Finfish Breeding and Hatchery Management (2+1)

Unit 8 - Breeding of trouts

8.3. Brood-stock development

• RBT spawn during spring (January-May), but photoperiodic manipulation can advance or delay maturation and spawning which ensures year-round fry production.
• It does not spawn naturally captivity and in aquaculture systems.
• Eggs are artificially obtained by spawning or stripping females.
• Ripe/fully mature females (3-4 year-old) fish is preferred.
• High quality broodstock is used.
• More number of females is required as fecundity is low.
• Females produce up to 2,000 eggs /kg body weight.
• Eggs are large (3-7 mm)
• Sex ratio 1 : 3 (male and female) are kept separately prior to spawning.
• Since broodstock development is costly, eggs are seldom purchased and hatched.
• Disease-free eggs are purchased. But they should be treated with iodine at 100 mg/l for 10 minutes.
• All-female triploid (sterile) trout produced through gynogenesis and triploidy and all-female progeny produced through 17α - MT treatment and selective breeding are also used for grow-out farming.
  

Race ways where trout brooders are reared