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An experimental milk-supply
12
A n Experimental Milk.Supply
AN EXPERIMENTAL
Ev~bn¢~at~
MILK-SUPPLY. ~
BY W. ROBERTSON, M.D., D.P.I-I., h'iedical Officerof Health of l~aisley. M~:ett has been said and written upon the vexed question of the milk traffic. Suggestions have been offered times without number as to the methods for the better housing of cows, the due care of the animals, and the careful treatment of the product. Much has been done to improve our byres and cowsheds, but little impression has yet been made upon the mind of the cow-feeder. All of us know what his confirmed ideas are as regards light, ventilation, and air-space. Just as an interested individual opposes us in committee when we advocate some structural alterations, so does the dairy-farmer or cow-feeder turn a deaf ear when we attempt to prove to him how much better his stock would be were the animals housed under improved conditions. In either ease the pocket is to be touched, and the purse-strings are tightened at the first alarm of interference. It is a natural opposition, but' not always the best by any means.
This subject is one that ought to demand a greater interest from the medical officer of health--I mean active interest. Were he to poke his nose more frequently into byres, he would be startled from his lethargy. We are advancing all along the line, but in the direction of byres and byte construction we seem to have come to a standstill. The error, if I dare say so, seems to be due to the want of a close study of the subject. Regulations, it is true, are in existence, but where would we be if we had no police to enforce punishment and maintain law and order ? A chief constable does not content himself by hanging up a notice warning people against doing this, that, or the other thing ; neither should we rest content with the mere regulations. Were the milk traffic a pure one in more senses than one, prosecutions would be uncalled for; but prosecution should empower us to push our attacks further. Filtering of milk should be made compulsory, so should the cleansing of ~he teats and the washing of the milker's hands. Strict rules ought to be laid down as to the distribution of milk from house to house; and if message boys and girls are to be allowed, a register of these should be kept by the medical officer of health. Again and again one sees these urchins placing their lips * Baper read at mee~ing of Scottish Branch of the Incorporated Societyof Medical Officersof Health at Glasgow, November, 1900.
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to cans that are to be taken to a private customer ; or some halfdozen cans may be deposited in the passage of a tenement or at the gateway of a Villa, while a passing dog elevates a leg to douche the lids with urine. That is no fanciful picture. You have witnessed it, but nothing is done to check the evil. That is why, I say, we have much to do to elevate our milk traffic to a level approaching perfection, ll{essage-boys should be abolished, and in their places men sent round with hand-barrows arranged in such a way that the cans will be suspended from hooks. Soiling of cans will thus be avoided, and the other objections that I have mentioned will be met. Some may smile inwardly at my " mare's nest." Quite so, but what are we d9ing to make matters better ? We cannot, like Cronje, sit still, and expect the cow-feeder to surrender until he is compelled to fall into line with common-sense. Those of us who are medical officers of large towns feel this matter keenly. We dilate upon " s u m m e r diarrhsea" at great length, and bemoan the heavy mortality; we blaspheme cocci and every organism t h a t lives and has its being; but we forget about the dirty byres, the sediment of filth in the milk, and leave the sanitary inspector to ~ake sampl6s under the'Food and Drugs Acts. Some of you, most of you, perhaps, do not view Municipalization in a very favourable light. I do not want to digress, but I ask you to give a serious thought to this subject; and I am bound to say you will be partially converted, at least, to the doctrine of Municipal Milk Control. I simply outline the pen-picture before you of an everyday byre controlled by a man who treats his cows as milking machines, as opposed to a model byre constructed under hygienic principles controlled by those who can make the mos~ stringent rules and select their workers, the milk dis~ribuWd in locked cans, and no temptation offered to add two par~s of skimmed milk to one of sweet, and many other nefarious little tricks. So, it was with the principle of a municipal byte in my mind that I approached my local authority. It was a new subject, and I raised the question wi~h some trepidation. My proposal was as follows : We have an Infectious Diseases Hospital under our control. Let us, therefore, contract with someone to provide us with milk; but the milk we demand must be taken from cows that have not responded to t h e tuberculin test. And if any cow-feeder agrees to come to our aid, we shall give him an extra price for his milk. I was gratified beyond measure when the proposal was heartily supported, and I was told to proceed. The better price of the milk tempted several, but when the conditions for the housing of the cows were laid down all ran away save one. With him I was able
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to come to terms. In brief, the following were the demands made : The cows must be selected, tested, and housed in a byre constructed upon modern principles. There was to be free ventilation, a good amount of window and roof light, with feeding-passage at the head for only one row of cows. I may say our maximum requirement was milk from 14 sows. The contract was for three years, and I had the consent of my local authority to slaughter and pay for any animals that reacted to the tuberculin test. Other requirements that I made were that the milk was to be carefully filtered, and conveyed to the hospital in locked cans. The sans could only be unlocked at the hospital. They were specially constructed upon the principle of having no inside corners or crevices. The milk was filtered through a fine mesh of wire, then through a layer of st'erilized cotton wool. The filter was also an adaptation of my own. Fortunately, the sow-feeder possessed a large steam boiler. From this a pipe was led to a galvanized iron tub, in which all our cans were to be. washed; and next to it was erected a rough sterilizer, in which cans were subjected to the influence of steam from another pipe. When the building was complete, we had a byre under our immediate control, and infinitely superior to any other in the municipality. I had every confidence that it would