196 



NATURE 



[August 27, 



that when the udder is affected with tuberculosis there are 

 usually numerous bacilli in the milk, which is consequently ex- 

 tremely dangerous. But he also finds that mammary tubercu- 

 losis is not so common as was at one time supposed. At the 

 abattoir of Copenhagen, for example, it has been found that 

 only in i per cent, of tuberculous cattle was there disease of 

 the udder. From twenty-eight tuberculous cows, in which, how- 

 ever, there was no disease of the udder, the milk was injected 

 into forty- eight rabbits, and in only two was there any positive 

 result. He then inoculated forty guinea-pigs with milk from 

 tweniy-one tuberculous cows, in this case with four positive 

 results. Recently he had carried on a new series of ex- 

 periments with the milk from fourteen extremely phthisical cows. 

 In this series the milk was virulent in three cases, so that fiom 

 sixty-three tuberculous cows the milk contained virulent tubercle 

 bacilli in nine cases only. All these cows were affected in a 

 very high degree, and it is probable that in some at any rate the 

 u Ider was affected ; though this could not be demonstrated in 

 the living animal, as it was in three out of the four cases of the 

 second series. Others were affected with miliary tuberculosis in 

 the different organs, a condition which one rarely finds in an 

 animal that is still giving milk, and in one case the supra- 

 mammary lymphatic glands were affected with tuberculosis, 

 although no lesions in the udder itself could be demonstrated. 



In several of the positive cases the number of bacilli in the 

 milk must have been very small, as one only of the two guinea- 

 pigs experimented upon succumbed to the disease, this happen- 

 ing in three instances. 



It should be added that the quantity of milk injected in the 

 later series was larger than in the earlier series. In the two 

 first series i to 3 c.c. was injected, in the third 5 to 10 c.c. He 

 maintained that, although in many cases the milk from phthisical 

 cows is not virulent when the mammary gland is unaffected, it 

 is in a certain proportion of cases, and should always be looked 

 upon with suspicion, and that it is absolutely necessary to take 

 ])rophylactic measures against the use of, such milk, although 

 the danger should no doubt not be exaggerated. 



Meat. — Flesh itself very seldom contams any tubercle. Never- 

 theless it had been proved by a number of experiments that the 

 muscle juice may contain tubercle bacilli, but such cases, accord- 

 ing to the observations of Chauveau, of Arloing, Peuch, Galtier, 

 Nocard, Kastner, and others, are absolutely in a minority. 

 Amongst seventy-three phthisical cows these observers have 

 found only ten in which the muscle juice gave evidence of viru- 

 r nee on injection into rabbits or guinea-pigs, and sometimes 

 the juice inoculated only produced the disease in one of several 

 animals inoculated. 



M. Nocard's experiments in this connection are very interest- 

 ing. He found that when a culture very rich in bacilli was 

 injected into the vein of the ear of a rabbit, the muscle juice of 

 the animal was virulent only when it was killed within five days 

 after the inoculation, from which he argued that the bacilli 

 carried by the vessels to the muscles only preserve their vitality 

 for five days. If to this experimental result be added the ob- 

 servation that tubercle is very seldom developed in the muscles, 

 even during the development of a condition of general tubercu- 

 losis, it must be concluded that muscular tissue is a soil so un- 

 favourable for the growth of tubercle bacilli that they are not 

 able to multiply. The number of bacilli, then, that can be 

 found in the flesh of tuberculous animals is always extremely 

 limited. It is of course true, as M. Arloing has objected to 

 M. Nocard's conclusions, that the circulatory system of a tuber- 

 culous animal can continually receive into it fresh bacilli, and 

 therefore until within only a few minutes before the animal is 

 slaughtered. But, on the other hand, it must not be forgotten 

 that it is only in the case of the development of an acute miliary 

 tuberculosis that one can suppose that the number of bacilli in- 

 troduced into the vessels can be considerable. In ordinary cases 

 in which the tubercular process is developed slowly the bacilli 

 would without doubt escape into the blood in very small quanti- 

 ties, and the number of bacilli that could be found at any given 

 moment in the meat would be very small. Moreover, the experi- 

 ments carried out by Galtier, Gebhardt, and others, render it very 

 probable that the number of bacilli introduced into the alimentary 

 canal, by which infection does not readily occur, plays a not 

 unimportant part in the result obtained. 



Prof. Bang stated that he had recently completed a series of 

 experiments on the virulence of the blood of cows in an advanced 

 stage of tuberculosis. From twenty tuberculous cows he inoculated 

 thirty-eight rabbits and two guinea-pigs with defibrinated blood. 



