CATTLE DISEASES

Wanganui Chronicle, Volume 76, Issue 105, 6 May 1933, Page 20 (Supplement)

CATTLE DISEASES

FREEDOM FROM TUBERCULAR INFECTION INTERESTING POINTS IN ELIMINATION Probably in no other area in Great Britain has the elimination of tuberculosis from the dairy stock received so much attention as in the Ayrshire district. I have recently been able to examine their methods of eradication and to take stock of the situation arising from tne large number of free herds in the district, writes a special representative of the Farmer and Stockbreeder.

The south-west of Scotland can be regarded more or less as a self-con-tained unit. Few cattle are brought into the area, and this contributes to the success of the anti-tuberculosis movement.

The suitability of any particular farm for carrying a stock of tuberculin-tested cattle largely depends on its boundaries. An interesting example is the farm of Mr. Quentin Dunlop, at Greenan, near Ayr. Roughly triangular, it is bounded on one side by the sea, on the second by a main road, leaving only one leigth in contact with a neighbour. This is double fenced, with a margin of seven or eight feet to prevent possible contact between the tested cows and animals on the other farm. Out-of-doors Young Stock. After reactors were discarded some seven years ago, there have been no further cases. The young stock from reacting cows had all been brought into the herd and continued free. They are raised entirely out of doors, not being housed until they come into the dairy herd. At the start it was. of course, neeecssary to disinfect and modernise the building formerly occupied by reacting cows. All unnecessary wood-work was cleared out, a concrete wall now separating two lines of cows facing inward. Some 48 cows are kept here and about 30 elsewhere, all tested. No cattle are brought in from outside, and pigs and poultry are debarred access to the cattle pastures. Buying in no alien cattle except an occasional bull from tested stock enables many herds to be kept free from tuberculosis even without regular testing. Other breeders, however, point out that such freedom from contact with “imported” cattle cannot always be guaranteed. One of these, for example, while all in favour of keeping tys pedigree herd free, finds it necessary to buy in store cattle for feeding to produce sufficient dung for his early potato crops. * The risk of importing tuberculosis is such that is it impos* sible to maintain a fully tested herd.

To establish a free herd from existing stock it is a great advantage to have an off-lying farm to which reactors can be removed. This was the system adopted by Colonel Houldsworth at Threave, near Crosshill, some eight years ago. The homo buildings were thoroughly disinfected, all parts liablo to harbour germs being carefully scorched with a blow lamp.

Calves from reactors were immediately removed and reared in the clean buildings on milk from tested cows. Here, as elsewhere, it was demonstrated clearly that the disease is not inherited and that there need bo no sacrifice of good breeding stock. • The herd was entirely free after the second year. Up-to-date Practice. In the case of Mr. W. Thompson, whose farm at Brae of Auchendrano is a wellknown example of up-to-date practice, the herd was first cleared of tuberculosis some years ago. Here, too, an offlying farm was employed to carry the reactors until they were dispersed. Thus the course of pedigree breeding was not seriously upset. In the existing herd there have been no reactors for about eight years. Buying no strange stock and keeping the pastures free from contamination by pigs or poultry are measures taken here for keeping the cowr free.

On these farms tested herds have been lyiilt up by eliminating reactors from an existing herd. But at Woodland Dairy, near Girvan, a free herd was established by Messrs. J. and W. Forbes, about seven years ago by the purchase of heifers from free herds. Before the new stock was brought in the buildings were completely disinfected by the blow lamp method and with the exencise of proper precautions, there have not been any reactors since. The farm does not join any other directly. and rabbits, which are held in very bad repute, are carefully controlled. Poultry are not allowed on the grass, nor are any but tested cattle purchased. On this, as on most of these farms, supplementary grazing is by sheep.