Genetic parameters of growth in a dairy goat herd under semi-intensive management in tropical environment
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| Autoři: | , , |
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| Médium: | artículo original |
| Stav: | Versión publicada |
| Datum vydání: | 2026 |
| Popis: | Introduction. The estimation of genetic parameters for growth in goats makes it possible to identify the contribution of additive direct and maternal effects at different stages of development, which is essential for designing more efficient selection strategies. Objective. To estimate growth genetic parameters in a dairy goat herd using random regression models. Materials and methods. The study was conducted at the experimental herd of the Universidad Nacional, Heredia, Costa Rica. A total of 6 127 body weight records from birth to 30 months of age were analyzed, these were collected between 2008 and 2024, from 388 females and 108 males of Saanen and Saanen×Toggenburg breeds. A mixed random regression model was fitted, including fixed effects: contemporary group, breed type, sex, parity, type of birth, and age; and random effects: direct additive genetic (h²d), maternal genetic (h²m), and permanent environmental (ap) effects, modeled using Legendre polynomials. Results. The value of h²d ranged from 0,01 (month 2, SE 0,01) to 0,17 (month 11, SE 0,08), the h²m ranged from 0,02 (month 2, SE 0,01) to 0,25 (month 1, SE 0,07), and the pe value increased progressively from 0,03 (month 1, SE 0,20) to 0.67 (month 30, SE 0,08). Genetic correlations (direct and maternal) and permanent environmental correlations were mostly positive and of moderate magnitude (>0.60), with higher values (>0.80) between adjacent ages. Direct breeding values for body weight ranged from −2,33 and 1,80 kg (month 3) and from −3,90 to 3,20 kg (month 12). Conclusions. The use of random regression models allowed the estimation of genetic parameters for growth while accounting for both animal and maternal effects at different stages. This approach facilitates more accurate selection of replacements and guides breeding strategies to obtain more productive and efficient animals. |
| Země: | Portal de Revistas UCR |
| Instituce: | Universidad de Costa Rica |
| Repositorio: | Portal de Revistas UCR |
| Jazyk: | Español |
| OAI Identifier: | oai:portal.revistas.ucr.ac.cr:article/2365 |
| On-line přístup: | https://revistas.ucr.ac.cr/index.php/ragromeso/article/view/2365 |
| Klíčové slovo: | peso corporal heredabilidad regresión aleatoria valor de cría body weight heritability random regression breeding value |