TUBERCULOSIS.

Wairarapa Age, Volume XXXI, Issue 3006, 1 October 1908, Page 3

TUBERCULOSIS.

HOW DISEASE IS SPREAD.

:■ ■ Tbe annual report of Mr J. A. | •Gilruth, Chief Veterinarian, has \ ' '"* jjust been presented to Parliament. lAstead of the ravages of tuberculosis I domestic stock being lessened I they are, Mr Gilruth shows, being extended, and this by means of a pre-; ventib'% cause—the skim-milk and whey tanks of dairy factories. The natural remedy is pasteurisation of thes9 residual products. The percentage of pigs found to be | tubercular by the officers of the vet- , erinary division in their inspection of stock at abattoirs and meat-freezing works last year exceeded ( that of all the cattle. Considering, says Mr Gilruth, that ths vast majority of pigs Examined are killsd for bacon-curing purposes, which means at least that they are not full-grown but are genarWally about a year old, the position is , \Mjthe nnre remarkable. To what, then, the prevalence of tuberculosis in the pigs of the Dominion be attributed? It is proved by the returns that certain districts are more badly iiife.:ted with porcine tuberculosis fc viaa i others. These districts are found ""tfjbvthosealso badly affected with ' bavine tuberculosis. Yet this does not explain the prevalence of the for•msr, fir the two animals are rarely horded together. The connection is, .however, apparent when we remember that the young pigs, particularly ■those being fattened for bacon, are flar/ely fed upon skim-milk. This iskim-milk is returned from the factory, and it is seldom that the supplier received the skim-milk from his own whole-milk alone. One or two badly tubercular cows may contaminate the whole milk-supply of a herd, an 1 the skim-milk of this may in rturn contaminate the whole or a percentage of the young pigs of the /owner or of another supplier to the ' same factory. At one time it was held that the milk of a tubercular cow was only whsn the udder was itself Hfdiseased. This, however, declares Ttha Chief Veterinarian, has been complately disproved. Recently ithas been shown by Calmette, Guerin, ;and others that one of the most fertile sources of contamination is the faeces of cows, this being tha vehicle by which the bacillus is tprobably most frequently dispersed. •Ouatamination of the milk-supply is thus readily understood. Calves are without doubt also frequently infected by means of milk, . skimmed and whole. That they are ■''■'" ■; but infrequently found affected does , not disprove this, for it has been shown that in thsm the bacillus may Jie dormant, so to speak, within a lymphatic gland for months, and yet possess all its vitality, only waiting for some constitutional derangement, in all probability, to set up the characteristic pathological disturbance. The remedy for all this is obvious, is one which Mr Gilruth says he has lb- urged repeatedly for years, and is T one that can only be applied by legal the compulsoi-y sterilisation of all skim-milk-at the factory before it is returned to the supplier. Were this inaistad upon, both the farmer and •-th3 general taxpayer would early feel j the benefit. I Butter,is, fortunately, not so liable to be a frequent vehicle of contagion, because the sepai'ator retains the bacilli ip the skim-milk and the sediment to a great extent, although it. , that the fat globules thrown out in the form of cream , ' must carry a certain number of bacilli when the milk is badly -affected, for it is on record that butter made from infected milk has been proved to be infectious for jguinea pigs, and bacilli .may remain alive arid virulent for forty nine days in salted v butter. I Ths foregoing remarks, concludes the Chief Veterinarian, have been introduced Bolely in the endeavour to ♦-explain the prevalence of tuberculoid -sis amongst our pigs, and the appar- -< ent absence of any decrease in the -disease:amongst our herds generally, .jjdgina; by the post-mortem examin'ations at meat-works and abattoirs. "~~* As the question of eradication does not in, any degree come within the jurisdiction of the Veterinary Division, I have now no suggestions to make, but may bo permitted to draw .attention to recommendations which I ' have made in former annual reports.