Growth and biochemical composition of juvenile green abalone Haliotis fulgens fed rehydrated macroalgae

Abstract

Under controlled laboratory conditions, juvenile green abalone Haliotis fulgens were fed rehydrated natural feeds to determine the effects on growth, survival, feed efficiency and biochemical composition of the digestive gland and muscle. Five macroalgae, Ulva sp. (Chlorophyta), Eisenia arborea, Macrocystis pyrifera, Egregia menziesii (Phaeophyta) and Porphyra perforata (Rhodophyta) were tested. The macroalgae promoted growth, although, depending on the species, there were considerable differences in growth, feed efficiency and biochemical composition of the digestive gland and muscle. Mean growth rate in length and weight and survival rate varied within the ranges 1.6–15.1 μm day−1, 1.4–8.1 mg day−1 and 44–69%, respectively. Significantly, higher growth rates were obtained from Egregia menziesii, M. pyrifera and P. perforata. Feed conversion ratio ranged from 6.5 to 42.4 for P. perforata and Ulva sp. Protein, carbohydrates and lipid contents in the digestive gland ranged from 113 to 180, 98.3 to 448 and 17.2 to 23.3 mg g−1, respectively. In muscle, the ranges were 66.9–123, 9.5–23.2 and 2.8–3.9 mg g−1, respectively. This study shows that rehydrated Egregia menziesii, M. pyrifera and, particularly, P. perforata are more efficient in promoting growth than Ulva sp. and E. arborea which match results reported by other authors when using the same fresh macroalgae.

Status of the digestive gland and feed index in juvenile green abaloneHaliotis fulgensfed rehydrated macroalgae

“…); however, in our treatments, the red algae P. perforata produced growth rates that were not significantly different than brown algae (Pérez‐Estrada et al . ). Moreover, the feed efficiency of P. perforata was superior to brown algae.…”

“…Gross energy was determined using a bomb calorimeter (Model 1261; Parr Instrument, Moline, IL, USA), as described in Pérez‐Estrada et al . ().…”

“…Before weighing the specimens, excess water was removed by blotting with paper towels (Pérez‐Estrada et al . ).…”

“…Natural feed of abalone is a mixture of macroalgae, diatoms and biofilm; however, little is known of the important nutrient requirements of juvenile abalone in terms of energy level, proteins and micronutrients (Pérez‐Estrada et al . ). One major concern of all aquaculture enterprises is to satisfy the nutritional requirements of the organisms during the first stages of life.…”

“…Pérez‐Estrada et al . () found that E. menziesii , M. pyrifera and P. perforata are more efficient in promoting growth in juvenile green abalone than Ulva sp. and E. arborea .…”