Abstract: Birds transported by an overhead poultry shackle line suspended by their hocks are led into engagement with bird orientation devices moving with a horizontal endless conveyor element below and parallel to the path of movement of the overhead shackle line. The orientation devices, which are under influence of an endless camming mechanism, engage the birds through openings between their legs and pull the birds to positions of stability under tension as the birds are transported through a relatively stationary severing blade along their path of movement to achieve clean halving of each bird in succession across the backbone between the breast and hind quarters. The machine is adjustable to process birds of varying sizes.