The pattern of digestive enzyme activity and growth of marine fish larvae mangrove red snapper Lutjanus argentimaculatus (Forsskål, 1775)

Abstract

Mangrove red snapper Lutjanus argentimaculatus is a highly valuable marine fishery and should be cultivated to ensure sustainability. The growth is crucial for larvae rearing, and the digestive enzyme influences the larval growth. This study aimed to determine the pattern of digestive enzyme activity and its relationship to larval growth. Digestive enzymes consisting of protease and amylase were quantified using a spectrophotometer, while lipase was tested using a titration method. Total length and body weight used to measure larval growth. Samples of larvae were collected at 5, 10, 15, 20, and 25 Days After Hatching (DAH). According to the results, digestive enzyme activity was detected at 5 DAH larvae, even though the levels were deficient. Further, the digestive enzyme activity increased and exponentially correlated (r = 0.96) to larval age. The total length and body weight indicated larvae growth, which performed polynomial (r = 1) and exponential (r = 0.99) correlation, respectively, to larval age. Based on this study's finding, the digestive enzyme activity of mangrove red snapper L. argentimaculatus larvae increased in line with the increasing larval age. In addition, there was also a very close correlation between digestive enzyme activity and larval growth.