Abstract: A broiler rearing unit comprises an elongate housing which defines a continuous elongate space able to accommodate birds from chicks through to maturity and allow them to exercise, and having a floor 9 which extends longitudinally of, and is movable along, the space so that birds can be transported on the floor to one end of the space for removal from the housing. The floor comprises a series of load-supporting elements 10 which are releasably connected end-to-end and can be successively detached from the remaining elements when they reach the end of the space. Each load-supporting element in turn has drive imparted to it, suitably by a motor driven portable drive assembly, as it reaches the leading end of the floor and the drive is transmitted to the other elements of the floor through the connections between the elements.

Abstract: A working head which is in contact with the bottom of the body of water is mounted at one end of an arm hingedly connected at its other end to a carriage. The carriage is vertically displaceable on the anchoring device, at least in the lower portion of the latter, between a working position in which the arm forms a relatively small angle with the anchoring device and a position in which it is substantially parallel to the bottom of the body of water.