Diseases, Ticks, and their Eradication. 159 



Coast fever ticks do' not immediately discliarge the infection after 

 biting-; a short interval is reqiiired. Hence by applying short-interval 

 dipping- as well fnrther outbreaks of the disease can be arrested, and 

 in maintaining the dipping- the ticks will finally be eradicated. 

 Althougli it would be desirable to eradicate all ticks by concerted 

 measures the day is still far off when it will be achieved. Meanwhile 

 it is necessary to draw attention again to one important fact mentioned 

 before. If, for instance, cattle are bred on a non-tick-infected area 

 they will not acquire immunity against redwater and gall-sickness, 

 and when moved into tick-infected areas will contract the disease. 

 The same is the case with biliary fever in horses. Earmers who adopt 

 dipping and who wish to raise immune stock must take this fact into 

 consideration. Hence, under the present conditions of non-com- 

 pulsory dipping they should maintain at least a moderate tick infec- 

 tion just enough to ensure the acquisition of immunity. This difficulty 

 can, in the case of redwater and gall-sickness, be overcome by artificial 

 inoculation of the young* stock against these two diseases. Since this 

 is possible complete tick destruction should be aimed at. 



Saving of cattle from redwater and gall-sickness infection without 

 dipping, once the disease has broken out, is also possible on the lines 

 indicated above for East Coast fever. Since, however, practically the 

 whole of Africa is infected with redwater and gall-sickness such 

 moving is of little use ; the movement merely takes place from one 

 infected area into another one. There are, however, different degrees 

 of infection, hence moving of stock may nevertheless be a practical 

 expedient. 



Eor the eradication of the ear-tick, dipping is of little use. In this 

 case hand-dressing has to be applied when the animals are suffering 

 badly from the infection. This dressing is, however, done previously 

 to relieve the animals ; as a method of eradicating ticks from the 

 farm it would be too cumbersome. Hence the tick should be attacked 

 in a different way, viz., by destroying the hiding-place of the adults, 

 by putting them out of use until all ticks have died out, which may 

 take as long as three years. The erection of bush kraals — which can 

 be destroyed or simple wire kraals which can be removed— would be 

 a simple expedient. Naturally with the shifting of the kraal a 

 cleaning of the ears must take place as well. 



Outlook, 



Tick eradication has now been carried out in South Africa for 

 the last twelve years or more, and yet East Coast fever has not been 

 eradicated on all farms where clipping- was introduced. This is not due 

 to the inefficiency of the dipping method, but to the human factor 

 that interferes with the regular and systematic procedure. Hipping 

 is such a certain remedy for saving cattle that the fear of East Coast 

 fever has greatly disappeared. Indeed the proverbial familiarity 

 with the disease has produced its results. From the point of view of 

 the State this position is not satisfactory; complete eradication of 

 East Coast fever and all other tick-borne diseases is desirable. It 

 would appear, however, that such destruction is frustrated by this 

 human element. The best advice that can be given to a farmer at 

 the present time is to lose no time, but put up a tank and use it, 



