Interaction of Soybean Varieties and Heat Treatments and Its Effect on Growth Performance and Nutrient Digestibility in Broiler Chickens

Abstract

As production of European soybeans is expected to grow, optimal processing conditions need to be ensured for small and heterogeneous batches of soybeans. The effect of different soybean varieties, as well as heat treatments, on the growth performance and nutrient digestibility in broiler chickens was investigated. Two varieties, regarded as heat stable and heat labile after preliminary experiments, were partially de-oiled and thermally processed at 110 °C for 20 min and 120 °C for 20 min. The resulting soybean cakes were integrated into a mash diet and subjected to a 36-day long feeding experiment. A total of 336 one-day-old broiler chickens were divided into 24 pens, resulting in 6 replicates per treatment. With application of the 110 °C treatment, analysis of soybean cakes showed that the commonly required reduction in trypsin inhibitor activity (TIA) was only reached with one soybean variety. The higher processing temperature of 120 °C ensured sufficient TIA reductions in both soybean varieties. Elevated TIA concentrations resulted in decreased growth performances (p < 0.05) of the chickens, whereas no negative effect from overheating on growth performance appeared. Total-tract nitrogen retention (p < 0.05) and pre-caecal digestibility of several amino acids (p < 0.10) decreased with higher processing temperatures but had no negative effects on growth performance. In conclusion, the results indicate that processing conditions adjusted to the different varieties are essential to ensure optimal product quality.

A new method for determining protein solubility index (PSI) based on extraction with 5 mM alkali hydroxide and its correlation with trypsin inhibitor activity in soybean products

“…Therefore, in food, feed and industrial applications, several simple indices, including NSI, PDI, PS‐KOH, and others, have been selectively measured for assessing both nutritional values and functional properties of protein products (Averina et al, 2021; Batal et al, 2000; Frikha et al, 2012; Jia et al, 2021; Parsons, 1996; Shen et al, 2021; van Eys & Ruiz, 2021; Wolf et al, 1971). In contrast, TIA is not commonly measured, even though it is the most reliable quality parameter (Frikha et al, 2012; Hemetsberger et al, 2021; McNaughton et al, 1981; Qin et al, 1996).…”

“…The method for measuring trypsin inhibitor activity (TIA) has been improved in simplicity, accuracy, and standardization (AOCS, 2021; Kakade et al, 1974; Liu, 2019). Although TIA is the most reliable index for protein quality and subsequent animal performance (Frikha et al, 2012; Hemetsberger et al, 2021; Liu & Ruiz, 2021; McNaughton et al, 1981; Qin et al, 1996), it has been more practical and popular to measure PDI, NSI, UA and/or PS‐KOH for soybeans and other protein products (Averina et al, 2021; Cho & Ryu, 2021; Hemetsberger et al, 2021; Ibáñez et al, 2020; Jia et al, 2021; Parsons, 1996; Ruiz et al, 2020; van Eys & Ruiz, 2021).…”

Effect of Two Soybean Varieties Treated with Different Heat Intensities on Ileal and Caecal Microbiota in Broiler Chickens

“…The observed differences in crude nutrient compositions between the diets arose from the different soybean varieties and exerted some potential influence on gut microbiota. A detailed description of diets on performance indices is given in Hemetsberger et al (2021). The starch, fat, fiber, and mineral contents of feedstuff are known for their ability to shift the microbial composition in the gastrointestinal tract [29][30][31][32].…”

“…The heat-labile variety caused an increase in two Peptostreptococcaceae, one Clostridiaceae and one Lactobacillaceae. A correlation analysis of selected parameters received from Hemetsberger et al (2021) with ASVs found in the ileal and cecal digesta is shown in Figures S1 and S2 in the Supplementary Materials. Used phenotypical parameters were apparent ileal crude protein and amino acid digestibility, nitrogen retention, apparent total tract starch digestibility, weight gain and feed efficiency.…”

“…Selected characteristics of the soybean cake and diets of starter, grower and finisher phase. For a detailed description of diets, seeHemetsberger et al (2021) [19].…”