MODELING THE ECONOMICS OF ANIMAL HEALTH CONTROL PROGRAMS USING DYNAMIC-PROGRAMMING

A new application of an optimization tool, dynamic programming (DP), i s described to model the economics of animal health control programs. To demonstrate the value of this technique, a model is applied to dete rmine optimal net benefits of controlling East Coast fever (ECF) in Ma lawi Zebu cattle in the Lilongwe plateau. The objective function was t he present value of net benefits due to treatment, defined as mortalit y savings minus treatment costs. Mortality savings were based on decre ased mortality from ECF following treatment. Model constraints include d herd size, animal (herd) nutritional requirements, and program budge t. Treatment options were tank dipping in acaricide, and vaccination. Secondary data from a dipping trial of 1800 Malawi Zebu cattle conduct ed from 1991 to 1994 were used to determine probabilities of mortality . Total optimal net benefits of long-term treatment (25 years, i = 10% ) from vaccination (Malawi Kwacha (MK) 21 069) exceeded benefits for t reatment with chlorfenvinphos acaricide (MK15 203). (C) 1997 Published by Elsevier Science Ltd.