The study was conducted to determine the main effects of breed, sire, parity, farrowing year and month on preweaning body weight and postweaning traits. The data analysis were the record of 253 male pigs produced from 54 boars of Landrace, Hampshire, ...
The study was conducted to determine the main effects of breed, sire, parity, farrowing year and month on preweaning body weight and postweaning traits. The data analysis were the record of 253 male pigs produced from 54 boars of Landrace, Hampshire, Large Yorkshire and Duroc purebreds at National Animal Breeding Institute from 1978 to 1983. The results obtained in this study are summarized as follows. 1. The effect of breed on preweaning body weight was highly significant at 1% level for body weight at birth, 21 days and 56days, and effect of parity was highly significant at 1% level for body weight at 56 days. 2. On preweaning body weight by breed, Duroc was superior with $1.593{\pm}0.001Kg$ for body weight at birth, and Landrace was superior with $6.227{\pm}0.199$ and $18.590{\pm}0.493Kg$ for body weight at 21 days and 56 days, respectively. 3. The effect of breed on postweaning traits were highly signicant at 1% level for average daily gain, feed efficiency, backfat thickness and days to 90Kg, and the effect of parity was significant at 5% level for backfat thickness. 4. On postweaning traits by breed, Duroc was superior with $876.275{\pm}8.198g$ and $2.754{\pm}0.198$ for average daily gain and feed efficiency, respectively, and Hampshire was thin with $1.969{\pm}0.198$ em for backfat thickness.