Prediction of digestibility of organic matter and energy in the growing pig from an in vitro method

The method of Boisen and Fernandez [Boisen, S., Fernandez, J.A., 1997. Prediction of total tract digestibility of energy in feedstuffs and pig diets by in vitro analyses, Anim. Feed Sci. Technol. 68, 277–286] for measuring in vitro fecal digestibility of organic matter (OMdv) or in vitro digestible organic matter content (DOMv, g/kg) was used on 113 compound feeds (79 as mash and 34 as pellets) and 66 ingredients (as mash) whose digestibility of organic matter (OMd) and energy (Ed) and digestible energy content (DE, MJ/kg) had been measured in 60 kg growing pigs for all compound feeds and ingredients, and in adult sows for about 2/3 of the compound feeds (as mash); net energy (NE, MJ/kg) of these feeds were estimated from digestibility information. The repeatability and accuracy of the method were evaluated. Data obtained on compound feeds fed as mash were used to establish prediction equations of OMd, Ed, DE NE from OMdv or DOMv and chemical criteria. The levels of accuracy and repeatability of OMdv measurement were satisfactory and values for OMdv and OMd of mash compound feeds were very close and highly correlated (r= 0.91). Apart from OMdv, the best prediction equations of OMd or Ed included ash content and a cell wall criterion (ADF or crude fiber); for prediction of DE, fat content had also to be considered. The coefficient of variation of all equations was below 0.02. The equations allow a satisfactory prediction of OMd, Ed or DE of the 66 ingredients fed as mash. However, the equations established on data obtained on mash feeds underestimate the in Abbreviations: DM, dry matter; DE, digestible energy; NE, net energy; OM, organic matter; OMd, organic matter digestibility; Ed, energy digestibility; OMdv, in vitro organic matter digestibility; DOMv, in vitro digestible organic matter; OMdp, predicted OMd; Edp, predicted Ed; DEp, predicted DE content ∗ Corresponding author. Tel.: +33 223 48 50 49; fax: +33 223 48 50 80. E-mail address: [email protected] (J. Noblet). 0377-8401/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.anifeedsci.2006.07.008 212 J. Noblet, Y. Jaguelin-Peyraud / Animal Feed Science and Technology 134 (2007) 211–222 vivo nutritional value of pelleted feeds and are not applicable to prediction of energy value of feeds for adult pigs. © 2006 Elsevier B.V. All rights reserved.