Sintese da analise de ensaios de maximizacao da producao de leite de ovelha.
1987
Oliveira A.J. | Abreu J.V. | Martins V.M.
This article reports two series of experiments designed to specify physical and economic optima of the effect of different ratios of roughage to concentrate on the milk production of ewes. The basic experiment 1, at Mirandela, in the northeastern region, was conducted indoors over a period of 42 days during 2 years, while the experiment 2, at Oeiras (near Lisbon), in the central region, was conducted with the use of pasture over a period of 70 days, during 3 years. The experiments started about two months after parturition. Total milk yield was significantly affected by the concentrate for both the experiments, by the corn silage inputs for experiment 1, but not by the amount of hay for experiment 2. These conclusions are consistent for both the groups of sheep at each regional centre. All the equations presented had R2 values of 0,8 or greater. Diminishing total yields are predicted for silage in experiment at Mirandela. In this experiment 1 the concentrate effect was linear, but for experiment 2 the law of diminishing returns has been demonstrated for that input. There is a great difference in milk yields between native and breeding groups of sheep. At Mirandela, some intersubstition effect between concentrate and silage was remarked at lower levels. The response in milk yield to both the feed inputs appeared to be small in economical terms (author).
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