Estimation of liveweight from chest circumference in double purpose crossbred calves during growth as a function of sex and racial group in the Maracaibo Lake basin

Resumo

With the objective of estimating live weight (LW) as a function of racial group and sex and calculating its relationship to chest circumference (CC) in growing crossbred double purpose calves under tropical conditions, 589 measurements were taken of animals in three herds distributed in the Maracaibo Lake basin and grouped by predominant race (indicus or Taurus) and sex. General analysis of the data yielded a correlation between LW and CC (P <0.001) with R2 = 0.96. The corresponding exponential (quadratic) general regression equation was LW = 115.10 + (-2.83 × CC) + (0.03 × CC2); LW in kg and CC in cm. Sex had a highly significant effect (P<0.001) on both LW and CC, but the racial group did not. According to these results, CC is a good indicator of LW in double purpose cattle during growth. The data were used to prepare a table presenting the variations of LW and CC, which can be used on farms not possessing a weight scale to estimate LW changes in the animals.