Animal nutrition / [Thomas Barlow Wood].

  • Thomas Barlow Wood
Date:
1924
Catalogue details

Licence: In copyright

Credit: Animal nutrition / [Thomas Barlow Wood]. Source: Wellcome Collection.

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    ratio of barley is 1:10 4, that of fish meal 1: -193. The required ratio is 1 : 7. Barley nutritive ratio 1:10'4 : 5 parts barley 5 : 52'0 Fish meal nutritive ratio 1: T93 : 2 parts fish meal 2 : '386 7 parts mixture 7 : 52'386 Nutritive ratio of mixture 1: 7'3 This calculation is entirely wrong, and the error is so large as to be serious. The correct ratio of the above mixture is found thus:— 100 lb. barley contain 65 lb. digestible protein, 1'2 lb. digestible fat, 62'2 lb. digestible carbohydrates, and 25 lb. digestible fibre. 500 lb. will, therefore, contain 325 lb. of digestible protein, 6 0 lb. digestible fat, 3110 lb. digestible carbohydrates, and 12-5 lb. digestible fibre. 100 lb. of fish meal contain 50 lb. of digestible protein, 42 lb. of digestible fat, no carbohydrate, and no fibre. 200 lb. will, therefore, contain 100 lb. of digestible protein and 8‘4 lb. digestible fat. Thus :— Digestible Protein, Fat, Carbohydrate, Fibre. 500 lb. barley ... 32'5 6-0 3110 12'5 200 lb. fish meal... lOO'O 8'4 — — 700 lb. mixture ... 132 5 14-4 3110 12-5 The correct ratio is therefore 14-4 x 2-3 + 3110 + 1 2-5 _ . 356 6 _ m^-27 1325 The ratio calculated by the so-called short method is, therefore, nearly three times wider than the correct ratio, and anyone feeding a mixtui-e computed by this method would be giving his animals nearly three times the correct proportion of protein.
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