OVER-STOCKING

Ashburton Guardian, Volume 55, Issue 295, 26 September 1935, Page 10

OVER-STOCKING

CONFLICT OF OPINION. INCREASE IN DISEASE. All experienced men are acquainted with the broad results of environmental differences. We know, lor example, that overstocking is rathe.)' more than a contributory factor in. many diseases, but wo do not all know how it acts in some instances. Overstocking may be nutritional or it may be the mere concentration, of a given herd of stock on too small an area—depending upon the fertility of the soil, its mineral content, the composition of the pasture, the lain fall, and many other environmental factors. One may have overstocking on free range as well as in paddocks, and it may exist by the side of abundant herbage. Over-stocking might be defined as the management of pasturage so that the natural requirements of the animals, either in regard to nutrition or to cleanliness, are insufficiently met. Nutritional overstocking often results from the bad management of the available pasture, which, if divided into paddocks and given time sectionally for recuperation, would suffice. On farms where rabbits are not kept down one may observe in the diseased and badly nourished condition of these animals the effects of overstocking. Conflicting opinions as to the reasons for the increase in. disease illustrate the chaotic state of what is to-day regarded as authoritative opinion in academic veterinary circles (states a Homo writer). The view most firmly held by laboratory school of veterinary investigators is that the spread of disease has been almost entirely due to the establishment of a vicious circle whereby, for example, calves, are no. longer reared by dairy farmers to maintain the herd, which is thus necessarily replenished by infected stock brought in from tainted sources. On account of the diseases thus introduced (tuberculosis, Johne’s disease, mammitic, abortion), the wastage in the dairy herd increases, so that more and still more cows have to be bought and brought into the herd, again increasing the sources of' infection,. and so on.