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Agar plates at twenty-four hours (room temperature 33° C.) show numerous small brownish colonies. Anaerobic culture shows colonies similar to those seen on agar plates.

Slow leaker No. 4.-Small amount of dirty-yellow juice; meat dark throughout and tends to fall apart readily; sour odor; fat soft and pasty; interior of can shows evidences of corrosion.

Agar plates at twenty-four hours (room temperature 33° C.) show welldeveloped circular and oval colonies of a dark-brown color. Anaerobic culture shows similar colonies.

Slow leaker No. 5.-Considerable turbid, dirty-yellow fluid; meat darker than normal and falls apart readily; slight, but distinct putrid odor; fat soft and pasty; interior of can shows evidences of corrosion.

Agar plates at twenty-four hours (room temperature 33° C.) show no apparent growth, but at four days (room temperature 33°-36° C.) show several spreading brownish colonies. Anaerobic culture at four days shows a number of well-developed circular and oval colonies.

Slow leaker No. 6.-Considerable yellow turbid fluid; meat dark and falls apart readily; sour odor; fat soft and pasty; interior of can corroded.

Agar plates at twenty-four hours show no apparent growth; at four days (room temperature 33°-36° C.) show no colonies of bacteria, but one or two colonies of mold. Anaerobic culture at four days shows no growth.

Slow leaker No. 7.-Considerable turbid, milky fluid; meat darker than normal and tends to fall apart readily; sour odor; fat broken down; interior of can corroded.

Agar plates at twenty-four hours (room temperature 33° C.) show a few well-developed, brownish, spreading colonies with dark-brown oval centers, also a few pale-brown spreading colonies. Anaerobic cultures show a few circular and oval colonies, which appear white to the eye and dark brown under the low power of the microscope.

Slow leaker No. 8.-Considerable turbid, gray fluid; meat darker than normal; sour odor; interior of can shows evidences of corrosion.

Agar plates show no apparent growth after two days at room temperature (33°-36° C.). Anaerobic culture same as agar plates.

Slow leaker No. 9.-Considerable yellowish juice; meat very dark; wellmarked sour odor; fat soft and pasty; interior of can corroded.

Agar plates at twenty-four hours (room temperature 33°-36° C.) show enormous numbers of small, irregular oval or circular brownish colonies. Anaerobic culture shows similar colonies.

Slow leaker No. 10.-Small amount of turbid yellow fluid; meat darker than normal; distinct sour odor; fat soft and pasty; interior of can corroded.

Agar plates at twenty-four hours show no apparent growth, but at three days (room temperature 33°-36° C.) show one or two spreading white colonies. Anaerobic culture at three days shows no apparent growth.

RESULTS OF EXAMINATION OF SOUND CANS.

The results of the examination of the five sound cans were as below: Sound can No. 1.-No loose tin; sides are tight and well concaved, showing good vacuum; small amount of thin yellowish juice on opening can; meat shows a good bright color throughout and gives the normal odor of corned beef; fat firm and of a good yellow color; when can is inverted the contents hold together and retain shape of can; interior of can smooth, in places the tin has a tarnished appearance but shows no evidences of corrosion. Agar plates and anaerobic cultures negative.

Sound can No. 2.-Contents same as can No. 1. cultures negative.

Agar plates and anaerobic

Sound can No. 3.-Contents same as can No. 1. Agar plates and anaerobic

cultures negative.

Sound can No. 4.-Contents same as can No. 1. cultures negative.

Sound can No. 5.-Contents same as can No. 1. cultures negative.

Agar plates and anaerobic

Agar plates and anaerobic

SUMMARY OF BACTERIOLOGICAL FINDINGS.

Of the ten slow leakers which were examined bacteriologically seven showed bacteria, two showed molds, and one showed no growth. In other words, 70 per cent showed bacteria, 20 per cent showed molds, and 10 per cent showed no growth. In the case of the sound cans, on the other hand, agar plates and anaerobic cultures on glucose agar failed to reveal bacteria in a single instance.

The fact that three of the slow-leaking cans failed to show bacteria does not necessarily indicate that these cans were free from bacteria, for they may have contained only a few bacteria so located that they were not encountered in taking out portions for cultures. When bacteria gain entrance to a can it must require some time, of course, for them to multiply and become disseminated throughout the contents of the can, the length of time required depending upon the temperature and other conditions, and it is possible that in the cans in question this had not taken place.

The absence of bacteria from the sound cans would indicate that the bacteria in the slow-leaking cans gained entrance to these cans from the outside through leaks or defects in the tins and were not present in the cans immediately after processing. This is also borne out by the fact that all of the bacteria found in the slow-leaking cans, with one exception, were nonspore-bearing organisms which would, in all probability, have been killed by the temperature to which the cans were submitted in processing.

The bacteria which developed in the cultures made from the slowleaking cans were isolated and grown on the different laboratory media. A number of different organisms were found, both micrococci and bacilli. Among the latter were Bacillus subtilis, B. proteus vulgaris, B. coli communis and a paracolon bacillus. Micrococci were found in all save one of the cans examined and when grown on the different laboratory media were found to correspond with Staphylococcus pyogenes albus and citreus.

