Documentation

The new EasyHatch substrate and the new CompHatch hatching cabinet have been compared with the traditional method which is traditionally used for salmon at the installation at Kvingo as control: Astro Turf substrate in 1m tanks with hatching inlays. At Fister Smolt, only substrate was compared to Astro Turf, both in 1m tanks with adapted hatching inlays as well as in 0.78m2 round hatching inlays placed in 1m tanks. With reference to growth in the yolk bag phase and through initial feeding, no significant differences were recorded at Fister Smolt between the two types of hatching substrate. At Kvingo, decisively better values as to survival up to the age of 4 weeks into the initial feeding were recorded for EasyHatch. Up to 21% lower mortality than with Astroturf, depending on the type of incubation unit. The weight of the fish 4 weeks into the initial feeding showed a small difference, median weight of 0.77g for EasyHatch compared to 0.82 g for Astroturf. As to practical operations, EasyHatch hatching substrate came out best with clear advantages in the following areas: simple assembly, reduced risk of fry getting caught between the mat and the bottom of the tank, cleaning/picking of dead fry during operations, cleaning after the end of the season, total hygiene during operations. The project proves that EasyHatch has a capacity of at least 33 % more yolk bag fry than Astroturf without compromising survival and growth. The hatching cabinet CompHatch with EasyHatch gave 21% lower mortality than 1m tanks with Astroturf. 1m tanks with Astroturf weight at initial feeding at 0.17g compared to 0.16g for CompHatch. The hatching cabinet EasyHatch requires considerable less space than a 1m tank and the roe incubation in an eight tray/drawer cabinet is carried out in approximately 25% of the area compared to
1m tanks with Astroturf. CompHatch has a practical and well arranged system for adjusting and visualizing the water consumption per unit in the cabinet which is not available for a 1m tank. CompHatch is quicker to care for all in all.