| Popis: |
Title of the paper: Prediction of the body weight of Simmental heifers using heart girth measurements The decision of the date of the first insemination of heifers is mainly based on the weight. In most of the dairy farm no scale exists, therefore a trial had been started to estimate a regression equation for the prediction of the body weight by the heart girth measurement. On seven farms the weight, heart girth and hip height of 324 heifers had been collected. The age of the heifers had been between 8 and 26 months. Additionally the results of heart girth and weight of 347 heifers out of 8 farms had been included. The analysis of the farm influence, adjusted by age, showed high significant effects in hip height, heart girth and weight. Heifers, grown up on farms with higher milk yield, had a larger size. For predicting the body weight of Simmental heifers using the heart girth measurement (BU) the following equation had been analyzed: ŶGEW = 137.6–2.647 * XBU + 0.024 * XBU2. The R2-value is 0.94. |
