“…Thus a systematic approach to the identification and evaluation of constraints is required. Research /extension strategies such as 'farming systems research/ on-farm trials, participatory development, etc., have been developed with the aim of improving the effectiveness of research/extension work by researchers and farmers working in crop-based systems and little as yet has been done to apply a 'systems' approach to the evaluation of the research needs of livestock systems or the livestock component of mixed systems (Tripp and Woolley, 1990). At the Faculty of Veterinary Medicine and Animal Production of the Autonomous University of Yucatan (FMVZ-UADY) in Mexico it was decided to use a 'systems' approach to evaluate the problems existing in the regional animal production systems to derive research and teaching priorities for the faculty, and to monitor the use of improved animal production technology by farmers.…”