EFFECT OF FOOD TYPES AND HABITATS ON THE VALUE OF FEMALE MATURITY INDEX (FMI) AND GONADO SOMATIC INDEX (GSI) IN THE EGG PRODUCTION OF MANGROVE CRABS, Scylla serrata

Abstract

<p>Mangrove crabs (Scylla serrata) is one of fishery commodities with high economic value for its good taste and nutrients content. Currently, increasing demand for this Crustacean species caused declining its population and for this reason, cultures of brooding crabs have been attempted. This study was carried out to investigate the egg development of mangrove crabs, with the main focus to study the effects of food types and habitats on the value of female maturity index (FMI) and gonado-somatic index (GSI). To investigate the effects of habitats, experiments were carrried out in the two habitats namely tidal flow of pond area and mangrove area. The spawning crabs were reared in a bamboo cage with the size of 2x1,5x1m3 divided into three paralel partition for 9-12 crabs with body weight of 200-250 grams. The crabs in the three partition were fed with three different foods, namely fish for the first partition, squid for the second, and mussel for the third. The results showed that no significant effect of foods and habitats was observed on the value of FMI. However, squid and mangrove habitats affected the growth, such as: an increase the wide of fifth abdomen segment, the widest abdomen segment and body weight during egg development periods. On the other hand, no significant different value of GSI was found on different habitats, but the food types affected the value of GSI.</p><p><br /><strong>Keywords</strong> : mangrove crabs, FMI, GSI, egg production</p>