Prediction of Mature Weight and Maturing Rate from Body Measurements Taken on Angus and Charolais Calves at Birth11Published with the approval of the director of the Arkansas Agricultural Experiment Station, manuscript no. 00047.

Abstract

<h2>Abstract</h2> The objective of this study was to use body measurements taken at birth to predict mature weight (MW) and maturing rate (MR) of mature cows. Measurements for length of rear leg from hook to dewclaw (LL), circumference of forearm (FA), heart girth circumference, body length from point of shoulder to pin bone (BL), width at loin (WL), width at hip, and depth at chest (DC) were taken within 24h of birth on 131 purebred female Angus calves and 39 purebred Charolais female calves in 1992, 1993, and 1994. Fifty-four Angus and 20 Charolais cavles were available for estimates of MW and MR. Stepwise regression determined which traits would be significant predictors of MW and MR. Early BW or ADG (for various intervals up to 1yr of age) were also included in some models. Stepwise regression, including the seven body measurements, resulted in the following equations: MW=−230.12 + 22.54 (LL) +16.38 (FA) + 1.12 (BL) + 30.61 (WL) − 21.66 (DC) and MR=0.10018 − 0.00038 (BL). The R² values were 0.46 and 0.29, respectively. Including early BW or ADG in models for MW did not result in higher R² values, although models with fewer traits included were obtained. Results of this study indicate that body measurements taken at birth may be useful in predicting MW and MR of cows.