The use of performance test parameters for selection of gilts before their placement into breeding

Abstract

The objectives of the paper were to evaluate carcass value in reared gilts on the basis of carcass analysis during the station test of purebred progeny of pigs and ultrasonically with Sonomark-100 or Piglog-105 instruments in the framework of valid methodology for performance testing, and to verify a pos-sibility of prediction of backfat thickness and/or average daily weight gain since birth and lean meat content of gilts as the elements of objectification for the evaluation of their body condition. In total 54 gilts of two breeds were evaluated: the dam breed Czech Large White and the sire breed Czech Large White – sire line. Four-parameter Richards function was used for growth evaluation. The regression function y = 63.870 – 0.447 bt₁ – 0.510 bt₂ + 0.128 MLLT was applied in ultrasonic instruments for the calculation of lean meat content. We calculated linear regression functions for the conversion of performance testing parameters (gain from birth, average backfat thickness and lean meat content) from live weight on the day of measurement per live weight declared during selections in gilts.