Finfish Breeding and Hatchery Management

Unit 6 - Breeding of common carp

6.3. Selection of broodfish and breeding technique

• Artificial breeding is undertaken to enhance fry survival.
• Common carp is an asynchronous multiple spawners, releasing eggs in batches.
• Mature brood-stock is identified based on their morphological characters.
• Male has round abdomen and whitish genital opening; oozes milt when pressure is applied on abdomen.
• Female is stout, with soft and swollen abdomen; a few ova may ooze out when pressure is applied on abdomen.
• Mature male and female are released at a ratio of 2 : 1 in a cement cistern (25 m³) with running water.
• Aquatic plants like Hydrilla or Vallisnaria or Eichhornia, etc. are used substratum in the cistern for the attachment of eggs.
• The plants are disinfected with a solution of KMnO₄ and used at a ratio of 1:2 (female : substratum.
• In South-East Asian countries, kakabans (plant fibres, normally coconut or palm, nailed between two pieces of bamboo) are used as substratum for the attachment of eggs.
• The weight of female brooder is taken before and after spawning in order to estimate quantity of eggs released, allowing 5-10% towards loss of weight due to excreta.
• The total quantity of eggs released can be calculated using the formula: Loss in weight (g) x 700, where, 700 is the number of eggs per g ovary weight.
• After spawning, the brooders are removed from the tank, disinfected and transferred to a prepared pond.
  

Common carp attached to Hydrilla being released in a pond for hatching