Possibilities and constraints for grazing in high output dairy systems
2015
Hennessy, David | Delaby, Luc | van den Pol-van Dasselaar, Agnes | Shalloo, Laurence
In temperate and oceanic regions, grazed grass is the lowest cost feed available for milk production. Inother regions, grazed grass is less important but can contribute to the diet of livestock. Within high outputsystems the interaction between the animal and sward is challenging for a host of reasons, includingintake and milk production potential, substitution, grass allowance, quality, etc., which often means thatgrass utilisation and quality are compromised. Adaptation of grazing management and implementationof a range of grazing strategies can provide possibilities to increase the proportion of grazed grass in thediet of dairy cows in high output systems. As Europe transitions to a non-milk quota situation, increasingscale, or herd size, will probably lead to a trend towards a reduction in grazing, and may lead to a loss ofthe benefits of grazing. Therefore, strategies are required to increase the level of grazed grass in the diet ofdairy cows on high output farms through the integration of grassland measurement and budgeting withineveryday grassland management practices. There is a growing body of literature describing the benefitsof grazing from an economic, environmental, animal welfare and overall social dimension. However,there are fewer reviews highlighting the constraints and difficulties to maintaining a high level of grassutilisation and good grazing performance in high output systems. The objective of this review is to presenta balanced overview of the possibilities and the constraints for grazing in dairy systems in the future.
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