According to the invention, it was found that, surprisingly, a feedstuff having a very high abrasion resistance and very high water stability can be obtained when a PUFA-containing biomass having a high sulphate content is used for producing the feedstuff.

According to the invention, it was found that culturing of PUFA-producing cells in a content of sulphate makes it possible to obtain a biomass having high cell stability and thus PUFAs protected against oxidation in a sustained manner, which biomass can in addition be advantageously further processed into a feedstuff.

According to the invention, it was found that culturing of PUFA-producing cells in a content of sulphate makes it possible to obtain a biomass having high cell stability and thus PUFAs protected against oxidation in a sustained manner, which biomass can in addition be advantageously further processed into a feedstuff.

An extruded, pressed or particulate fish feed is described. Also described is a method for reduction of the content of undesired nutrients in water discharged from a fish farm, and a process for increasing the mechanical strength or shear resistance of faeces from fish in a fish farm.

An extruded, pressed or particulate fish feed is described. Also described is a method for reduction of the content of undesired nutrients in water discharged from a fish farm, and a process for increasing the mechanical strength or shear resistance of faeces from fish in a fish farm.

High Specific Mechanical Energy extruder screw assemblies (14, 88, 98) and complete extruders (10, 86, 96) are provided, which include wide-flight intermediate screw sections (104) having axial flight widths greater than the flight widths of the inlet and outlet screw sections (102, 106) on opposite sides of the intermediate sections (104). The intermediate sections (104) provide increased friction and shear serving to enhance the SMEs imparted to comestible food materials during processing thereof.

High Specific Mechanical Energy extruder screw assemblies (14, 88, 98) and complete extruders (10, 86, 96) are provided, which include wide-flight intermediate screw sections (104) having axial flight widths greater than the flight widths of the inlet and outlet screw sections (102, 106) on opposite sides of the intermediate sections (104). The intermediate sections (104) provide increased friction and shear serving to enhance the SMEs imparted to comestible food materials during processing thereof.

According to the invention, it was found that a feedstuff containing an Aurantiochytrium biomass brings about a significant increase in growth in fish.

According to the invention, it was found that a feedstuff containing an Aurantiochytrium biomass brings about a significant increase in growth in fish.

The present invention relates to phytase variants. The present invention also relates to polynucleotides encoding the variants; nucleic acid constructs, vectors, and host cells comprising the polynucleotides; and methods of using the variants.