Ontogeny of alpha - amylase activity during early development of the common bream (Abramis brama)

This study was conducted to investigate the growth pattern and ontogeny of the activity of alpha amylase enzyme in common bream (Abramis brama) from hatching through 60th day post hatching (dph) at the Shahid Ansari breeding and restocking center (Rasht, Guilan, Iran). The results showed that wet weight and total length of common bream were 0.65 ± 0.03 mg and 4.66 ± 0.24 mm at hatching, respectively. The growth pattern from early development through 60th dph was exponential as Y = 5.9558e0.0346xand R² = 0.97. The results also revealed that alpha- amylase enzyme was present at the hatching and its activity was constant till 4th dph and had an increasing trend till 25th dph. Then, a significant decrease was observed in the activity of this enzyme on 35th dph; thereafter its activity showed an increasing trend till 60th dph. In addition, the activity of alpha-amylase showed a strong relationship with increasing the age of specimens. The results also revealed that ontogeny of the alpha-amylase in common bream larvae are similar to that of other omnivorous and herbivorous fishes. It can be concluded that the food with higher content of carbohydrate can be used after 12th dph for feeding of their larvae.