Studies in grazing management. VI. The influence of free- and strip-grazing and of nitrogenous fertilizers on production from dairy cows

Abstract

1. An experiment with dairy cows is described in which the production per animal and per acre obtained in three methods of grazing management were compared during 2 years.(A) An intensive method. Strip-grazing daily on heavily fertilized grass sward.(B) A modified intensive method. Continuous, free-range grazing on a heavily fertilized grass sward.(C) An extensive method. Continuous, free-range grazing on a grass and clover sward receiving a basic application of phosphate and potash only.The intensively fertilized swards received a total of 212 lb. fertilizer nitrogen per acre, together with adequate amounts of phosphate and potash throughout the grazing season. No supplementary foods of concentrate type were fed to the cows during the experiment.2. For the comparison of production per animal 3 × 3 Latin-square experimental design, with twelve Ayrshire cows and periods of 3 weeks' duration, was used. Two separate trials were conducted during the grazing season of 1955 and a third trial during 1956.3. The different methods of grazing management and intensive use of fertilizer had little influence on the milk yield and butterfat percentage of the milk of the cows.