LAND UTILIZATION INOEX (LUI) The number of days during which crops occupy a given area of land during a year, divided by 365. LEY FA RMIN~, A ROTATION of arable crops requ.irin;g artificial .r improved pastures wuhi-h years or langer. annual cultivation and occupy the field for two LINEAR PROQGAMMQING A mathematical procedure that determines an optimal allocation of resources by maximizing or mini:z;ing an objective function subject to a set of specified constraints. The objective and constraint functions are linear. LIVESTOCK PATTERN The types and classes of animal run by the farmer over some period and the manner in which they are kept. LIVESTOCK SYSTEM, LIVESTOCK PRODUCTION SYSTEM A SUBSYSTEM within the FARMING SYSTEM concerned with the production if- a particular animal product (e.g. milk or power) and comprising all COMPNENTS required for such animal production, including the interactions among the animals, other farm and household enterprises, and the physical, biological and socioeconomic environment. LIVESTOCK SYSTEMS RESEARCH Research cr'ented to LIVESTOCK SYSTEMS. It is similar to CROPPING SYSTEMS RESEARCH but with procedures that reflect the inherent dif-erences between CROPPING and LIVESTOCK SYSTEMS e.g., fewer numbers oi animals than plants. PAGE 14