UNDERWATER FISH EGG SEPARATION

THE SEPARATION OF FISH EGGS, LIVE FROM DEAD, IS A CONTINUINGPROBLEM FOR FISH HATCHERIES. SORTING OUT UNFERTILIZED EGGS THAT HAVE NOT CHANGED FROM ORANGE TO WHITE (BLANKS) REMAINS AN UNSOLVED PROBLEM. TRADITIONAL MECHANICAL EGG SORTERS INSERT FISH EGGS INTO DISKS OR DRUMS, THEN COMPARE A SMALL AREA OF THE EGG TO THE BACKGROUND USING REFLECTIVE SYSTEM TODIFFERENTIATE LIVING FROM DEAD EGGS. AIR PRESSURE IS USED TO REMOVE THE EGG FROM THE SORTER. PHYSICAL DAMAGE TO THE EGG IS ALWAYS A DIFFICULTY. IF THE EGGS COULD BE SORTED UNDER WATER IN TUBES, USING BOTH REFLECTIVE AND THROUGH-BEAMDENSITY SORTING, MUCH PHYSICAL DAMAGE WOULD BE ELIMINATED AND BLANKS COULD POSSIBLY BE DETECTED AND DISCARDED.