ON THE LAND

Taranaki Daily News, 11 June 1930, Page 19

ON THE LAND

HANDLING OF THE HEIFER. CAREFUL TREATMENT NEEDED. The heifer during her first-calf period requires careful handling and feeding, wrties an Australian stock expert. Any rough treatment and careless management will result in impairing her subsequent usefulness. Heifers should be milked as long as possible. Even if the young cow is only giving a small.quantity of milk an 611011; must be made to keep her going. If she dries up too soon it is fatal, for at each future lactation she will tend to dry off at a similar period. A heifer should be kept going; it induces milk staying powers. Do not condemn a heifer on first calf that is disappointing in the quantity of milk, provided she milks for a reasonable period, is the advice of an authority of high standing. Many young cows improve greatly on subsequent calvings, 'but heifers that dry off too quickly are not' as a rule, worth persevering with. Keep a record of the heifer’s production by having her tested, as a heifer’s test is he'r life’s test. She will not materially- improve in the percentage of fat in after life, provided that when the test was taken she tfas in normal health and sufficiently fed. All increase in fat production will come from increased quantity of milk. DAIRY COW DISEASES. RESEARCH WORK RESULTS. Several officers of the New Zealand Agricultural Department are permanently engaged both in the field and in the laboratory on research in connection with the diseases of dairy cows in the Dominion. Recently a report was issued on the results of this work. Three diseases are discussed, two of them being well known all over the world for jnany years —namely, contagious abortion and contagious mastitis—and . the third, known as “return to the bull” or “temporary sterility.” Dr. Gilruth, and associated with him Dr. Reakes and Mr. H. A. Reid, have all done considerable work on contagious abortion and on mastitis, but, although they have helped to throw more light on these diseases, they have not had better results with treatment than Continental workers. On account of the very great ’losses associated with dairy cow diseases, and the necessity, for economical reasons, to increase dairy produce from this country, a further effort by a team of workers has been for some time in progress, in an attempt to find definite curative and preventative measures for combating the three major diseases. The team is composed of four veterinarians, Messrs, Dayus and Webster in the field, and Messrs. Hopkirk and Gill in the laboratory, with the help of field officers in general and of the chemical laboratory for the analysis of i pastures. It is from this team that the report quoted emanates.

Inflammation of the udder, or contagious mastitis: Known to the farmers as contagions mammitis, and at one time differentiated from a non-contagi-ous form. This latter differentiation no longer exists, and the point requires stressing that all mastitis must he looked upon in the herd as contagious. Mastitis is a localised disease of one or more quarters of the udder and it increased considerably after the introduction of the milking machine. Tlie method of infection is the biggest problem in mastitis. How, when and why does the germ reach and attack the udder tissue? The authors of the report have tried various methods of artificial infection without’ much effect. No results have been obtained by milking with hands washed in affected milk, or by leaving affected udder secretion on the ends of the teats over a period of a week on a number of cows. Injection of germs into the uterus of a recently-calved cow proved ineffective.

The only method left to produce mastitis experimentally is to introduce the organism into tho teat sinus. Not only must the organism be introduced, but one also requires that the organism be of a definite type, or that injury of the quarter also exists to produce a lasting ■inflammation.

How infection takes place cannot ■be stated at present. It may under exceptional circumstances be blood borrte in septicaemic conditions, 1 but such cases must be rare. Infection, apaprently, is usual through tho teat orifice. Experiments show that if only a very small number of organisms gain entrance, it may take five days to show up. On the other hand a massive infection or an infection with a more virulent type may show up in a few hours. Assuming the quarter is in a fit state of debilitation to become infected, what chance has the organism of gaining entrance through a tight sphineter muscle opening in the teat, particularly in a liand-milked herd? For milking machines there is a tendency, very • possibly, especially when the pressure is in the vicinity of 171 b, for a slight back suction. into, the teat to take place, and . if this occurs one can understand why machines are so great a ’danger where mastitis exists in a herd. Experimentally this point is difficult to prove, though at the first opportunity a trial will be made. With high machine pressure it is known that quite a numbei* of cases may result in a herd. Frequently the departmental officers may hear of some 20 cases occurring over night when r<ces or holidays have caused a careless use of the machines; friction gives the injury, the germs present in the machine from- chronic cases provide the organism.

OX, OR WARBLE FLY. REAsS SURIN G STATEM EN T. Alarm ha.s been felt in country districts at tho reported presence of “warbles” in New Zealand, and a reassuring statement is issued by the Department of Agriculture. The “warble” fly grub is well-knorvn in Britain, in Europe, and in Canada, but has never become domiciled in South Africa, Australia or New Zealand, and an official statement is that the Dominion is safe from the pest, as. experience has proved that conditions here are not suitable. In the disease, small, rounded swellings appear immediately under tho skin on the back of cattle, on either side of the spine. Each of these contains a grub which are the larvae of the ox, or -warble, fly. When tlie grub has fully developed, a small opefiiiig 'appears "frr 'the Wiling and the grub falls to tho ground.

where, if conditions are suitable, it hatches into a fly within six weeks. However, in New Zealand the conditions have always proved adverse to the grubs. The presence of these swellings under the skin seriously damages the hide of the animal and affects its commercial value. The Dominion’s safety is due to the fact that grubs leave the animal at the wrong time of the year (the disease can be found only in imported stock) and therefore die.

However, the department has laid down a procedure for treatment of the disease which is effective. The egg and grub are upon the animal for eight months. Hence, a system of quarantine, unless of great length and heavy exense, will not ensure the grubs not entering the country. The period of detention is, however, lengthened when the grubs make their appearance upon the animal while it is in quarantine.

Stock which leaves quarantine without exhibiting any symptoms of the disease is also kept under observation by the district inspector of stock and if any symptoms appear steps are taken to destroy the grubs before they become free. This is continued until a long enough time has elapsed for any warbles to have appeared upon the beast.

The grubs, once they reach their final stage, are easily destroyed by being squeezed out of the small aperture at the top of the. swelling and killed. This, states the department, is the surest way of dealing with them. Fresh swellings may appear over a period of months, so a watch must be kept. Other methods of treatment are to inject into the openings one of several preparations; Derris powder, in the proportion of one ounce to a pint ‘of water, well shaken up, and a 1 in 20 solution, in water, of silver nitrate. Another method is to plug the aperture with mercurised ointment, but squeezing out is the soundest way.

EARLY BREEDING. TESTS WITH HEIFERS. That many dairy heifers are bred to freshen at too young an age, with a constant tendency to check the growth of the individual, was the conclusion arrived at in an experiment conducted by the Missouri Experimental Station last year. The trial included 70 Jerseys and 25 Friesian heifers. Jerseys calving under 20 months of age averaged 207 pound of butter-fat during the first three lactations, while animals of similar breeding, but freshening 24 and 30 months old, had an average of 2601 b for the first three years. This represents a difference of 531 b of fat each year. When only the first three lactations aro considered, it means a goodly income for the extra months the heifers were dry. That is not all. When mature, the heifers which were bred later had larger capacity, and could consume larger amounts of roughages. This assures a lower cost of production, as digestible nutrients can be supplied more economically in roughages than in concentrates. Similar results were obtained with Friesians.