Reproductive traits and on farm performance test record of Duroc, Landrace and Large White sows which were grandparents stock of boars and sows of Nongteng Pig Station.There are 441 sows (3.942 records) which were culled during 1991 to 2001. The sows include must have had at least one farrowing record and two piglets weaned. Genetic parameters for true longevity (TL), functional longevity (FL), lifetime total born (LTB), lifetime born alive (LBA), and lifetime number of piglets weaned (LNW) were analyzed using restricted maximum livelihood (REML) based on multiple traits animal model. Heritability estimates for FL and TL were similar at 0.03. Heritability for LTB, LBA, and LNB were estimated to be 0.16, 0.20, and 0.13, respectively. The genetic correlation estimates between longevities and lifetime productivities ranged from 0.37 to 0.65. The phenotypic correlation between longevities and lifetime productivities were from -0.04 to 0.05. High genetic and phenotypic correlation among LTB,LBA, and LNW were found from 0.65 to 0.98. Small to zero genetic progress would be result from selection for TL and FL due to low heritability of the traits. Indirect selection of other conformation traits related to health, stature, and reproduction such as legs, feet, and udders as well as improving environmental condition might be more effective in improving sows longevity and lifetime productivity.

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