Of Concern to Dairymen

Manawatu Times, Volume 60, Issue 175, 27 July 1935, Page 12

Of Concern to Dairymen

A pcamphlct issued by Pennsylvania University of U.S.A., •written by Dr. George 11. Conn, D.V.M., 8.5.A.11., has caused “Observer” a considerable amount of thought. The author is held in high repute, amongst experts the world over. His arguments strike the reader as being singularly free of pre-judg-ment. The greater part of them are applicable to New Zealand dairy practice. This authority holds that a very large proportion of abortions arise from faulty nutrition. ' The final paragraph of his pamphlet may be quoted in full. “Theories tire of little or no value until we can interpret them in terms of successful application in ordinary herds and under ordinary conditions in which cattle are kept; the specific germ theory of abortion up to this time has been a failure so far as practical results go, and it is up to us to direct our energies along different lines if we would get results. At this time the application of recent knowledge along the lines of nutrition seems to promise us the best results.”

Discussing the germ theory of abortion, Dr. Conn draws attention to certain facts. The germ which is said to cause abortion is very easily destroyed. Also it appears to have no ill-ciTeet upon cows infected by its presence. It has been established that the animal may he infected and yet not abort. The author then asks some unanswered questions, relative to the germ theory, viz.: —

Why do we have a greater proportion of abortions in young animals than in older ones’’

Why will a germ that is so mild in its action and which will not produce any symptoms of disturbance in the cow, bring about the death of the foetus?

A large proportion of abortions occur at from five and a-half to seven months, it does not appear reasonable that the germs would live in the uterus for many weeks waiting for just this stage in the development of the young to do their damage; it is evident that there is some other reason for its occurrence. As we see it, the state of nutrition plays a deciding hand here, as it is known that the foetus is then making its greatest growth.

The feeding then may fail to supply the elements vital to maintain the dam and the unborn calf as well. This is particularly so in the case of young animals that are still themselves in the growing - stage. ‘Noted authorities have been able to trace serious outbreaks of abortion to no other cause than that of a deficient ration.

Further information of particular interest is that plants will vary as to mineral content from year to year due to the season, as so great a difference as 37 per cent, in the lime content has been observed from year to year. It stands to reason that the variations wall have an effect on the animals consuming the feeds.

We have, too, to consider the artificial state to w hich dairy cows have been brought. In its native state a cow - produces less than 401bs. of butter-fat to rear her call:. "We now demand a production about six times as great. Do vc feed the eow proportionately? Certainly we do, so far as producing feeds go, but v’liat of the maintaining foods?