Optimization of forage area utilization in dairy cattle kept in the subtropical zone

Abstract

Model studies on optimal utilization of forage area for cow milk production in the subtropical zone were carried out. The linear programming method was used for calculations and initial programmes (models) on the basis of materials obtained in Israel and Turkey were made. In some cases data from professional literature were also applied. In 30 best solutions the annual milk production from 1 ha of forage area exceeded 16 000 kg (maximum value 16 137 kg), at the daily milk yield per cow ranging from 24 to 33 kg and animal number ranging from 1.6-2.2 structural cows per ha. The increase in daily milk yield of cows and in milk production per unit of forage area was accompanied by changes in structure of forage crops. In solutions with the lowest milk production most of the area was occupied by plants cultivated for green forage, hay and silage (Alexandrinum clover, maize for silage, Sudan grass). In solutions with higher levels of milk production their area decreased in favour of barley and maize grown for grain and straw, cotton for seeds used as feed, and lucerne. The elaborated models can be used, after slight modifications, for optimization of forage area utilization in other climatic zones, including the temperate zone.