Changes in European dairy policy will likely translate into significant on-farm management adjustments like more intensive grass-based production systems characterized by increased stocking rates.
Researchers in Ireland recently evaluated the impact of increased stocking densities on herd reproductive performance given this scenario. The results were published in the March 2012 Journal of Dairy Science.
They found that stocking rate and calving date (either around February 12 or around February 25) had no effect on pregnancy rates, immunological parameters, or health status, although a tendency was observed for more reproductive intervention as stocking rate increased.
The researchers conclude that although resulting in increased requirement for reproductive intervention, increased stocking rates are unlikely to have a harmful effect on pregnancy rates or health status of the Irish dairy herd. Furthermore, the presence of a strain of Holstein-Friesian by stocking rate interaction indicates that selection for a better conditioned New Zealand strain may be more appropriate for grass-based dairy systems with an increased stocking rate.
Source: Dairy Cattle Reproduction Council