MILK AND PASTURES AT THE FRONTIER - THE CASE OF THE PERUVIAN FOREST MARGINS

The use of tropical grass-legume mixtures containing the grasses Brach iaria decumbens or Andropogon gayanus associated with a mixture of sev eral herbaceous legumes was tested on farms in the rainforest area of Pucallpa, Peru. Pastures were established by farmers using manual labo ur and without fertilizer in previously deforested areas covered with secondary growth. The pastures, together with their grass-alone contro l, were incorporated by farmers into the normal paddock rotation, and were grazed by dual-purpose cattle of mixed breeding. Cows were milked once daily by hand and with their calves at foot. Following a trainin g period, farmers kept records of milk yields. Frequent and unannounce d visits at milking time by the research team were used to verify milk yields and to annotate events such as calving, drying out, sales and others. Across farms and years, grass-legume mixtures significantly ou tyielded grass-alone pastures by 9%. Milk yields on the mixed pastures were examined further by stepwise regression. A positive and signific ant effect of the proportion of crossbred cows in the herd was establi shed, whereas soil quality (evaluated by the percentage of aluminium s aturation) had a negative impact on milk yields. Two of the farms, whi ch for different circumstances had poorer than average animal and past ure management, also had a significantly negative effect on milk yield . The interactions between animal and pasture management, and regional infrastructure are discussed. It is concluded that grass-legume mixtu res increased milk yields on farms. Nevertheless, it is also hypothesi zed that they may have a more restricted niche than anticipated and th at their adoption may be highly sensitive to the overall economic cont ext of the region.