Phosphorus Nutrition of Ruminants
نویسنده
چکیده
Most Australian soils are derived from parent material which is low in phosphorus. Soils of low phosphorus status support early maturing, grass dominant pastures with a short summer growth period and hence lengthy period of senescence. Phosphorus in these grasses may be as low as 0.02 g P/100 g OM during senescence (Robinson and Sageman 1967) and may only reach 0.15 g.P/lOO g OM during active growth. These are the pastures which are grazed by many of Australia's livestock.
منابع مشابه
II. Quantitative aspects of phosphorus absorption in ruminants.
Phosphorus absorption in ruminants was analysed from a database described in a previous article. For common values of ingested phosphorus (2.5-5.0 g x kg(-1) of DM), 0.73 of dietary phosphorus is absorbed. The remaining variability is probably due to phosphorus quality. Phosphorus absorbed from silage, cereal, cereal by-products and hay differs greatly. The current true absorption coefficient u...
متن کاملIII. Quantitative aspects of phosphorus excretion in ruminants.
Ruminant phosphorus excretion and metabolism were studied through a database. Faecal endogenous phosphorus is the main pathway of phosphorus excretion and averages 0.85 of total faecal phosphorus. The remaining 0.15 is unabsorbed dietary phosphorus. Faecal endogenous phosphorus is mainly unabsorbed phosphorus, with saliva being the major source, and is correlated to factors influencing saliva s...
متن کاملUtilisation of phytate phosphorus by rumen bacteria in a semi-continuous culture system (Rusitec) in lactating goats fed on different forage to concentrate ratios.
Experimental data on phytate phosphorus utilisation by ruminants are scarce. The aim of this study was to estimate the phytase activity of rumen micro-organisms when phytate phosphorus supply is high. A semi-continuous culture system fermentor (RUSITEC) was used. The inoculum was obtained from eight goats fed on either high or low forage level diets. Experimental buffers only differed by the na...
متن کاملEndogenous phosphorus loss in ruminants: A review
Phosphorus (P), a major mineral in animal nutrition is currently a focus of the livestock industry. This is because of its high fecal excretion by livestock and the subsequent environmental pollution, especially in the eutrophication of lakes and surface water. Areas of intensive animal husbandry and dairy farms where P is fed in excess are particularly affected. Ruminants must be fed according...
متن کاملIn vitro Evaluation of the Nutritive Value of Trianthema portulacastrum as a Source of Fodder for Ruminants.
Trianthema portulacastrum (common farm weed in tropical countries) contains 21.5 ± 1.2% crude protein, similar to Lucerne with relatively low structural carbohydrate (neutral detergent fibre: 43.6 ± 3.1%). The mineral profile of T. portulacastrum was well above the critical level as far as calcium (0.3%), magnesium (0.2%), iron (50 ppm), copper (8 ppm), zinc (30.0 ppm) and manganese (50 ppm), w...
متن کامل