530 Journal of the Departmein't or Agriculture. — Dec, 1^22. 



The lesiilts of t]ie j)iesc'iit expeiiiiients upon cattle have been 

 so stri]\in<;' that the nutritioua! factors involved are being explored 

 in all directions, ajid considered especially in rej^ard to sheep and 

 horses. 



From the strictly disease point of view, the earlier work is being 

 continued upon the conditions of toxin production, the distribution 

 of the toxicogenic sapi'ophyte throughout the Union, the study of 

 putrefactive bacteria, and similar problems; although shortage of staff 

 necessitates subdued activity in such directions. 



Pica Surrey. — This work, initiated in 1920, has been abandoned 

 as a consequence of the reduction in divisional expenditure. The 

 data already acquired are, however, of considerable value, and indi- 

 cate the necessity of continuance the moment finances permit. The 

 results will bear not only upon the control of lamsiekte, but directly 

 upon the beef-production of the Union. 



Anthrax. — Furiher experiments were undertaken with a view to 

 adjusting the strength of the spore vaccine so lhat it would confer 

 sufficient immunity to stop and prevent an outbreak of the disease, 

 and yet cause no ill effects in the inoculated animals. The results of 

 previous experiments were confirmed ; goats were very much more 

 susceptible than other animals, and it was found advisable to make a 

 special vaccine for use on these animals, which is now being- issued 

 and applied with good results. This same double vaccine is also 

 recommended for milch cows and in other special cases. 



Experiments were also commenced in the Orange Free State with 

 the object of establishing- the role that the horsefly plays in the 

 spread of anthrax. Various observations made it extremely probable 

 that these flies are responsible for many severe uutl-reaks. Unfortu- 

 nately, the experiment had to be discontinued because no further cases 

 appeared on the farm where the work was carried out. It is hoped 

 that conclusive evidence will be obtained during the coming year. 



A number of tests was also conducted with the Australian spore 

 vaccine (McGarvie Smith Institute, Sydney, New vSoutli AVales), 

 reference to which has appeared in the press. These tests confiimed 

 the earlier conclusions that the Australian vaccine was undoubtedly 

 good and produced a very strong immunity. Immediately after vac- 

 cination the animals withstand very large doses of virulent material. 

 In test sheep it was found that the immunity began to decline after 

 six months. The clain) that the vaccine produces life-long immunity 

 could not be substantmted. It was further found that ^he Australian 

 vaccine when inoculated into goats produced a mortality of about 

 20 to 30 per cent. Comparative tests between the Australian and 

 the Onderstepoort spore vaccine showed that the immunity produced 

 is about the same in both, that, however, the Australian vaccine pro- 

 duced worse swellings in horses, and that it is positively dangerous 

 for goats. 



Qvarter Evil. — Fairly successful experiments were carried out 

 to find a reliable vaccine in liquid form. Such a vaccine has been 

 prepared, and the results obtained from the use of several thovisand 

 doses issued free to farmers are ver\ encouraging. Further expeii- 

 ments, having for their ol-ject the improvement of this vaccine, are 



