Growth Performance and Digestive Characteristics of Starry Flounder Platichthys stellatus on the Moist and Extruded Pellets

A study was carried out to observe the effects of feed types on the growth, feed preference, and enteric feed transition rate of juvenile starry flounder, Platichthys stellatus for 45 days. Fifty fish (avg. 135 g) were stocked each in replication, and fed a commercial extruded pellet diet (EP, 45% protein) and a moist pellet diet (MP, 65% raw mackerel+35% feed powder in wet basis), respectively. The MP presented the higher performance than that of the EP on the feed efficiency (<TEX>$68.3{\pm}0.9%$</TEX> for EP and <TEX>$92.3{\pm}4.3%$</TEX> for MP) and the specific growth rate (<TEX>$1.07{\pm}0.07$</TEX> for the EP and <TEX>$1.20{\pm}0.05%$</TEX> for the MP). In contrast, the EP showed the higher feed preference in terms of the daily feed intake (<TEX>$1.57{\pm}0.08%$</TEX> for the EP and <TEX>$1.30{\pm}0.01$</TEX> for the MP) and the ad libitum feeding rate after a fast of 72 hours (1.73% for the EP and 1.35% for the MP). The feed transition rate through intestinal canals decreased exponentially in both the EP and the MP, showing the faster transition rate with the EP. In the result, starry flounder appeared to have the better feed preference to the EP, but have the higher feed efficiency and growth performance to the MP.