CROSS+

Introduction

Large rainbow trout of 3,5 kg and more, with unmatched growth potential well pigmented flesh and attractive silvery exterior has become an ever more popular alternative or supplement to the Atlantic salmon and other salmonids in sea farming. In addition to the positive perception of the saltwater reared rainbow trout (steelhead) in the marked, the general characteristics of the rainbow trout gives this species a competitive edge under saltwater conditions and freshwater conditions alike. AquaSearch CROSS+, has been developed for the production of large rainbow trout in both seawater (steelhead trout) and freshwater, but will also be a significant asset to other types of trout production, where unmatched growth rate is important.

Genetic background and breeding

AquaSearch CROSS+ is a crossbreed between AquaSearch CROSS and recent Norwegian AquaGen material, imported by AquaSearch in the form of frozen semen. The current AquaSearch CROSS+ family breeding programme, is being supported by genetic marker assisted selection of broodstock as well as male contribution of various QTL’s on request in commercial batches.

General breeding traits

  • Improved growth rate
  • Continued growth after 2,5 kg
  • Reduced risk of second winter maturation (supported by patented genetic marker use)
  • Silvery exterior
  • Fillet colour (Supported by use of genetic markers)
  • Improved RTFS resistance (supported by use of up to 10 genetic markers)
  • Improved vibriosis resistance (supported by use of genetic markers)

One strain / two breeding lines

Currently two breeding lines of the CROSS+ strain are being maintained to secure furthest possible extended availability during the calendar year. One autumn line and one spring line. The main difference being age of maturation. Pending environmental conditions, feeding rate and light regime the autumn line will mature to some extend second winter, where the spring line is unlikely to mature until third and fourth winter.

Optional breeding traits

  • Additional reduced risk of second winter maturation (marker assisted selection)
  • Additional improved RTFS resistance (marker assisted selection)
  • Additional improved vibriosis resistance (marker assisted selection)
  • Improved white spot disease resistance (marker assisted selection)

General characteristics

When the unique features of AquaGen material is combined with the original AquaSearch SALT genetics, the general characteristics of AquaSearch CROSS+ can be summarized as follow:

  • Specific disease-free origin
  • High hatchability (> 95% guarantied*)
  • * Pending recognized hatching conditions
  • Guarantied all female material
  • High saltwater tolerance.
  • General stress and disease tolerance.
  • Unmatched growth rate
  • Continued growth after 2,5 kg
  • Low feed conversion rate
  • Elongated body shape.
  • Potential high feeding rate
  • Specific improved disease resistance