Technological processes of feed manufacturing affect protein endogenous losses and amino acid availability for body protein deposition in pigs

• Published in: Animal feed science and technology Vol. 113; no. 1; pp. 141 - 156
• Main Authors: Lahaye, Ludovic, Ganier, Philippe, Thibault, Jean-Noël, Sève, Bernard
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 2004; Elsevier
• Subjects: Agricultural sciences; amino acids; Animal production studies; Animal productions; Biological and medical sciences; dietary protein; digestibility; digestible energy; digestible protein; Endogenous losses; extrusion; Feed and pet food industries; feed processing; Food industries; Fundamental and applied biological sciences. Psychology; grinding; ileum; Life Sciences; mashing; nitrogen balance; nutrient availability; Nutrient ileal digestibility; Particle size; pelleted feeds; Pelleting; pellets; Pigs; protein deposition; protein intake; protein value; sunflower meal; swine; swine feeding; Technological treatments; Terrestrial animal productions; Vertebrates; wheat; Pigs; Particle size; Technological treatments; Nutrient ileal digestibility; Endogenous losses; Pelleting; Availability; Farming animal; Protein; Pig; Vertebrata; Meat animals; Mammalia; Endogenous; Treatment; Manufacturing process; Nutrient; Artiodactyla; Ungulata; Feed; Digestibility; ALIMENT POUR ANIMAUX; METABOLISME DES PROTEINES
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/j.anifeedsci.2003.07.005

In the pig, dietary protein value depends on the availability of amino acids (AA), usually estimated by way of ileal digestibility measurement. However, AA availability for body protein deposition is influenced by endogenous digestive losses specifically induced by feed components. The purpose of the experiment was to assess the impact of some feed manufacturing processes on AA ileal endogenous losses and their resulting availability for growth. Four technological treatments were applied to a wheat–sunflower meal mix and compared in vivo according to a 4×4 Latin square design. These treatments were two grinding conditions, leading to different particle sizes (1000 and 500
μm), and two pelleting processes, “regular” and “high-flow extrusion” (HFE), operated on the finest particle size only. Ileal specific endogenous losses and the coefficient of ileal real digestibility (CIRD) of AA were measured by way of the isotopic dilution method using
15
N
-leucine labelled pigs fitted with ileorectal anastomoses. The impact on nitrogen (N) and AA availability was assessed by N balance. Decreasing particle size from 1000 to 500
μm improved (
P<0.05) N (0.849 vs. 0.888) and AA (0.849 vs. 0.890 for valine) CIRD, as well as the ileal energy digestibility. In contrast to the regular pelleting process, the HFE process increased (
P<0.05) energy digestibility and improved (
P<0.05) N (0.792 and 0.824 for fine mash and HFE pelleting, respectively) and AA (0.795 vs. 0.840 for valine) coefficient of standardised digestibility (CISD). This effect of HFE was due to a significant decrease in N and AA endogenous losses (
P<0.05) rather than to a reduction in dietary protein ileal flow. However, due to the metabolic costs associated with the production of endogenous proteins, CISD variation could not accurately reflect the quantitative change in AA availability associated with the HFE process. On the basis of N balance data, we could estimate these costs and defined coefficients of ileal standardised availability of N (CISA) for body protein deposition. The improvements in N CISD and N CISA due to the HFE process were 4.0 and 12.6%, respectively.