supply an excellent object-lesson to the conservative-minded cowfeeders. So pleased is our contractor with the result of our joint effort, that he intends ere the summer comes on to convert his other and ancient-looking byre into one like that about to be described. He also is going to keep no other than tested cows. First~ then, a few words as to the byre. Its dimensions are as follows: 53 feet long, 17 feet broad, and 13 feet 6 inches high. The inside walls are coated over with concrete cement pIastered upon the stone wall. The floor, division blocks, and trevass are all built of the same material. There are neither rafters nor crossbeams in the byre. The ceiling is dome-shaped and lined with wood, painted over with a cream- eoloured paint. This aids in the lighting up of the byre. In the roof at stated intervals are two ventilating-shafts surmounted by 1S-inch Howard revolving ventilators. Flap shutters can close these outlets at will. At the end of the byte furthest from the entrance-door there is a g-foot Blaskman fan, which at intervals during the winter will extract. foul air from the byte. The cows are allowed, roughly, 800 cubic feet of air-space each. When not in action the outlet of the fan acts as upcast shaft. Three windows on the south wall of the byre open inwards on a bottom hinge, and permit a current of air to circulate about the heads of the cows. The cows face these
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windows, which shed a good light into the byre. Another large window is at the gable end of the byre--that is, opposite the Blackman fan. This opens on a side hinge :throughout its whole length. There are, in addition, three roof lights. The division blocks have rounded corners, and the fireclay feeding-troughs have been so built that no crevices exist. The feeding-passage at the head of the cows is 3 feet wide. The channel behind the cows is 18 inches wide and 6 inches deep. The rear passage, again, is 5 feet wide. The cows are stalled in pairs, and have an abundance of space in which they may move or lie down. The drainage is perfect, and the dung-hea p is fully 50 yards away. A water-pipe with a thin hose attached to it has also been introduced into the byre. There is no attempt at artificial heating, nor wilt any be made. My difficulty is to keep the byre at 59° F. Improvements that could be suggested are windows on the north wall, but the presence of an engine-house precluded any windows on that side. Inlets of fresh air nearer the noses of the cows might have been inserted; but when I inform you that most of the improvements were carried out with a good-natured scepticism on the part of the cow-feederl and all expenses came out of his pocket, you can understand I dared not demand too much. For ~he same reason I could not ask for a lining of glazed bricks on the inside walls. In process of time I hope to see the walls painted, to a certain height at least, with white eolour. Lime-wash would be spoiled by the hose-pipe. There still remains one very important matter in byre construction seldom touched upon. I refer to the floor on which the animals lie. The hard floor is an objection, and tries the knees of Che animals. Tar macadam appeals to one as a likely substitute, but the heat of the animals' bodies would soften this, with disastrous results t6 the cow's hide, udder, and teats. An objection to this form of byre is that cows may push their heads over the trevass and soil their beds with droppings. The cow-feeder has, by an ingenious arrangement, fixed an iron rod from the one end division block to the other. This rod keeps the cows in their places, as they cannot push further forward than the rod. It is a simple but clever idea. No originality is claimed for the style of the byre, but we can say, in Paisley at least, that we have held other antiquated byres up for a ridiculous comparison. I refer to byres where the cow is fixed with her nose at the wall. A wider passage at the head would be urged by some, but even the wider passage would not obviate the evil that threatens the cows. I mean a constant indoor life can never approach the benefit that
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An Experimental Milk.Supply
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must follow an outdoor life--a life, let me say, that is peculiar to animals; a life that has been gifted to them by God, but which has been robbed from them by man in his desire to make money. I hope the time is not far distant when by some means or another dairy cows especially will be compulsorily tethered in open courts, as against hermetically closed byres. The ingenuity of man is not beyond erecting buildings ~hat will provide cows with a maximum of fresh air and light, and the needed shelter against inclement weather. Cows need no more. Some far-seeing and intelligent individuals have adopted such a system, and the day must come when such a principle will be universal. Just as we expect to curtail tubercular diseases by improved dwellings and open air-spaces, so must we eradicate tuberculosis in cattle by altering their modes of living. Tuberculin tells us that tubercular mischief is present, but there it stops, for we cannot, as matters stand, hope to advance much further. Compensation would be the sinking of thousands and thousands of pounds, for no sooner would the diseased animals be cleared out than another set would begin to pine in the dark, stuffy, and insanitary bytes that abound in the British Isles. If we were to construct a byre that would practically obviate the chance of tuberculosis, we should have the cows stalled as I have indicated--that is, in one row, and a feeding-passage at the head; a continuous series of windows from one end of the byre to the other behind the cows. Provision could be made for these windows to open to their full extent when the superintendent elected by choice or advice to do so. There would be no wall at the opposite side of the byre, that is, in front of the cows. Iron pillars at intervals would support the roof. In inclement weather, when the wind was sweeping into the byre through the pillars, straw matting could be suspended at intervals from pillar to pillar or throughout the entire length of the byre, to protect the animals. If Government would advance money to permit the universal construction of such by~?es, it would serve the end in view better by far than compensation. In support of such construction of bytes I have only to refer to the experiment made by Professor Axe, and gladly quoted i n this paper, and I humbly subscribe to Professor Axe's doctrine that fresh air, not cubic space in a closed-in byre, will obviate tubercular diseases in cattle. In that connection I might parenthetically remark that a cow-feeder will tell us that high-class cows will not do well in open byres. "Weeds" and other ills must follow in the wake of a cold byre. :But here again
