Circadian regulation of calcium and phosphorus homeostasis during the oviposition cycle in laying hens

• DOI: 10.1016/j.psj.2023.103209
• Publication Date: 2023-11-11T04:34:29Z
• Authors: Micaela Sinclair-...; R. Alejandra Garc...; Lyssa R. Blair; Roselina Angel; Xabier Arbe; David Cavero; Laura E. Ellestad
• Keywords: Laying; Homeostasis

Maintenance of calcium and phosphorus homeostasis in laying hens is crucial for preservation skeletal integrity eggshell quality, though physiological regulation these systems incompletely defined. To investigate changes mineral vitamin D3 during the 24-hour egg formation cycle, 32-week-old commercial were sampled at 1, 3, 4, 6, 7, 8, 12, 15, 18, 21, 23, 24 hours post-oviposition (HPOP; n≥4). Ovum location calcification stage recorded, blood chemistry, plasma metabolites, circulating parathyroid hormone (PTH), expression genes mediating uptake utilization evaluated. Elevated levels renal 25-hydroxylase from 12–23 HPOP suggest this tissue might play a role 25-hydroxylation calcification. In shell gland, retinoid-x-receptor gamma upregulation between 6 to 8 followed by subsequently increased D receptor indicate that signaling important Increased PTH, calcitonin, fibroblast growth factor 23 (FGF23) receptors gland 18–24 elevated sensitivity hormones towards end Shell sodium-calcium exchanger 1 was upregulated 4 7 membrane ATPase throughout calcification, suggesting primary transporter may differ according stage. Expression further indicated bicarbonate synthesis precedes transport, where peaked 6–7 12–18 HPOP, respectively. Inorganic (PiT-1) kidney 12–15 likely excrete excess phosphorus, 18–21 HPOP. Upregulation FGF23 PiT-1 late time. Together, findings identified potentially novel hormonal pathways involved along with associated circadian patterns gene can be used devise strategies aimed improving strength hens.