Evaluation of Formulated Diets Enriched by Spinach Extracts for the Broodstock Females, Portunus pelagicus (Linnaeus, 1758).

BACKGROUND AND OBJECTIVE: Spinach extract (Amaranthacea tricolor) is a very prospective feed raw materials to stimulate the molting and growth of crab female broodstock. The purpose of this study was to evaluate the quality of broodstock females, Portunus pelagicus (Linnaeus, 1758) at different levels of spinach extract based on physical, organoleptic and chemical tests. MATERIALS AND METHODS: Four different treatments of spinach extract (0, 250, 500 and 750 ng g-1 crab, respectively) were used in this study. The female crab samples were collected from coastal region of Padang, West Sumatera and placed randomly in four concrete tanks (200×100×100 cm). Each concrete tank consist of five units of plastic box (45.5×32.5×16.5 cm) with the maximum density was one crab per box. RESULTS: The organoleptic test showed that formulated diets enriched with spinach extract (0, 250 and 500 ng g-1 crab) had a smooth texture, pungent aroma and brown. Whereas from the physics test results obtained good water stability (rupture velocity ranged from 89.20-105.40 min and solids dispersion ranged from 4.97-7.17%), hardness (92.66-98.07%) and sinking velocity (3.88-5.88 cm sec-1) (p<0.05). The results also showed that formulated diet enriched with spinach extract doses of 250-750 ng g-1 crab gave a value of delicacy of feed (0.195-0.386 g crab-1 weight/day) which was significantly different (p<0.05) with 0 ng g-1 crab (0.445 g crab-1 weight/day). The chemical test shows the moisture content were 11.60%, ash 9.31%, protein 44.38%, fat 7.64% and carbohydrate 14.46%. CONCLUSION: It was concluded that there was a linear relationship between dose of spinach extracts in formulated diet and rupture velocity and a quadratic relationship between dose of spinach extracts in formulated diet and solid disperse, hardness and sinking velocity and delicacy of feed.

Studies on Biological Test of Formulated Diets Supplementation of Vitamin E for the Broodstock of Females Blue Swimming Crab, Portunus pelagicus (Linnaeus, 1758).

Background: Currently, great progress in the artificial propagation of commercially important   portunid crabs of the genus Portunus has been achieved, and various methods have been adopted in mass-scale hatchery activities. This study analyzed the biological testing of formulated diets with different dose supplementations of vitamin E for the broodstock of female blue swimming crabs, P. pelagicus (Linnaeus, 1758) Methods: Female crab samples were collected from the coastal region of Padang, West Sumatra. The method used in this study was completely randomized design, with four treatment regimens (n=5 crabs each) of dietary vitamin E (0, 300, 600, and 900 IU/kg formulated diets). Results: The results show that the supplementation of vitamin E in the formulated diet had a significant effect (P <0.05) on the absolute weight growth, carapace length and carapace width. Conclusions: Supplementation of vitamin E on in formulated diet causes broodstock blue swimming crab molting, with a percentage value of 40-80% on day 20 and 20% on day 30, with a 100% survival rate.