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we must meet that argument by affirming that the life led by these cows has accustomed them to heat. Submit them to the opposite condition, and they will thrive better and last longer. It is all a question of custom. Less than ten years ago people supposed a case of pulmonary consumption should on no account be permitted out of doors on a cold day. The simile applies to the cow. Milk and money, however, are at the foundation of the housing of the cow question. Again, there are the North of Ireland cows. These do well and milk well, though grazed on the hillsides. Let us bring them into a byre, and they perform ~heir functions feebly. A knowledge of these minutia will convert one into thinkhlg that a trial of a different type of byte will find the cows, well-bred or crossbred, accustoming themselves in time to their cnew modes of living. Without going further into detail,let me quote to you one or two most convincing extracts from an exhaustively detailed report made by Professor Wortley Axe last year. Under the auspices of the :British Dairy Farmers' Association he was asked to carry out extensive experiments with tuberculin. Nine different herds were selected, containing 461 cows and 19 bulls. There were among these 335 shorthorns, 67 cross breeds, 47 Ayrshires, 3 Dutch, and 1 :Brittany. Now, for sake Of comparison, let me take four herds mentioned in the report. One herd is bad, the second good, and the third excellent ; the fourth is the type we see every day. Herd No. 1 eont~ained 86 cows, housed in a double shed. Each animal was allowed 500 cubic feet of air-space. Fresh cows were brought in from time to time and kept forward in flesh, and at the expiration of their milking periods sold fat to the butcher. Once in the shed, they were kept there until they ceased to give milk : 90 per cent. reacted to the tuberculin test. The cows looked so plump and well that several had ?so be slaughtered to convince the owner of the existence of tubercular disease. Herd No. 9~contained 76 Cows and 7 bulls. The animals led an outdoor life from May till November, and were allowed out during the winter for a short time each day. The sheds were low and primitive in character; they were open to the yard on One side. In winter the opening was partially closed by means of hurdles loosely drawn with straw. Only 8"6 per cent. reacted. I have italicized the word "primitive," as it has a most important bearing upon the point I want to bring out. The stock was not of the finest pedigree, but was useful for feeding and milking. On ~ha~ point the Royal Commission in 1898 made an important remark when i t said: "One serious
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feature in the distribution of this disease is its prevalence among high-class pedigree stock." In the words of Professor Axe, " T h i s is not due to a predisposition so much as the retention of valuable strains for long periods and for breeding purposes. Also the offspring of these valuable animals are subjected to more artificial treatment than ordinary animals." Herd No. 3 contained 41 cows. The animals were bred on the farm, and led an outdoor life night and day, summer and winter. The animals knew the byres at milking times, and only in very severe weather were driven in for shelter. Not one cow reacted to the test. Herd No. 4 comprised 59 cows and 1 bull. The cubic air-space was 596 feet per animal. In winter they were confined to the byre night and day ; in summer out at pasture. 76"9 per cent. reacted. These facts are worth volumes o~ dissertations upon tubercle bacilli; they must prevail some day. It rests with us to~ make them prevail. Those who adopt the open-air treatment of their cows declare--and I quote their own words from the report given at the t i m e - - " The shortage of milk is eeonpensated by the greater cleanliness qf the milk, the healthiness of the cows, and the less expense and trouble in looking after thenT." I sincerely wish cow-feeders would see the obvious reason in this. Now a point with reference to the udder. Of the 461 cows tested, 51, or 11 per cent., were found to have disease of the milkgland in one form or another: 55 per cent. of these glands were from animals that reacted to the test ; the other 45 per cent. were in the non-reacting animals. But the chief point worthy of remark is that tubercular affection of the udder was discovered to be very rare even in the reacting animals. It shows us how the appointment of a veterinary examining officer may, after all, be of little assistance. To prove his case he witl require to produce bacteriological and microscopical proof of the existence of bacilli from every udder he condemns. Even the response to the tuberculin test will not help him, for the tubercular mischief may be elsewhere than in the udder. Now, let me say a word about tuberculin, an agent~ that h a s been awarded as much praise as it has received abuse. The abuse has come from those who have been affected by the test; the prMse has come, and continues to come, from our leading veterinarians at home and abroad. The man with a filthy house is loudest in his condemnation of the dwelling next door, but when the first man's house is condemned he begins to miscall everyone. Many cow-feeders stand in an analogous position when we make tuber. culin the detective. In our experiment 17 cows were tested, and
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3 reacted. They were mostly cross-bred cows, which are less frequently tubercular than the better milking and higher-classed Ayrshire cow. The test was carefully carried out by the bm'gh veterinary inspector, and every detail as regards preliminary rest and taking of temperatures had attention. The charts indicate a rise in the reacting animals to 106° F. The tuberculin was procured from the Royal Veterinary College, and strict antiseptic precautions were used. In each of the reacting animals the temperature began to rise at the ninth hour, and continued till the fifteenth hour. The three reacting animals were slaughtered, and in every one was the tuberculin tesfi confirmed. In no instance could one say the disease was widespread. Subsequent to the testing I was informed that one cow had been tested three months before, and had reacted. She had failed to give a response to the detailed test, already referred to. The cow-feeder was willing to stake money on the fact that though she had shown a reaction three months ago, there would be no " ~ubers" found in her. I accepted his challenge, and the cow WaS led to the slaughter. I have reckoned her