ICBF on culling: Which cows should go?

By Dr. Margaret Kelleher, ICBF

The continuing drought is causing serious problems for farmers. There is little sight of any immediate respite as limited/no rainfall continues.

As a result, farmers have been left with tight grass supplies and some have decided, as a last resort, to cull early in the season.

Under these unprecedented conditions, identifying those cows to remove becomes urgent.

However, culling productive animals will have serious knock-on effects to the herd profile and profitability.

Considering which cows to cull, the first cut may seem simple – sell empty cows. Problem cows, such as those with high SCC (somatic cell count) or lameness issues, would be the next logical step when reducing stocking levels.

However, the culling criteria becomes more complex when high producers, high genetic merit or young cows get shortlisted in this cut. What criteria should I work with?

For those dairy herds that operate spring-calving systems, that milk record and are members of HerdPlus, a culling tool is available to you at a touch of a button.

The culling tool is called C.O.W. (Cow’s Own Worth) and this online profile will rank your cows to highlight the animals that could be considered to sell, while keeping those that have the most profit potential for their remaining lifetime.

This is determined by factors such as: a more productive life remaining; better genetics; better survival potential; better health probabilities; and so on.

So, what do you need to do?

For many members, culling candidates will be ranked and identified as soon as you log into your HerdPlus account and select C.O.W. under the Profiles tab.

C.O.W. uses all the information available on your cows in your herd from most profitable to least.

Milk recording information is automatically fed into the C.O.W. system to rank cows. Calving dates as well as insemination/pregnancy diagnosis data are also used to rank cows.

Health events, genetic merit and the age of each cow are all considered when ranking the herd.

For example, C.O.W. takes into account that a first-calver is not at her mature ability for milk production, therefore you will not see all your first-calvers on the list for culling if you were to consider milk yield as your only culling criteria.

Given the time of year, the breeding season has closed for spring-calving herds, and breeding information is an essential element for accurate rankings of your cows to make culling decisions.

Herds will differ in their methods:
  • 100% AI by a technician: All serves will have automatically been accessed by C.O.W. and cows in the herd will be ranked accordingly based on expected calving dates for 2019. If cows are empty, it is best to mark these cows as empty through Herdplus so that they are considered for culling;
  • DIY AI: It will be important to get the serve data for your herd recorded through HerdPlus or other farm package software before July 31. After this date, C.O.W. will no longer be available as the ranking of your cows will be out-of-date. C.O.W. will rank cows on expected calving dates for next year – therefore date of last serve is required to accurately rank the herd. Alternatively, scanning information can be used to open the access to C.O.W profile;
  • Stock bulls: C.O.W. will be available up to July 31. After this date, C.O.W. can be accessed if empty cows are recorded. Additional information such as date bull served a cow will be beneficial as the cow will be ranked on expected calving date and therefore improves the accuracy of your C.O.W. rankings. Knowing whether or not a cow is expected to be a late calver next year will impact your management decisions in terms of culling. Days in calf from scanning will increase the accuracy of C.O.W. rankings.

Level of destocking will differ from farm to farm. C.O.W. will rank all cows with information in your herd and can be used as a guide to aid you in your decision making.

The C.O.W. is available on the ICBF app as well as by logging in through the ICBF website.

Please note you must be a HerdPlus member, milk recording and predominantly a spring-calving herd to run the C.O.W. profile.

Non-seasonal herds are asked to register their interest to HerdPlus if they want to aid in the development of a C.O.W. profile for non-seasonal systems.

Dr. Kelleher is a quantitative geneticist for the Irish Cattle Breeding Federation (ICBF)