STRINGY OR ROPY CREAM.

Otago Witness, Issue 2665, 12 April 1905, Page 6

STRINGY OR ROPY CREAM.

j Notwithstanding the f.ict tl.at the subject is ore v hich many of our hading" dairy scientists have, with a lar^e nuasure \ of stJ&osss. devoted much labour to investii gate, the origin of stringy milk or cream, remains to the majority of dairymen moie or less a mystery. Needless to say, numerous theories have been advanced to explain the origin of the defect, but all properly conducted investigations into the matter go to f-hovr that in nearly every case. bacteria are the immediate cause. In all, it may be said i that, up to the present time, no less than { 20 different micro-organisms have been ! isolated and described which possess the I property of rendering milk viscous. To accomplish this the exact role played ! by these bacteria is not as yet well j understood, and it is probable different j species act in different manners. Some ! are known to concentrate their energies on. I the milk-sugar, which they decompose, forming a slimy compound. Others donot seem to set up any decomposition whatever of the milk constituents, and j microscopial examination of the infected milk in that case reveals the presence of 1 organisms clustering together in enormous | numbers, and forming slimy masses, which j alone are sufficient to . account for the | stringiness. Again, while some species , render the milk slimy in their early j growth, others do so only after several days, and some there are, which, first I of all, coagulate the milk, and then dis- ! solve the curd, forming a slimy solution. Water may first of all be mentioned as a source of stringy milk bacteria. There are several sources from which these bacteria may gain access to water, but they generally come from sewerage matter which is allowed to run into the stream,, or they may -originate from the droppings of cows which get into a stream of water. Now it has been proved that the mere drinking by a cow of such water will not render her milk stringy, for the simple reason that the bacteria which are taken in with the water are arrested in their progress through the digestive system, and cannot enter the mammary glands. But, in hot weather especially, cows are particularly fond of getting into a stream, splashing the muddy water about their bodies. This dirty water, containing innumerable bacteria, of the most injurious description, soon becomes dried, and adheres to the cows' bodies in the form of a fine dust, with the inevitable result that, in the process of milking, this dust becomes readily detached, and. fallinginto the milk, contaminates it. And if it should happen that by chance the particular organs of stringy milk are absent from this dust, others, perhaps, even more injurious tc milk and its products, and possibly the pathogenic germs, may be present. Mud on the sides of streams, or in ponds, causes contamination of the milk in much the same manner as polluted water does. Field ponds, especially when they are drying in summer, form a frequent source of milk contamination, and milking cows should be prevented from entering them.

The fact that Guillebean's bacteria have b&en found in the milk of cows affected with inflammation, of the udder points to the advisability of rejecting all milk from, cows so affected, no matter how slight the symptoms of disease may be, and her© it must be pointed out that bacteria, associated with the disease make their appearance in the milk before any external symptoms of derangement of "the milk glands are evident.

A noted authority on the subject, in his published essay, strongly urges on the attention of dairying farmers the following among numerous other causes for ropiness in milk : — 1. The air of dairies in which the drains are out of order has been found responsible for some cases of stringymilk. A dairy ought never to have anyinternal communication with drains, but where this arrangement unfortunately exists, every precaution must be taken to keep the drains in thorough workingorder, and to well flush them regularly. It is also advisable in such cases to pour down each drain daily a quantity of solution of some effective disinfectant and deodoriser, such as Condy's fluid (permanganate of soda). 2. In my opinion the use of improperly cleaned milk utensils, or such as are out of repair, is responsible for the great majority of cases of stringy milk. The proper cleaning of dairy utensils is a matter which has been urged times without number in these columns : and a person who cannot be trusted to properly cleanse a milk pail ought not to be allowed to enter a dairy. In cases where stringy milk and other milk taints

crop up, special care should be taken

to thoroughly sterilise, by washing with the aid of soda, steaming and scalding every corner of every utensil in which milk is placed. The utensils should be subjected to a close examination to make sure that there are no holes or cracks in which milk can lodge unnoticed ; and any defect should be at once remedied. The writer once traced a bad case of stringy milk to the use of a milk churn which' had a very little of the solder which fixed the gauge inside eaten away, presenting a number of minute holes, jus& large enough to admit a pin point. On the gauge being torn off, there was found adhering to its under surface a

The Imperial Bitvss Spe*.t Pump: With Stream and Fine Spray Nozzle. — Made cj American noted manufacturers. Aie ob'auiable from Niiimo and Blair, Dtinedir. Frillsgrowers and Orcuardists should use them.

vile mass of slimy material (no doubt

decomposed milk), which literally teemed with bacteria of all descriptions. On having this churn repaired, the difficulty •with the milk at once disappeared. Wooden milk utensils, after having been used for some years, are very liable to get out of repair, besides being difficult to keep sweet. These demand special attention in case of milk faults, and metal .utensils are much to be preferred. 3. When stringy milk makes its appearance in a dairy, the dairy itself, and also the cow house, shotild be subjected to a thorough cleaning and disinfection. The floors and shelves and the stalls of the byre should be thoroughly scrubbed with boiling water, and the walls and

ceiling lhnewashed, and subsequently

kept in a state of thorough cleajiliness.

Dirty handling of the milk in any shape or fprm will, if it does not cause stringiness, contaminate, the milk in some way or another. The milking should always be conducted in a~ proper manner. The cows should be milked in a clean byre, or in a- clean part of the field. The udders should be bathed' in clean water, and the milkers themselves should go to work with newly washed hands and arms and •fidth clean clothes.

Peculiarity in the feeding of the cows is frequently put forward as a probable cause of stringy milk. On this head, Professor Jas. M'Creath, in his essay, already quoted, has the following : —

Personally, I have never seen a single case of stringy milk which could be traced to this cause ; but, nevertheless, it might be well to inquire into this point where search in other directions Jail, and a practical and decisive method of investigation would be as follows : Procure as many bottles as there are cows in the Jierd, and have them properly cleaned. Then draw the milk from each quarter of eveiy cow into the bottles, placing the milk of each cow in a separate bottle, properly labelled. Set the bottles aside in a warm place for about a day, and then test them one

by one for stringiness. The result of this simple experiment will give valuable information on several points. If feeding be the cause of the dairy milk becoming stringy, it should also cause each and all of the samples to become so ; for if the cows were all ti eated to

similar food, that food would, it might

fairly be assumed, have a similar effect upon the milk secreted by every animal in the herd. If, therefore, the milk in every bottle shows stringiness, some peculiarity in the feeding will, in all probability, be the cause of the fault, and must, therefore, bs altered in some •way. If it should happen that only

one or two of the samples should become

stringy, it would be reasonable to infer that the fault was due in some way to the animals which produced these samples, and would, most probably, be found to be owing to disease of tbe udder or some other derangement in these cases. But, should none of the samples become stringy, while at the same time the milk in the dairy became so, the fault is then obviously due to the mismanagement of the milk after it is drawn and brought into the daily; this

I have already gone into.

Another possible cause of stringy milk is in the presence in the pasture in which the cows graze", of a herb known as butter•wort. This plant is a small perennial with a rosette of leaves growing close to the .ground, from which arises a slender stem with a single violet flower. No doubt niillc can be rendered stringy by stirring the stem or leaves -of this plant in it, but experts say tfhat it must be very abundant — more so than it generally is in ordinary cow pastures — and that a lot of it must be eaten by the cows before it can produce this remarkable effect upon the milk.