Achieving high milk production performance at grass with minimal concentrate supplementation with spring-calving dairy cows: actual performance compared to simulated performance
Résumé
The aim of high-profitability grazing systems is to produce milk efficiency from grazed pasture. There
is very limited information available on the milk production capacity of dairy cows offered a grass-only
diet for the main part of her lactation. In this study, spring-calving dairy cows were managed to achieve
high milk production levels throughout the grazing season without supplementation. The calving date
of the herd was 12 April; the herd had access to grass as they calved and remained full-time at grass until
20 November. During this period the herd produced 5,513 kg milk, while receiving 130 kg concentrate
supplementation. The herbage mass offered was maintained at 1,490 kg dry matter ha‑1 (>3.5 cm) and
the herd grazed to 4.5 cm across the grazing season. The weekly milk production performance achieved
was then compared to the Herd Dynamic Milk model. The root mean square error (RMSE) and relative
predicted error (RPE) for milk yield (as expressed weekly across lactation) was 1.47% and 6.09%,
respectively, for body condition score the RMSE and RPE were 0.093% and 4.14% respectively. Offering
spring-calving cows high levels of high quality grass resulted in excellent animal performance, however,
this can be achieved with very good daily grazing management.
Domaines
Sciences du Vivant [q-bio]
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...