Energy Values and Standardized Ileal Digestibility of Amino Acid in Fermented Cottonseed Meal Fed to Growing Pigs

To evaluate the nutritional value of fermented cottonseed meal (FCSM) for growing pigs, ten representative FCSM samples were collected and assessed in two experiments for the standardized ileal digestibility (SID) of amino acids (AAs) and for digestible energy (DE) and metabolizable energy (ME). In Experiment 1, 11 growing pigs (Duroc × Landrace × Yorkshire, 25 ± 1.8 kg) fitted with a T-cannula were assigned to an 11 × 6 incomplete Latin square design, with 11 diets (one nitrogen-free diet and 10 diets containing FCSM as the sole nitrogen source) and 6 periods. All diets contained 0.30% Cr2O3 as an indigestible marker. Experiment 2 used 22 healthy crossbred barrows with an initial body weight of 45 ± 2.3 kg. A replicated 11 × 3 incomplete Latin square design was adopted, comprising 11 dietary treatments and 3 periods. The dietary treatments included a corn–soybean meal basal diet (control) and 10 FCSM-containing diets. The results demonstrated marked variation among FCSM samples in terms of chemical composition and energy content. The mean Ca/P ratio was 0.32. The average DE and ME were 11.20 MJ/kg (range 9.69–12.65 MJ/kg) and 10.68 MJ/kg (range 8.55–11.84 MJ/kg), respectively. The SID values for Lys, Met, Thr, Trp and Val were 65.90% (60.01 to 68.92%), 77.34% (74.48 to 81.78%), 68.10% (59.97 to 72.02%), 72.12% (70.25 to 73.62%), and 75.50% (68.60 to 78.65%), respectively. Stepwise regression analysis generated prediction equations for estimating DE and ME from chemical composition. These data fill a gap in energy and amino acid digestibility parameters for FCSM, provide a basis for precision diet formulation, and indicate the need to supplement limiting amino acids and optimize the Ca/P ratio.