Effect of Cereals and Legumes Processing on In Situ Rumen Protein Degradability: A Review

Abstract

The determination of the ruminal degradability rate of feeds, mainly starch and crude protein, is one of the most common methods to evaluate the nutritional value of ruminant feed. The protein requirements for ruminants are met from microbial protein and undegraded dietary protein digested in the small intestine. In order to reach maximum productivity, high-quality proteins are needed, and the requirement for undegraded dietary protein increases with the performance of the animal. This protein can be supplied by reducing the ruminal degradation to increase the amount of protein digested post-rumen, but the form in which a feed is administered influences degradability, and grain processing, especially, is a common practice to improve feed efficiency. Despite these aspects, studies on the effects of feed processing methods on protein degradability are limited, even though more and more ruminants are fed with processed feeds. For these reasons, this review investigated the protein degradability of different processed cereals and legumes in ruminants based on the analysis of available literature in order to take stock of the state of the art on this topic. Results showed that: First, the majority of the papers are focused on the energy aspects mainly due to carbohydrate-rich feeds; second, the majority of the studies in the literature are quite old, probably because the changes occurred in the animal testing legislation that made in vivo studies more and more difficult in the last 20 years; third, as a consequence, the few data available in recent years concern in vitro experiments; fourth, we found a high variability of the experimental conditions thus affecting protein degradability and making it quite difficult to compare the different results.

The Characterization of Pastures by Grazing Cycle and Evaluation of Supplementation with Agro-Industry Co-Products on the Performance of Buffaloes in the Humid Tropics

“…As the nutritional value of a feed does not depend exclusively on its nutrient content but also on the extent of ruminal degradation, it was observed that the sum of the digestible fractions (B1, B2, and B3) was greater in the coconut cakes (88%) and palm kernel cake (81.11) than in corn (64.45%) and soy (76.64), the conventional ingredients. The values found are compatible with other works, where the protein degraded in the rumen is 75–80% for soybeans and from 52 to 65% for corn [ 22 , 35 , 36 , 37 ]. However, there is also a comment on digestible protein’s amino acid composition and the investigation’s importance [ 37 , 38 ].…”

Nutrición animal: Texto de formación universitaria

“…La tasa de degradabilidad ruminal de alimentos, principalmente almidón y proteína, es uno de los métodos más comunes para evaluar el valor nutricional de los alimentos para rumiantes. Los rumiantes satisfacen sus requerimientos de proteínas con la proteína microbiana y la proteína no degradada en rumen (RUP) (Iommelli et al, 2022). La proteína degradada en rumen (RDP) se mide mediante la degradabilidad in situ con la técnica de la bolsa de nylon (Mehrez & Ørskov, 1977); (Ørskov & McDonald, 1979).…”

Comparison of Cassava Chips and Winged Bean Tubers with Various Starch Modifications on Chemical Composition, the Kinetics of Gas, Ruminal Degradation, and Ruminal Fermentation Characteristics Using an In Situ Nylon Bag and an In Vitro Gas Production Technique

“…Starch changes structurally and gelatinizes when heated in the presence of water. Its crystal structure also disintegrates, and its solubility and rheological properties are altered [39]. When combined with modification methods for starches, the difference in particle size, fiber content, pelletizing, extruding, pressure toasting, and other feed production techniques may significantly alter how starch in compound feeds breaks down in the rumen [40].…”

“…LA treatment has the ability to slow the enzymatic action of amylases in grains [42]. Moreover, Deckardt et al [39] demonstrated that, compared to dry-rolled barley, the gas volume was reduced early on, and the gas production constant rate increased after 24 h of steeping barley in water containing 7.5 g of LA.…”

“…Treatment with LA impacts starch degradation rates. This probably has to do with the fact that LA causes linearization of the branching amylopectin molecule [39], which makes amylopectin more like amylose and operates as a barrier to enzymatic digestion. Additionally, restricting enzymatic attack is a potential interaction between LA and gluten [9].…”