H.—34

Intensive Investigations.—Further data have been collected from the experiment with stud Romney and Corriedale sheep under accurately known nutritional environment. The following table of fleece weights records some of the more striking results : —

The wool of the Corriedalc low-plane sheep, although fine, is very good to excellent in character; the Romney wool, on the other hand, is definitely lacking in character. The highest fleece weights obtained were 22 lb. greasy wool for twelve months' growth from a Corriedale ewe and 21 lb. for a Romney ewe. Both ewes reared lambs. Hogget fleeces have been obtained from the progeny of the original high- and low-plane ewes shorn at fourteen months, the results being as follows :—

The highest fleece weights recorded were : Romneys, 23-0 lb.; Corriedales, 21-8 lb. Both the ewes and their offspring have been followed, at six-monthly intervals, with measurements of fat and suint content; fat and suint production per unit area ; fibre length, diameter, density, and wool-production per unit area. The largest difference in clean-wool production between the high- and low-plane sheep amounted to 420 per cent. This was during the first six months of the experiment. In an attempt to extend these more detailed studies of environmental effects on wool growth, someeight hundred samples from the Department of Agriculture's Kirwee experimental area have been graded and scoured. A total of 482 samples from copper- and cobalt-deficient areas have been examined. Investigations so far carried out have given no support for the suggestion advanced last year that acidosis and/or ketosis, associated with pregnancy toxemia, were directly responsible for interference with wool growth and the production of breaks in the staple. Wool Metrology.—A large number of fineness measurements have been made in connection with wool survey and other projects. A few samples have been examined on behalf of stud breeders. The arrival of standard equipment for projection of fibres at a magnification of 500 diameters has speeded up this work. Important anomalies are being found between measured fineness and count estimated by experts from the appearance of the sample in the grease. A small number of samples have been scoured on behalf of wool-broking firms to determine yield of clean wool. Manufacturing Trial.—Last year's attempt to procure raw material for a trial to determine the effect of medullation on the processing of 56's-60's wool failed to provide sufficient medullated wool, despite the examination of over one thousand fleeces. A further one thousand fleeces in about twenty lines were examined this season, and about 200 lb. of wool containing a small amount of medulla have been obtained. Most of this wool came from two lines of wool grown by hoggets not shorn as lambs. It has become apparent that a great deal of wool which is substantially free from medulla is described by the trade as " hairy " because of damage by weathering influences which render the fibres harsh and brittle as well as interfering with their behaviour in the dye bath. MASSEY AGRICULTURAL COLLEGE Sheep Nutrition Experiments E. A. Clarke The contention has been advanced in many quarters that a largo number of our stock troubles could be attributed to a simplicity rather than a complexity of diet and that perennial - rye-grass - dominant pastures tended to promote ill-thrift in stock'. Also, it was contended that sheep in particular did not thrive on lush rye-grass - white-clover pastures, especially those pastures resulting from the heavy top-dressing of the newer strains of rye-grass and white clover. In view of these beliefs it was decided to carry_ out tests on productivity, thrift, and finish of breeding-ewes and lambs of— (a) The following manurial treatments of a basic rye-grass - white-clover pasture— (i) 1 cwt. superphosphate per acre : (ii) 4 cwt. superphosphate per acre : (iii) 4 cwt. basic slag per acre : (iv) 4 cwt. superphosphate plus lime per acre : (v) 4 cwt. superphosphate plus lime plus potash per acre. (b) The following pasture mixtures heavily top-dressed with lime and superphosphate— (i) Pedigree perennial rve-grass plus pedigree white clover (high H.C.N.) : (ii) Pedigree perennial rye-grass plus low H.C.N. white clover : (iii) Pedigree -perennial rye-grass plus mother seed white clover : (iv) Mother seed perennial rye-grass plus mother seed white elover : (v) Mother seed perennial rye-grass plus pedigree white clover.

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Treatment Group. Bomney. Corriedale. Treatment. High .. .. .. 12-8 14-8 6 months' normal- and 6 months' AigA-plane feeding. Low •• •• •• 7-8 6 months' normal- and 6 months' /ow-plane feeding. High .. .. .. 15*6 18*0 12 months'high-plane feeding. Low •• •• •• 5 '2 5-8 0 months' low-plane feeding and 0 months' maintenance. High .. .. .. 12-0 10-6 6 months'high-plane feeding and 6 months'maintenance. Low .. .. .. G'6 8'4 12 months' maintenance.

| Tfcomneys, J Oorriedales. J —— High .. .. 19-7 in-3 Optimum conditions. Low .. .. 7 • 0 9-1 Corresponding to average hill country.