INFECTIOUS DISEASES 33 



STRANGLES 



§ 21. Characterization. ^Strangles is an infectious dis- 

 ease of horses, asses and their hybrids occurring sporadically 

 and in epizootics. It is characterized principally by a fever, 

 followed by an acute catarrh of the mucosa of the upper air 

 passages especially of the nares, and a suppurative inflamma- 

 tion of the lymph glands of the submaxillary and pharyngeal 

 regions. The lesions, however, are not restricted to these 

 parts. It is a disease of 3'oung animals. 



§22. History. Strangles was among the first equine dis- 

 eases to be recognized. In 1664, vSolleysel gives an account of 

 it and points to the fact that it had been known for a long 

 time. Its infectious (contagious) nature was determined ex- 

 perimentally in 1790 by Lafosse and since that time by a num- 

 ber of other investigators. In 1873, Rivolta found in the pus 

 of the abscesses a micrococcus which appeared in chains of 

 from three to five segments. Baruchello, in 1887, described 

 as its cause an organism, which he designated as Bacillus 

 adenitis equi. Strangles has been thought by some, to be 

 identical with scrofula and measles. Sacco and Na.sbot consid- 

 ered it as horse pox. Viborg and Toggia and more recently 

 Nasbot advocated the inoculation of horses with the lymph of 

 horse pox as a prophylactic measure against strangles. Dela- 

 motte demonstrated that this procedure was of little or no pre- 

 ventive value. The supposed specific cause {Streptococcus 

 equi) of strangles was described first by Schiitz and later by 

 Sand and Jensen in the same year (1888). The discovery has 

 been confirmed by Poels, L,upka, and others. More recently 

 Lignieries has discovered a "coccobacillus" which he believes 

 to be the primary cause. He considers the streptococcus of 

 Schiitz as a secondary invader of no specific value. 



§23. Geographical distribution. Strangles is a wide 

 spread disease among horses. It appears to stand in equine 

 pathology very much as measles do in human medicine^a 

 disease of early life and consequently more prevalent where 

 there are more young. It seems to exist in all countries 

 where the horse kind are raised and to be more prevalent in 

 breeding districts than elsewhere. 



