Dietary Phosphorus Requirement of Juvenile Malabar Grouper (Epinephelus malabaricus)

馬拉巴石斑稚魚對磷需求量之探討

鄭安倉(Ann-Chang Cheng) ； 吳建達(Jian-Da Wu) ； 楊順德(Shuenn-Der Yang) ； 劉擎華(Chyng-Hwa Liou)

《臺灣水產學會刊》 32卷1期 (2005/03) Pp. 41-52

https://doi.org/10.29822/JFST.200503.0004

摘要

本試驗以磷酸一鈉為主要磷源，以0.12%磷含量的梯度逐量添加在酪蛋白與明膠的基礎飼料（粗蛋白45%、15.90MJ能量/kg diet）中，磷含量由0.26到1.10%共八組試驗飼料，探討馬拉巴石斑(Epinephelus malabaricus)稚魚對飼料磷的最適需求量。每一飼料組有三重複，每一重複8尾石斑稚魚（平均重約7.33g)，置於過濾循環水族箱中餵養14週，每日投餵量為魚體重的3%，分三次投餵。飼育試驗結果顯示，馬拉巴石斑之成長率及飼料效率均隨飼料磷含量的增加而增加，但在磷含量0.74%以後的各組則有下降的趨勢，而由試驗魚的成長率依折線迴歸模式求得最適磷需求量為0.74%。形態測定的結果表明，投餵飼料磷含量不足者其尾叉長／體高之比值顯著較低。各組魚隻的肝體比雖無顯著差異，但肝臟油脂含量則以飼料磷含量不足者明顯高於磷量充足的各組；血球容積比和血紅素濃度不因試驗飼料而有顯著差異，但血漿磷含量則顯著隨飼料磷含量的增加而增加。另外，餵以飼料磷含量不足者其全魚體、脊椎骨和鱗片之灰分、鈣和磷的比例顯著較低。本次試驗結果發現，馬拉巴石斑稚魚的飼料中缺乏磷會導致成長低下、食欲不振、體色黑化、活動力差、頭骨變型、椎節短縮與棘狀構造末端捲曲、骨骼礦化不良以及肝臟脂質含量增多等缺乏症。

關鍵字

馬拉巴石斑 ； 磷 ； 需求量 ； 缺乏症

並列摘要

A growth trial was conducted to estimate the phosphorus requirement of juvenile malabar grouper. Eight semipurified (casein-gelatin based) diets were formulated to contain 45% crude protein, 15.90 MJ energy/kg diet and supplemented phosphorus (monobasic sodium phosphate) levels ranging from 0.26% to 1.10%. Each diet was fed to triplicate groups of 8 fish with an initial average weight of 7.33 g over 14 weeks. The fish were fed by hand at 3.0% body weight three times daily. At the end of the trial, percent weight gain increased significantly (p＜0.05) with increasing dietary phosphorus from 0.26% to 0.74%, the values slightly decreased thereafter. Similar trend was observed for feed efficiency. Broken line regression analysis of the weight gain data indicated that phosphorus requirement of juvenile malabar grouper for maximal growth was satisfied with a diet containing 0.74% phosphorus. For morphological measurements, the ratio of fork length per body depth was lower in fish fed diets containing insufficient phosphorus levels. The hepatosomatic index was not affected by dietary treatments, but liver lipid contents were higher in fish received lower dietary phosphorus levels. The haematocrit value and hemoglobin concentration were not different among dietary treatments. Plasma inorganic phosphorus of fish received insufficient dietary phosphorus was noticeably lower than that of fish fed phosphorus sufficient diets. Ash, calcium and phosphorus contents of whole body, vertebrae or scales were depressed in the fish received low phosphorus diets. Signs of phosphorus deficiency were characterized by poor growth, loss of appetite, dark coloration, lower physical activities, deformed head, shorten vertebrae gap and crooked spine, poor bone mineralization and an increase in liver lipid content.

並列關鍵字

Malabar grouper ； Phosphorus requirement ； Deficiency symptoms