A benefit of the milk pregnancy test

Based on lab analysis of only a few drops of milk, samples can be tested from 28 days post-insemination to find open cows, and throughout gestation to confirm pregnancy status.

Consequences of extra days open in dairy cattle¹⁾²⁾

⬆ Replacement cost

Getting cows back in calf in a timely manner is a fundamental part of good dairy farm management. The economic value of pregnancy testing is to find open cows as soon as possible after breeding. 

Cows with extra days open can result in large economic penalties to a farm (see the graph).

⬆ Culling rate

⬆ Labour cost

⬇ Milk sales

⬇ Feed efficiency

⬇ Calf sales

1 De Vries, A. Determinants of the cost of days open in dairy cattle. Proceedings of the 11th International Symposium on Veterinary Epidemiology and Economics, 2006.

2 De Vries, A. Economic Value of Pregnancy in Dairy Cattle. Journal of Dairy Science 89:3876–3885, 2005.

Profit increased by reducing open days

Average profit improvement for a farm with 100 cows:



£ 9,000

£ 4,500

20 days

10 days

Milk pregnancy test -

an easy solution to detect open cows

The milk pregnancy test detects highly specific markers of pregnancy: pregnancy-associated glycoproteins (PAGs). Unlike progesterone levels that fluctuate naturally during a cycle, PAGs are only produced in the presence of an embryo or fetus.





Sample collection




As part of routine milk control, your samples can be tested for pregnancy specific proteins (PAG's), indicating if a cow is pregnant or not. 

Milk samples are collected and transported to your


Trusted ELISA technology provides accurate results on par with palpation and ultrasound.

Results are reported by text message, email or post.

Note: You can also self-sample and post the sample to the lab.

Your benefits

With just a few drops of milk received at the lab you could:

Confirm pregnancy status throughout gestation

Find open cows as early as 28 days post-insemination

Improve reproductive performance in the herd *

Take timely action to re-breed

*UK studies show that using milk samples for automated pregnancy confirmation (70 -110 days post-insemination) could significantly improve reproductive performance

Detecting open cows throughout gestation

Reproductive performance improves when farmers, veterinarians and breeding companies work together to identify open animals throughout gestation and to take appropriate action.

Day of Insemination



Early pregnancy test

To identify open cows early from 28 days post insemination, which assists in early rebreeding and maintain an optimal calving interval



Confirmatory test

To confirm pregnancy one month after the first check and highlight embryo losses that affect 10-12% of cows. Rebreed open cows while still economically viable

Late gestation

Pre dry-off test

To avoid drying off an open cow producing 20 litres of milk per day, thinking by mistake she is pregnant

Pregnancy for Profit

Progressive advances in dairy fertility with milk pregnancy testing

IDEXX teamed up with CIS in November 2020 to host a ‘Pregnancy for Profit Webinar’ with guest speakers Hilary Dobson, Emeritus Professor at the Institute of Veterinary Science, University of Liverpool, and Owen Atkinson, Royal College of Veterinary Surgeons recognised Specialist in Cattle Health and Production.

In this webinar, they discussed new advances in dairy fertility and covered the following:

• Heat expression, detection, and pregnancy-associated glycoproteins (PAG) testing

• Economic importance of getting cows in calf

• Pregnancy success dependencies

• Vets perspective on the use of PAG testing

Click here to see the main highlights of the webinar!






What our customers are saying

Mr. Christopher James,

Mr. Jim Boyd, 

Mr. Mark Davis,

Mr. Phil Halhead,

 1200 cows, UK

280 cows, UK

220 cows, UK

290 cows, UK

''It’s a simple, practical way of catching those cows not in-calf – it’s not a lot of money for peace of mind!''

> Read more

‘’As a block calving herd, milk pregnancy testing fits in well with our system, and means our Vet can focus their time on the open cows.’’

> Read more

''Since I started using the test, a lot has improved on my farm. The test allows less interference and even problem cows are now getting in calf. This system works well! ''

> Read more

"The milk pregnancy test has been extremely accurate and easy to use. Moreover, it offers less interference and less handling of cows, as well as less stress for both me and the cows."

> Read more

Contact your milk recording organisation

QMMS logo

Reliable, simple, trusted

Developed by IDEXX, a world leader in veterinary diagnostics, Alertys™ pregnancy tests have been performed more than 44 million times since 2010. Milk testing is trusted by tens of thousands of farmers around the world. For more details about the milk pregnancy testing, contact your milk recording organisation.

Do you have any other questions? IDEXX can help you!


IDEXX Alertys Milk Pregnancy Test

This site uses cookies. You can read how we use them in our Privacy Policy | Terms of Use

© 2024 IDEXX Laboratories. All rights reserved.