in m y original statement as one of the three. As I have already said, th~ cow showed tubercle, and proved tuberculin to be reliable; bug the very important fact was brought out that, contrary to what we, read, the tuberculin had provoked a long immunity. We are led to believe that a c o w may, wi¢h certain result, be retested in six weeks. This is a c a v e and a danger Signal. It means Chat the unscrupulous dealer:--and dealers of that type do exist--may sal~ animals that will defy any t~st save that of the microscope when the udder is affected: Moat of you were aware of the "salting," no doubt, but I dare say it is new to hear that the immunizingeffect can remain so long. Before proceeding further I might add that in six months agai~ we intend to have the cows retested. Lastly, let me attempt to summarize and answer the objections raised against tuberculin. One reason given to prove the fallibility of the test is that cows have reacted and yet have lived so well and so long that there could not have been tubercle present. People, w h o believe an argument such as that cannot be controverted. We have hundreds of instances of men and women who have beer~ told that they had nofii:~long to live because they were smitten with tubercular disease, yet they are alive and prospering. It would be, a pretty argument to conclude from that that there was never any tubercle present. Only the slaughter-house can settle that argument when applied to cows. Secondly, animals react, and a~ t h e slaughter-house give a negative result. This seems startling or~
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the face of it, but let us ask some questions. Who performed the test ? Was it a qualified person ? What was the temperature for two days prior to the application of the test ? What was the condition of the animal? What about parturition? Was it recent? Who performed the post-mortem ? Was every gland examined ? I leave these questions to be answered. It is strange that those of us who favour the test are willing to bring evidence of every kind to bear upon our research, but those who speak against tuberculin are content to make sweeping assertions, devoid of conclusive proof. When we know that a few isolated millet-seed deposits can yield a reaction, we can understand how an untutored eye, willing, perhaps, to be timorously blind, can overlook these tiny specks. An off-hand opinion of that kind is quite valueless. Let us take one sentence from Nocard's little book. From him we hear a different story. "Experiments made by thousands in all countries have shown that the ' lymph' of Koch, injected in small doses under the skin of cattle suspected of tuberculosis, sets up in tuberculous animals alone an intense febrile reaction, permitting one to assert the existence of lesions so minute that other methods of diagnosis (clinical or bacteriological examinations and inoculations) would be powerless to reveal their presence or even to make one suspect their existence." Nervous animals may be irritated or upset by the injection of tuberculin or the frequent insertions of the thermometer into the rectum, but a wise and careful veterinary surgeon will not jump to a hasty conclusion about such an animal should she show a rise in temperature. But instances such as that are quoted against tuberculin. The opponent of tuberculin views it as a wicked invention of a hysterical band of scientific men. There is the familiar argument that a cow may not react and yet will show diffused tuberculosis. The widespread existence of the disease is ?she reason for the imperfect reaction. The thermometer and general appearance of the animal will, however, guide a skilled veterinarian. It is given as an argument against tuberculin that it causes abortion, perhaps diarrhcea, and produces constitutional symptoms too n~merous to mention. Our leading authorities do quote~eases where tuberculin has produced these disorders, but they are frank when they make their admission. We know that diphtheria antitoxin can and does work wonders when given in big doses and early, but because it now and again is followed by urticaria, nervous symptoms, or rheumatic pains, it does not surely follow that antitoxin is a silly drug in the market. Just as antitoxin can be said to be a substance free from danger to the individual acted
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upon, so we can say tuberculin--and I make it emphatic, pure tuberculin--well and carefully injected, is a harmless agent. The most dangerous objection yet launched at tuberculin has been the latest. It is to the effect that the injection of this material produces tubercular disease--in other words, tuberculin is an infecting agent. This, to the layman, must be like a sparkling ray of golden hope. If any tuberculin does produce infection, then it ought to produce a lesion at the seat of puncture ; and if it can be proved that tuberculin has done so, then the only answer must be that there was something radically wrong in the manufacture of the tuberculin. Tuberculin is prepared in this way (Nocard) : " A culture on glycerine bouillon is incubated for six weeks at a temperature of 37 ° C. This is next sterilized in an autoclave at 110° C. ~ext it is concentrated in vacuo in the presence of sulphuric acid or in a water-bath until the culture is reduced in bulk to one-tenth of its original size. It is then filtered through germproof filters, and stored away from heat and light in hermetically closed vessels." If bacilli can come safely through so many ordeals, then our whole knowledge of the vitality of the Koch bacillus is utterly at fault. On the other hand, if no local lesion is found, and tuberculosis develops in a cow that did not react at the first test, the argument all inclines to show that the animal developed the diseasg in some other way. Bacillus-free tuberculin cannot, as far as bacteriology teaches, produce tuberculosis. Of course, if anyone wants to condemn tuberculin, it is easy to say tuberculin was the culprit that caused the diseased condition. The fourteen cows at present stalled in our byre will in course of time be sold. The cow-feeder expects them to go to the slaughterhouse; there I shall have a further opportunity to follow up the tuberculin investigations. I have communicated with :Professor MeFadyean of London and Professor Muir, Professor of Pathology, Glasgow University, with reference to this question of the infection by tuberculin. I have answers from both, with full authority to state that in their opinion infection is quite impossible if tbe tuberculin has been carefully prepared. They cannot speak for the tuberculin that is not got from standard makers. Some time ago Professor Delgpine~.:i~f Manchester made this point very clear.
