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Pregnancy diagnosis through routine milk testing

Using Alertys Milk Pregnancy Test can't be any easier

Minimal labour, minimal expense, maximum benefit

The most productive cow is a stress-free cow.

That's why we've developed an alternative to the conventional pregnancy diagnosis, offering all the accuracy without any of the hassle. 

The Alertys Milk Pregnancy Test is a convenient pregnancy diagnosis for dairy cows. Simple and >99% accurate¹, it uses the same milk you collect for your routine milk recording.

Besides, you can use self-sampling pots and have them posted directly to your milk recording organisations (This option is only available to some Milk Recording Organisations).


It’s that easy. No additional work is needed. No extra handling, no separate testing, no extra stress - for your cows, or for you.


¹Lawson, Bradley & Shahzad, Abid & Dolecheck Borchers, Karmella & Martel, Edmond & Velek, Katherine & Ray, Denise & Lawrence, John & Silvia, William. (2014). A pregnancy detection assay using milk samples: Evaluation and considerations. Journal of Dairy Science. 97. 6316-25. 10.3168/jds.2014-8233. 

Good for the farm


You’re already having your milk tested, what about adding another test?

Milk pregnancy test means no additional work.


Once-a-month testing not enough? It’s quick and easy to send further samples if more regular testing is needed.


The test is accurate just 28 days post-AI. Think of the test not as a pregnancy confirmation tool, but as an 'alert' to open cows. Have the lab notify you when a cow isn’t pregnant and then have your Vet focusing on these ‘problem’ cows, rather than pregnancy checking every cow.


By spotting these cows earlier, you can reduce calving intervals and save money. Research shows that the average cost per open cow is €5/day². Leaving just one cow open 20 days longer than expected could cost you as much as €100.

Good for the cow

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Alertys Milk is a simple, non-invasive test for pregnancy diagnosis in the dairy cow. 

It needs no rectal exam and no palpation, so there’s no need to gather and handle cows for testing.


It is stress-free for the cow and risk-free for the growing foetus. 

Alertys Milk prioritises cow comfort, because happy cows are healthy cows.

²French PD, Nebel RL. The simulated economic cost of extended calving intervals in dairy herds and comparison of reproductive management programs [Abstract]. J of Dairy Sci. 2003:86(suppl):54. Cited by: de Vries A, van Leeuwen J, Thatcher WW. Economics of improved reproductive performance in dairy cattle [Publication AN156]. Gainesville, FL: University of Florida, Institute of Food and Agricultural Sciences; 2005

Good for the Vet


Farms using Alertys Milk enjoy a more constructive, more efficient relationship with the Vet. 

There’s no need to perform a pregnancy diagnosis on all cows in the herd.


Vets instead focus on the cows that really need attention: those that are sick, those that have aborted, or those that aren’t getting in-calf.

What’s more, less time spent on collecting data – essentially, performing pregnancy diagnosis tests - gives you and your Vet more time available to spend on proactive herd management, such as herd health plans: devising and refining strategies to improve fertility, minimise lameness, maximise milk production and optimise profitability.

What could be simpler?

An all-round smart package that's hands-on, not hands in

Tierarzt trächtige Kühe
Reproduktionseffizienz Landwirtschaft

No unnecessary stress for the cows because they neither have to be examined rectally nor locked up

Non-invasive and no risk to the cows

No extra effort: easy to include in your routine milk control. And thus a time saver

99% accuracy¹ from day 28. As accurate as veterinary advice

Your Vets can use their precious time to take care of the open cows

Ideal for optimising reproductive efficiency. Open days and losses are recognised in good time

Are you using milking robots?
That's even better!

Alertys Milk Pregnancy Test comes with greater benefits when integrating with robotic farms:

Pregnancy results with no need to block the cowsless stress and less traffic jams at the robot

Less somatic cells and lameness cases as cows spend less time standing and waiting

Early and frequent pregnancy checks result in more cows in calf and better farm profitability

Don't just take our word for it...

Gaëtan Le Roux

Gaëtan Le Roux

80 cows, Finistère

"With BCEL Ouest/Innoval, we conducted a pregnancy test trials based on milk samples taken with the milking robot VMX 300 DeLeval. The results have been proven to be very reliable and I've been using the test regularly since."

Jorgen Sonderby

Jorgen Sonderby

390 cows, Jutland, Denmark

"We have been using the milk pregnancy test in the past 5 years. At the beginning, we weren't sure if the test worked, but uptil now, we are trusted it 100% and using this method mainly to check for cow's pregnancy."

