Finfish Breeding and Hatchery Management

Examination of eggs:
● After the eggs are water-hardened,  take a sample of eggs for assessing their quality
● The fertilized (good) eggs are transparent with a clearly visible nucleus at the centre and look-like pearls.
● The unfertilized (bad) eggs are opaque white and the nucleus disintegrate within one  hour.

Fertilization rate:
● It indicates the quality of eggs and is estimated using the formula :

Fertilization rate (%) = No. of fertilized eggs/Total no. eggs in a sample x 100

Hatching rate:
● It can be estimated by using the formula :
Hatching rate (%) : Total number of newly hatched  spawn obtained/total number of fertilized eggs x 100