STOCK FROM ABROAD

New Zealand Herald, Volume LXX, Issue 21617, 9 October 1933, Page 16

STOCK FROM ABROAD

TYPES IN ENGLAND f EVOLUTION IN DOMINION BY H.H.T. The cjuostion of lifting or retaining the embargo on livestock importations which is being discussed up and down the country lias raised the subject of the benefits, if any, that would accrue an a result of further importations from Great Britain. Those whose qualifications to make a comparison between our purebred livestock and that in the Homeland unquestionably assure us that our best New Zealand animals are varying considerably from the types which are looked upon as the best representatives of the various breeds in Great Britain. Unfortunately these statements have been of too general a nature for us to find out exactly where each particular breed differs. Had wo some definite statements regarding these differences it would be possiblo for us to work back to the cause in most instances and breeeding or treatment could be rectified where these wcro at fault, or, where it was found that environment had induced the variation, we could set about moulding the new tvpc into its most productive form. Misdirected Energy Tt would bo misdirection of energy to attempt to maintain a characteristic in any particular breed which did not fit for its enviroment here. Nature appears to mould all types of life toward that best suited to the environment in which it is placed. Man can only benefit himself by working with Nature to hasten the process of acclimatisation, and at the same time, through breeding and feeding, to develop to their fullest possible extent those features which will benefit himself. In lower forms of life adaptation to environment takes place much more rapidly than among what we term " higher " forms, and mi these again much more rapidly than in man himself. Thus we often find, to our surprise, that grasses which were brought out to New Zealand from the Old World a few years ago, have developed characteristics dilferent from, and sometimes considerably improved upon, their parent stock. In these instances, where we discover that a variation has already taken place, we do not think of applying immediately to the place where tho grass originated to procure " the correct _ type " again, but, realising that in spite of any efforts we may make the new type will persist in its new surroundings, we set about, by selection and propagation, to improve a typo which obviously is best adapted to its environment. Australian Experience In one area in South Australia where the climate is exceedingly hot and the atmosphere very dry, it was found that the Merino sheep introduced there, in a very short time invariably produced extremely fine and very closely-crimped or " serrated " wool. Thg fineness and serrations wercf a distinct advantage, but it was also found that the fleeces were getting much lighter than those of the stock from which the sheep originated. For .some years importations of heavily■woolled rams from outside districts were made to keep tho weight of tho clip up, but it was soon found that the fino-woolled, lighter-fleeced sheep persisted. Then some breeder who had pat considerable thought and observation into the problem conceived the idea of accepting tho fine wool and devoting his energies to increasing tho fleece weight by-breeding for "density," or a greatly increased number of fibres of fine wool per square inch of skin surface. In a short time the sheep of that district were producing an equally heavy fleece of much n»ore valuable wool than the parent stock from which they were derived. Climate and feed affect wool and hair perhaps more quickly than any other single feature. Tho Highland Blackface sheep, with long straight wool almost devoid of even a " wave " will, if transported to the hot climate of Australia, soon develop a " wave " like tho Lincoln. In tho course of a few generations this wa\ e would become a " crimp " or something closely resembling it. Why is this? And why can breeders not maintain these nnimals in their native form in a new enviroment? The answer is really very simple, and may possibly help us in New Zealand to realise one reason why we cannot hope to maintain unaltered English tvpo here. Influence of Climate One can understand that the actual thickness of tho skin of a man or beast will alter in climates of different temperature. Thus the Esquimau, or even the Scotchman, both of whom have lived for many generations in comparatively cold climates, have much thicker skins than say, the African ■Negro. In the thicker-skinned races the hair follicles or roots have sufficient thickness of skin in which to gtand upright, and they produce straight hair, the fibres being almost circular. In warmer climates, the skin becomes thinner to facilitate heat radiation, and the result is that the hair roots, or follicles, must bo at an angle to secure tho necessary depth of root, and are compressed to a certain extent. This compression flattens the hair, so that tho fibres become oval in section instead of round, and this "flattening" causes it to curl just as a wood shaving will naturally curl. Where hot, dry climate necessitates a thin skin for tho animal to quickly radiato body heat, tho wool will bo fine, inclined to be open, and with a tendency to increased crimpiness. Where the climato is colder the skin will become thicker, and the wool straighter and generally coarser. Tho feature of coarseness or fineness docs nqt always apply, because wool is naturally an undercoat designed to keep the animal •warm and had growing through it originally a number of coarse hairs which formed an outer protective coat. In cold climates there is a tendency for this heavy coat to return in tho guiso of " kemps." Many Other Factors There aro many influences besides the climato which determine the development of variations in livestock. Food, and tho quantity and proportions of tho various minerals which ib contains, has probably a still greater influence. With all these factors inducing variations in our livestock, it would seem to bo an almost impossiblo task to try and maintain our animals at English standards of typo. The goal on which wo should concentrate should be, 1 should think, to establish types of each of the breeds which have been imported that aro perfectly adapted to their new environment, and to concentrate on making these highly productive and profitable. There seems to be no bar to our making New Zealand types even more profitable than the stock from which they derived. . The evolution of our own. Dominion types of livestock does not necessitate further importations from abroad; indeed, such importations of an unacclimatised type would be a retrogressive step as it would bo working against the natural laws of evolution.