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Cattle of any age can be infeeted with red-water, but wbereas the disease 

 is generally severe and frequently fatal In adults or animals over two years 

 of age, it is so mild a character in calves or animals under a year old that 

 it generally fails to excite in them any visible disturbance of health. As one 

 attack of the disease tends to render an animal insusceiatible, cattle which are 

 infected during early life rarely afterwards become visibly affected or die, 

 even though they are grazed on notoriously dangerous ground. Nevertheless, 

 these animals are not entirely free from the disease, for the rule is that when 

 once an animal has been infected it ever afterwards, or at any rate for years, 

 continues to harbour the minute parasites which are the cause of red-water. 

 This may in mo.st cases be readily proved by using a small quantity of their 

 blood for the inoculation of a healthy adult ox, the almost invariable result 

 being that the Inoculated animal develops the symptoms of red-water after 

 about one week. On what may be called red-water pasture, the animals which 

 were infected while young tend to perpetuate the disease, for ticks, in sucking 

 their blood, become infected and pass the parasites on to other animals on 

 the same pasture. 



The.se facts give the clue to the prevention of the disease. If ticks could 

 be eradicated from any given pasture, red-water would thereby be stamped 

 out, but in actual circumstances such eradication is usually difficult. It may, 

 however, be achieved by Ivceplng cattle and other animals off the pasture for 

 one whole year, as this probably exceeds the greatest possible lifetime of a 

 tick which is denied the opportunity to suck the blood of an animal For- 

 tunately, however, there is a .simpler and less expensive method of, so to 

 speak, cleansing a pasture, and that is to graze it exclusively with horses or 

 sheep for a full jieriod of one year. Such a procedure does not lead to the 

 extermination of the ticks, for these may maintain their existence and propa- 

 gate their species on horses and sheep, but as only cattle can be infected with 

 red-water, an infective tick ceases to be dangerous after it has attached itself 

 to a sheep or horse. It is to be hoiked that in this country attempts will soon 

 be systematically made to stamp out red-water by taking advantage of the 

 facts just mentioned. It must be noted, however, that an essential part of this 

 plan is that after the full .year has been allowed for the cleansing of the ticks, 

 no animal of the ox species that has had an attack of red-water, or which has 

 even been grazed on red-water ground, must be allowed on the purified pasture, 

 because, as already explained, such animals often for life contain the germs 

 of the disease in their blood, and would, therefore, provide the means for re- 

 infecting the ticks. 



Although the measures here advised can scarcely anywhere be altogether 

 impracticable, it is obvious enough that iu general a certain amount of loss 

 and inconvenience would be caused in carrying them out, and it may. therefore, 

 be asked whether there is any other means by which a farmer may prevent 

 or reduce the loss which he annually suffers from red-water. That there is 

 another method in reality follows from what has already been said, for it has 

 previously been explained that the disease, when contracted in youth, is 

 usually so mild as to be of little consequence to the animal, and yet protects 

 it for the rest of its life. Hence, where the more radical measures sketched 

 above cannot be put into operation, a farmer may seek to minimise his losses 



