FEATURES OF THE GROWTH AND DEVELOPMENT OF THE HOLSTEIN HEIFERS
The growth and development
DOI:
https://doi.org/10.52269/TDG2541166Keywords:
replacement heifers, body weight, weight gain, measurements, indices, type of body conformationAbstract
The study was conducted on a purebred Holstein herd. The research objective was to investigate the productive characteristics of replacement heifers during growth and development, depending on their birth weight. The animals were divided into four groups: I – 41–45 kg, II – 36–40 kg, III – 31–35 kg, and IV – 25–30 kg. Evaluations were performed at birth and at 3, 6, 9, 12, 15, and 18 months of age.
The results showed that heifers in groups I, II, and III surpassed their peers in group IV in terms of body weight by 3.9–12.7% (8–27.8 kg). Higher birth weight contributed to more intensive growth in the early age periods (up to 6 months), indicating greater precocity (up to 90%). Average daily gains of heifers in groups I–III exceeded those of group IV by 79–64–9 g (14.8–12.3–2%). During later periods (6–18 months), growth rates were uneven, with alternating phases of accelerated and slower development. The data obtained confirm that birth weight is an important factor determining the subsequent growth and development of replacement heifers. The research results are useful for optimizing breeding work and improving the breeding value of animals.
