02107naa a2200301 a 450000100080000000500110000800800410001910000230006024501170008326000090020052012420020965000130145165000160146465000110148065000140149165000090150565300110151465300100152565300120153565300080154765300120155565300180156765300200158565300190160570000180162470000170164277301460165918012582017-03-31 1999 bl --- 0-- u #d1 aABREU, U. G. P. de aEstimates of culling probability and expected productive life of brood cows in Pantanal of Mato Grosso (Brazil). c1999 aA herd of 1,200 brood cows in the Brazilian Pantanal were monitored from 1994 to 1998 in order to analyse herd management and composition in terms of age and cull rate providing a more intensive monitoring strategy than traditionally is followed. The probability of culling was verified using a logit procedure. Time (order of monitoring session) and age of brood cow were significant in these estimates (P<0.01). The cull probabilities by age from 2 to 21 year, were: 1.02%, 1.26%, 1.56%, 1.92%, 2.37%, 32.56% and 37.41%, respectively. From these estimates the expected productive life of the cows was calculated (in years): 12.40, 11.53, 10.68, 9.73, 9.04, 8.26, 7.51, 6.80, 6.10, 5.45, 4.83, 4.26, 3.72, 3.22, 2.75, 2.32, 1.91, 1.51, 1.09 and 0.63, respectively, with an average brood cow age of 13.29 years. The cull rate was 7.5% per year, yielding a total replacement of the herd every 13.3 years. Estimated cull rates under traditional management is about 4.6% (27.8 years for total herd replacement). These data provide the basis to simulate different cull strategies as a function of existing herd strucure and interactions with management practices, environmental variables (floods) and the economic efficiency of the system. aPantanal aprobability aBovino aSeleção aVaca aBovine aBrood aCalculo aCow aCulling aProbabilidade aProductive life aVida produtiva1 aMORAES, A. S.1 aSEIDL, A. F. tIn: SYMPOSIUM ON SYSTEMS APPROACHES FOR AGRICULTURAL DEVELOPMENT, 3., 1999, Lima. Abstracts... Lima: Participants Manual, 1999. nao paginado.