The economics of feeding horses / [Harold A. Woodruff].

  • Woodruff, Harold A.
Date:
1912
Catalogue details

Licence: In copyright

Credit: The economics of feeding horses / [Harold A. Woodruff]. Source: Wellcome Collection.

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    and prevents the digestion to a greater or lesser extent of other soluble constituents, the digestibility of a food- stuff by the horse may be said to vary inversely as the amount of crude fibre present. Most of the herbivorous domesticated animals can digest a considerable part of the soft fibre of green plants, but only ruminants (ox, sheep, and goat) are able to extract any nourishment from the hard, woody fibre of foods like straw and the coarser leguminous plants. The nitrogenous constituents of a food occur in one of two forms, either as proteins or as amides. The proteins, albuminoids, or, as they are often called, flesh- formers, are essential constituents of a diet, because, besides being broken down in the body so as to give up heat or energy, they are the only constituents of food which can build up and repair the muscular tissue which has been subjected to the wear and tear of work. After digestion these bodies are assimilated—i.e., they are in- corporated into the proteid tissues of the body. When a working animal is neither gaining nor losing weight, protein is being assimilated to the same extent as the proteid tissues have been broken down by wear and tear, and this is the minimum amount of albuminoid matter that must be supplied in the food. When broken down in the body by combination with oxygen, proteid tissue is not oxidised to its simplest form, but splits into several bodies, the ultimate products of which are carbon dioxide, water, and urea. Urea is an incompletely, oxidised constituent of the urine eliminated from the blood by the liver and kidneys, and it contains practi- cally all the nitrogen taken in as food. The amount of urea excreted is therefore an index to the amount of proteid decomposition which has taken place in the body.