Sow longevity can be improved by selection, but genetic evaluations are challenged for implementation due to the long time interval required to collect complete lifetime data and low reliability of early indicator traits. Present study evaluated genetic parameters for several sow reproductive, stayability and longevity traits. Heritabilities for sow reproductive and longevity traits were estimated from 0.03 to 0.09. Heritabilities of the binary stayability traits were estimated from 0.00 to 0.14. Common litter effect had largest impact in early recorded traits. The results show that fitting the binary stayability traits to normal variance function give the lowest heritability estimates and the binomial variance function with logit function resulted in the highest estimates.
Available at: http://works.bepress.com/kenneth_stalder/2/