882 EXPERIMENT STATION RECORD. 



at Ji moderate expense. As a result of experiments with sheep it was concluded 

 that under some conditions the virus was attenuated in such a way as to suc- 

 cessfully vaccinate healthy ho^'s. but these experiments were suspended since 

 it was found impossible to obtain a definite degree of uniformity or standardi- 

 zation of the sheep-serum vaccine. Experiments witli the donliey, in which 

 more encouraglnfi; results were obtaintnl. were followed by the use of the horse 

 as a medium. 



This work was directed i)articularly toward the production of a horse-.serum 

 hofj-cholera vaccine and not toward the production of a hoji-cholera antitoxin 

 from the horse. The results obt.-iiiied have Ikhmi suniniarized by the author as 

 follows : 



" \'irulent hog-cholera serum exerts a toxic influence upon a healthy horse 

 when injected intravenously. Normal hog-cholera serum or virulent hog- 

 cholera serum does not appear to produce an anaphylactic reaction when in- 

 jected intravenously into the horse. The 2-hour horse serum (drawn from the 

 horse 2 hours after the animal has received, intravenously, approximately 150 

 cc. of hog-cholera virus) w-hen injected subcutaneously into the healthy hog 

 in small quantities produces an acute form of the disease. The 4-hour horse 

 serum when injected into healthy hogs intravenously i)roduces acute hog 

 cholera. The 4-hour horse serum, under certain conditions at least, when 

 injected subcutaneously in small doses into healthy swine does not produce 

 infection. The 5 to 7 hour horse serum when injected subcutaneously into 

 the healthy hog does not produce the disease. The 24-hour horse serum in 

 comparison with 4-hour horse serum, shows attenuated properties. The 24- 

 hour horse-serum vaccine injected subcutaneously and intravenously, and 

 4-hour horse-serum vaccine when injected in small quantities subcutaneously, 

 act as preventives against hog cholera. The 24-hour horse serum, however, is 

 not constant in respect to its protective properties. A rough estimate shows 

 that horse-serum vaccine can be prepared at a relatively low cost. 



" A'irulent hog-cholera serum in the liquid form becomes attenuated after 

 a period of 9 months when kept at a temperature of approximately 10 to 15° 

 C. Virulent hog-cholera serum dried under aseptic conditions at a tempera- 

 ture of 37° becomes attenuated after a period of 8 months. Horse-serum 

 vaccine retains its protective properties for at least a period of 6 weeks when 

 kept at an api)roximate temperature of 10 to 15"." 



It is stated that experiments have shown that a hog once immunized to the 

 disease will retain the protection for a period of from 3 to S months, or long 

 enough to fatten and jirepare the animal for market. 



Tests of Bruschettini's hog'-cholera vaccine and Bruschettini's hog 

 cholera and swine plague serum, James Wilson (U. S. Dcpt Agr., Office 8cc. 

 Cire. 27, pp. 2). — In conformity with provisions made by Congress for the 

 testing of samples of tuberculin, serums, antitoxin, and analogous products 

 bought in the open market, tests were made of Bruschettini's hog-cholera 

 vaccine and Bruschettini's hog cholera and swine plague serum. The results 

 obtained indicate that neither are reliable agents for protecting hogs from hog 

 cholera. 



The dog in health, accident, and disease, F. T. Barton (Philadelphid, 

 [1908], pp. 197, pis. 12). — A popular work largely devoted to a discussion of the 

 characteristics of the various breeds of dogs, but also briefly considering the 

 accidents and diseases to which dogs are subject. 



Experimental studies of acute ankylostomiasis in dogs, J. Cvu.i.t. {Rev. 

 Vet. [Touluuiie], 33 (1908), No. 10, pp. 613-U18, fig. i).— Studies were made of 