A n Experimental Milk.Supply
AN EXPERIMENTAL
Ev~bn¢~at~
MILK-SUPPLY. ~
BY W. ROBERTSON, M.D., D.P.I-I., h'iedical Officerof Health of l~aisley. M~:ett has been said and written upon the vexed question of the milk traffic. Suggestions have been offered times without number as to the methods for the better housing of cows, the due care of the animals, and the careful treatment of the product. Much has been done to improve our byres and cowsheds, but little impression has yet been made upon the mind of the cow-feeder. All of us know what his confirmed ideas are as regards light, ventilation, and air-space. Just as an interested individual opposes us in committee when we advocate some structural alterations, so does the dairy-farmer or cow-feeder turn a deaf ear when we attempt to prove to him how much better his stock would be were the animals housed under improved conditions. In either ease the pocket is to be touched, and the purse-strings are tightened at the first alarm of interference. It is a natural opposition, but' not always the best by any means.
This subject is one that ought to demand a greater interest from the medical officer of health--I mean active interest. Were he to poke his nose more frequently into byres, he would be startled from his lethargy. We are advancing all along the line, but in the direction of byres and byte construction we seem to have come to a standstill. The error, if I dare say so, seems to be due to the want of a close study of the subject. Regulations, it is true, are in existence, but where would we be if we had no police to enforce punishment and maintain law and order ? A chief constable does not content himself by hanging up a notice warning people against doing this, that, or the other thing ; neither should we rest content with the mere regulations. Were the milk traffic a pure one in more senses than one, prosecutions would be uncalled for; but prosecution should empower us to push our attacks further. Filtering of milk should be made compulsory, so should the cleansing of ~he teats and the washing of the milker's hands. Strict rules ought to be laid down as to the distribution of milk from house to house; and if message boys and girls are to be allowed, a register of these should be kept by the medical officer of health. Again and again one sees these urchins placing their lips * Baper read at mee~ing of Scottish Branch of the Incorporated Societyof Medical Officersof Health at Glasgow, November, 1900.
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to cans that are to be taken to a private customer ; or some halfdozen cans may be deposited in the passage of a tenement or at the gateway of a Villa, while a passing dog elevates a leg to douche the lids with urine. That is no fanciful picture. You have witnessed it, but nothing is done to check the evil. That is why, I say, we have much to do to elevate our milk traffic to a level approaching perfection, ll{essage-boys should be abolished, and in their places men sent round with hand-barrows arranged in such a way that the cans will be suspended from hooks. Soiling of cans will thus be avoided, and the other objections that I have mentioned will be met. Some may smile inwardly at my " mare's nest." Quite so, but what are we d9ing to make matters better ? We cannot, like Cronje, sit still, and expect the cow-feeder to surrender until he is compelled to fall into line with common-sense. Those of us who are medical officers of large towns feel this matter keenly. We dilate upon " s u m m e r diarrhsea" at great length, and bemoan the heavy mortality; we blaspheme cocci and every organism t h a t lives and has its being; but we forget about the dirty byres, the sediment of filth in the milk, and leave the sanitary inspector to ~ake sampl6s under the'Food and Drugs Acts. Some of you, most of you, perhaps, do not view Municipalization in a very favourable light. I do not want to digress, but I ask you to give a serious thought to this subject; and I am bound to say you will be partially converted, at least, to the doctrine of Municipal Milk Control. I simply outline the pen-picture before you of an everyday byre controlled by a man who treats his cows as milking machines, as opposed to a model byre constructed under hygienic principles controlled by those who can make the mos~ stringent rules and select their workers, the milk dis~ribuWd in locked cans, and no temptation offered to add two par~s of skimmed milk to one of sweet, and many other nefarious little tricks. So, it was with the principle of a municipal byte in my mind that I approached my local authority. It was a new subject, and I raised the question wi~h some trepidation. My proposal was as follows : We have an Infectious Diseases Hospital under our control. Let us, therefore, contract with someone to provide us with milk; but the milk we demand must be taken from cows that have not responded to t h e tuberculin test. And if any cow-feeder agrees to come to our aid, we shall give him an extra price for his milk. I was gratified beyond measure when the proposal was heartily supported, and I was told to proceed. The better price of the milk tempted several, but when the conditions for the housing of the cows were laid down all ran away save one. With him I was able
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to come to terms. In brief, the following were the demands made : The cows must be selected, tested, and housed in a byre constructed upon modern principles. There was to be free ventilation, a good amount of window and roof light, with feeding-passage at the head for only one row of cows. I may say our maximum requirement was milk from 14 sows. The contract was for three years, and I had the consent of my local authority to slaughter and pay for any animals that reacted to the tuberculin test. Other requirements that I made were that the milk was to be carefully filtered, and conveyed to the hospital in locked cans. The sans could only be unlocked at the hospital. They were specially constructed upon the principle of having no inside corners or crevices. The milk was filtered through a fine mesh of wire, then through a layer of st'erilized cotton wool. The filter was also an adaptation of my own. Fortunately, the sow-feeder possessed a large steam boiler. From this a pipe was led to a galvanized iron tub, in which all our cans were to be. washed; and next to it was erected a rough sterilizer, in which cans were subjected to the influence of steam from another pipe. When the building was complete, we had a byre under our immediate control, and infinitely superior to any other in the municipality. I had every confidence that it would supply an excellent object-lesson to the