Back Don’t keep milking poor performers

Date: 27 February 2017

Low producing cows use a much higher percentage of their total intake for maintenance than their higher producing counterparts. Getting rid of poor performers and obvious culls (empties and high cell count cows) early means there is more feed to put into the rest of the herd.

For a 400-cow farm, culling 40 cows will release around 600 kgDM per day, or an additional 1.7 kgDM per day for every cow remaining on the farm. If the culls are producing 1 kgMS/cow/day removing them from the farm will result in a decrease of 40 kgMS/day. However using the drymatter they were eating to feed the remainder of the herd better has the potential to lift their production by up to 80 kgMS/day. The result is a net production gain of up to 40 kgMS/day. Reducing cow numbers also reduces any associated animal health costs such as facial eczema prevention.

Feed supplement to keep cows in milk

Milking on can be quite lucrative especially at a $6.00/kgMS payout. Cows producing as little as 0.7 kgMS/cow/day, feeding maize silage (35 c/kgDM eaten, 10.8 MJME/kgDM) generates a return of more than $1.75 per cow per day. This translates to a return of more than $700/day for a 400-cow herd (Table 1).

Table 1: Economics of milking on rather than drying off cows


Assumptions: 1. Cows will be fed maintenance even if they are dried off. 2. Farm labour costs are fixed. 3. Post grazing pasture residuals have dropped to below 1500 kgDM/ha.  4. No extra capital will be required to run the system. 5. Protein is not limiting. 6. Other costs (feed-out, shed etc.) are 12 c/kgDM

Once a cow is dry, you get no milk till next season. Filling late summer to early autumn feed deficits and milking on will allow you to take advantage of any autumn pasture flush which further improves returns.

Watch Body Condition Score (BCS)

Achieving BCS targets of 5.5 for your 1st and 2nd calvers and 5.0 for the rest of the cows in the herd, is non-negotiable.  There is no better farm system feed than maize silage to enable you to do this because it will keep cows in milk while protecting body condition and pasture cover levels.

The first step is to condition score your herd. Enlisting the help of a qualified rural professional, or even neighbour or two, may give you a more accurate assessment. DairyNZ also has an excellent resource freely available to all farmers called "Condition Scoring Made Easy" that will help in this process.

DairyNZ recommendations1 include:

  • Give the first calvers more time dry than older cows.
    Young cows are still growing to reach their mature weight and often have lower intakes. Therefore, they are only able to put weight on slowly and require more time to get to target condition.

• Staggered dry-off based on BCS and time to calving.
In higher input systems, where dry cows are well fed on a mixture of pasture and supplement, cows that are BCS 4.5 or better only require 50-60 days dry; cows that are BCS 4.0 or worse need around 80-90 days dry.


 Careful and strategic management will ensure you make the most of the rest of the season. To learn more about autumn feeding maize silage, contact your local Pioneer representative.