关键词: 汉江黑猪, 能量水平, 蛋白水平, 育肥性能, 肉品质, 胴体

Abstract: To optimize the feeding strategy for Hanjiang black pigs during the finishing period and balance their growth performance with characteristic meat quality, this study employed 3 × 2 two-factor experimental design to investigate the effects of different dietary energy levels (12.5, 13.5, and 14.5 MJ/kg) and protein levels (14% and 16% ) on the finishing performance, slaughter performance, and meat quality of Hanjiang black pigs. A total of 90 healthy castrated male Hanjiang black pigs aged 70 days were randomly allocated into 6 groups, with 3 replicates per group and 5 pigs per replicate. The experiment lasted for 120 days. The results showed that: ① Dietary energy level significantly affected finishing performance. The average daily gain (ADG) in the 13.5 MJ/kg energy group (479.08 g) was significantly higher than that in the 12.5 MJ/kg group (P＜0.05), but was not significantly different from that in the 14.5 MJ/kg group (P＞0.05). The feed-to-gain ratio (F/G) in the 13.5 MJ/kg group (3.91∶1) was significantly lower than that in the 14.5 MJ/kg group (P＜0.05). These results indicated that a moderate energy level could improve feed conversion efficiency while maintaining growth performance. ② Dietary protein level significantly affected slaughter performance. The eye muscle area (26.61 cm2 ) and lean meat percentage (42.01%) in the 16% protein group were significantly higher than those in the 14% protein group (P＜0.05), indicating that increasing the protein level promotes lean tissue deposition. ③ An interaction effect between energy and protein on meat quality was observed. The combination of 13.5 MJ/kg energy and 16% protein resulted in the highest intramuscular fat content (4.88%) and marbling score (4.2 points on a 6-point scale), while the backfat thickness (39.67 mm) was consistent with the characteristics of the fat-type Hanjiang black pig breed. The optimal dietary levels for Hanjiang black pigs during the finishing period were 13.5 MJ/kg energy and 16% protein. This nutritional combination not only improved growth performance and slaughter performance simultaneously but also helped maintain and enhance the inherent high-quality meat characteristics of this breed. This study provided a theoretical basis for the resource conservation, breeding, and industrial development of Hanjiang black pigs.

Key words: Hanjiang black pig, energy level, protein level, finishing performance, meat quality, carcass