Several hours after stripping we perform final stripping to remove all ripe eggs from the ovaries of the female. This is to prevent that these ripe eggs die inside the ovaries and start to deteriorate. This will harm the fish and can cause death of the broodstock female. The females have to stay in recovery for a couple of days before putting them back to the broodstock tank.Male Clarias gariepinus do not release sperm after treatment with hormones like many other fish species. The males have ripe sperm all year round. The fish should be at least 1 year old to have ripe gonads. A lot of variation can be seen between males of the same age in ripeness and size of testis. In practice farmers sacrify males in order to dissect the testis out of the abdomen. By making incisions in the testis tissue the sperm can be collected. As a consequence new male broodstock needs to be added to the broodstock population sacrificing the males is a big constraint on genetic programmes.