A Comparison of the Effects of Two Prey Enrichment Media on Growth and Survival of Pacific Bluefin Tuna, Thunnus orientalis, Larvae

Abstract

Three experiments were conducted to investigate the growth, survival, and standardized cohort biomass of Pacific bluefin tuna, Thunnus orientalis, larvae fed nutritionally enhanced prey during the first week of feeding using two commonly used, commercially available enrichment media, AlgaMac Enrich and Marine Glos. T. orientalis larvae exhibited exponential growth in standard length and dry weight. The daily specific growth rates in length and weight are the first reported for T. orientalis larvae and the averages ranged from 3.8 to 4.1% and 27.5%, respectively, for larvae in the AlgaMac treatment and from 4.1 to 6.1% and 31.5%, respectively, in the Marine Glos treatment. Average daily growth rates in length ranged from 0.16 to 0.23 mm/d for larvae in the AlgaMac treatment and from 0.17 to 0.27 mm/d for those in the Marine Glos treatment. Daily growth rates in length were similar to those reported for other tuna larvae reared in the laboratory but slower than most published estimates for larval tunas in situ at similar water temperatures. Mean prey number per gut was positively associated with mean prey level in the tank. Both enrichment media appear to be good sources of nutritional improvement of planktonic prey for T. orientalis larvae.

Advancements in hatchery production of red snapper Lutjanus campechanus: Exclusive use of small strain rotifers as initial prey for larval rearing

“…Along with copepods, enriched rotifers have been used effectively as first feeding organisms for snapper species (Duray et al, 1996; Ibarra‐Castro et al, 2020), small mouth‐gape marine fish larvae (Alvarez‐Lajonchère et al, 1996; Geng et al, 2019; Wullur et al, 2011), and even challenging species that also exhibit rapid yolk‐sac absorption and high nutritional demand, such as scombrid larvae (Blanco et al, 2020; Kaji et al, 1999; Sawada et al, 2005; Stein et al, 2018). S‐strain rotifers are relatively easy to culture in large scale, compared to copepod species (Saillant et al, 2013).…”

Biochemical Changes Occurring in Yellowfin Tuna Eggs during Embryonic Development

“…Various studies have reported on the captive propagation of YFT [3][4][5], the food selectivity of larvae [6,7] age validation and growth and survival [8,9], the enzyme activities and amino acid composition of early juveniles [10], and the optimum water-quality parameters for larval growth [11]. However, high mortality at the larval and early juvenile stages was shown by Lang et al [12] and Kaji et al [13,14] for both YFT and Pacific bluefin tuna (PBT, Thunnus orientalis) [15,16].…”