Effects of Ascophyllum and Spirulina Meal as Feed Additives on Growth Performance and Feed Utilization of Red Sea Bream, Pagrus major

養魚飼料への藻類添加は生理状態の向上に有効であることが明らかにされているので、本研究ではマダイについて Ascophyllum と Spirulina の効果をみた。対照区には配含飼料に5%のセルロース、Ascophyllum 区、Spirulina 区にはそれぞれ藻類の粉末を5%添加した。初期体重85gのマダイ1年魚を77日間飼育し、成長、飼料利用率、生物学的性状、体成分に及ぼす効果をみた。いずれの藻類の添加においても成長、飼料効率、タンパク質効率、筋肉タンパク質蓄積量が向上し、筋肉成分では脂質蓄積量に増加がみられた。Spirulina の投与では悪影響は認められず、各項目においてAscophyllum より優れた効果を示し、これまでに報告された藻類に匹敵するか、もしくはそれ以上の効果を示した。

Following up on findings that algae as feed additives improve the physiological condition of cultured fish, the efficacy of Aseophyllum and Spirulina as feed additives was investigated in one year old red sea bream, Pagrus major (ca. 85 g in body weight). Control feed was supplemented with 5% cellulose. In experimental feeds, cellulose was replaced by 5% algae meal. These feeds were provided for 77 days and the effects on growth, feed utilization, and body composition were monitored. Feeding on both Ascophyllum and Spirulina elevated growth rates and improved feed conversion efficiency, protein efficiency ratio, and muscle protein deposition without negative effects. Spirulina showed the most pronounced effects on growth and feed utilization, compared to those macroalgae which have been tried so far.