excrements and excretions of affected anjmals 

 naturally add substantially to the dissemination of the disease. 

 In herds which are kept in a small pasture or in stables the 

 disease usually occurs in a more severe form. Affected animals 

 may spread the disease to healthy herds. 



External influences which reduce the natural resistance of 

 the animals, such as continued cold and exposure to rain, etc., 

 increase the susceptibility, and therefore the disease usually 

 occurs after damp weather and in general in marshy localities. 



Furthermore, according to Lignieres' view, thread worms 

 (strongylides) favor the infection through injuries of the 

 mucous membrane of the stomach and intestines thereby render- 

 ing possible the entrance of the bipolar bacilli, which are pres- 

 ent in the feces or in the mucous secretions of the air passages, 

 into the lymph spaces of the mucous membrane (according to 

 Besnoit & Cuille the dystomas in the bile ducts exert a similar 

 action). 



Lignieres' view on the close connection of the bacterial infection with the 

 lung and intestinal worms must be considered as too far fetched, Admitting that 



