Reproduction of 3/4 White Composite and 1/4 Duroc, 1/4 Meishan, 1/4 Fengjing, or 1/4 Minzhu gilts and sows.

Females were either Duroc, Meishan, 1/4 Fengjing, or 1/4 Minzhu, and the remainder were 3 /4 White Composite. A greater percentage of Fengjing crosses reached puberty than Duroc or Minzhu (P .05) from other breed types. After adjusting for differences in percentage detected owing to termination of observation for estrus, breed types ranked Fengjing, Meishan, Minzhu, and Duroc from youngest to oldest at puberty with approximately 14 d between adjacent breed types. Meishan and Fengjing crosses had a greater ( P .05) for litter or uterine traits measured on gilts slaughtered at 60 or 100 d of gestation. Total number of pigs born was greater ( P .05) among breed types. Duroc crosses were heavier (P .05) for backfat thickness at those times. Breed types did not differ ( P >.05) for the ratio of litter gain from 0 to 28 d/total Mcal or any of the component traits in the ratio. Postweaning estrus activity, conception rate, and litter and uterine traits of sows bred for second parity were not affected (P >.05) by breed type. These analyses indicate that crossbred gilts containing Meishan, 1/4 Fengjing, or 1/4 Minzhu will reach puberty earlier, have larger litters, and weigh less at first parity than gilts containing Duroc, but they do not have any significant advantage in litter size at second parity.