About Lesson
Spawning
- Usually, when two doses are administered to the females, the spawning generally occurs 4-6 hours after the second injection.
- The female release eggs which are then fertilized by the milt released by the males in water.
- Usually, entire spawning occurs within a very short time.
Incubation and hatching
- Includes the process by which the fertilized eggs obtained from the brood fish develops through smooth embryonic development to hatching and subsequent stages.
- The fertilized eggs are generally collected after water hardening and transferred to special incubating devices for hatching.
- Hatching devices includes from simple happa to Zoug jars with temperature-controlled water supplies but the common is circular incubation tank.
Incubation period of Chinese and indigenous major carps
|
Fish Species |
Temperature (0C) |
Incubation period (hours) |
|
Grass carp, Silver carp |
22-25 |
32-35 |
|
Bighead carp |
26-28 |
24-28 |
|
Rohu, Mrigal, Catla |
26-31 |
16-18 |
|
Common carp |
18-20 |
100-144 |
|
African catfish |
20-22 |
70-80 |
|
Sahar |
28-31 |
46-48 |