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Journal Articles - UP - MSI

Permanent URI for this collectionhttps://repository.unesco.gov.ph/handle/123456789/50

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Has files: NoScientific name: search.filters.scientificname.Amusium pleuronectes

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    Notes on the induced spawning and larval rearing of the Asian moon scallop, Amusium pleuronectes (Linné), in the laboratory
    Belda, C. A.; Del Norte, A. G. C. (Elsevier, 1988-08)
    Sexual and chemical stimulations were effective in inducing the scallop, Amusium pleuronectes (Linné), to spawn sperm only, whereas thermal stimulation was not at all successful. Chemical stimulation consisted of serotonin injections into the ripe gonads. Fertilizable eggs were obtained by stripping gametes from the ovaries. Cleavage of zygotes (72.4 μm mean diameter) occured 1 h after fertilization. Trochophores (58.9–111.2 μm in length) and straight-hinge veligers or D-veligers (80.0–130.2 μm) were observed in less than 24 h. Five days after fertilization, the umbone stage (101.6–169.1 μm) was reached. Crawling pediveligers (174.0–250.0 μm) appeared after 9 days. Seawater in the culture vessels was changed 24 h after fertilization and every other day thereafter. The larvae were fed on Isochrysis galbana (Tahitian strain) at an initial concentration of 30 cells/gml.
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    Aspects of the growth, recruitment, mortality and reproduction of the scallop Amusium pleuronectes (Linné) in the Lingayen Gulf, Philippines
    Del Norte, A. G. C. (Informa UK Limited, 1988-11)
    Growth, recruitment, mortality and reproduction were investigated in the Asian moon scallop, Amusium pleuronectes (Linne) from the Lingayen Gulf, Philippines. Allometric relationships were defined by comparing different shell dimensions, as well as body weight proportions including total weight with shell, visceral weight, adductor muscle weight and gonad weight. Use of the von Bertalanffy-based ELEFAN I program yielded estimates of growth parameters equivalent to H ∞ = 106Dimshell height and K = 0.92 per year, with approximate longevity for the species of about 2 years. Recruitment, as derived using the ELEFAN II program, occurred throughout the year, but showed a pattern consisting of one major and one minor pulse separated by an 8- and 4-months interval. Fishing mortality (F = 5.3) was higher than natural mortality (M = 1.9). Spawning occurred throughout the year, with one major peak in February and one minor peak between July and September, thereby providing some biological basis to the recruitment pattern indicated. Protandry and size at sexual maturity (54 mm) in the species were confirmed.