Evaluation of Purebreds and Two-Breed Crosses in Swine: Feedlot Performance and Carcass Merit

Abstract

Summary FEEDLOT performance of 941 barrows and gilts and carcass traits of 190 barrows of purebreds and crossbreds of the Duroc, Hampshire and Yorkshire breeds were evaluated for differences between purebreds and reciprocal crosses and for heterosis. Purebred and crossbred litters were farrowed contemporaneously at the Ft. Reno Experiment Station in the 1971 spring and fall farrowing seasons.Rather distinct differences between the pure breeds were evident for most traits. In general, Durocs gained weight more rapidly than Hampshires and Yorkshires while Yorkshires were the most efficient pure breed. Hampshire barrows had less backfat, more loin eye area and more total yield of lean cuts than Duroc or Yorkshire barrows, however Duroc barrows were superior to the other breeds for quality scores of marbling, firmness and color.Heterosis, defined as significant deviation from the average of parental breeds, was found for average daily gain on test (10.2%), age at 100 kg (5.2%) and average daily feed intake (5.9%). There was little evidence for heterosis for carcass measurements or yield of lean cuts. There was positive heterosis for marbling and firmness scores in crosses involving Durocs; however, Hampshire-Yorkshire crosses had negative heterosis for each of these traits.Reciprocal differences between Duroc and Hampshire crosses were small and nonsignificant for all traits. However, most reciprocal differences in crosses involving Yorkshires were significant indicating a difference in the maternal influence of the three breeds.

Maternal Heterosis in Swine: Reproductive Performance and Dam Productivity

“…The gilts were randomly selected from litters produced in Phase I of the project. Information concerning the foundation herds and the production and subsequent performance of the purebred and two-breed cross gilts used in this study has previously been reported (Johnson et at, 1973;Johnson and Omtvedt, 1973b).…”

“…Several studies have shown important differences for many traits among the most common breeds of swine. Recent investigations have demonstrated that several traits exhibit heterosis from crossing and have shown the relative advantage of two-breed crosses compared to purebreds (Smith and McLaren, 1967;Bereskin et al, 1971;Kuhlers et al, 1972;Johnson et a/., 1973;Johnson and Omtvedt, 1973b). The most marked advantage of two-breed crosses compared to purebreds is for preweaning pig liveability and dam productivity traits.…”

Comparison of Three-Breed and Backcross Swine for Litter Productivity and Postweaning Performance

“…Specific objectives were to compare the estimate of one-half individual pig heterosis from this study with earlier estimates of heterosis, and to compare the performance of the three types of crossbred dams and sire breeds for litter traits and postweaning performance. Purebred boars and crossbred females were produced at the OSU swine farm at Stillwater from the purebred Duroc, Hampshire and Yorkshire herds that had been established in 1969 (Johnson et al, 1973). All females farrowing were gilts.…”

Individual and maternal heterosis estimated from single crosses and backcrosses of swine

“…Similar Johnson e_t , 1973;Fahmy et al, 1976). General combining ability estimates for the Duroc and Hampshire breeds indicated significant advantages for loin eye area, percent fat corrected muscle and days required to produce 85 pounds of fat corrected muscle.…”