Factores del animal y el manejo predestete que afectan la edad al primer parto en hatos de lechería especializada de Costa Rica
Fecha
2019
Autores
Castillo Badilla, Gloriana
Vargas Leitón, Bernardo
Hueckmann Voss, Frank
ROMERO-ZUÑIGA, JUAN JOSÉ
Título de la revista
ISSN de la revista
Título del volumen
Editor
Agronomía Costarricense
Resumen
La edad al primer parto (EPP) corresponde a uno de los parámetros más importantes para
medir la eficiencia productiva de los bovinos,
y a su vez, influye en el rendimiento reproductivo y la composición de la leche. El objetivo
de este trabajo fue determinar el efecto de los
factores del animal y del ambiente, modificables
y no modificables, desde el nacimiento hasta el
destete sobre la edad al primer parto (EPP) en
hatos lecheros especializados de Costa Rica. Se
realizó un estudio cohorte retrospectivo para
cuantificar el efecto de estas variables sobre
la edad al primer parto (EPP), en el estudio se
incluyeron, un total de 2980 vacas de razas Jersey y Holstein que presentaron su primer parto
entre el 2013 y 2015, pertenecientes a 22 hatos
lecheros especializados, ubicados en diferentes
zonas ecológicas de Costa Rica, con datos en
el programa VAMPP Bovino. Se analizaron los datos mediante estadística descriptiva y un
modelo lineal generalizado. La EPP promedio,
para los animales en estudio, es 27,4 meses (±4,7).
Variables no modificables del individuo, como la
raza, presentaron efectos significativos en la EPP,
con valores de 30,1 (IC95%: 29,8-30,4) y 28,4
meses (IC95%: 28,1-28,8; p<0,001) en la raza
Holstein y Jersey, respectivamente. Por otra parte,
se determinó un efecto significativo de la variable
modificable de manejo (p<0,0001), en aquellas
fincas con protocolos de alta calidad de crianza
de terneras, se obtuvo una EPP de 27,6 meses
(IC95%: 27,2-28,0), significativamente menor a la
encontrada en las fincas con desarrollo pobre de
reemplazos (EPP: 30,2; IC95%: 29,8-30,6). Esta
tendencia se mantuvo, tanto en el análisis de la
variable de manejo de forma independiente como
en asociación con raza y finca. La eficiencia de
las técnicas de crianza se reflejaron en mejores
valores de EPP.
Animal effect and preweanig management on age at first calving in specialized dairy farms of Costa Rica. The age at first calving (AFC) correspond to one of the most important parameters to quantify the productive efficiency of bovines, because it influences the productive performance and milk composition. The aim of the study was to quantify the effect of the animal and environmental variables, modifiable and non- modifiable, from birth to weaning, on AFC in specialized dairy herds in Costa Rica. A cohort retrospective study was conducted, including a total of 2980 Jersey and Holstein cows with AFC in the period between 2013 and 2015, belonging to 22 specialized dairy herds located in different ecological zones of Costa Rica, with data in the Bovine VAMPP program. All data in the present research, was analyzed by descriptive analysis and a generalized linear model. The average AFC for the animals in the present study was 27.4 months (±4.7). Non- modifiable variables, like breed, had significant effect over AFC, with 30,1 (CI95%: 29.8-30.4) and 28.4 months (CI 95%: 28.1-28.8) for Holstein and Jersey respectively. Furthermore, the results showed a significant effect of management as a modifiable variable (p<0.0001) revealing that farms with high quality calf rearing protocols had AFC of 27.63 months (CI95%: 27.24-28.03), contrary to poor quality systems (AFC: 30.20; CI95%: 29.83-30.57). This tendency was consistent whether the management variable was included as independent in the model or associated to breed and herd factors, where high efficiency in calf rearing reflects into better values of AFC.
Animal effect and preweanig management on age at first calving in specialized dairy farms of Costa Rica. The age at first calving (AFC) correspond to one of the most important parameters to quantify the productive efficiency of bovines, because it influences the productive performance and milk composition. The aim of the study was to quantify the effect of the animal and environmental variables, modifiable and non- modifiable, from birth to weaning, on AFC in specialized dairy herds in Costa Rica. A cohort retrospective study was conducted, including a total of 2980 Jersey and Holstein cows with AFC in the period between 2013 and 2015, belonging to 22 specialized dairy herds located in different ecological zones of Costa Rica, with data in the Bovine VAMPP program. All data in the present research, was analyzed by descriptive analysis and a generalized linear model. The average AFC for the animals in the present study was 27.4 months (±4.7). Non- modifiable variables, like breed, had significant effect over AFC, with 30,1 (CI95%: 29.8-30.4) and 28.4 months (CI 95%: 28.1-28.8) for Holstein and Jersey respectively. Furthermore, the results showed a significant effect of management as a modifiable variable (p<0.0001) revealing that farms with high quality calf rearing protocols had AFC of 27.63 months (CI95%: 27.24-28.03), contrary to poor quality systems (AFC: 30.20; CI95%: 29.83-30.57). This tendency was consistent whether the management variable was included as independent in the model or associated to breed and herd factors, where high efficiency in calf rearing reflects into better values of AFC.
Descripción
Palabras clave
GANADO DE LECHE, COSTA RICA, MILK CATTLE, SPECIALIZED DAIRY, PRODUCCIÓN LECHERA, PRODUCTIVITY