7 ways to make the most of milk recording data

Milk recording can act as an important early warning system, flagging up issues that without intervention could affect herd profitability.

Specialist dairy vet Andrew Bradley says farms which invest in milk recording should be deriving the maximum value from that data because it allows for better-informed decisions in several areas of farm management.

“Searching out the secrets in that data can allow initial indicators of poor performance to be identified and help with the diagnosis of a herd problem,” he says.

See also: UK dairy farmers exceed antibiotics reduction targets

From monitoring mastitis at an early stage of infection to informing management decisions on breeding and culling, Prof Bradley, of Quality Milk Management Services (QMMS) and the University of Nottingham, and milking expert Ian Ohnstad, of The Dairy Group, give their advice on how farmers can make the best use of their recording data.

Ian Ohnstad © MAG/Colin Miller

1. Use data to identify cows at risk of mastitis

Treatment for mastitis, and resulting loss of production, are some of the largest costs to the UK dairy industry.

Recording will pick up infection in its early stages, reducing future financial losses.

Recording allows for the monitoring of mastitis by providing somatic cell count (SCC) readings for individual cows. A threshold of 200,000 cells/ml is generally accepted as an indicator of mastitis incidence.

“Picking up those signals allows the farmer to get on top of the issue before it becomes a problem,” says Prof Bradley.

This is because a rise in the rate of new infection will be identified in individual cows before it becomes evident in bulk milk sampling.

“The bulk milk reading might not change at all in the first month of infection, because of the dilution effect with milk from other cows,” he says.

“By not picking it up in its early stages, an infection is more likely to progress to a chronic stage.”

There are additional tools that can help farmers with this. AHDB, in conjunction with the University of Nottingham and QMMS, has launched the mastitis pattern analysis tool, QuarterPro, to help farmers identify when most mastitis infections occur in a herd.

A report is automatically sent to a farmer after every milk recording.

2. Record consistently

The gold standard of milk recording is monthly, monitoring individual cows through their lactation and plotting patterns and changes in infection at a herd level.

Changes in cell counts can show whether the origins are environmental or contagious mastitis, and whether the problem is associated with lactation or the dry period.

“Some herds are settled in their pattern – they change little – but if the infection problem changes from environmental to contagious, farmers will start to see a pattern forming,” says Mr Ohnstad.

To limit the cost of monthly recording, some farmers opt for “factoring”, where a sample is taken from one milking only on the day of recording – this might be the morning milking in January and the afternoon milkings in February and March, for example.

However, morning and afternoon milking intervals usually differ, and that will have an influence on the SCC readings in the data gathered.

While Mr Ohnstad does not advocate factoring, he says if farmers are using the system they should be consistent and opt to always record in the morning or always in the afternoon.

Never make management decisions based on one recording for an individual animal, he advises.

“If the herd is block calving, a minimum of three months of milk records is needed, ideally four or five. The more data you have the better informed you are.”

3. Use data to inform drying-off policies

With pressure on dairy farmers to reduce antibiotics usage, more are adopting selective dry cow therapy (SDCT) as a strategy to achieving that.

But to do that safely, they should have a very clear picture of the health of individual cows, says Mr Ohnstad.

“If a cow doesn’t have an underlying infection, she is a candidate for teat sealant only; if not, she will need to be dried off with a dry cow tube,” he advises.

“If farmers are averse to monthly milk recording and only test towards the end of lactation to inform their drying-off policy, this is pretty dangerous.”

4. Base decisions on up-to-date data

When data is limited because milk recording is not done regularly, ensure it is gathered as close as possible to the point where a decision will be made.

“Don’t make decisions about drying off on data that is eight weeks old because cow health may well have changed since that was gathered,” says Mr Ohnstad.

Use individual cow SCCs from three consecutive milk recordings, alongside clinical mastitis history for the past three months, to determine individual cow infection status, he adds.

5. Use data to improve herd genetics

The most obvious benefit of milk recording is that it allows the best and worst producers in a herd to be tracked.

Milk recording records allow farmers to evaluate their herds’ genetic potential, says Prof Bradley.

“This allows the farmer to make management decisions such as which cows are underperforming and may be suitable to cull, or which cows are producing in the system and are more suitable for breeding replacements.” 

Milk recording information can help farmers identify the most profitable animals, for instance, those that are high yielding, producing high-quality milk and with strong genetic merit, for breeding dairy replacements and informing culling decisions.

Improved productivity through milk recording can also be beneficial from an emissions mitigation perspective due to efficiency gains, he adds.

6. Use data to check fat:protein ratio

This ratio is calculated by dividing the percentage of fat in the milk by the percentage of protein. In early lactation, if the ratio is greater than 1.4, the cow is probably in negative energy balance. This means too much body fat is being mobilised, increasing the risk of metabolic disorders and associated poor health and fertility.

7. Use milk protein data when reviewing herd diet

Many factors influence milk protein levels, in particular energy levels and rumen function, both of which are essential. However, a drop in protein may indicate that cows are short of digestible undegradable protein and essential amino acids.

This commonly occurs when cows have lost so much condition in early lactation that they have mobilised muscle as well as fat and are using protein in the diet to rebuild muscle.

When this occurs, a review of the cow diet is recommended.