-Study of a subhumid method of straw processing with urea. We tested a subhumid processing method which reduces water content by 50% without the contribution of exogenous urease sources. The principle consisted in applying a 7% urea solution to one out of two layers of straw at a 40% humidity level, the last upper layer being systematically watered. The stack was then sealed as for classic ammoniation. At the same time, a classic treatment (also with 7% urea) was performed. At the end of the treatment which lasted for 75 days during the summer, four straw-based diets were evaluated: untreated straw (NT), classically treated straw (UC), non-damped straw (ULNH) and damped straw (ULH). Intake and organic matter digestibility were measured in rams (6 per diet) fed on straw supplemented daily with 200 g concentrate. After processing, the nitrogenous matter content increased from 5.8% (NT) to 11.0, 12.6, and 16.1% for ULNH, UC, and ULH, respectively, whereas the dry matter intake of pure straw was 47.5, 52.7, 54.1 against 59.7 g . kg -1. PV -0.75 for NT, UC, ULH, and ULNH, respectively. Organic matter digestibility was higher for ULNH (59.4%) than for ULH (56.3%), UC (51.1%) and NT (46.0%). The amount of digestible organic matter intake was 23% higher for straw derived from the subhumid treatment than that resulting from the classical treatment. urea / subhumid-treated straw / ingestibility / digestibilityRésumé -Nous avons testé un procédé qui réduit de 50 % le volume d'eau recommandé pour le traitement des pailles à l'urée sans apport de sources d'uréase. Le principe consiste à arroser avec une solution de 7 % d'urée un lit de paille sur deux à 40 % d'humidité ; le premier lit de paille n'étant pas arrosé, et le dernier lit supérieur étant obligatoirement arrosé. L'opération achevée, la meule est fermée comme pour un traitement classique à l'ammoniac. À la fin du traitement qui a duré 76 jours (en été), quatre lots de paille ont été constitués : paille non traitée (NT), traitée classiquement (UC), non humidifiée (ULNH) et humidifiée (ULH). Nous avons mesuré chez des ovins pour chacun des 4 lots de paille distribuée avec 200 g de concentré, la quantité de matière sèche ingérée (MSI), les Ann. Zootech. 49 (2000)
-Organic matter degradation (OMD) was studied with the techniques of in situ degradation and in vitro gas production (gas test) on 16 straws (TS) treated under different conditions of ammonia concentration (3 and 5%), duration (15, 30, 45 and 75 days) and temperature (15 and 35 o C). Gas production (GP) and OMD were measured at 2, 4, 8, 16, 24 and 48 h. The results showed that after treatment, compared with the untreated straw (US), the OMD at 48 h, GP at 48 h and organic matter theoretical digestibility (OMTD) increased by 31, 25 and 19% (P < 0.01). Among the treatment factors, temperature was mainly involved in the increase in OMD, GP and OMTD. The correlations established between OMD and GP at every kinetic point, and between OMTD and GP at every kinetic point were low. They were high only during the first 24 h of the GP incubation, particularly between OMTD and GP at 8 h. This does not allow the utilisation of the GP method to predict the OMD in situ, but GP at 8 h can be used for a rapid classification of the straws.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.