Omara, Islam I.Mou, C. T.Persia, Michael E.Wong, Eric A.2021-09-272021-09-272020-04-010032-5791S0032-5791(20)30008-0 (PII)http://hdl.handle.net/10919/105081This experiment was conducted to examine the effect of 2 phosphorus (P) sources on broiler performance to day 14. The P bioavailability was estimated using bird performance and tibia ash measurements, whereas P digestibility, intestinal P transporter, kidney vitamin D-1α-hydroxylase, and vitamin D-24-hydroxylase mRNA abundances were also determined. Slope regression analysis was used to determine the bioavailability of dicalcium phosphate (Dical P) and nanocalcium phosphate (Nano P) with dietary available P (AvP) set to 0.20% P (control) using AvP from the major ingredients and Dical P. The experimental treatments were achieved by supplementation with either Dical P or Nano P to generate 0.24, 0.28, 0.32, and 0.36% AvP. A total of 648-day-old unsexed broiler chicks were divided into 72 birds per treatment (8 replicate cages of 9 birds). Slope regression analysis showed positive linear relationships between BW, feed intake (FI), tibia ash weight (TAW), and tibia ash percentage (TAP) with dietary Dical P and Nano P levels. Comparisons between regression slopes for Dical P and Nano P fed birds were not significantly different for BW, feed intake, tibia ash weight, and tibia ash percentage, indicating similar P bioavailability from Dical P and Nano P. There were interactions between P source and AvP for feed efficiency (FE) and apparent ileal P digestibility (AIPD). Dicalcium phosphate had greater FE than Nano P at 0.28% AvP and greater AIPD than Nano P at 0.24% AvP. The addition of AvP from Dical P and Nano P resulted in reduced sodium phosphate cotransporter mRNA abundance in the duodenum in a dose–dependent response. In the kidney, vitamin D-1α-hydroxylase mRNA abundance was greater at 0.36% Nano P compared with control, but there was no difference with Dical P. There was no difference in vitamin D-24-hydroxylase mRNA abundance between control and supplementation with Nano P or Dical P. In conclusion, Nano P and Dical P had the same bioavailability but had different effects on gene expression.Pages 1822-183110 page(s)application/pdfenCreative Commons Attribution-NonCommercial-NoDerivatives 4.0 InternationalLife Sciences & BiomedicineAgriculture, Dairy & Animal ScienceAgriculturedicalcium phosphatenanophosphatephosphate transportervitamin D hydroxylaseDIETARY NONPHYTATE PHOSPHORUSP-I DIETGROWTH-PERFORMANCEMINERAL PHOSPHORUSSMALL-INTESTINED-RECEPTORPHYTASEDIGESTIBILITYTRANSPORTERSUPPLEMENTSDairy & Animal Science0605 Microbiology0702 Animal Production0908 Food SciencesDuodenumKidneyAnimalsChickensCalcium PhosphatesPhosphorus, DietarySteroid HydroxylasesAvian ProteinsRNA, MessengerDietRandom AllocationBiological AvailabilityDose-Response Relationship, DrugAnimal FeedDietary SupplementsSodium-Phosphate Cotransporter Proteins, Type IIbNanoparticlesVitamin D3 24-HydroxylaseArticle - Refereed2021-09-27https://doi.org/10.1016/j.psj.2019.12.035994Wong, Eric [0000-0002-1891-5466]322414621525-3171