Dominik Bakowicz

Dominik Bakowicz

115 cows, Poland

"As of 2020, I started using the milk pregnancy test in my routine tasks. In addition to testing using the milk recording samples, I also use the self-sampling kit of the test. It's very simple and helps me improve reproduction in my herd"

Alina Lis-Rosiak

Alina Lis-Rosiak

30 cows, Poland

"It's a fast and effective method of pregnancy test, with no stress for my cows!"

Tobias Blank

Tobias Blank

60 cows, Northwestern Germany

“Significantly less effort for me and absolutely stress-free for my cows. For me, these are the advantages of the milk pregnancy test.”

Christopher James

Christopher James

1200 cows, Pembroke

"The test’s biggest benefit is that we’re no longer having to handle the cattle. It’s one less job, it’s non-invasive, and it’s stress-free both for the herd and our team at a busy time of year, which also has the added workload of TB testing."

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Over 38 millions Alertys tests have been performed by hundreds of milk recording organisations/labs worldwide

MIlk info form

Make your farm and your cows stress-free!

Interested in trying out Alertys Milk for yourself? Just like the test itself, it’s easy to arrange. Just fill out the form and we’ll liaise with your milk recording organisation to send you all the necessary information, including prices and different testing options. 

That's it! You are on your way to hassle-free, stress-free, and accurate pregnancy testing with Alertys Milk. Thanks for completing the form. Our information pack should soon arrive in your inbox (although there is a small chance it might go to your junk or spam folder; please check that too!).

