Phosphorus (P) and calcium (Ca) are essential minerals for adequate bone development in pigs and broilers. Bone minerals provide strength and mechanical rigidity to the bone whereas the organic matrix (mainly collagen) provides flexibility, elasticity and tensile strength. We conducted two dose-response studies, with dietary P content (constant Ca:P ratio) increasing from 50 to 130% of current recommendations in 5 equidistant steps in individually housed growing male and female pigs (25-125 kg BW) and from 75 to 137.5% of current recommendations in 6 equidistant steps in group-housed male Ross 308 broilers (0-39 d of age). Bone characteristics, i.e. dimensions, weight, mineral content in fat-free-dry matter, and breaking strength (with Instron 5,564 materials tester), were determined in metacarpus 3 and 4 of pigs at 50, 80 and 125 kg BW and in tibia of broilers of 10, 21, 30, and 39 d of age. In pigs, metacarpus ash content increased linearly (P<0.001) and quadratically (P<0.05), while total ash mass, bone breaking strength and stiffness increased linearly (P<0.001) with increasing dietary P content. At the same dietary P supply, metacarpus breaking strength and stiffness were substantially higher (P<0.01) in female pigs than in entire male pigs. This effect was partly related to a higher bone ash content in the female pigs. In broilers, tibia ash content and total ash mass increased linearly (P<0.001) with increasing dietary P content, whereas an increasingly significant linear effect of dietary P content on tibia breaking strength was observed with increasing age of the birds. This may suggest that in young birds breaking strength was less suited to determine bone development. In general, dietary P content required for maximum growth performance was below P intake for maximum bone strength. Hence, minimum or optimum bone characteristics need to be defined. The relevance and value of different characteristics and similarities between pigs and birds will be discussed.
|Titel||Book of Abstracts of the 68th Annual Meeting of the European Association for Animal Production|
|Status||Gepubliceerd - 28-aug-2017|
|Evenement||68th Annual Meeting of the European Federation for Animal Science - Tallinn, Tallinn, Estland|
Duur: 27-aug-2017 → 1-sep-2017