info:eu-repo/semantics/article
Impacto de factores de manejo sobre la concepción en vaquillonas lecheras
Impact of management factors on days to conception in dairy heifers
Fecha
2020-06Registro en:
Vera, Milba Marina; Piccardi, Mónica Belén; Maciel, Martin; Franco, Liliana; Mezzadra, Carlos Alberto; et al.; Impacto de factores de manejo sobre la concepción en vaquillonas lecheras; Universidad Nacional de Córdoba; AgriScientia; 37; 1; 6-2020; 33-40
1668-298X
CONICET Digital
CONICET
Autor
Vera, Milba Marina
Piccardi, Mónica Belén
Maciel, Martin
Franco, Liliana
Mezzadra, Carlos Alberto
Balzarini, Monica Graciela
Resumen
Increasing the number of pregnant heifers per time unit improves reproductive efficiency in dairy herds. The objective of this work was to analyze the effect of management factors on conception. Reproductive events of 2532 heifers throughout 37 years were analyzed adjusting proportional risk models. The interval from the first service to conception (IPSC) was defined as the days passed from the start of the service period (IPS) to conception. The observation period per animal was 90 days. Models adjusted for IPSC include effects of age at the start of the service period (IPS), year, number and season of services, conception rate of bulls, and year-to-season interaction with services. The Weibull model adjusts the IPSC variation pattern. Conception was lower in heifers under 18 months, in the 2nd and 3rd service, and when bulls with less conception rate were used. Conception was higher in fall services by 1.17 times compared to spring services. Identifying management factors affecting days to conception in heifers allows developing strategies to improve reproductive efficiency in dairy herds.