  • What is PAG and how do the Alertys tests detect it?
    ​PAG is shorthand for Pregnancy-Associated Glycoprotein. The PAG test which has been developed by IDEXX is called the Alertys Pregnancy Tests*. It is an enzyme-linked immunosorbent assay (ELISA) test. It has been developed to accurately detect PAG molecules in blood, serum or milk. It is validated to be used for pregnancy diagnosis in cattle, sheep, goats, water buffalo and bison. Unlike other chemical tests for pregnancy using progesterone as an indicator, the PAG test is very specific for pregnancy. *The Alertys Rapid Visual and OnFarm pregnancy tests can be run without ELISA instrumentation.  PAGs are detectable as early as 28 days after insemination, so it is recommended that the test can be used from this point and throughout the whole gestation period.
  • What lab equipment do I need to perform the Alertys Milk and Ruminant Pregnancy Test?
    For performing these tests, you should have a lab equipped for ELISA testing, including pipettes, pipette tips, distilled water, a 96-well plate reader, a microplate washer, and a plate shaker/incubator. All details can be found in the kit inserts.
  • What is the difference between PAG and Progesterone?
    Progesterone is a hormone that occurs with peaks and valleys during the normal reproductive cycle and is not pregnancy specific. The Alertys pregnancy tests detect pregnancy-specific proteins called pregnancy-associated glycoproteins (PAGs). These specific proteins are expressed in the embryonic regions of the placenta and detected in maternal fluids such as blood and milk.
  • What are the differences among IDEXX Alertys products?
    The Alertys Milk Pregnancy Test uses milk samples collected during routine milk recording or collected from self-sampling pots, which will be most suitable for dairy farms. The test cannot be performed on-farm as specialist laboratory equipment is required. The Alerty Ruminant Pregnancy Test, which uses blood samples, on the other side, may be more convenient for beef herds. Again, the samples are tested in a lab as specialist equipment is required. For smaller-scale testing organisations, such as individual veterinary practices, the Alerty Rapid Visual Pregnancy Test can be used. A blood or serum sample is required, and the test can be completed in around 30 minutes. Some technical skill is required, and this isn’t a cow-side test, but there is no necessity for specialised laboratory equipment to observe the colour change to make a pregnancy diagnosis. Finally, there is an Alertys OnFarm Pregnancy Test, which was recently introduced in 2021. This lateral-flow style test can be used on farm and requires no technical expertise, other than to collect a blood sample (EDTA sample). A measured amount of blood is dropped onto the test cartridge, and a pregnancy diagnosis result is ready in a matter of minutes, not unlike a human home-pregnancy test kit. This is suitable as a cow-side test.
  • What is the return on investment from using Alertys tests?
    Open cows can have a major impact on profitability. Research shows that the average cost per open dairy cow is €5 a day*. These costs include the value of the milk the cow would have produced, the value of her calf, and other relevant factors. Dairy farms can optimise profitability by shortening the calving interval and reducing the number of days that cows are open. For beef farmers, shorten calving intervals with safe, ongoing confirmation of pregnancy status at critical stages, saves an estimated $77 per head** by identifying and removing sub-fertile cows early. * De Vries et al, Economics of improved reproductive performance in dairy cattle (Publication AN 156), Gainesville FL, University of Florida Institute of Food and Agriculture Science; 2005 ** Cook B, Biermacker JT, Childs D. The value of pregnancy testing beef cows. Paper presented at: 2007 Southern Agricultural Economics Association Annual Meeting; February 4–7, 2007; Mobile, Alabama.
  • Can all the Alertys tests tell anything else besides pregnancy?
    No, the test will provide a pregnant, open/non-pregnant or 're-check' result. It cannot tell the stage of gestation, the sex of the calf or if the cow is carrying multiple calves.
  • Why test more than once during gestation?
    During the normal gestation process of a cow, approximately 10-25% of pregnancies will be lost between conception and full-term due to unknown causes. Pregnancy testing at specific times throughout gestation helps improve reproductive efficiency by finding cows who have experienced pregnancy loss. It is recommended to test 2-3 times throughout gestation; first at 28-30 days post- breeding, again at 60 days post-breeding, and before dry off to be sure only pregnant cows are kept on farm.
  • Does PAG testing replace the need for a Vet?
    It is clear there is a strong case for early and accurate pregnancy diagnosis in dairy herds. The method used for pregnancy diagnosis is somewhat a matter of personal choice, depending on individual circumstances and convenience. Both transrectal ultrasound (TRUS) and PAG testing are reliable methods of early pregnancy diagnosis. Most dairy farms find that working closely with a progressive veterinary practice carries many benefits. This remains the case whether you choose to use the Vet for TRUS pregnancy diagnosis, or not. Of course, transrectal ultrasound can play a role in other areas of fertility management too, such as diagnosis of non-cycling or cystic cows. A mix-and-match approach can be a sensible way forwards for many herds, taking advantage of PAG pregnancy diagnosis for its timeliness, simplicity, and accuracy, whilst reducing the numbers of cows needing to be separated and presented at the routine vet visits. Some farms find this then frees up their Vet to focus on valuable tasks, such as fertility data analysis, training, and other beneficial work.
  • Is there an influence of breed on all the tests?
    No breed influence on test performance has been described.
  • Do antibiotics influence the PAG tests?
    IDEXX has no evidence to date to suggest that antibiotic treated milk has a negative effect on the test results.
  • After early embryonic losses or abortion, does the test still detect PAGs?
    Yes, PAGs will circulate in milk and blood for a certain period of time after embryonic loss or abortion. For early embryonic loss, we estimate PAGs will disappear within 6-10 days. In case of late term abortion PAGs may be present for a longer period of time (40-60 days). It should be noted that it can take up to 60 days for PAGs to drop below the test threshold post-calving.
  • I have a bull in my herd or use a bull at the end of my AI period. Can I still use PAG testing methods?
    You can still use one of the Alertys tests, you just need to apply some rules around testing. For example, test 50 days after the cow is put with bull (21 days for heat plus 28 days to earliest test), or test 28 days after the bull is removed from the herd. If the bull is running with the herd all the time, you may need to test monthly, BUT remember, the test will not tell you how far in calf the cow is. And a negative result does not mean not-pregnant if test is done less than 28 days since service.

Explore Alertys resource below:

Alertys Milk - User Guidance

Developed by IDEXX, this paper presents a decision tree and comparison between 5-plate and 30-plate Alertys Milk Pregnancy Test kit

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Milk Sample Collection Guide

The quality of samples taken for any diagnostic procedure is extremely important. Correct identification and a truly representative sample are critical for obtaining optimal diagnostic test results. Here is a protocol for the manual collection of milk samples for pregnancy testing

Alertys Milk Sample Collection.jpg

Alertys Milk - Pocket Guide

Information about Alertys Milk Pregnancy Test in one place - how it works, why farmers should check for pregnancy in cow early, implementation of the test in dairy farming and some dairy farmers' questions. 

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Do you sometimes need results more quickly?

If so, the Alertys OnFarm might interest you.


It’s a super-fast, ultra-reliable pregnancy diagnosis that can be carried out on-farm, with results in 5 to 20 minutes.

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