342 Agricultural Gazette of N.S.W. [May 3, 1920. 



will be found to exist. Only one disease can be so easily guarded against as 

 strangles and influenza, and that is pleuropneumonia contagiosa. An 

 isolation period of thirty days would in most cases warrant one in taking it 

 for granted that the cattle were free, unless there was amongst them some 

 beast with a chronic lesion in the lung, and in such a case it would not be 

 possible to say at what period (if ever) the animal could lie considered safe. 

 Care in seleciing the district in which cattle are purchased goes a long way 

 to safeguard a farmer, and, again, if the animals ai-e purchased direct from 

 the farm there is less likelihood of infection. 8uch acute diseases can usually 

 be guarded against with success, but the chronic ones — such as tuberculosis 

 — pi'esent a more difficult problem. 



It may safely be said that no or-dihary inspection, without resort to tests, 

 can pn^vent the introduction of tuberculosis into a herd. Nevertheless, if 

 it is carried out by trained men it may do something to reduce the number 

 of tubercular animals introduced, and if the tuberculin test be applied by 

 men skilled in its use, a herd could be kept free from the disease. The 

 expense involved in testing, and the difficulty in country districts of pro- 

 curing the services of men capable of properly carrying it out, will generally 

 act as deterrents to its application. 



In dealing with tuberculosis, it is not of great value to keep newly 

 introduced cattle in isolation, because in many instances an animal may be 

 affected for a very long period without showing any outward symptom. The 

 intending purchaser should have as efficient an inspection made as it is 

 possible to get, should buy from farms with a reputation for health (and in 

 most districts it is possible to get some idea of the reputation of breeders 

 from this point of view), and at the first sign of suspicions of tuberculosis 

 should get a veterinarian to inspect. It must be borne in mind that a 

 tubercular animal may at any time become infectious, and that it is then 

 dangerous to other cattle and pigs, and, if a milking cow, to human beings as 

 well, and particularly to the young of all three. 



Much the same may be said with regard to actinomycosis so far as 

 prevention goes, but of course the danger and infectivity are far less, and so 

 long as there are no open discharging areas the disease is not of much 

 importance. 



Both contagious manmiitis and contagious abortion (especially the latter) 

 are common in the State, and the isolation of newly-purchased cows is 

 strongly recommended in respect of these diseases. In so far as mammitis 

 is concerned the isolation need only be for a few days, until it can be 

 noted that the udder and milk supply are noi-mal. This must involve, in 

 the case of milking cows, careful manual examination of the udder and a 

 visual examinaticm of the milk. Cows with irregularities in the udder should 

 be looked upon with great suspicion, as such irregularities might be due to 

 tuberculosis, actitiomycosis, or one of the various forms of contagious 

 mammitis, and no cow so affected should be permitted with the herd. 

 Contagious abortion will require more care, and it would be just as well, if 



