Phenotypic correlations between linear traits and growth curves of Holstein calves

• DOI: https://doi.org/10.22533/at.ed.96624300419

• Palavras-chave: Curvas de crescimento; Monitoramento de rebanhos; Novilhas

• Keywords: Growth curve; Herd monitoring; Heifers

• Abstract: The selection of productive traits have great importance for the good performance of dairy farms. Strategies are developed with the aim of promoting the genetic improvement of the desired traits in future generations. The general objective of this study was to establish the growth curve of the Holstein breed, considering factors that contribute to precocity, especially in relation to body weight and withers height. Monthly measurements of body weight and withers height, as well as rump measurements, were carried out, enabling the monitoring of the development of Holstein calves in a dairy farm in São José dos Pinhais, Paraná. The results showed high and positive correlations (r) between the different measurements, as follows: (a) withers height x rump length: r = 0.91; (b) rump ileus width x body weight: r = 0.86; (c) rump ischium width x body weight: r = 0.96; (d) rump ileus width x rump ischium width: r = 0.84; (e) rump length x rump ileus width: r = 0.84 and (f) rump length x rump ischium width: r = 0.98. Average daily weight gain was highest in the first six months of age, followed by a slowdown due to pre-puberty behavioral factors. The importance of growth curves for breeding programs is emphasized, demonstrating the need for efficient management to optimize future reproductive performance. The correlation between body development and the anticipation of heat externalization in calves is relevant for reproductive management.