86 EXPEEIMENT STATION RECORD. 



hotli diseases, while at other times it is highly susceptible to their action. The 

 fatal effect of the pathogenic bacteria may. therefore, be prevented in part by 

 drenching the sheep with cultures of these bacteria during the periods of 

 resistance. 



Diseases of swine, R. A. Craig {New York: Oraiif/c Jitdd Co., 19011. pp. IDl, 

 pgs. 23). — In view of the agricultural importance of swine raising the literature 

 relating to swine diseases may l)e considered as too much scattered to be avail- 

 able for practical use by the farmer. The author has attempted in the present 

 volume to bring together the known facts relating to the common diseases of 

 pigs. The sul)ject-inatter is discussed inider a number of heads, including gen- 

 eral, surgical, infectious, and parasitic diseases. Particular attention is given 

 t© a thorough discussion of the serious infectious and parasitic diseases of hogs. 



The hog-cholera group of bacteria, J. Citron (Zt.schr. Ilyo- u. Infections- 

 krank., 53 (19.06), No. 1, pp. 159-115). — In the author's experiments particular 

 attention was given to a study of agglutinins and aggressins and other bacte- 

 rial substances contained in the hog-cholera group. It was found that monova- 

 lent hog-cholera serum agglutinates the organisms of hog cholera, paratyphoid, 

 and mouse typhoid. The most of the bacteria belonging to this group, when 

 studied in vitro, show a very slight absorptive power for antibodies, ^yhile a 

 study of the cultural characters and serum reactions of bacteria of this group 

 indicates a close relationship between the different members, the author never- 

 theless believes that more study must be devoted to the group before it is safe 

 to consider the organisms of hog cholera, mouse typhoid, and paratyphoid as 

 identical. 



Iramunization of hogs against swine plague by means of aggressin, 

 E. Weil (Ccutbl. Bakt. [etc.], 1. AM., OrUj., J,l {1906), No. 1, pp. 121-125).— 

 Attention is called to the difficulties which have been experienced in producing 

 innnunity against the various forms of hemorrhagic septicemia, to which group 

 swine plague belongs. By means of aggressin, however, many of these difficul- 

 ties are overcome, and according to the author's experiments excellent results 

 ;re obtained. It was found in exi)eriments with rabbits that when these ani- 

 mals were inununized against swine plague by a single injection of aggressin 

 obtained from hogs, an innnunity was produced which protected them against 

 inoculation with virulent cultures nearly 5 months later. In experiments 

 with hogs it was found that the aggressin in order to be perfectly effective 

 should come from other hogs rather than from rabbits. When rabbit aggressin 

 was used it appeared that 2 inoculations of 10 cc. were enough to protect the 

 animal against a fatal dose of swine-plague culture. It seems that for a short 

 time after inoculation with aggressin and before this material has become 

 effective, the animals are unusually susceptible to swine plague and more likely 

 to take tlie disease than are those which have not been treated with aggressin. 



Intestinal emphysema of hogs, A. Jaeger (.1/-c7(. ITm-. ;/. Prakt. Tierhcilk., 

 32 {1906), No. 4-5, pp. 410--'f55, pJs. 3).- — Considerable attention has been given 

 to this i>eculiar condition which is quite often met with in bogs, and no 

 specific cause has heretofore been definitely assigned for it. According to the 

 author's investigations, based on a large number of cases and on the bacterio- 

 logical study of the tissues involved, this disease must be considered as a 

 local infection in the small intestines, in which the most important processes 

 take place in the lymphatic vessels. The disease is said to be due to a specific 

 organism referred to as Bacillus coU lyniphaticiis aerogenes. Inoculation 

 experiments were made with the organism in question, as a result of which the 

 characteristic vesicles containing gas developed along the walls of the intes- 

 tines and bacteria were again recovered in pure cultures. 



I 



