AILMENTS OF COWS

Waikato Times, Volume 127, Issue 21199, 23 August 1940, Page 16 (Supplement)

AILMENTS OF COWS

Necessary Precautions . MILK FEVER AND GRASS STAGGERS Care at Calving Time. Calving is now taking place in Waikato dairy herds and every farmer must be on his guard against the danger arising from milk fever. Carelessness may result in the loss of highproducing animals, while a little forethought and care will guarantee producers against costly losses. With a smaller dairy cow population than last year, every cow is needed in the national drive for increased production and where farm management is of a high standard there will be no great losses from such seasonal diseases as milk fever. Grass staggers is another dairy cow ailment that must be guarded against by Waikato farmers. Milk-fever is a disease associated with parturition, and typically occurs within 48 or 72 hours of that event—occasionally just as parturition is about to occur, and rarely at from a week to a month later. It is a disease of the mature cow, rare in second calvers, and unknown in heifers. Similarly, it is seen chiefly in the high producing animals. High condition is a predisposing factor. Many theories, such as the formation of toxins in the udder or uterus, anaemia of the brain, and a lowered sugar content of the blood, have been put forward from time to time and then abandoned. While a complete explanation is still lacking, the work of Dryene and Greig, then of the Royal Dick Veterinary College, Edinburgh, enabled them to put forward the most satisfactory theory to date. Drop In Calcium They have shown that in milk-feyer cases there is a sudden marked drop in the calcium content of the blood, this returning to normal as recovery is brought about. In the animal body mechanism exists which normally should ensure that the calcium removed from the blood at the commencement of lactation to supply the colostrum and the milk is simultaneously restored by withdrawals from the stores in the bones. The percentage of calcium in milk is about ioz per gallon, proportionately higher in colostrum. The strain on this mechanism is thus highest in the best producing cows When it fails the blood calcium falls and symptoms of milk-fever appear.. It is evident, however, that there are certain practical points having an important bearing on the occurrence of milkfever. It has frequently been noted, and it is known to many farmers that milk-fever is. more prevalent in a “grassy” season that in a season when green feed is scarce, and also that where cows are calved off rather hard, dry pastures with a hay ration there is less milk-fever than where they are brought into green flushing paddocks for two or three weeks before calving. The latter practice is sometimes adopted to ensure that the bowels are in a laxative state before calving, but this end could probably be better attained by the use of ensilage, molasses in hay, or drenching. Change in Green Feed Dr. Hopkirk s work with sheep seems to indicate that the change on to the green feed has some depressing effect on the amount of the general minerals bases of the blood. The first thing noted is usually a stilted, staggering gait, and animal is unwilling to move. As a rule, the general ner-

vous disturbance and the acutely sensitive and easily startled condition present in grass staggers is absent. In exceptional cases which are known to suffer from milk-fever and low calcium there may be a stage of marked excitement, and struggling when the animal goes down. In the typical case, once the animal goes down, which, may be two or three hours after staggering is noted, she rather quickly becomes quiet and dull, with the breathing easy and regular, and with a tendency to throw the head around on to the ribs. The temperature is usually well below the normal level of 101.5 degrees, and may be 100 degrees, 98 degrees or lower. The pulse rate is usually about 60. While veterinary aid is always desirable, under the present conditions it is frequently unobtainable. Prompt measures are necessary, so that the owner must usually act at once. Although certain other disease conditions, such as fatty degeneration of liver, acetonemia and, according to American writers, septic absorption from uterus, may occasionally produce similar symptoms, all animals showing the signs outlined above within 48 or 72 hours of calving should at once be treated for milk-fever. The treatment adopted must depend on the stage of the disease. Where the cow is still on her feet staggering a calcium drench carefully given will often prevent further development. Such a drench would be : Calcium chloride 2ozs. molasses 2-31bs., water 1J pints. Another Successful Drench Another drench used successfully by Dr. Annett, of Matangi, is made by stirring 1 pint of molasses in 1 quart of boiling water, then Jib. of hydrated lime, filter through muslin when cool. This mixture will keep some weeks if bottled. Once the animal goes down inflation of the udder must be done. The main essentials are a simple outfit properly sterilised, strict cleanliness of the udder and teats, and inflation until the udder is tight. It is very important that as soon as the udder is inflated the cow should be rolled up on to her brisket and maintained in a sitting posture with sacks of earth. Where the animal is found flat out and paunch is badly bloated, she should be rolled into a sitting position for a few minutes before inflation is carried out, as this will relieve the bloat and do away with any need for tapping. The calcium drench may be given while the cow is down, if she is able to swallow. There is always a risk of the drench going into the lungs if it is given while she is half-conscious, and no animal in a comatose state should be drenched. Should the response not be satisfactory within a few hours, the calcium and molasses may be repeated, together with a stimulant dose of 3 drams of carbonate of ammonia and 2 drams of powdered nux vomica. The carbonate of ammonia and nux vomica may be repeated with molasses twice daily. Should there be any constipation, an enema of soapy water should be given and the amount of molasses increased. Care in Drenching

Care in drenching must be stressed. Septic pneumonia is one of the commonest causes of death in milk-fever, either from the entry of foodstuffs into the lungs when the cow is down flat or from faulty drenching. Avoid flushing the cows with green feed before calving. The old advice to keep the cow on a bare paddock for a few days before calving still holds good. Take every means of increasing the mineral reserves of the cows prior to calving, using licks containing either dolomite or steamed bone-flour. The addition of* cod-liver oil is believed to aid assimilation of calcium. Burnt lime, chalk, or finely ground carbonate of lime should be added to the drinking water. Lucerne hay or hay containing a good percentage of cow grass or clover increases lime content of the diet. Where numerous cases are occurring a calcium drench should be given to each cow immediately after calving. This should be done in any case with any high producing cows which are known to be susceptible to milk-fever, particularly if they are in high condition.