title: Determination of phosphorus fractions in animal protein ingredients.
abstract: Phosphorus (P) is present in different chemical compounds in animal feeds, and the solubility and digestibility of these different compounds are known to differ significantly. Animal protein ingredients generally have a high P content and are major contributors to total P of feeds for fish and other domestic animals. Estimation of different P compounds in these ingredients could help to improve the accuracy of estimates of digestible P contents of feeds. Bone P and organic P contents were quantified in 32 animal protein ingredients, including 10 fish meals, 14 meat and bone meals, and 8 poultry byproducts meals, using a fractionation protocol. The total P contents of the ingredients ranged from 2.1 to 8.3% on a dry matter (DM) basis. Organic P contents varied between 0.3 and 1.3% of DM. Highly significant (p < 0.001) linear relationships were observed between total P and ash and between bone P and ash for all ingredients combined: total P (%) = 0.185 x ash (%) (R (2) = 0.88), and bone P (%) = 0.188 x ash (%) - 0.852 (R (2) = 0.94). These results suggest that bone P can be easily and reliably estimated on the basis of ash content in animal protein ingredients.
authors.affiliation: Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G2W1, Canada.
authors.forename: Katheline
authors.initials: K
authors.lastname: Hua
authors.forename: Lijuan
authors.initials: L
authors.lastname: Liu
authors.forename: Dominique P
authors.initials: DP
authors.lastname: Bureau
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D004044:Dietary Proteins / Q000032:analysis*; D005396:Fish Products / Q000032:analysis; D008460:Meat / Q000032:analysis; D010758:Phosphorus / Q000032:analysis*
chemical_list: D004044:Dietary Proteins; D010758:Phosphorus