DANGEROUS MILK.

Dominion, Volume 2, Issue 455, 13 March 1909, Page 3

DANGEROUS MILK.

EXPERIMENTS ON TUBERCULOSIS.

A SERIOUS REPORT.

Tho enormous danger constantly threatening the inhabitants of New Zealand who cat the* , butter and drink tho milk of the Now Zealand cows, of whom from 10 to 20 per cent, have been estimated to-be tuberculous, receives emphasis from the following interim report of the Royal Commission on Tuberculosis appointed in' Britain in 1901. The commissioners stato:— .

. "Since the date of our second interim report the work of the commission has been mainly directed to determining the special characters of the bacilli which aro the cause of 'tuberculosis in animals other than tho cow, and the relationships of the different types of tho tubercle bacilli which wo havo encountered in man and certain of the lower animals. Tho investisations bearing on these and other matters, referred to in that report as engaging our attention aro not yet compete, and the publication of the results obtained must therefore bo postponed. "In the meantime we.have.thought it advisable to describo the results of a series of experiments which have been carried out by us with a view of obtaining information regarding the excretion or discharge of. tubercle bacilli, in tho milk and faeces of tuberculous catile. ' . . , ' - "In.our sec.ond interim report we .fixpressed tho opinion, as a result of our investigations, that a very considerable amount of disease and loss of life, especially among infants and children;' must be attributed to the cow's milk containing tubercle bacilli. . . Milk. Always Infected, "Tuberculosis involving the udder is comparatively common in cows, and in such cases their milk always contains tubercle bacilli, and is therefore dangerous for human beings consuming it. It was, however, undecided what is .the danger, if any,-attaching to the-milk of tuberculous cows in which the udder presents no. evidence of disease. Wo therefore took the opportunity of making a number of observations, and experiments bearing 011 this point. Tho experiments were made with the milk of cows which had contracted the disease in the natural way. ■ "In natural tuberculosis in the cow, oases' which show such obvious symptoms of the disease as-emaciation and cough should be considered separately from the cases in which there are no such signs, and in which the disease- is to bo recognised during life only by meiius of the injection of tuberculin. ."None of the cows investigated showed any sign of disease of the udder during life, and in all, after slaughtering, the udder was carefully' examined for tuberculous lesions and tubercle bacilli. No tuberculosis was found except ur one case (cow F) in which one quarter of the-udder showed four small nodules. Those cSuld not possibly have been detected diiring life. Healthy Udder No Safeguard. "We found that the milk of the cows obviously suffering' from tuberculosis contained tubercle bacilli whether the milk was obtained in tho ordinary way or was withdrawn from the teat by means of a sterilised catheter. The presence of tubercle bacilli in the milk of cows clinically recognisable as-tuberculous confirms tho ' opinion we expressed in our second interim report that the milk of such cow» fttwt tie considered dangerous for human beings. "The experiments which we havo carried out with regard . .to the jrifectivity . of , tho faeces of tuberculous cows were dictated bv knowledge of the fact .that,,dirt of various kinds from cows and-the cow-shed is almost constantly present in milk as it reaches the consumer. Cows suffering from extensive tuberculosis of the lungs must discharge considerable numbers of bacilli" from the air passages in the\ act .of. coughing, and some of the bacilli thus expelled may find their way into the milk. But our experiments indicate that the excrement of cows obviously suffering from tuberculosis of the lungs or alimentary canal must be regarded as much more dangerous than tho matter discharged from tho mouth or nostrils. Wo have found that even in the case of cows with slight 'tuberculous lesions tubercle bacilli in small numbers are discharged in the faeces, while as regards cows clinically tuberculous our experi. ments show that the faeces contain large numbers of living and virulent tubercle bacilli. , • ' "The presence of tuberculous cows in company with healthy cows in the cow-shed is therefore distinctly dangerous, as some of the tubercle bacilli which escape from their bodies in the excrement are almost certain to find their way into tho milk." Tho report gives full details of the experiments on which the commissioners base the opinions expressed above.