Abstract: A support element for storing crates, wherein the support element is an elongate element having a cross section that is substantially formed in an U-shape, comprising a bottom section and two opposite side walls extending from the bottom section. The side walls each comprise a top portion, forming two elongate supporting areas, whereby the elongate supporting areas are configured to support a crate or a column of stacked crates, The inner side sections of the side walls each comprise a step symmetrically protruding to the inside of the U-shape forming two elongate running surfaces, whereby the elongate running surfaces are configured to support a conveyor system for transporting the crate. The invention further refers to a support system, a storage system and to a rearing unit.