Report on protective inoculation against tick fever : an account of an experimental inquiry into its effect on cattle, and on meat and milk, together with some notes on protective measures other than inoculation / by FrankTidswell.

  • Tidswell, Frank, 1867-1941.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Report on protective inoculation against tick fever : an account of an experimental inquiry into its effect on cattle, and on meat and milk, together with some notes on protective measures other than inoculation / by FrankTidswell. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    19/20 (page 15)
    16 Report on the initiation of proteetive inoculation against Tick Eevcr in the North Coast Districts. Being aware that Dr. l'\ Tidswel!, Principal Assistant Medical Officer lo the Government, is about to furnish a report dealing fully with the nature and effects of protective inoculation against Cattle Tick Fever, it is propo.sed to confine this report to the principles underlying the application of this procedure as now being initiated in the North Coast District. The method adopted has been formulated upon the results of experiments carried out in Sydney and information gathered during the recent visit to Queensland in association with Dr. Tidswell. Protective Inoculation consists of the subcutaneous injection of five cubic centimetres (5 c.c.) of defibrinated blood taken from an immunized or “salted” animal. That is one that has suffered from a severe attack of Tick Fever naturally or artificially acquired. Bepeated expei'iments have proved that the blood from an animal salted by artificial inoculation posse.sses the same protective properties as that from one whose immunity has been naturally acquired. Tue Establishment of Salted Stock. The primary and most important step in initiating inoculation is the establishment of a stock of thoroughly “salted” but otherwise healthy cattle for the sale of blood Healthy young cattle (calves and yearlings) are best adapted for this purpose as they are easier handled and operated on. Moreover they are naturally less susceptible to the virulence of the fever, and are generally constitutionally healthier than adults. Still as tuberculosis affects cattle of all ages, it is sound,practice to subject all intended for this purpose to the tuberculin test. The animals must indis- putably withstand the test. In order to thoroughly “ salt ” these “stock cattle” it is recommended that they receive three inoculations as follows, viz.:—■ (a) A first inoculation of 5 c.c. of recovered blood. This should produce a reaction within four to twelve days, after which a period of four to eight weeks is allowed to elapse for complete recovery to take place. When they are subjected to,— (b) A second inoculation of 10 c.c. of recovered blood. This inoculation is not considered indispensible in cases wBere the temperature records of animals taken after the first inoculation indicate that a severe reaction has taken place. It is however, recommended to be practised when large numbers are operated on at the one time. After this inoculation the cattle are kept under observation for fourteen days, and if no reaction follows,— (c) A final inoculation of 10 c.c. of virulent blood; the strength of which should be demonstrated by inoculating an unprotected beast. Should the final inoculation of proved virulent b’ood fail to produce a reaction, and in no way inconvenience the animals so treated, the blood of these animals may be regarded as well adapted for the ])urpose of conferring immunity to others by inoculation. In recommending this process the object is to produce an immunity of hiyh deqrce and lasting influence. The extent to which Inoculation is recommended to re carried out at present. Owing to the quarantine measures adopted Tick Fever is at the present time unknown in this Colony. The opinion that ticks must eventually invade our herds along the coast districts seems to bo fairly unanimous. The ticks might appear suddenly in the near future or may be not for a considerable time. Consequently inoculation of all cattle is not tliought advisable at present, as unnecessary loss may be thereby involved. To at once commence inoculating young cattle (calves and yearliiigs) and thus gradually prepare to minimise the loss entailed by a sudden outbreak of Tick Fever is considered a justifiable precautionary measure, and is therefore strongly recommended. The dry cows should be inoculated when conditions are favourable, and the remainder of the herds when circumstances warrant such procedure. Conditions to be observed with regard to Inoculation. Experience has taught that in order to minimise the loss resulting from inoculation the following conditions must be observed, viz. :— (1.) The cattle must not be travelled long distances either before or after inoculation. (2.) That cattle in moderate condition withstand the effects of inoculation better than those in prime or low condition. (3.) The operation must be conducted with as little noise and bustle as practicable. (4.) The cattle under treatment must be placed in paddocks containing a good supply of grass and water, and there allowed to remain undisturbed. There should be little or no difficulty in conforming with these conditions when inoculation is being carried out on large stations. In treating the small herds of various owners some difficulty may be met with. This, however, may he overcome by having properly salted animals distributed to various centres. The inspector of stock for the district, or a licensed operator, could then deal with the small lots individually or collec- tively ; in the latter case the various owners could conjointly arrange for the accommodation of their cattle at a convenient and suitable place, where the inoculation could be carried out. Faulty Treatment and its Prevention. IMany cases are heard of in Queensland, in which inoculation has not conferred upon the animal so treated the desired protection. Owing to the satisfactory results derived from inoculation, when carried out either experimentally by scientists or on a large scale by reliable persons, one is inclined to the belief that faulty treatment is the cause of failure in many instances. This