Effects of Dietary Metabolizable Energy and Crude Protein Levels on Growth Performance, Carcass Traits, and Meat Quality of Goslings from 35 to 63 Days of Age

Dietary metabolizable energy (ME) and crude protein (CP) are key determinants of production efficiency in geese; however, their combined effects during the rapid growth phase are not well defined. A total of 240 male goslings were assigned to four treatments in a 2 × 2 factorial arrangement, with six replicates per treatment and 10 birds per replicate. We used a 2 × 2 factorial design to evaluate two ME levels (11.20 vs. 11.65 MJ/kg) and two CP levels (16% vs. 14%) in goslings from 35 to 63 days of age. Growth performance, carcass traits, meat quality, serum biochemical indices, and instrumental taste attributes were measured. Increasing ME increased body weight at day 63 and average daily gain (<i>p</i> < 0.05), whereas average daily feed intake and feed-to-gain ratio were not affected. Most carcass traits were unchanged; however, leg muscle percentage differed between ME levels (<i>p</i> < 0.01) and was higher in the 11.20 MJ/kg group. Meat color responses were muscle- and time-dependent: breast b* at 45 min postmortem was affected by ME and CP (<i>p</i> < 0.001), and leg color traits at 45 min exhibited significant ME × CP interactions (<i>p</i> < 0.05). Postmortem pH, water-holding capacity, and shear force were largely unaffected by dietary treatments. Serum glucose showed a significant ME × CP interaction (<i>p</i> = 0.001), and triglyceride concentration was influenced by both ME and CP (<i>p</i> < 0.01), with lower values observed at higher ME and lower CP. Instrumental taste attributes did not differ among treatments (<i>p</i> > 0.05). In conclusion, modest changes in dietary ME and CP modulated growth and selected carcass, color, and metabolic traits without compromising key technological meat-quality parameters. These results indicate that, during 35-63 days of age, the higher-ME diet (11.65 MJ/kg) combined with a moderate CP reduction to 14% can be considered a feasible formulation option under the conditions of this study.