title: Studies in ruminant nutrition with particular reference to the use of a concentrated liquid protein, mineral and vitamin solution
Creators: name: Bass, Jean Margaret
Publisher: name: University of Glasgow
Year: 1980
Subjects: subject: Animal sciences.

description: The work in this thesis investigates the use of a novel concentrated feed supplement (LS) which contains urea, calcium, 'phosphorus, sodium, trace elements and vitamins in a fully soluble liquid form vri.th principally 1100 g crude protein, 30 g Ca and 15 g P/kg. Such a concentrated liquid supplement night have advantages over a solid in that it could have a wide range of possible means of application to feeds for both large and small farm units. Considerable reliance is presently placed on providing supplementary nutrients in the form of free-access blocks or liquids in an effort to save labour on farms. Experimental studies are discussed that show that for these materials intake by ruminants in groups is far from uniform, many consume none of the materials offered. Methods of incorporating the liquid supplement into ruminant diets are examined in relation to the voluntary intake of oat straw, digestibility and animal performance and their subsequent use in production trials are investigated. In Section 1, LS supplementation was assessed in conjunction with alkali treatment of straw. Recent work has indicated that the addition- of alkali to straw increases its digestibility. However, when alkali treatment is used to improve the energy value of straw to allow a greater consumption there should in turn be a reduced requirement for cereals. This results in a reduced protein and mineral content in the diet and therefore the need for additional protein, mineral and vitamin supplementation. It was shown that LS supplementation ox straw (at chopping) was both practical and nutritionally advantageous and when the straw was simultaneously treated with NaCH the effect was additive, in terms of improved intake rather than improved digestibility. However, because on-farm treatment of straw with NaCH using existing machinery and equipment currently available is relatively expensive and presents some safety hazards to the operator, Ca(OH)2 treatments were investigated as an alternative. Ca(CH)2 treatment had no effect on straw digestibility, probably as a consequence of its relatively low solubility. Subsequently the ensiling of Ca(CH)2 treated straw was examined. The results were not promising and the treated materials were completely unsuited for animal feeding. In Section 2 various methods of presenting LS to ruminants were studied in relation to the voluntary intake and digestibility of straw-based diets (these included : LS in the drinking water; in a barley cube; in a molasses lick and sprayed on to oat straw). All methods of supplementation except LS via the water were found to be satisfactory in increasing intake or improving the digestibility of oat straw. In terms of animal acceptance, response and practical application the most practicable method of giving LS to ruminants was on the straw. In Section 3 the effect of LS supplementation on given production parameters was examined. LS supplementation of whole oats given to lactating ewes (suckling twin lambs) produced equivalent growth rates of lambs to that recorded when soya bean meal was the supplementary nitrogen source. The rate of use of LS was governed by the amount of supplementary nitrogen required in a given particular circumstance. Therefore the diet plus the LS addition may not provide the full amounts of calcium and phosphorus to meet current A.R.C. (1965) recommendations. The adequacy of LS was examined when given to ruminants receiving less Ca and/or P than the recommended intakes. It was found that LS was a convenient and adequate method of supplementation, when given on bruised barley and sugar beet pulp and that in general, although mineral intakes were lower than the current A.R.C. (1965) recommendations no deleterious affects were noted in the given production parameters that were investigated over extended periods with both pregnant and lactating and growing ruminants. It is concluded that the use of this fully soluble liquid containing urea, minerals and vitamins is a convenient and adequate method of supplementing ruminant diets and has wide range of uses with regard to both nutrient content and method of incorporation.