AACL Bioflux, vol: 13,3 (2020)
The use of different water volume to measure the growth and survival rates of anguilla bicolor caught from nusawungu riverines, Cilacap, Indonesia
Taufiq-Spj N., Hutabarat J., Trianto A., Wirasatriya A., Indarjo A., Suryono S., Ario R., Pratikto I.
Abstract
Indonesian shortfin eel, Anguilla bicolor, is nowdays one of Indonesia’s leading fishery commodities, but the culture system has not yet been developed. The aim of this study was to determine the effect of different water volumes on specific growth rate (SGR) and survival rate (SR) of A. bicolor specimens of the size of a pencil. Four treatments, consisting in different water volumes in each tank: 0.4 (A), 0.6 (B), 0.8 (C) and 1 m3 (D), were applied in three replications. Approximately 15 kg of elvers (ranging from 1822 g per fish) were used in each treatment (±5 kg for each replication). A. bicolor specimens were fed with a commercial shrimp feed at the dose of 2.2% d-1 (wet basis) or 1.26±0.001% d-1 (dry basis) for a 70 days culture period. Specific individual growth (SGRi), specific biomass growth (SGRb), total biomass growth (TbG), daily weight gain (DwG) and food conversion ratio (FCR) were also calculated. The results showed no significant difference (?>0.05) in individual growth rate (SGRi) between A and B, as well as between C and D. However, there are significant differences in SGRi between A and C, A and D, B and C, and B and D (?<0.05). The patterns of SGRi and SGRb were similar. The highest SGRi result was recorded in the tank A (0.72±0.09% d-1), followed by tanks B (0.71±0.09% d-1), C (0.55±0.06% d-1) and the lowest was recorded in tank D (0.50±0.02% d-1). The survival rate for the culture period had no significant difference among the treatments (?>0.01), however, its value slightly varied around 98%. The highest value of TbG was found in tank A (63.73±9.71%). The best FCR value was also found in tank A (1:1.72±0.26) and the worse was found in tank D (1:2.63±0.13). The recorded values of the water parameters, dissolved oxygen (DO, 6.12±0.366.40±0.27 mg L-1), temperature (28.25±1.86-28.35±1.46ºC) and pH (7.38±0.02-7.64±0.37), were normal during the study. Based on these results, it can be concluded that the growth of the studied specimens increased by decreasing the water volume. The SR of A. bicolor specimens remained unchanged between the treatments. © 2020, BIOFLUX SRL. All rights reserved.
Keyword: FCR; Feeding rate; Seed sources; Specific biomass growth; Specific individual growth