The determination of beginning- and end-of-period live weights of growing pigs

Optimisation of meat production systems depends upon accurate performance assessment. Weigh platforms in electronic feeding stations allow continuous monitoring of individual pig weight change. Such a system was compared with a conventional mechanical scale with the general result: feeding station weight (kg) = 1.02 (0.010) scale weight - 1.65 (0.766). As compared with the conventional scale measurement at start and at finish of test, back extrapolation of daily weights collected over time in electronic feeding stations may give an improved estimate of start weight, and forward extrapolation an improved estimate of final weight. Regression predictions suggest this to be the case for final weight, but for start weight both systems are open to error due to variation in weight in the early days of test. However, such variation (and its diagnostic utility) is only observable with a system that continuously monitors weight. (C) 2002 Society of Chemical Industry.