Investigation on the Relationship between Feeding and Growth Traits of Large White Pigs by Canonical Correlation Analysis

In order to investigate the inherent relationship between feeding and growth traits, 288 Large White pigs (71 males and 217 females) with initial body weight of 30 kg (27~33 kg) were selected to test the feeding and growth traits during 30~100 kg body weight by using automatic feed intake recording equipment (FIRE) system, and the correlations between 6 feeding traits and 3 growth traits were investigated by simple and canonical correlation analysis. The results showed that number of visits per day (NVD) of male pigs was more than that of female significantly (P0.05), but feed intake per visit (FIV) and feed conversion rate (FCR) of male were lower than those of female significantly (P0.05 or P0.01). In both sexes, significantly positive correlations were found between FIV with daily feed intake (DFI) and average daily gain of 30~100 kg (ADG) (P0.05 or P0.01), but negative correlations were showed between the two traits and days to 100 kg body weight (D100) (P0.05 or P0.01); FCR had very significant positive correlation with D100 but negative correlation with ADG (P0.01).In male pigs, the first and second canonical correlation coefficients between feeding and growth traits were 0.860 4 (P0.01) and 0.627 7 (P0.01), respectively, and represented 98.08 percent for the total correlation between the two kinds of traits; in female pigs, the first and second canonical correlation coefficients were 0.727 8 (P0.01) and 0.532 2 (P0.01), and represented 95.75 percent for the total correlation. It indicated that the feeding trait had a stronger correlation with growth trait in Large White pigs. The main causes for the correlation between feeding and growth traits were the correlations of DFI, FIV with FCR and ADG in male pigs, but the correlations of DFI, TFI with D100 and ADG in female pigs. In pig breeding and production, it expected to gain higher weight gain speed and lower feed consumption per-unit weight gain, by increasing the feed intake through breeding and ration optimization approaches, and further increase the efficiency and benefits of pig production.