Zoological Studies

Vol. 40 No. 4, 2001

Effects of Light Regime, Algae in the Water, and Dietary Astaxanthin on Pigmentation, Growth, and Survival of Black Tiger Prawn Penaeus monodon Post-larvae

Chih-Hung Pan1, Yew-Hu Chien1,* and Jin-Hua Cheng2

1Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan 202
2Tungkang Marine Laboratory, Taiwan Fisheries Research Institute, Tungkang, Pingtung, Taiwan 928

Chih-Hung Pan, Yew-Hu Chien and Jin-Hua Cheng (2001) The astaxanthin content of penaeids can be increased through ingestion of food containing different carotenoids. Illumination and background probably affect pigmentation as well. There are some indications that astaxanthin also plays biological roles other than in pigmentation, such as improve- ment of growth and survival. The aim of this study was to find out the effects of light regime, algal in the water, and dietary astaxanthin on body astaxanthin, and subsequent growth and survival of tiger prawn Penaeus monodon post-larvae. An experiment with 2 x 2 x 2 factorial arrangement of treatments was conducted, which included 2 diets without or with astaxanthin supplementation (80 mg astaxanthin/kg) fed on tiger prawn post- larvae in water without or with the addition of microalgae (Isochrysis galbana, 3.63-8.70 g/L) under a 24-h dark or light environment for 4 wk. Body astaxanthin concentrations decreased significantly as prawns grew. Light had significant effects in preventing body astaxanthin reduction only during the 4th wk, but both algae in the water and dietary astaxanthin had significant effects in preventing body astaxanthin reduction from the 1st wk.  There were no significant effects of light regime, algae in the water, or dietary astaxanthin on prawn growth. Throughout the experiment, the survival of prawn reared in the light was significantly higher than that for prawn reared in the dark. The survival of prawn reared in algae-containing water was significantly higher than that of prawn reared in clear water except in the 3rd wk. Dietary astaxanthin improved prawn survival only in the 1st wk. Only in the 4th wk did survival have a positive correlation with prawn body astaxanthin concentration.  The results suggest that  it is essential to maintain a certain level of astaxanthin in tiger prawn post-larvae for better survival while the prawn are growing and their astaxanthin is decreasing.

Key words: Carotenoids, Crustacean, Pigment conversion, Biological function.

*Correspondence: Tel: 886-2-24622192 ext. 5204. Fax: 886-2-24625393. E-mail: yhchien@mail.ntou.edu.tw