NO. I I 39, VOL. 44] 



injecting from 10 to 18 c.c. (in four cases only 5 to 9 c.c). In 

 eighteen cases the results were negative, in two positive, and one 

 ol these in which the lesion was small was one of two rabbits in- 

 jected with blood from the same cow. The cow that supplied the 

 blood with which the other positive result was obtained had 

 developed acute miliary tuberculosis after an injection of tuber- 

 culin. Three weeks previously blood from the same cow had given 

 negative results. Even amongst those cases in which the 

 results were negative there were several cases of acute miliary 

 tuberculosis. 



He concluded from the foregoing that the seizure of all tuber- 

 culous animals is too stringent a measure. So long as the 

 tuberculosis is strictly localized, the meat is not a source of 

 danger ; where the malady is generalized, the consumption of the 

 meat may be dangerous, although it is not always so. The 

 eating of uncooked n)eat should be discouraged, but the best 

 means of avoiding danger to the health of man is to take all 

 possible measures for preventing the propagation of tuberculosis 

 amongst our domestic animals. 



Prof. Arloing, of Lyons, contended that the question of trans- 

 missibility of tuberculosis from animals to man was one of very 

 great importance, but he admitted that the diagnose precoce was 

 very difficult. The danger to children of drinking milk from 

 tuberculous cows was great, and he thought could scarcely be 

 exaggerated. Moreover, he held very strongly that, except 

 under certain special circumstances, the total condemnation of 

 tuberculous meat was necessary, and on grounds of public health 

 he dissented entirely from Dr. Bang's position. 

 , The flesh of all tuberculous animals should be suspected as 

 dangerous to health, the more so as meat was very often in- 

 sufficiently cooked, the bacilli present under these conditions 

 remaining pathogenic. From statistics he had gathered, he fell 

 no doubt on this subject, and although it might be possible, by 

 first carefully cooking under public supervision, to allow the 

 flesh from animals in which the tuberculosis was localized to 

 be sold, he still maintained his position that total confiscation of 

 tuberculous meat was the safest method to be adopted. It was 

 necessary, however, that in the first in--tance we should have a 

 system of strict inspection, not only in our large towns, but also 

 in all the smaller centres of population. 



A paper was then given by Prof. M'Fadyean (Edinburgh) 

 and Dr. Woodhead (London), on the transmission of tuberculosis 

 from animals to man, by means of flesh and milk derived from 

 tuberculous animals. They maintained that the evidence as to the 

 transmission through the flesh or milk of tuberculous animals was 

 very conflicting, apparently in great part because the methods 

 used were different, and the conditions were not uniform. They 

 had attempted to follow the line of infection of tuberculosis in a 

 number of children, and had found that in 127 cases analyzed 

 tubercle of the intestine was present in 43 ; 24 of these cases 

 occurring between one and five and a half years ; tubercle of the 

 mesenteric glands was found in loo cases, or in nearly 79 per 

 cent, of the whole ; here, again, 62 of these occurring between 

 one and five and a half years ; and of 14 cases in which the 

 mesenteric glands were primarily affected — i.e. no trace of 

 tubercle could be found in any other part of the body — 9 were 

 referred to the same period. It was noticeable that of these 100 

 cases only 20 were diagnosed during life as suffering from abdo- 

 minal tubercle. From all that could be learned from these cases 

 (and reference could be made to a large number of other sets of 

 statistics practically proving the same point), it was evident that 

 intestinal and mesenteric tubercle are most frequently met with 

 in children during the period after they are weaned, at which 

 time cow's milk has been substituted for mother's milk. The 

 p jint of entrance appeared in these cases to be by the intestine. 

 They had come to the conclusion that in some cases at least the 

 tubercle bacilli had passed from the intestine into the mesenteric 

 glands without leaving any trace of lesion to indicate their point 

 of entrance. There could now be no doubt that tubercle bacilli 

 were sometimes present in the milk from tuberculous cattle, 

 especially where the udder was affected, and they had been able 

 to obtain such bacilli embedded in the epithelium of the milk 

 ducts, or lying free in the ducts after the death of the animal. 

 They concluded that wherever the presence of a tuberculous 

 condition of the udder could be demonstrated clinically it would 

 be little less thart criminal to give the milk to delicate children, 

 or even to children suffering from any catarrhal derangement of 

 the intestine, a condition that is specially frequent amongst the 



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