Auteur: Trindade H.
Jaar van uitgifte: 2015
Milk production is responsible for about 11% of global agricultural output in Portugal. Two regions, which together represent less than 10% of the land area of the country, contribute to 80% of Portuguese milk production: the Azores islands and the Northwest (NW) mainland area. The two systems are strongly specialized on milk production, but differ in terms of land use and intensity of inputs applied. The Azores dairy farming system houses 33% of national dairy livestock and is responsible for 30% of the annual 1,900,000 Mg Portuguese milk production. In this system, four-fifths of the surface area of dairy farms are occupied by permanent grasslands which are grazed all year round. Grazing is complemented by maize and ryegrass silage obtained from the remaining one-fifth of the farmland area. The more intensive NW dairy system is based on a double-cropping forage system (zero-grazing) that uses maize as a summer crop and Italian (annual) ryegrass as a cover crop in winter. This region is responsible for more than 50% of national milk production and holds 45% of national total of dairy cows. The high silage yielding potential and the annual use of up to 3.5 Mg concentrate feed per dairy cow allow animal stocking rates of 4-7 LSU ha‑1. This farming system may generate large N losses, particularly by nitrate leaching. Environmental issues currently play an important role driving changes and adaptation measures to improve system sustainability to comply with legal regulations. These modifications are being accompanied by very fast changes in farm structural characteristics; between 1993/1994 and 2009/2010 the number of dairy holdings has been reduced by more than 85% and the number of cows per farm has increased proportionally. The main problems affecting the Portuguese dairy sector at present are evaluated and possible solutions are suggested to face the upcoming challenges.