INTERACTION BETWEEN DIETARY MINERAL AND PHYTASE ON BIOLOGICAL PERFORMANCES OF JAPANESE FLOUNDER, Paralichthys olivaceus. PART II. MINERAL DIGESTIBILITY AND VERTEBRAL MINERAL CONTENT
Abstract: Interactive effects
between dietary inorganic phosphorus (IP) and phytase (P) on mineral
digestibility and vertebral mineral content were investigated in a 30 days
feeding trial followed by three weeks digestibility trial with Japanese
flounder, Paralichthys olivaceus. Eight experimental diets were formulated
based on two levels of dietary Ca at 0% and 0.2% combined with either 0% or
0.25% of dietary IP and either with 0 and 2,000 fytase unit (FTU)/kg of phytase
in diet, respectively. Result indicated that digestibility of total phosphorus
significantly increased by three dietary compounds where the highest was
observed in fish fed diet contained 0.25% IP and 2,000 FTU phytase/kg and
dietary Ca also included in diet. Significant interaction was only detected
between dietary IP and P on this parameter. Supplementation of IP and Ca not
phytase significantly improved Ca digestibility. Ca digestibility was very poor
when dietary IP and Ca were not supplemented in diet even with when phytase
supplemented in diet. There was significant interaction between dietary IP and
Ca on Ca digestibility. Vertebral total phosphorus, Ca, and Mg content as well
as Ca:P ratio were significantly enhanced by dietary IP and phytase. Dietary Ca
has significant effect only on vertebral total phosphorus. Interaction between
dietary IP and Ca was significantly found on vertebral Ca content and Ca:P
ratio. No significant second-order interaction was observed among the three
dietary mineral on overall parameters. Based on total phosphorus and Ca
digestibility as well vertebral phosphorus content found in this study, dietary
IP, Ca, and phytase at rate of 0.25%, 0.2%, and 2,000 FTU phytase/kg diet,
respectively are needed to supplement in diet for a better mineral absorption
and bone mineralization.
Keywords: mineral; phytase;
digestibility; vertebrae; Japanese flounder
Author: Asda Laining, Lideman
Lideman, Shunsuke Koshio
Journal Code: jpperikanangg150042
