Prediction of standardised ileal crude protein and amino acid digestibility in legume seeds for pigs by in vitro analysis.

Publication Type

Contribution to conference

Authors

Jezierny D., Eklund M. and Mosenthin R.

Year of publication

2008

Published in

Tagungsband Schweine- und Geflügelernährung

Editor

K. Eder

Pubisher

Universitätsdruckerei , Halle (Saale)

Band/Volume

10./

Series/labeling

Schweine- und Geflügelernährung

ISBN / ISSN / eISSN

ISBN 13: 978-3-86829-075-2

Page (from - to)

107-109

Conference location

Halle (Saale)

Conference date

18.11.2008

Keywords

amino acid digestibility, crude protein, ileal amino acid, legume seeds, pig nutrition

Introduction: In 2005, the German Society of Nutrition Physiology (GfE) introduced officially the concept of standardised ileal digestibilities (SID) of crude protein (CP) and amino acids (AA) as basis for the protein evaluation of feedstuffs for pigs. Digestibility coefficients for CP and AA, determined in a variety of feedstuffs, were summarised in feed tables issued by the GfE (2005). These data are based on digestibility experiments carried out with growing pigs. However, these in vivo trials are time consuming, labour intensive and expensive and, in addition, require the use of surgically modified pigs for collection of ileal digesta. Hence, there is a need for more simple, rapid and cheaper in vitro methods to be used for routine measurements of CP and AA digestibility in feedstuffs for pigs. Several in vitro methods, simulating the digestive processes occurring in the digestive tract have been developed to estimate the digestibility of nutrients in feedstuffs for monogastric animals as reviewed by Boisen and Eggum (1991). In the present study, SID of CP and AA in different grain legumes including faba beans, peas and lupins were determined under in vivo conditions with growing pigs according to the guidelines of the GfE (2005). Simultaneously, in vitro SID values were determined according to the procedures by Boisen and Fernandez (1995) and Boisen (2007). Linear relationships between SID values determined in vitro and SID values based on in vivo experiments were established.Conclusions: lt can be concluded that several factors may affect the accuracy of the prediction of SID values based on in vitro measurements. The results of the present study indicate that a low variability both in the chemical composition of grain legumes and the corresponding in vivo digestibility values may limit the use of in vitro analysis for predicting SID values for CP and AA in legume seeds.Summary: The objective of this study with growing pigs was to evaluate standardised ileal digestibility (SID) of CP and AA in grain legumes, determined both in vitro and in vivo. Six different cultivars of faba beans or peas and 5 different cultivars of lupins were used. In vivo studies were carried out with growing pigs fitted with simple T-cannulas at the distal Ileum, whereas in vitro digestibility of CP and AA in legume seeds was determined by means of the two-step enzymatic method described by Boisen and Fernandez (1995). The values obtained were used to calculate in vitro SID of CP and AA as described by Boisen (2007). Calculated in vitro SID values were generally higher than measured SID values in vivo. Within legume seed species, linear relationship between calculated and measured SID values was low, probably due to the limited sample size and the low variability both in the chemical composition and in the in vivo SID values within the legume seed species. Covariance analysis results in a strong linear relationship between calculated and measured SID of CP and AA in all 17 cultivars of the legume seeds.