Growth curves of pigs from six genetic lines were estimated linearly (making use of on-test and off-test weights at ca 35 and 93 kg, respectively) and curvilinearly (making use of these and midtest weights at ca 63 kg). The degree of curvilinearity (D E V N % ) was quantified as the difference between actual mid-test weight and its linear prediction, expressed as a percentage of the latter. D E V N % showed line means from -5 to -2 % , with within-line standard deviations from 9 to 11 % . In the fastest-growing three lines, D E V N % showed h2 values (estimated with a sire-dam model) close to zero while the h2 of linear daily gain (LDG) ranged from 0 .1 3 to 0.21; in the slower-growing three lines, h2 values of LDG and D E V N % were of the same magnitude, ranging from 0.13 to 0.26 and from 0.1 6 to 0.35, respectively. Mean metabolic body weights MBW over the growth trajectory as estimated from on-test and off-test weight only and from these plus midtest weight showed within-line correlation coefficients of ca 0.93. It is concluded that the degree of curvilinearity of the growth curve is a heritable trait in some of the lines. This has implications for the w ay M B W has to be accommodated in selection criteria that attempt to aim for net feed efficiency.
Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume 19. Selection and quantitative genetics; growth; reproduction; lactation; fish; fiber; meat., , 193–196, 1994
|Download Full PDF||BibTEX Citation||Endnote Citation||Search the Proceedings|
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.