Effects of palm kernel cake and decanter cake combinations on growth performance, carcass traits, growth and nutrient transporter gene expression, and breast meat composition in broiler chickens

This study assessed the impact of varying inclusion levels and combinations of palm kernel cake (PKC) and decanter cake (DC) on broiler chicken performance. A total of 1,260 one-day-old male broilers were randomly assigned to 18 groups, including a control, 5% PKC, 5% DC, and PKC–DC combinations at different ratios (30:70, 50:50, 70:30) and inclusion levels (2–10%). Data were analysed using the General Linear Model (GLM) procedure in Statistical Analysis System (SAS) software. Treatment differences were determined by one-way analysis of variance (ANOVA), and Duncan's Multiple Range Test was used for post hoc mean comparisons at p < 0.05. Inclusion of PKC and DC combinations at 6–10% levels reduced (p < 0.05) body weight (BW) and body weight gain (BWG), and increased (p < 0.05) feed conversion ratio (FCR). Carcass weight and breast relative weight were reduced (p < 0.05) at 8% and 10% inclusion levels. However, hepatic growth-related and intestinal nutrient transporter gene expression were unaffected (p > 0.05). Breast meat composition was unaffected except for ether extract (EE), which increased (p < 0.05) at higher inclusion levels. Overall, PKC and DC combinations can be included up to 4% without adverse effects, while levels ≥ 6% may reduce growth performance.