Dairy farmers regularly make decisions about the future of either individual cows or groups of cows for all sorts of reasons.

Whilst sometimes the need for a decision will be entirely predictable (for example, following a pregnancy test), at other times, the decision can crop up unexpectedly (for example, after a repeat case of clinical mastitis).

Whilst the need to cull a cow sometimes is sometimes obvious because there is little alternative, often the farmer will need to weigh up the “pros” and “cons” of either keeping or culling an individual cow.

A cow’s mastitis status is just one of the many factors that is likely to be considered.

Typically farmers will weigh up a cow’s age, production, genetic merit, pregnancy status, temperament and the presence of any other disease or problem, as well as the cow’s mastitis status.

Fortunately, farmers have a number of reference points to help deal with these decisions.

Countdown Downunder has given clear guidelines of thresholds at which cows may be considered for culling.

The fundamental principle of Countdown’ s recommendations lies in the concept that persistently infected or non-responsive cows may need to be culled due to the unlikelihood of a cure for the infection, and also the potential that the particular cow has to act as a source of infection for the rest of the herd.

The Countdown Farm Guideline 15 gives us two criteria to work with –

Guideline 15.1 tells us to “Consider culling any cow when you find her third clinical case for this lactation.”, and Guideline 15.2 tells us to “Consider culling cows with high cell counts in two consecutive lactations, despite treatment with Dry Cow Treatment in the dry period between.”

Whilst both criteria require records to be available, the second criteria clearly requires individual cow cell counts to be available. Farms that herd record and have cell counts available will be in a much better position to make these decisions.

Some of the other factors that will be considered in a culling decision also have sources of information and criteria to apply.

As an example, the InCalf project has produced the InCalf Book which includes a section that outlines and discusses the factors associated with keeping or culling late calving cows and also potentially less fertile “carry-over” cows.

Again, the ability to apply the InCalf resources will be enhanced by the availability of the best information – in this case, pregnancy testing results will enhance the decision making process.

The more information that is available on which to base a decision, the easier the decision will be, and the likelihood of making the best decision will be enhanced.

Retaining on-farm records in an easily accessible location will make the whole process quicker and easier – whether that is a computer or a record book/shed sheet.

In summary, because there are often many factors that contribute to a culling decision, the quality of the decisions will be enhanced by the quality of the information and records available, and the use of appropriate guidelines.