Production of specific pathogen free larvae from genetically characterized populations of Anadara tuberculosa (Bivalvia), for stock enhancement and aquaculture in the Peru Northeast Biosphere Reserve

Abstract

The pustulose ark, Anadara tuberculosa, is considered as an emblematic species of the east Pacific mangrove ecosystem. The decline of its populations is of increasing preoccupation, in particular in Peru. The use of hatchery-produced larvae for stock enhancement or aquaculture is attractive but raises strong criticisms from an ecological point of view, as it could conduce to loss of genetic diversity in wild populations and favor the disease spreading from hatcheries to the environment. In this works, spat production through traditional aquaculture/biotechnology technologies was associated with pathogen molecular diagnostics and with genetic diversity estimation to produce specific pathogen-free (SPF) larvae from genetically characterized populations. All PCR and nested-PCR diagnostics of common bivalve pathogens, such as Bonamia, Martelia, Perkinsus and OsHV1, led to negative results for healthy or moribund adults and spat samples. Microbiological and molecular analyses realized during mortalities led to identifying a pathogenic Pseudomonas strain present on culture tank walls, in moribund spats and adults´ blood. Population genetic variation was assessed by mitochondrial COI gene sequences which showed 36.7% haplotype diversity. This study with hatchery production, pathology and genetic components for an overexploited native bivalve represents an original model for successful mollusk stock enhancement or/and innovative aquaculture programs.

Early life cycle description and effects of microalgal diets on larval and post‐larval development of the mangrove cockleAnadara tuberculosa(Sowerby, 1833)

“…(The larvae of these treatments were the only ones that reached this stage.) Larvae were stocked at a density of 100 pediveliger.cm −2 as recommended by Diringer et al (2019). The larvae in this stage were kept fed with the same original treatment at a concentration of 75,000 cells.mL −1 .…”

“…The tangible socio‐economic‐ecological impact of its depletion, and the opportunity to produce it in aquaculture systems (Ellis, 1968), has led to the production of A . tuberculosa spat under laboratory conditions with relative success; however, they only suggest general aspects without explaining results on production from the biological‐scientific point of view (Vásquez et al, 2009; Diringer et al, 2019; González et al, 2014). None of them shows a complete larval chronological description.…”

Growth of Oyster (Crassostrea virginica) Larvae in Small-Scale Systems Using an Algae Concentrate Food Source

“…This biofilm appeared at 4 dpf, peaked at 8 dpf, and was not observed after 10 dpf. A pinkish biofilm has been associated with mortality events in other invertebrates [34][35][36] and may support the hypothesis of negative bacterial interactions in these smallscale airlift systems; however, additional experiments are required to test this. The algal accumulation and pink biofilm were not detected in large-scale systems.…”

Evaluation of bacterial strains to improve the productivity of microalgae used in bivalve hatcheries in Peru

“…Furthermore, larval cultures are frequently affected by infectious diseases, primarily of bacterial origin (Diringer et al, 2019;Travers, Boettcher, Roque, & Friedman, 2015). Microalgae are considered the main bacterial entry source into mollusk larviculture, so the microbiological management of microalgal cultures is essential to ensure seed production (Prado, Romalde, & Barja, 2010).…”