Cage culture of tropical eels, Anguilla bicolor pacifica and A. marmorata juveniles: Comparison of growth, feed utilization, biochemical composition and blood chemistry

Abstract

This study examined the performance and suitability of two tropical anguillid eels, Anguilla bicolor pacifica and A. marmorata, under cage culture conditions. Juvenile eels (1.73 ± 0.14 g body weight) of each species were stocked in triplicate hapa net cages (1 × 1 × 1.5 m; 30 eels/cage) suspended in outdoor tanks. Growth, feed utilization, biochemical composition and blood chemistry of the two species were compared after 210 days. Except for survival, mean final body weight (FBW), weight gain percentage (WG), specific growth rate (SGR) and yield of A. bicolor pacifica (64.51 ± 13.07 g, 3514 ± 690%, 2.14 ± 0.12%/day, 1534 ± 380 g/m3) were significantly higher than that of A. marmorata (7.77 ± 2.90 g, 356 ± 125%, 0.89 ± 0.16%/day, 178 ± 89 g/m3). In comparison with A. bicolor pacifica, significantly lower feed intake (FI), feed efficiency (FE) and protein efficiency ratio (PER) observed in A. marmorata suggest the need to develop eel diets with feeding stimulants to improve feed acceptance. Biometric indices, body proximate and amino acid composition were not significantly different between the two species. However, serum glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and total protein (TP) in A. bicolor pacifica were significantly higher than that in A. marmorata. These findings suggest that the differences in growth performance and feed utilization between the two anguillid eel species are related to feed palatability, and that A. bicolor pacifica appears to be a suitable species for cage culture because of its faster growth.

Effect of size grading on growth of yellow Pacific shortfin eel (Anguilla bicolor pacifica)

“…Tanks were supplied with deep well water at 1–2 l min −1 , provided with aeration and covered with double‐layered black nets to reduce light intensity (Hirt‐Chabbert et al ., 2014). Eels were fed twice daily (08.00 and 17.00 hours) at apparent satiation with a formulated eel powder diet (49.77% crude protein, 10.21% crude fat) made into a paste (Aya & Garcia, 2022). The formulated eel diet (in powder form) was made into a paste by adding water (700 ml kg −1 diet), and the dough mixture was mixed in an electric mixer for 15 min until the desired consistency was achieved (Aya & Garcia, 2022).…”

“…The Pacific shortfin eel Anguilla bicolor pacifica is one of the commercially important tropical anguillid eel species distributed in Indonesia, the Philippines and Viet nam (Aoyama et al ., 2018; Crook, 2014; Gollock et al ., 2018; Marini et al ., 2021). The culture of this eel species has drawn considerable interest among eel farmers in the Philippines because it commands a higher price in the market as an export commodity (Arai, 2014; Cuvin‐Aralar et al ., 2019) and exhibits faster growth (Aya & Garcia, 2022). A. bicolor pacifica exhibits growth variation during the elver stages, and frequent size grading of every 2 weeks is done manually or by using bar graders in nursery farms (Cuvin‐Aralar et al ., 2019).…”

Alternate Day Feeding as a Cost-effective Strategy for Tank Culture of the Pacific Shortfin Eel Anguilla bicolor pacifica

“…The effect of alternate day feeding on the production parameters of tropical anguillid eels is yet to be determined. To examine production and economic effects of feed management strategy for tropical anguillid eels, the Pacific shortfin eel A. bicolor pacifica was chosen due to its fast growth rate (Aya and Garcia 2022).…”