The use of an electronic labelling system for livestock enables the animals to be automatically identified with stationary antenna systems. In the present study, the recognition system for reading individual transponders from a group (bulk reading), already in use in other industrial sectors, was tested with fattening pigs. To evaluate different antenna systems, transponders mounted on a plastic plate were moved by a newly developed test bench and the movement of a group of pigs was simulated. The focus here was on the identification certainty (read rate) of the transponders guided through the reading field in different numbers, direction and speed. In addition to standardised (ISO) transponders, ones with an anti-collision algorithm (AC transponders) were also used. On average for the variants tested, between 43 and 48 per cent of the AC transponders and between 68 and 85 per cent of the ISO transponders were automatically identified in the simulation of a group of weaners, rearing piglets and fattening pigs. A very highly significant correlation with the read rate was determined for the explanatory variables of ear-tag type, direction and speed. The results for reading individual animals from the group highlighted the potential of this technique. Owing to insufficiently high read rates, however, it is not yet ready to be used in practice.
