The impact of calving system on milk yield and quality

Published 25 October 17

As part of our new approach on optimal dairy systems, we have looked at the impact different calving systems can have on milk yield and compositional quality. We have analysed the average results from farmers who self-assess themselves as being on a particular production system.

Farmers operating all year round calving systems have produced the highest yield per cow of the three systems, averaging 8,420 litres/cow over the last 3 years*. Farmers operating autumn block calving yielded 4.2% less per cow, and spring block calvers have seen average yields of 5,891 litres/cow, 30% lower than AYR. 

2017.10.26 systems yield

Although spring block calving herds have shown the lowest yields, they have performed best in terms of compositional quality, with higher average butterfat and protein levels than AYR and autumn block herds. Autumn block calving herds have also produced marginally higher milk solids than AYR. In terms of quantity of milk solids produced this slightly counteracts the reduction in yield, with spring block production 25.6% behind AYR production and autumn block production only 3.2% below AYR.

2017.10.26 systems composition

This analysis does not predict the impact for an individual farmer looking to change calving system, but does give an indication of the level of performance seen by farmers already operating each system.


* 2013-2016 - Promar data excluding Channel Island breeds