FISH REPRODUCTION AND DEVELOPMENT (1)

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FISH REPRODUCTION AND DEVELOPMENT
Development
Stages
Reproduction
Egg - lt0.5 mm - 10 cm variable shape,
attachments variable buoyancy water
hardening Embryo - dependent on mother or yolk
sac for food (free embryo) Larvae - not
fully functional, may look totally unlike adult
ends when axial skeleton is formed Juvenile -
small functional individual, immature Adult
- reproductively mature

• Nearly all fish reproduce by sexual
  reproduction-the fusion of sperm produced from
  testes and eggs produced from ovaries.Fertilizatio
  n is external in most species.

Types
Indirect development (perch) - larval stages go
through trophic phases different from
adults Intermediate (salmonids) - embryonic
stage with yolk virtually no larval stage Direct
development (gobies) - juvenile is fully
functional miniature of adults (no larval stage)
Asexual Reproduction (Parthenogenesis)
REPRODUCTION

• There are 3 modes of sexual reproduction
• Oviparity Egg Laying
• OvoviviparityLivebearing,no maternal nourishment
  
• ViviparityLivebearing with maternal nourishment