Loading...
Publication
Calcium handling in Sparus auratus: effects of water and dietary calcium levels on mineral composition, cortisol and PTHrP levels
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 90.9 KB | Adobe PDF |
Advisor(s)
Abstract(s)
Juvenile gilthead sea bream (Sparus auratus L.; 10–40·g body mass) were acclimatized in the laboratory to full strength (34‰) or dilute (2.5‰) seawater and fed normal,
calcium-sufficient or calcium-deficient diet for nine weeks.
Mean growth rate, whole-body calcium and phosphorus content and accumulation rates were determined, as well as plasma levels of ionic and total calcium, cortisol
and parathyroid hormone related protein (PTHrP; a hypercalcemic hormone in fish). When confronted with limited calcium access (low salinity and calcium-deficient diet), sea bream show growth arrest. Both plasma cortisol and PTHrP increase when calcium is limited in water or diet, and a positive relationship was found between plasma PTHrP and plasma ionic calcium (R2=0.29, N=18, P<0.05).
Furthermore, a strong correlation was found between net calcium and phosphorus accumulation (R2=0.92, N=16, P<0.01) and between body mass and whole-body calcium
(R2=0.84, N=25, P<0.01) and phosphorus (R2=0.88, N=24, P<0.01) content. Phosphorus accumulation is strongly calcium dependent, as phosphorus accumulation decreases in parallel to calcium accumulation when the diet is calcium deficient but phosphorus sufficient. We conclude that PTHrP and cortisol are involved in the regulation of
the hydromineral balance of these fish, with growthrelated calcium accumulation as an important target.
Description
Keywords
Hypocalcemia Growth Calcium balance PTHrP Cortisol
Citation
Abbink, W.; Bevelander, G. S.; Rotllant, J.; Canario, A. V. M.; Flik, G.Calcium handling in Sparus auratus: effects of water and dietary calcium levels on mineral composition, cortisol and PTHrP levels, Journal of Experimental Biology, 207, 23, 4077-4084, 2004.