No obligate anaerobes (organisms growing only in the absence of oxygen) were found in any of the cans; the organisms obtained from the anaerobic cultures were found upon examination to be the same as the aerobic growths, or, in other words, all of the organisms iso

lated were optional anaerobes (i. e., organisms which grow almost as well without oxygen as with it).

All of the organisms found in the slow-leaking cans produced an acid reaction when grown in glucose bouillon and litmus milk, and the corrosion of the interiors of the cans was evidently due to the action of acids produced by the bacteria growing in the meat. The absence of corrosion in the sound cans indicates that under normal conditions the meat juices had no corrosive action on the tin.

While the bacterial forms found in the slow-leaking cans are not usually pathogenic, they may at times possess pathogenic properties, and some of them are capable of elaborating metabolic products of a toxic nature.

In view of the possible formation of toxic products in slow-leaking cans, the final inspection of all cans prior to shipment becomes an important point and one which should be carried out in order to safeguard the public. If this final inspection is not made, it would be possible for a slow-leaking can which had not begun to swell and in which only slight putrefactive changes had taken place to reach the consumer. The changes in such a can might be so slight as to escape the notice of the consumer, and yet the contents of the can, if eaten, might be capable of producing disastrous results, because of ptomaines or tox-albumins resulting from the growth of putrefactive organisms.

CONCLUSIONS.

1. The majority of slow-leaking cans contain bacteria, which invariably set up putrefactive or fermentative changes in the contents of the cans.

2. The majority of slow-leaking cans, when incubated for ten days at a temperature of 100° to 110° F., will develop into "swellers." 3. Short-vacuum, overstuffed, and collapsed cans will not swell upon incubation provided there are no breaks in the tins.

4. The swelling of slow-leaking cans upon incubation is due to the formation of gases resulting from the growth of bacteria within the

cans.

5. The product contained in slow-leaking cans is not a safe article for food even though it be reprocessed.

THE DEHORNING OF CATTLE.

By RICHARD W. HICKMAN, V. M. D.,
Chief of the Quarantine Division.

The frequent inquiries received by this Bureau for information concerning the dehorning of cattle and the means used for their control during the dehorning operation, also concerning the proper method of treating calves to prevent their horns from growing, have prompted the writing of this article. The writer will endeavor to present the subject in the most practical manner for the guidance of the dairy farmer or other cattle owner who may be in quest of this information; first describing the operation as universally practiced in the East prior to the introduction of the dehorning instrument or dehorning knife and as practiced on his own herd in Orange County, N. Y., in the late nineties, where the old-fashioned board stanchions were and still are in use to a considerable extent. Dehorning by means of an instrument, also the prevention of growth of horns on young calves, will be described later.

DEHORNING BY SNUBBING HEAD TO STANCHION RAIL.

The dehorning of partly developed and adult cattle can be very satisfactorily performed without other apparatus or instruments than a good strong clothesline and a clean, sharp meat saw-or a miter saw with a rigid back-in the hands of a fairly good mechanic. The same simple means for controlling the animal is just as applicable when the dehorning knife is to be used as when the horns are to be removed with the saw. This consists in securing the head of the animal to the horizontal rail or stringpiece which holds the upper ends of the stanchion boards. The animal is put in the stanchion in the usual manner; then one end of a heavy clothesline is passed around the upper part of the neck and tied in a knot that will not slip, otherwise it will choke the animal. The free end of the rope is now carried between the horns, through the stanchion to the front, up and over the horizontal stanchion rail, then down underneath the neck and up and over the top of the stanchion rail to an assistant, who should hold it firmly. Now release the stanchion, allowing the animal to withdraw its head, so that the horns are just inside of the stanchion rail or stringpiece; then, keeping the rope tight, pass it once around

the muzzle, up and over the stanchion rail, and through to the front again to the hands of the assistant, who should stand 3 or 4 feet in front of the animal and hold the rope firmly, but prepared to release it when told to do so by the operator. The animal is now ready for the dehorning operation.

It is necessary that the rope be held by an assistant, as in the event of the animal struggling during the operation so as to throw itself off its feet, or if there appears to be danger of its choking, the rope may be slackened promptly at the word of the operator and the animal partly released. This, however, is rarely necessary, for as soon as the head is secured the operator should be ready, standing at the right shoulder of the animal with his saw, and proceed to saw offfirst the right and then the left horn. The horns should be severed

[graphic]

FIG. 47.-Dehorning with saw, cow's head snubbed to stanchion rail.

at a point from a quarter to a half inch below where the skin joins the base of the horn, cutting from the back toward the front. Figure 47 shows the animal and the operator in position for the dehorning operation by this method. It is a good plan before commencing the real work to experiment upon an animal in the matter of control by snubbing the head to the stanchion rail as described.

If the stanchion rail is too wide to permit of properly securing the lower part as well as the upper part of the animal's head, the turn of the rope around the muzzle may be omitted and the last lap of the rope carried around the stanchion rail to the front and to the hands of the assistant. The rope should pass each time over the neck of the animal to the stanchion rail so that the laps are between the horns, in order that the rope may not interfere with the work of the saw.

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