conservative-minded cowfeeders. So pleased is our contractor with the result of our joint effort, that he intends ere the summer comes on to convert his other and ancient-looking byre into one like that about to be described. He also is going to keep no other than tested cows. First~ then, a few words as to the byre. Its dimensions are as follows: 53 feet long, 17 feet broad, and 13 feet 6 inches high. The inside walls are coated over with concrete cement pIastered upon the stone wall. The floor, division blocks, and trevass are all built of the same material. There are neither rafters nor crossbeams in the byre. The ceiling is dome-shaped and lined with wood, painted over with a cream- eoloured paint. This aids in the lighting up of the byre. In the roof at stated intervals are two ventilating-shafts surmounted by 1S-inch Howard revolving ventilators. Flap shutters can close these outlets at will. At the end of the byte furthest from the entrance-door there is a g-foot Blaskman fan, which at intervals during the winter will extract. foul air from the byte. The cows are allowed, roughly, 800 cubic feet of air-space each. When not in action the outlet of the fan acts as upcast shaft. Three windows on the south wall of the byre open inwards on a bottom hinge, and permit a current of air to circulate about the heads of the cows. The cows face these
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windows, which shed a good light into the byre. Another large window is at the gable end of the byre--that is, opposite the Blackman fan. This opens on a side hinge :throughout its whole length. There are, in addition, three roof lights. The division blocks have rounded corners, and the fireclay feeding-troughs have been so built that no crevices exist. The feeding-passage at the head of the cows is 3 feet wide. The channel behind the cows is 18 inches wide and 6 inches deep. The rear passage, again, is 5 feet wide. The cows are stalled in pairs, and have an abundance of space in which they may move or lie down. The drainage is perfect, and the dung-hea p is fully 50 yards away. A water-pipe with a thin hose attached to it has also been introduced into the byre. There is no attempt at artificial heating, nor wilt any be made. My difficulty is to keep the byre at 59° F. Improvements that could be suggested are windows on the north wall, but the presence of an engine-house precluded any windows on that side. Inlets of fresh air nearer the noses of the cows might have been inserted; but when I inform you that most of the improvements were carried out with a good-natured scepticism on the part of the cow-feederl and all expenses came out of his pocket, you can understand I dared not demand too much. For ~he same reason I could not ask for a lining of glazed bricks on the inside walls. In process of time I hope to see the walls painted, to a certain height at least, with white eolour. Lime-wash would be spoiled by the hose-pipe. There still remains one very important matter in byre construction seldom touched upon. I refer to the floor on which the animals lie. The hard floor is an objection, and tries the knees of Che animals. Tar macadam appeals to one as a likely substitute, but the heat of the animals' bodies would soften this, with disastrous results t6 the cow's hide, udder, and teats. An objection to this form of byre is that cows may push their heads over the trevass and soil their beds with droppings. The cow-feeder has, by an ingenious arrangement, fixed an iron rod from the one end division block to the other. This rod keeps the cows in their places, as they cannot push further forward than the rod. It is a simple but clever idea. No originality is claimed for the style of the byre, but we can say, in Paisley at least, that we have held other antiquated byres up for a ridiculous comparison. I refer to byres where the cow is fixed with her nose at the wall. A wider passage at the head would be urged by some, but even the wider passage would not obviate the evil that threatens the cows. I mean a constant indoor life can never approach the benefit that
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must follow an outdoor life--a life, let me say, that is peculiar to animals; a life that has been gifted to them by God, but which has been robbed from them by man in his desire to make money. I hope the time is not far distant when by some means or another dairy cows especially will be compulsorily tethered in open courts, as against hermetically closed byres. The ingenuity of man is not beyond erecting buildings ~hat will provide cows with a maximum of fresh air and light, and the needed shelter against inclement weather. Cows need no more. Some far-seeing and intelligent individuals have adopted such a system, and the day must come when such a principle will be universal. Just as we expect to curtail tubercular diseases by improved dwellings and open air-spaces, so must we eradicate tuberculosis in cattle by altering their modes of living. Tuberculin tells us that tubercular mischief is present, but there it stops, for we cannot, as matters stand, hope to advance much further. Compensation would be the sinking of thousands and thousands of pounds, for no sooner would the diseased animals be cleared out than another set would begin to pine in the dark, stuffy, and insanitary bytes that abound in the British Isles. If we were to construct a byre that would practically obviate the chance of tuberculosis, we should have the cows stalled as I have indicated--that is, in one row, and a feeding-passage at the head; a continuous series of windows from one end of the byre to the other behind the cows. Provision could be made for these windows to open to their full extent when the superintendent elected by choice or advice to do so. There would be no wall at the opposite side of the byre, that is, in front of the cows. Iron pillars at intervals would support the roof. In inclement weather, when the wind was sweeping into the byre through the pillars, straw matting could be suspended at intervals from pillar to pillar or throughout the entire length of the byre, to protect the animals. If Government would advance money to permit the universal construction of such by~?es, it would serve the end in view better by far than compensation. In support of such construction of bytes I have only to refer to the experiment made by Professor Axe, and gladly quoted i n this paper, and I humbly subscribe to Professor Axe's doctrine that fresh air, not cubic space in a closed-in byre, will obviate tubercular diseases in cattle. In that connection I might parenthetically remark that a cow-feeder will tell us that high-class cows will not do well in open byres. "Weeds" and other ills must follow in the wake of a cold byre. :But here again
