Energy concentration and phosphorus digestibility in single-cell protein and fish meal fed to growing pigs

摘要

Two experiments were conducted to measure the DE and ME concentrations and standardized total tract digestibility (STTD) of P in 2 sources of single-cell protein (SCP) and fish meal (FM). In Exp. 1, the energy concentrations were measured using 8 barrows with an initial mean BW of 36.8 kg (SD = 2.5). A basal diet contained corn as the sole source of energy, and 3 additional diets were formulated to contain 15% of SCP 1 (65.1% CP; produced in Korea) or SCP 2 (75.6% CP; produced in China) and 19% of FM. In Exp. 2, the STTD values of P were measured using 8 barrows with an initial mean BW of 66.7 kg (SD = 4.4). Three experimental diets contained 10% of SCP 1 or SCP 2 and 22% of FM as the sole source of P. A P-free diet was prepared to estimate the basal endogenous loss of P. In both experiments, a replicated 4 x 4 Latin square design was used. Values for the DE in the corn, SCP 1, SCP 2, and FM (3,451, 3,555, 3,313, and 3,515 kcal/kg on an as-fed basis) were not different among the ingredients. The ME in the corn was greater than in SCP 2 (3,376 vs. 2,754 kcal/kg on an as-fed basis; P 0.05). The STTD of P in SCP 1 and SCP 2 were greater (117.5% and 103.1% vs. 48.3%; P 0.05) than in the FM. In conclusion, a source of SCP had less energy value compared with corn, and the 2 sources of SCP had greater digestibility of P than FM.