15 décembre 1987
auteur | co-auteur
En 1986, dans le Nord-Finistère, une étude a été réalisée sur 30 exploitations pratiquant le pâturage continu pour mesurer l'évolution de leurs performances par rapport à un groupe comparable d'exploitations où le pâturage était conduit en paddocks (dans les 2 cas: prairies à base de ray-grass anglais et fertilisation de 450 kg N / na en moyenne).L'évolution des résultats annuels sur 4 années et l'analyse des résultats mensuels corres¬pondants ne permettent de dégager qu'un seul facteur dissemblable: le taux butyreux, inférieur d'un point en pâturage continu. Tous les autres indicateurs techniques (rendement lait sans concentrés par hectare, moyenne économique, quantités de concentrés, chargement, taux protéïque, persistance ... ) sont identiques.La variabilité supérieure entre exploitations pratiquant le pâturage continu pourrait s'expliquer par des niveaux de technicité inégaux.
Intensive set-stocking was introduced in 1982 into North-Finistère, and more than one hundred farmers apply this technique presently.In 1986, a study of 30 such farms was made in order to compare the evolution of their results with those of a comparable group of farms where the paddock grazing system was used. In both cases, the swards consisted almost exclusively of Perennial Ryegrass, which received large applications of fertilizer nitrogen (450 kg N/hectare on average).The yearly results of farm management evolved in the same way in both groups during 4 years, especially as regards: milk yield per hectare without concentrates, economie average, amounts of concentrate distributed, stocking rates ... The performances of the herds under study were also comparable to those under the control of the milk gathering organization in the same districts. Only the butterfat content was lower under set stocking (by about 1 point).Apart from the butterfat contents, the monthly results were also quite similar (milk yields, production ascribed to the basic diet, protein contents, persistencies ... ).A more detailed analysis of the farms under set-stocking shows that there are large variations between farms as regards grazing performances, especially stocking rates; this could be explained by differences in technical know-how.
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