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we must meet that argument by affirming that the life led by these cows has accustomed them to heat. Submit them to the opposite condition, and they will thrive better and last longer. It is all a question of custom. Less than ten years ago people supposed a case of pulmonary consumption should on no account be permitted out of doors on a cold day. The simile applies to the cow. Milk and money, however, are at the foundation of the housing of the cow question. Again, there are the North of Ireland cows. These do well and milk well, though grazed on the hillsides. Let us bring them into a byre, and they perform ~heir functions feebly. A knowledge of these minutia will convert one into thinkhlg that a trial of a different type of byte will find the cows, well-bred or crossbred, accustoming themselves in time to their cnew modes of living. Without going further into detail,let me quote to you one or two most convincing extracts from an exhaustively detailed report made by Professor Wortley Axe last year. Under the auspices of the :British Dairy Farmers' Association he was asked to carry out extensive experiments with tuberculin. Nine different herds were selected, containing 461 cows and 19 bulls. There were among these 335 shorthorns, 67 cross breeds, 47 Ayrshires, 3 Dutch, and 1 :Brittany. Now, for sake Of comparison, let me take four herds mentioned in the report. One herd is bad, the second good, and the third excellent ; the fourth is the type we see every day. Herd No. 1 eont~ained 86 cows, housed in a double shed. Each animal was allowed 500 cubic feet of air-space. Fresh cows were brought in from time to time and kept forward in flesh, and at the expiration of their milking periods sold fat to the butcher. Once in the shed, they were kept there until they ceased to give milk : 90 per cent. reacted to the tuberculin test. The cows looked so plump and well that several had ?so be slaughtered to convince the owner of the existence of tubercular disease. Herd No. 9~contained 76 Cows and 7 bulls. The animals led an outdoor life from May till November, and were allowed out during the winter for a short time each day. The sheds were low and primitive in character; they were open to the yard on One side. In winter the opening was partially closed by means of hurdles loosely drawn with straw. Only 8"6 per cent. reacted. I have italicized the word "primitive," as it has a most important bearing upon the point I want to bring out. The stock was not of the finest pedigree, but was useful for feeding and milking. On ~ha~ point the Royal Commission in 1898 made an important remark when i t said: "One serious
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feature in the distribution of this disease is its prevalence among high-class pedigree stock." In the words of Professor Axe, " T h i s is not due to a predisposition so much as the retention of valuable strains for long periods and for breeding purposes. Also the offspring of these valuable animals are subjected to more artificial treatment than ordinary animals." Herd No. 3 contained 41 cows. The animals were bred on the farm, and led an outdoor life night and day, summer and winter. The animals knew the byres at milking times, and only in very severe weather were driven in for shelter. Not one cow reacted to the test. Herd No. 4 comprised 59 cows and 1 bull. The cubic air-space was 596 feet per animal. In winter they were confined to the byre night and day ; in summer out at pasture. 76"9 per cent. reacted. These facts are worth volumes o~ dissertations upon tubercle bacilli; they must prevail some day. It rests with us to~ make them prevail. Those who adopt the open-air treatment of their cows declare--and I quote their own words from the report given at the t i m e - - " The shortage of milk is eeonpensated by the greater cleanliness qf the milk, the healthiness of the cows, and the less expense and trouble in looking after thenT." I sincerely wish cow-feeders would see the obvious reason in this. Now a point with reference to the udder. Of the 461 cows tested, 51, or 11 per cent., were found to have disease of the milkgland in one form or another: 55 per cent. of these glands were from animals that reacted to the test ; the other 45 per cent. were in the non-reacting animals. But the chief point worthy of remark is that tubercular affection of the udder was discovered to be very rare even in the reacting animals. It shows us how the appointment of a veterinary examining officer may, after all, be of little assistance. To prove his case he witl require to produce bacteriological and microscopical proof of the existence of bacilli from every udder he condemns. Even the response to the tuberculin test will not help him, for the tubercular mischief may be elsewhere than in the udder. Now, let me say a word about tuberculin, an agent~ that h a s been awarded as much praise as it has received abuse. The abuse has come from those who have been affected by the test; the prMse has come, and continues to come, from our leading veterinarians at home and abroad. The man with a filthy house is loudest in his condemnation of the dwelling next door, but when the first man's house is condemned he begins to miscall everyone. Many cow-feeders stand in an analogous position when we make tuber. culin the detective. In our experiment 17 cows were tested, and
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3 reacted. They were mostly cross-bred cows, which are less frequently tubercular than the better milking and higher-classed Ayrshire cow. The test was carefully carried out by the bm'gh veterinary inspector, and every detail as regards preliminary rest and taking of temperatures had attention. The charts indicate a rise in the reacting animals to 106° F. The tuberculin was procured from the Royal Veterinary College, and strict antiseptic precautions were used. In each of the reacting animals the temperature began to rise at the ninth hour, and continued till the fifteenth hour. The three reacting animals were slaughtered, and in every one was the tuberculin tesfi confirmed. In no instance could one say the disease was widespread. Subsequent to the testing I was informed that one cow had been tested three months before, and had reacted. She had failed to give a response to the detailed test, already referred to. The cow-feeder was willing to stake money on the fact that though she had shown a reaction three months ago, there would be no " ~ubers" found in her. I accepted his challenge, and the cow WaS led to the slaughter. I have reckoned her in m y original statement as one of the