138 AGRICULTURAL RESEARCH AND THE FARMER : 



In cases in which it has been found that the bacillus was 

 responsible for the disease, serum has been supphed for the 

 mares that were still carrying their foals, and favourable reports 

 of the treatment have been received. During 1920 and 192 1 the 

 Institute has dealt with a considerable number of cases of actual 

 outbreaks of abortion in mares, and has endeavoured to give the 

 widest publicity to breeders of Thoroughbred, Shire, and other 

 horses that the disease is being investigated. A request that 

 the occurrence of cases should be notified to the Institute has 

 been v,idely circulated. The object of the continued investigation 

 is not only to assist individual breeders to deal successfully 

 with outbreaks when they occur, but also to obtain information 

 sho\\dng to what extent the disease prevails in this country. 



In aU cases in which the disease is proved to be of the con- 

 tagious character an endeavour is made to trace its origin in 

 the particular stud. It has to be admitted that up to the present 

 time this effort has in many cases been unsuccessful, mainly be- 

 cause aU the particulars necessary to giiide to a conclusion were 

 not forthcoming. The experience of the Institute would indicate 

 that contagious equine abortion is not yet a very common 

 disease in this country, and that it is in fact rare except among 

 thoroughbred horses. There is no doubt, however, that in 

 certain circumstances it might soon assume alarming proportions, 

 and it is greatly to be desired that breeders of aU classes of 

 horses should take advantage of the assistance v/hich the Institute 

 offers when an outbreak is notified. 



Although what has been learned during recent years marks 

 real progress, much still remains uncertain with regard to a 

 number of important points. The question of the role of the 

 stallion in the propagation of the disease is a little uncertain, 

 but the facts in the possession of the Institute indicate that the 

 disease is seldom or never spread in that way. Another point 

 about which further information is required is the duration of 

 the disease in the mare after abortion has occurred, that is to 

 say, the length of time for which such a mare may be capable 

 of spreading the disease. As is now weU known, this is often a 

 long period in the case of epizootic abortion in cows, but the 

 facts so far collected by the Institute encourage the belief that 

 the recovery of mares is much more prompt. 



Contagious inflammation of the udder, or Mastitis, in corns. 

 — Inflammation of the udder, or what is commorJy caUed 

 " garget," is a very common condition in cows. In almost every 

 herd of moderate size it is possible to find evidence of udder disease 



