Growth, agar production and nutritional composition of red seaweed Gracilaria corticata co-cultured with Litopenaeus vannamei under zero water exchange system

Integrated culturing of Gracilaria corticata and Litopenaeus vannamei was surveyed under zero water exchange system in a 45- day period. Water temperature, pH and salinity were measured each 3- day. At the end of culturing period, all seaweeds were separately weighted, dried and their protein, fat, carbohydrate, ash, agar percent and jell strength were measured. The maximum SGR of G. corticata (1.23 ± 0.07% day-1) was observed in treatment S1A1 (25 shrimp per m2 and 200g seaweed per m2) but the maximum agar percent (17 ± 0.2 %) and the maximum agar production (11.21±0.21 gm-2(were observed in S1A2. The maximum jell strength was observed in wild seaweed. Contents of protein, ash, fat and carbohydrate ranged 19.54- 21.31, 33.98 – 35.41, 1.94-2 and 41.95- 43.61% respectively. According to the results, G. corticata can be considered as an important source of protein and carbohydrate.