关键词: 生产性能, 饲养方式, 杂交(45CC49DB), 猪(49ME), 饲养试验(49MD)

Abstract: Five swine breeds.Landracec (L), Hampsbire (H), Duroc (D).Large White (W) and Yanan (Ya), and seven combinations, L×Ya, H×Ya, D×Ya, W×Ya, L×DYa, H×DYa and W×DYa, were invooved in this study with the total number of 196 pigs.Diet I (for 20-50kg BW) contained DE 2.8Mcal/kg and CP 17-18%, and diet Ⅱ(for 50-90kg BW) contained the same DE and lower CP (12-13%).Before 50kg BW, the feeding patterns of all the groups were five choice feeding.but after 50kg BW the treatiment groups fed within limits while the control groups fed freely.In treatimentgroups, L×Ya, H×Ya.D×Ya, L×DYa and H×DYa were better cross combinations of which feeddingg efficincy were 3.71:3.58, 33.68, 3.58 and 3.28 respectively.The cwerage daity gains of these combinatioms (579g.592g, 581g, 597g and 573g) ones of comtrols, but their carcass lean percentagges (53.8%, 53.3% 54 3% 56.8% and 57.5%) were higher (2.8 1.0, 1.51.1 and 0.8), compared with controls, W×Ya and w×DYa showed higheradipopexis abilith than 5 combination caove, and their lean Percentaes were higher than the ones of comtrols (52.4% vs 49.1% and 54.0% vs 52.5%).The meat qualities of all pigs werenormal.

Key words: PERFORMANCE, FEEDINGG PATTERN, CROSSING, HOGS, FEEDINGE×PERIMENTS