Growth evaluation of crossbred heifers raised under tropical conditions

• Autor(a) principal: Reis, Helena de Souza
• Data de Publicação: 2020
• Outros Autores: Castro, Caroline Medeiros, Silva, Ana Caroline Ramos Teles, Sousa, Thais Gomes Araújo, Moura, André Morais, Silva, Alex Lopes
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Engenharia na Agricultura
• Texto Completo: https://periodicos.ufv.br/reveng/article/view/11558
• topic: Breeding; Performance; Raising; insemination; growth; resaing

The objective of this study was to evaluate growth and body development of crossbred Holstein×Gyr calves and heifers raised in tropical conditions. Thirty-two crossbred heifers (Holstein×Gyr) aged between 1 and 1314 days were used. For assessing the animals’ body weight, the heifers were weighed once a week with a chest tape for weighing cattle, using the specification for medium breeds recorded on the tape itself. The experiment was conducted in a completely randomized design. Body weight data were analyzed using linear regression as a function of age, using the R software. We could observe that animals less than 200 days old had a performance estimate of approximately 0.517 kg day-1, while after at 200 days of life, the estimated weight gain was 0.237 kg day-1. Heifers had a higher growth rate before 200 days of age than after this age, which can affect the age at the first calving of the herd. Thus, as the age for the first breeding is linked to the weight of the live animals, the delay in the growth of the calves becomes detrimental to the breeding.