Rensselaer Union, Volume 10, Number 36, Rensselaer, Jasper County, 23 May 1878 — Why Cows Hold Up Their Milk. [ARTICLE]

Why Cows Hold Up Their Milk.

The bag or udder is divided into four parts, entirely distinct from each other, except as they are held together by membraneous ligaments. The milk in each is held in confluent tubes, which, like the roots of a tree, are all concen. trated into one just above the teat, the milk entering that funnel-shaped organ by a single channel. Just at the upper end of tne teat the; walls of this channel are contracted and the contraction is surrounded by a band of muscular fibers. The will of the cow can operate on this band, contracting or expanding it at pleasure, making it operate like a valve. At the junction of each smaller tube with a larger one is A similar contraction and band, also under the control of the will. Ordinarily these bands are contracted (as in the neck of the bladder) so that the milk has to crowd its way through them to get from the smaller into the larger tubes. This is an admirable arrangement for sustaining the weight of tne milk equally in ell parts of the udder and preventing it from pressing heavily upon the teats. When the udder is full, if the milk is drawn out of the teats, relieving the pressure in them it requires a vigorous effort of the will of the cow to prevent the pressure above from crowding the milk down to fill the vacancy, u the udder is only partly filled she can hold the milk back more easily, and the less t here is in it the more easily can she maintain the tension of the” muscular bands necessary to prevent entirely the milk from flowing through them. Wlrmthe milker first takes hold of the teats anil begins to milk the excitement causes the cow to contract the bands so firmly asto hold back the milk perfectly for a time. But presently this vigorous contraction will begin to slacken and the milk will pour through, and if all is quiet sho will relax the bands fully, when the milk settles down upon the teats, and if quickly drawn it can all be milked out to the very last drop, But this perfect relaxation will only last for a short time. If the milk is not soon extfaoted she will begin to tighten up the muscular bands again, mid the last part will be held back and permanently retained when the milker probably thinks he has got it all, bCChuse it stops coming. A cow should, therefore, be milked quickly ns well as quietly. A ealf .will draw- milk in three minutes, and a milker should come as near that time ns possible. If the time of milking is tnuen prolonged she will become Impatient,, and be Sure not toj "glVedown” perfectly. The quietest find quickest milker gets the most and best milk, Because die gets (all the “ strippings,which are the richest 'part.— N i. Herald.