Factors affecting age at first calving in purebred Jersey cows of specialized dairy farms in Costa Rica
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| Auteurs: | , , , |
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| Format: | artículo original |
| Statut: | Versión publicada |
| Date de publication: | 2014 |
| Description: | A retrospective study was performed on 28,367 purebred Jersey cows of specializeddairy farms from different ecological areas of Costa Rica, during the period between 2000 and 2010, to evaluate the effect of the place, time, and animal variables on age at first calving (AFC).The variables included were ecological zone, calving season, year of parturition, inbreeding index, number of lactations of the dam, and parturition type. The study included the data recorded in the VAMPP Bovino 3.0 software from the Regional Information Technologies Center for the Sustainable Animal Production, from the School of Veterinary Medicine at Universidad Nacional of Costa Rica. Data was analyzed in two phases: 1) descriptive statistics, 2) for each independent variable the mean of the AFC was calculated to each stratum, which was compared using 95% confidence intervals. Average AFC for the studied population was 29.35 months (SD: 6.77; 95% CI: 29.27 – 29.42). AFC had the tendency to increase over the years. This study demonstrated a plausible effect of the ecological zone, with a significant increase in the premontane moist forest (Bh-P), premontane rain forest (Bp-P), and premontane very humid forest (Bmh-P) (P<0,01). In addition, an effect was observed in the inbreeding index, parturition type, and calving season on the AFC value. The year of parturition and number of lactations of the dam variables did not affect the AFC. |
| Pays: | Portal de Revistas UNA |
| Institution: | Universidad Nacional de Costa Rica |
| Repositorio: | Portal de Revistas UNA |
| Langue: | Español |
| OAI Identifier: | oai:ojs.www.una.ac.cr:article/5958 |
| Accès en ligne: | https://www.revistas.una.ac.cr/index.php/veterinaria/article/view/5958 |
| Mots-clés: | dairy Jersey tropics information systems lechería trópico sistemas de información. |