Once a month the litter reports from the farms are reviewed to ascertain the average number of piglets born per boar. If there are too few reports per boar, further litter data are requested from the farms. Boars whose litter sizes are too small are tested for RT (reciprocal translocation). If the RT result is positive, the boar is culled. If the RT result is negative and there is a sufficient number of small litters, the boar is also culled.
As well as the litter assessment, the average number of piglets per litter per boar is also recorded.
Once the piglets are born, the date of birth and the number of live born and still born piglets is electronically recorded. This data in itself allows the fertility of the boar to be established and boars with low results to be culled.