822 



Dourine. 



nuclei, however, are increased. The cellular infiltration extends also to the sensory 

 roots of the entering zone of implantation, while the degeneration of some of the 

 nerve fibers may be followed into the posterior trunks of the spinal cord, and up to 

 the nuclei of the medulla. The other trunk, as well as in general also the nerve 

 cells, are intact in the spinal cord, as well as in the medulla, otherwise, however, the 

 chronic cases which have been examined manifested no changes, with the exception 

 of some perivascular, inflammatory foci in the gray substance of the spinal cord. 

 This, however, does not exclude the occurrence of intensive inflammatory changes 

 in other cases. 



A fatty degeneration of the muscle fibers, also perivascular cellular infiltra- 

 tion of the intramuscular connective tissue, the intensity of which varies in different 

 parts of the body, is present in the muscles. It is most pronounced in the muscles 

 of the croup and the posterior extremities (Fig. 143). Marek failed to find spe- 

 cial changes either in the corium, or in the subcutaneous connective tissue, corre- 

 sponding with the location of the dollar spots, whereas he met a focal cellular 

 infiltration under the mucous membrane of the vagina, even in chronic cases. 



A. 





Fig. 143. Transverse section through the N. cruralis of a horse affected with dou- 

 rine. a pronounced, 6 slight absence of nerve fibres ; C distended nerve sheath ; d 

 and e epineural cell infiltration. (Marek. ) 



Symptoms. In the appearance of the symptoms two stages 

 must be distingaiished, for which essentially different symptoms 

 are characteristic, and which moreover are separated from each 

 other by shorter or longer, apparently normal periods. The 

 symptoms of the first stage affect principally the genital organs 

 and differ from each other according to the sex of the animals, 

 Avhile in the second stage the symptoms predominate which 

 point to an affection of the nervous system and which are not 

 influenced by the sex of the patient. 



The characteristic sjinptoms of the first stage develop sub- 

 sequently to the infectious coitus, after an incubation of from 

 5 to 6 days up to one montli, sometimes however apparently 

 after several months, as in some cases the disease is manifested 

 only l)y moderate febrile attacks which may be unnoticed. 



