Adaptation of Some Grass Species to Grazing

To examine the grazing behaviour of some grass species, 2 linked trials were set up in Lusignan (France), Dry matter yields of 10 species were recorded by frequent mechanical cuts (every 15 days) and compared with the ability to feed sheep under continuous grazing management. The dry matter yield of the genotypes ranged from 5600 to 8600 kg DM/ha and the grazing yield from 86 to 183 days x animal. The well-known species, such as Bromus siIchensis L., 8. caIhar1ic11s L. and Dactylis glomerata L. usually used in farms allowed high dry matter and grazing yields, but some secondary species or turf-type cultlvars such as Aleopectmus pratensis L. or FesI11ca rubra L, seemed to be interesting for their ability to feed sheep

Textures, water content and degassing of silicic andesites from recent plinian and dome-forming eruptions at Mount Pelee volcano (Martinique, Lesser Antilles arc

Previous petrological and phase-equilibrium experimental studies on recent silicic andesites from Mount Pelée volcano have evidenced comparable pre-eruptive conditions for plinian and dome-forming (pelean herein) eruptions, implying that differences in eruptive style must be primarily controlled by differences in degassing behaviour of the Mount Pelée magmas during eruption. To further investigate the degassing conditions of plinian and pelean magmas of Mount Pelée, we study here the most recent Mount Pelée's products (P1 at 650 years B.P., 1902, and 1929 eruptions, which cover a range of plinian and pelean lithologies) for bulk-rock vesicularities, glass water contents (glass inclusions in phenocrysts and matrix glasses) and microtextures. Water contents of glass inclusions are scattered in the plinian pumices but on average compare with the experimentally-deduced pre-eruptive melt water content (i.e., 5.3– 6.3 wt.%), whereas they are much lower in the dominant pelean lithologies (crystalline, poorly vesicular lithics and dome samples). This indicates that the glass inclusions of the pelean products have undergone strong leakage and do not represent pre-eruptive water contents. The water content of the pyroclast matrix glasses are thought to closely represent th

Effects of Growth Stage and Grain Glucosinolates Content on Rapeseed Forage Feeding Value

Castrated sheep on maintenance were fed in 2 consecutive years for 4 weeks with fresh summer-sowri rape (Brassica napus) forage. In spite of the energetic value at flowering stage (both by ill vitro or in vivo method) being lower than at the vegetative stage, it appeared to be quite good in comparison with the energetic value of grasses or legumes at flowering stage. We did not observe any difference linked with seed glucosinolates content