Conservation et utilisation des spathes de mais par les ruminants. 1. Mise au point d'une technique de conservation et utilisation par les genisses (laitieres et a viande) en croissance, agees de un an, au cours de la periode hivernale

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Treatment of straw with urea. 1 : ureolysis in a low water medium

International audienc

Effects of elevated CO2 and cutting frequency on the productivity and herbage of a semi-natural grassland

International audienceMonoliths of a fertile, although N limited, C-3 grassland community were subjected (or not) to an atmospheric CO2 enrichment (600 mumol mol(-1)), owing to the Mini-FACE system from August 1998 to June 2001, at two contrasting cutting frequencies (3 and 6 cuts per year). The present study reports the effects of elevated CO2 on the above-ground productivity and on the herbage quality. Elevated CO2 did not affect the dry matter (DM) yield of the swards in 1999. In 2000, the second year, there was a positive CO2 effect (+26%) both on the DM and on the nitrogen yields (+30%). With the frequently cut monoliths, the DM of the legume component of the sward was strongly increased by elevated CO2. This effect became also significant in July 2000 for the low cutting frequency treatment. These results are in good agreement with the concept of an increased legume development and symbiotic N-2 fixation triggered by an increased ecosystem scale demand of N under elevated CO2. At a low cutting frequency, the DM of the forbs was strongly increased in elevated compared with ambient CO2. This increased development of the forbs apparently led to a competitive decline of the grasses. Therefore, the total DM yield response to CO2 was smaller at a low (+15%) compared with a high (+36%) cutting frequency in 2000. An increase in the water Soluble Sugar content of the bulk forage under elevated CO2 and a corresponding decline in cell wall contents (NDF) were observed. In June 1999, the decline in NDF was correlated with an increased in-vitro DM diaestibility. The forage quality was also indirectly affected by elevated CO2 through changes in leaf:stem ratio and in botanical composition. At a low cutting frequency, the increased forb content favoured the herbage quality because of a higher digestibility of the forb shoots and, indirectly, through the reduction in the mass of the grass sterns. These results emphasise the role of species dynamics for elevated CO2 impacts on semi-natural grassland productivity and herbage quality

Disparition des acides phenoliques de la paille de ble en fermenteur semi-continu; influence de l'acide p coumarique sur la degradation des glucides parietaux

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Preliminary observations of flavonoid glycosides from the vegetable coagulant Cynara L. in protected designation of origin cheeses

International audienc

Net energy value of non-starch polysaccharide isolates (sugarbeet fibre and commercial inulin) and their impact on nutrient digestive utilization in healthy human subjects

7 tables 2 graph.International audienc

Variabilité de la teneur des laits en constituants d'intérêt nutritionnel selon la nature des fourrages consommés par les vaches laitières

National audienc

Variabilité de la teneur des laits en constituants d'intérêt nutritionnel selon la nature des fourrages consommés par les vaches laitières

National audienc