EXPERIMENT STATION REPORTS. 155 



and now manager of a large dairy farm near Ann Arbor, this past year 

 has given our laboratory the privilege of working out certain bacteri- 

 ological problems concerning pure milk in connection with milk pro- 

 duced under varied conditions on his farm. Much valuable data have 

 been obtained and will be compiled later." 



PATHOGENIC BACTERIOLOGY. 



The agglutination work of Dr. Giltner's which has been conducted here 

 for two or three years past in connection with the Dorset-Niles serum 

 production has been completed, and the results appear elsewhere in 

 this report, as Technical Bulletin No. 8. 



Contagious Abortion. — This disease is now receiving special attention 

 from Dr Giltner. The following general remarks from him may be of 

 interest at this time: 



"The work with infectious abortion of cattle progressed very slowly 

 until recently. We have succeeded in isolating in ])ure culture from 

 the exudate and cotyledons of an aborting cow the bacterium described 

 by Bang, McFadyean, MacNeal and others as occurring in epizootic 

 abortion. The cultural as well as morphological characters of this or- 

 ganism have been well described in the literature and need no repetition 

 here. In the case from which we secured our pure culture we were also 

 fortunate in securing material in the shape of a fetal cotyledon and a 

 fetal and maternal cotyledon attached, sections of which stained in 

 hematoxylin and eosiu show characteristic clumps of the Bact. abortus. 

 Immunization experiments have been started with guinea pigs and 

 heifers, but a report of this work should be delayed. 



The treatment of abortion in practice is receiving attention and cer- 

 tainly demands it if we may judge from the reports of the disease 

 that come to us. The posl:-abortion treatment of cows, in order to 

 eliminate the organisms from the genital organs and passages and pre- 

 vent their spread, is a serious and difficult matter. Disinfection of the 

 uterine or even vaginal mucosa is impossible by the use of any disin- 

 fectants in solutions weak enough to insure against injury to these 

 tissues. In your report of the preceding year is given an account of 

 the use of lactic cultures in this connection. In this year's work we 

 have used the ordinary lactic organisms and Bact. bulgaricum in whey 

 cultures. At your suggestion, we have also used the whey recovered from 

 milk curdled by these organisms. As to the relative merits df these 

 methods, we may say that whey is superior to lactose broth as a medium 

 for these organisms and that a much higher (two or three times) degree 

 of acid is secured by employing the whey from milk curdled by these 

 organisms, but this higher degree of acidity is objectionable in view 

 of the fact that it terminates the existence of the lactic organisms. 



The aim of these operations is to establish a lactic flora on the genital 

 mucosa with the result that the abortion bacteria and other objectionable 

 bacteria will be overcome and not pennitted to reappear. It is true that 

 this is merely a hypothesis, but a very reasonable one, and is fortified 

 by favorable clinical experience. \\e have approached the subject from 

 the experimental standpoint in the following manner: A study of the 

 normal and abnormal (under conditions of abortion and sequelae) flora 

 of the genital passages has been instituted. This is to be followed 



