What is BioPRYN®

BioPRYN® is a pregnancy detection tool for use in cattle. It measures the presence of Pregnancy-Specific Protein B (PSPB) in the blood circulation of the animal. The PSPB protein is only produced by the placenta of the growing fetus. Cows and heifers must be at least 28 days post-breeding and cows must be at least 73 days post-calving. There is a chance for a false positive if the residual PSPB has not cleared the maternal system from cows that have calved more recently than 73 days ago.

How BioPRYN® works:

Dairy Diagnostics Logo

BioPRYN® begins with collection of a blood sample from the animal. The samples are then shipped to our laboratory where an enzyme-linked immunosorbent assay (ELISA) is performed. Reports may be downloaded directly into dairy management software or sent via email or fax.

Using BioPRYN assures accuracy. The accuracy is 99 percent when the test determines an animal open, giving producers confidence to administer a prostaglandin shot and restart a synchronization program. There is as much as a 5 percent false-pregnancy rate from the test, primarily due to early embryonic death which is a challenge regardless of which method is used for pregnancy detection.

How to collect blood:

First obtain vacuum blood collection tubes and needles and a needle holder sleeve.  We recommend 10cc  red top evacuated blood collection tubes and 1 inch multiple draw  18 or 20 Gauge  needles.  These tubes contain no anticoagulant.  We can supply collection tubes, needles and holders if you need them.  Use a new needle for each animal to avoid cross contamination of serum.  We will need at least 2 cc of  blood so the tube should be at least 1/3 full. The blood can be obtained from the jugular vein or more commonly from the tail vein.  Get more information on tail bleeding.

Handling and Shipping:

test tube

Label tubes sequentially starting with 1.  Add the animal ID when the blood is obtained as shown above.  Hold the collected sample at room temperature for at least 30 minutes to allow the blood to clot and then place in a refrigerator until shipment.

Shipping Instructions:

We are currently starting the BioPRYN® assay on Wednesday and reporting results on Thursday. Please plan your shipments accordingly.

Ship collected blood via overnight or 2 day shipment. It is not necessary to ship the samples on ice but it is necessary to pad the shipment well. Wrap each tube individually in a paper towel or bundle several tubes together and wrap with bubble wrap. Place entire shipment in a leak proof plastic bag and place bag in a shipping box with additional padding. Do not use a padded envelope for shipping blood. Enclose a completed submission form (pdf) in the box.


The BioPRYN® pregnancy assay is initiated weekly, on Wednesday, for results Thursday morning. All samples received after the regularly scheduled test day will be held for the following Wednesday assay. The cost per sample is $3.25.
Samples needing “early” results may be initiated on Monday, Tuesday, Thursday and Friday for an additional fee. The price per sample would then be $8.00. Same day results may be available for samples that arrive by noon, 12pm, on the day results are needed. Please call to notify the laboratory if early results are needed.

Download the submission form.

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