Possibility of self-fertilization during hatchery culturing of giant clam, Tridacna crocea
| Autor: | Ken Inoue, Reiko Fuseya, Masaya Katoh, Takeo Kurihara |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Larva
animal structures Ecology Ejaculation business.industry Giant clam Zoology Aquatic Science Biology Tridacna crocea Oceanography biology.organism_classification Hatchery Fishery Aquaculture Self-Fertilization embryonic structures Laboratory experiment business Ecology Evolution Behavior and Systematics |
| Zdroj: | Plankton and Benthos Research. 5:11-16 |
| ISSN: | 1882-627X 1880-8247 |
| Popis: | Giant clams are simultaneous hermaphrodites and are assumed to ejaculate first and, after completely stopping ejaculation, release eggs. In the seed production method aimed at preventing self-fertilization, each adult clam is induced to ejaculate in a tank and then release eggs in another tank. Giant clams, however, have recently been suggested to continue ejaculation for a period after the beginning of egg release. The overlap between ejaculation and egg release might lead to self-fertilization in the tank used for egg release, especially for the eggs released just at the beginning of spawning. We examined the possibility of such self-fertilization for the giant clam Tridacna crocea and obtained three results. (1) In observations with the naked eye in a laboratory, 2 of 38 T. crocea simultaneously ejaculated and released eggs. (2) In a laboratory experiment, 1.5 to 80.0% of eggs released from each adult clam developed into D-shaped larvae without artificial cross-fertilization. Such development occurred more frequently for the eggs released earlier from each adult clam than for the eggs released later from the clam. (3) In observations at a hatchery, 2 to 94% of the eggs released from 4 of 5 adults were found to develop into D-shaped larvae without artificial cross-fertilization. The three results suggest that at least some T. crocea adults continue ejaculation for a period after starting spawning eggs, which causes self-fertilization. |
| Databáze: | OpenAIRE |
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