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Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/6/1998 Publication Date: N/A Citation: N/A Interpretive Summary: This study compared the survival, growth, feed efficiency and carcass traits of pigs that were 7/8 White Composite and 1/8 Duroc, 1/8 Meishan, 1/8 Fengjing or 1/8 Minzhu. Results show that pigs that are 1/8 Chinese (Meishan, Fengjing or Minzhu) have a significantly slower growth rate and a small, statistically nonsignificant decrease in yield of trimmed lean cuts relative to 1/8 Duroc crosses. In previous research, only the 1/4 Meishan and 1/4 Fengjing dams of these pigs had small advantages over 1/4 Duroc females for age at puberty and litter size at first parity and no advantage in litter size at second parity. The relative value of reproduction, growth and carcass traits will vary among producers. However, these results would suggest that relative to similar Duroc crosses, the decrease in growth rate and slight decrease in yield of trimmed lean cuts of 1/8 Chinese pigs would likely offset the slight reproductive advantage of the 1/4 Chinese dams in overall economic efficiency. Technical Abstract: Pigs were the progeny of White Composite boars mated to gilts that were either 1/4 Duroc, 1/4 Meishan, 1/4 Fengjing, or 1/4 Minzhu and the remainder 3/4 White Composite. Duroc, Meishan, and Minzhu crosses did not differ for survival at birth, 14, and 28 d. Fengjing crosses had a lower survival rate at all three ages than Duroc and Meishan crosses. Duroc crosses were heavier than Chinese crosses at birth. At 56 d, Duroc and Meishan crosses did not differ for BW, but both were heavier than Minzhu crosses. Duroc crosses were heavier than any of the Chinese crosses at 98, 126, and 154 d of age. The effect of breed type was not significant for average backfat thickness of gilts at 99.7 kg. Duroc crosses consumed the most feed and Fengjing crosses consumed the least per day over each interval and over the total period. At 184 d of age, breed type was not significant for measures of carcass fat thickness, marbling score, color score, and firmness score. At 184 d of age, weights of all carcass cuts were heavier for Duroc than Chinese crosses except the nonsignificant, lighter untrimmed loin weight from Minzhu crosses. There were few significant differences among breed types when carcass traits were compared at a constant carcass weight, although Duroc crosses generally had more desirable mean values. Relative to similar Duroc crosses, these results suggest 1/8 Chinese would have a significant decrease in growth rate and statistically insignificant decrease in yield of trimmed lean cuts at a constant carcass weight. |