Determination of pre-cecal phosphorus digestibility of inorganic phosphates and bone meal products in broilers.
A broiler study was performed to determine the pre-cecal phosphorus (P) digestibility of 5 P sources, 3 from animal (Delfos, Calfos, and porcine bone meal) and 2 of inorganic (monocalcium phosphate [MCP] and dicalcium phosphate [DCP]) origin. Delfos is processed from bones resulting in a dicalcium phosphate product, and Calfos is processed from bones in which part of the gelatin is removed but in which the hydroxy-apatite matrix is preserved. During the first 14 d, birds were housed in floor pens bedded with wood shavings and received a commercial starter diet. At d 14, broilers were randomly assigned to pens (0.9 m2, 10 birds/pen) with a slatted floor. From d 14 onwards, one of the 6 experimental diets (a basal diet, and 5 diets containing the P sources) was provided. Test diets were replicated 6 times, and the basal diet 8 times. Electron microscopy images of test products were made in order to verify whether the spatial structure of the test products could be related to the pre-cecal P digestibility of the same products. Diets met or exceeded CVB (2011) requirements for all nutrients except for P and were formulated to contain a calcium to total P ratio of between 1.4 and 1.6 and a minimal amount of phytate P. Diets contained 5 g/kg titanium oxide as a marker to determine digestibility of P. At d 24 all birds were euthanized, after which the content of the terminal part of the ileum was sampled. The P digestibility was calculated by linear regression according to World's Poultry Science Association (WPSA) protocol for determination of pre-cecal P digestibility. Pre-cecal P digestibility of MCP, DCP, Delfos, Calfos, and porcine bone meal was 88.5, 82.4, 94.5, 86.9, and 78.2%, respectively. Based on visual inspection of electron microscopy images of test products, the spatial structure of the test products might be related to P digestibility. It is concluded that processing of bone meal increases the pre-cecal P digestibility in broilers.
Wageningen Livestock Research, PO Box 338, 6700 AH Wageningen, the Netherlands.
J
J
van Harn
Wageningen Livestock Research, PO Box 338, 6700 AH Wageningen, the Netherlands.
J W
JW
Spek
Darling Ingredients International, Kanaaldijk Noord 20-21, 5691 NM, Son en Breugel, the Netherlands.
C A
CA
van Vuure
Wageningen Livestock Research, PO Box 338, 6700 AH Wageningen, the Netherlands.
M M
MM
van Krimpen
D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001688:Biological Products / Q000008:administration & dosage / Q000378:metabolism; D002136:Calcium, Dietary; D002645:Chickens / Q000502:physiology*; D004032:Diet / Q000662:veterinary*; D019587:Dietary Supplements; D004063:Digestion / Q000502:physiology*; D008297:Male; D008903:Minerals / Q000008:administration & dosage / Q000378:metabolism*; D010710:Phosphates / Q000008:administration & dosage / Q000378:metabolism*; D016226:Phosphorus, Dietary / Q000008:administration & dosage* / Q000378:metabolism
D001688:Biological Products; D002136:Calcium, Dietary; D008903:Minerals; D010710:Phosphates; D016226:Phosphorus, Dietary; C027762:bone meal
bone meal; broilers; digestibility; phosphorus