Amino acid release patterns of growing pig diets formulated with different dietary protein sources

Effects of protein content and the inclusion of protein sources with different amino acid release dynamics on the nitrogen utilization of weaned piglets

“…In addition, the poor digestibility of plant-based proteins in piglets may be due to incomplete development of digestive enzymes [ 24 ]. Abdallah et al [ 13 ] compared the in vitro digestion of SBM, fish meal, CGM, and fermented SBM over 28 h, and found that the FAA release from CGM diet was significantly lower than the release from the other diets at between 8 and 20 h, and did not reach the same level until 24 to 28 h, which indicates that AA are released more slowly from CGM. In the present study, we found that the peak AA release from CAS during trypsin digestion was within 0 to 4 h, whereas the peak AA release from CGM was at 16 to 20 h. The slow release of AA from CGM proteins, in contrast to the fast release of the added FAA, exaggerates the degree of AA imbalance associated with this diet.…”

“…Following the methods of Bai et al [ 12 ] and Abdallah et al [ 13 ] which was modified from the method developed by Boisen and Fernández [ 11 ], 1 g of each feed sample (measured to 0.001 g) was placed in 100 mL conical flasks, with three replicates per diet. Ten milliliters of freshly prepared 1 mg/mL pepsin (pH 2) and 0.5 mL chloramphenicol solution (0.5 g chloramphenicol in 100 mL ethanol) were added to the conical flasks, which were sealed and incubated in a water bath oscillator at 39°C for 4 h. At the end of the incubation, the conical flasks were removed, 10 mL phosphate buffer (pH 6.8) was added, and the pH was adjusted to 6.8 using 1 M NaOH.…”

“…As previously described by Abdallah et al [ 13 ], an Acquity ultra-high performance liquid chromatography (UPLC) tunable ultraviolet system (Waters, Milford, MA, USA) was used. The chromatographic column was an AccQ·Tag Ultra column (2.1×100 mm, P/N: 186003837), mobile phase A was 10% AccQ·tagUltra eluent A, mobile phase B was AccQ·tagUltra eluent B, the flow rate was 0.7 mL/min, the injection volume was 1 μL, the column temperature was 55°C, the sample temperature was 15°C, the detection wavelength was 260 nm, the collection speed was 20 points/s, the time constant was 0.1 s, and the running time was 10 min.…”

“…In addition, the dynamics of the digestion of diets can be reflected to some extent by measuring the FAA concentrations in the in vitro residue at various time points [ 12 ]. On the basis of such studies, we have shown that CAS releases its AA faster than soybean meal (SBM) [ 6 ], and SBM releases its AA faster than corn gluten meal (CGM) [ 13 ]. In the present study, CAS or CGM were included in six diets at two kinds of CP levels (normal or low), and we aimed to i) determine their AA release dynamics in vitro , and ii) identify the relationship between the dynamics of AA release and nitrogen deposition in piglets consuming the diets by measuring their growth performance, blood biochemical indices, nitrogen balance, and protein expression of mediators of muscle synthesis and degradation.…”