HERD TESTING

Timaru Herald, Volume CXXXIII, Issue 18761, 27 December 1930, Page 10

HERD TESTING

A NECESSARY SYSTEM. THE WAY TO SUCCESS. Herd testing, if properly carried out, is the quickest and surest way of getting together a good dairy herd; but otherwise it is w r orse than useless, as a dairyman can easily get rid of his best cow if he judges her by one test. The fat content is the most variable of all the milk constitutents, being influenced by her nerves. Fear, excitement, change in the weather, torment by flies, a rough or strange dog or milker, and sickness all tend to cause the butter-fat to increase or decrease. Usually the heat or excitement or the fever from pain or sickness will increase the but-ter-fat while is lasts; but the decrease will be greater and w r ill last longer till her her nerves are settled again or her body has recovered from the strain. So rough treatment or neglect brings loss to the farmer.

Those who feed their cows well and see that they have abundance of good water, shade, and shelter, and treat them kindly, will get the highest results from their dairy, states an exchange. Another mistake made by farmers is in thinking that the test is all that matters, and so they do not take the trouble to weigh the milk. They say, “This cow is not profitable. She tested only 2.5 per cent., while this one tested 6 per cent.” But if the former gave 601 b. of milk daily for one week she would yield 10.51 b of butterfat and more than enough milk to feed her own calf. If the latter gave only 101 b of milk daily for a week she would yield 4.21 bof butter-fat, with not enough milk to feed her own calf. The milk of each cow should be weighed and tested once every 28 days for nine months (or seven months if they are only milked for that time). When a cow first comes in her milk is poorer in fat than when she is drying off. As the quality of milk decreases the percentage of fat increases, and the cow, starting the season giving up to 601 b of milk per day with a 2.5 or 3 per cent, test, may end the season In giving 61b of milk per day with 7 p£r cent, or even higher test. Milk and cream want more care than almost anything else, because they will absorb any odour, good or bad. They are the best media for all kinds of bacteria, except one water type. Milk cleanly drawn from healthy cows in clean surroundings will keep at ordinary temperature for 60 hours. Bacteria are minute bodies consisting of a single cell. It was formerly thought that they belonged entirely to the lowest order of the vegetable kingdom; but Professor Jensen in his latest research finds that as well as protoplasm, which is the living substance of plants, some kinds contain a substance called musin, which belongs to the lowest order of the animal kingdom, along with crayfish, insects, etc., some of which are endowed with motion. They reproduce by fission; that is, the cell divides and two exist where there was but one before. Some kinds (such as odium lactis, one of the air germs) are known to divide every 20 minutes, which explains why milk so quickly deteriorates. All require liquid or semiliquid media for growth and development; but many kinds can exist in dry conditions for long periods of time. They are carried about in the air, especially when accompanied by dust into every rough place, corner, or seam of buckets, strainers, cans and separators; in fact, wherever a particle of milk may lodge. They are widely distributed through Nature, and are found in every stream and river on the face of the earth. By far the greatest number, however, are not only harmless, but positively beneficial. Other kinds are the cause of illness and disease, flies being one of the most prolific carriers, bringing them from any filth they light upon. They drop into milk or food, or feed round the edges, thus contaminating it. Some kinds are able to assume the spore form. They are then inactive, but are able to resist greater extremes of heat, cold and desiccation. As soon as conditions again become favourable they re-geririinate, and the vital process is resumed. The germ most common in milk is the lactic acid germ, which feeds on the natural sugar, turning the milk sour. It thrives best at temperatures from 70 to 100 degrees Fahr. It is not harmful (on the contrary it is most beneficial), and no other germ will thrive in the presence of pure lactic acid; but the pseudogerm also forms lactic acid, and is one of the worst troubles in the cream.