three. As I have already said, th~ cow showed tubercle, and proved tuberculin to be reliable; bug the very important fact was brought out that, contrary to what we, read, the tuberculin had provoked a long immunity. We are led to believe that a c o w may, wi¢h certain result, be retested in six weeks. This is a c a v e and a danger Signal. It means Chat the unscrupulous dealer:--and dealers of that type do exist--may sal~ animals that will defy any t~st save that of the microscope when the udder is affected: Moat of you were aware of the "salting," no doubt, but I dare say it is new to hear that the immunizingeffect can remain so long. Before proceeding further I might add that in six months agai~ we intend to have the cows retested. Lastly, let me attempt to summarize and answer the objections raised against tuberculin. One reason given to prove the fallibility of the test is that cows have reacted and yet have lived so well and so long that there could not have been tubercle present. People, w h o believe an argument such as that cannot be controverted. We have hundreds of instances of men and women who have beer~ told that they had nofii:~long to live because they were smitten with tubercular disease, yet they are alive and prospering. It would be, a pretty argument to conclude from that that there was never any tubercle present. Only the slaughter-house can settle that argument when applied to cows. Secondly, animals react, and a~ t h e slaughter-house give a negative result. This seems startling or~
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the face of it, but let us ask some questions. Who performed the test ? Was it a qualified person ? What was the temperature for two days prior to the application of the test ? What was the condition of the animal? What about parturition? Was it recent? Who performed the post-mortem ? Was every gland examined ? I leave these questions to be answered. It is strange that those of us who favour the test are willing to bring evidence of every kind to bear upon our research, but those who speak against tuberculin are content to make sweeping assertions, devoid of conclusive proof. When we know that a few isolated millet-seed deposits can yield a reaction, we can understand how an untutored eye, willing, perhaps, to be timorously blind, can overlook these tiny specks. An off-hand opinion of that kind is quite valueless. Let us take one sentence from Nocard's little book. From him we hear a different story. "Experiments made by thousands in all countries have shown that the ' lymph' of Koch, injected in small doses under the skin of cattle suspected of tuberculosis, sets up in tuberculous animals alone an intense febrile reaction, permitting one to assert the existence of lesions so minute that other methods of diagnosis (clinical or bacteriological examinations and inoculations) would be powerless to reveal their presence or even to make one suspect their existence." Nervous animals may be irritated or upset by the injection of tuberculin or the frequent insertions of the thermometer into the rectum, but a wise and careful veterinary surgeon will not jump to a hasty conclusion about such an animal should she show a rise in temperature. But instances such as that are quoted against tuberculin. The opponent of tuberculin views it as a wicked invention of a hysterical band of scientific men. There is the familiar argument that a cow may not react and yet will show diffused tuberculosis. The widespread existence of the disease is ?she reason for the imperfect reaction. The thermometer and general appearance of the animal will, however, guide a skilled veterinarian. It is given as an argument against tuberculin that it causes abortion, perhaps diarrhcea, and produces constitutional symptoms too n~merous to mention. Our leading authorities do quote~eases where tuberculin has produced these disorders, but they are frank when they make their admission. We know that diphtheria antitoxin can and does work wonders when given in big doses and early, but because it now and again is followed by urticaria, nervous symptoms, or rheumatic pains, it does not surely follow that antitoxin is a silly drug in the market. Just as antitoxin can be said to be a substance free from danger to the individual acted
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upon, so we can say tuberculin--and I make it emphatic, pure tuberculin--well and carefully injected, is a harmless agent. The most dangerous objection yet launched at tuberculin has been the latest. It is to the effect that the injection of this material produces tubercular disease--in other words, tuberculin is an infecting agent. This, to the layman, must be like a sparkling ray of golden hope. If any tuberculin does produce infection, then it ought to produce a lesion at the seat of puncture ; and if it can be proved that tuberculin has done so, then the only answer must be that there was something radically wrong in the manufacture of the tuberculin. Tuberculin is prepared in this way (Nocard) : " A culture on glycerine bouillon is incubated for six weeks at a temperature of 37 ° C. This is next sterilized in an autoclave at 110° C. ~ext it is concentrated in vacuo in the presence of sulphuric acid or in a water-bath until the culture is reduced in bulk to one-tenth of its original size. It is then filtered through germproof filters, and stored away from heat and light in hermetically closed vessels." If bacilli can come safely through so many ordeals, then our whole knowledge of the vitality of the Koch bacillus is utterly at fault. On the other hand, if no local lesion is found, and tuberculosis develops in a cow that did not react at the first test, the argument all inclines to show that the animal developed the diseasg in some other way. Bacillus-free tuberculin cannot, as far as bacteriology teaches, produce tuberculosis. Of course, if anyone wants to condemn tuberculin, it is easy to say tuberculin was the culprit that caused the diseased condition. The fourteen cows at present stalled in our byre will in course of time be sold. The cow-feeder expects them to go to the slaughterhouse; there I shall have a further opportunity to follow up the tuberculin investigations. I have communicated with :Professor MeFadyean of London and Professor Muir, Professor of Pathology, Glasgow University, with reference to this question of the infection by tuberculin. I have answers from both, with full authority to state that in their opinion infection is quite impossible if tbe tuberculin has been carefully prepared. They cannot speak for the tuberculin that is not got from standard makers. Some time ago Professor Delgpine~.:i~f Manchester made this point very clear.