Genetic parameters for growth traits in pigs estimated using third degree polynomial functions

Authors

• Marja-Liisa Sévon-Aimonen Department of Animal Science, P.O. Box 28, FIN-00014 University of Helsinki, Finland
• Kristina Sternberg Department of Animal Science, P.O. Box 28, FIN-00014 University of Helsinki
• Matti Ojala Department of Animal Science, P.O. Box 28, FIN-00014 University of Helsinki, Finland

DOI: https://doi.org/10.23986/afsci.72774

Abstract

A total of 8745 purebred Yorkshire and Landrace pigs extracted from Finnish progeny test station data was analysed. The pigs were weighed weekly during the test. A third degree polynomial function, age = f(weight), was fitted separately for each pig and was used to describe the growth patterns of individual pigs. Their live weight at the inflection point (LWip) was 72 kg, age at the inflection point (AGEip) 126 d, and maximum daily gain (DGmax) 1111 g/d, on average. The average daily gain from 30 to 90 kg (ADG30-90) was 957 g/d and in the smaller weight ranges (30 to 50, 50 to 70 and 70 to 90 kg) the average daily gains were 829, 1042 and 1046 g/d, respectively. Genetic parameters for growth and carcass traits were estimated using REML with an animal model. The heritability estimates (h2) for LWip , AGEip and ADG30-90 were 0.08, 0.33 and 0.23, respectively, and for smaller weight ranges from 0.14 to 0.21. Fast growing and lean animals had higher LWip than others and the rg between LWip and ADG30-90 DGmax and M% was 0.58, 0.73 and 0.57, respectively. The rg between ADG30-90 and M% was close to zero.