Accurate on-farm fertility testing

A person in farm attire, including a cap and jacket, standing in a grassy field with Black and White cows grazing during sunset.

Real-time milk progesterone testing for dairy cows.

Proven. Precise. Predictable.

Be sure before you breed.

>97% accurate¹

—Progesterone is the gold standard for confirming heat²⁻³

P4 HeatRead™

1. P4 Science. P4 Heatread internal validation. 2026
2. McLeod BJ, Foulkes JA, Williams ME, Weller RF. Predicting the time of ovulation in dairy cows using on-farm progesterone kits. Anim Prod. 1991;52(1):1–9.
3. Bulman DC, Lamming GE. The use of milk progesterone analysis in the study of oestrus detection, herd fertility and embryonic mortality in dairy cows. Br Vet J. 1979;135(6):559–567. doi:10.1016/s0007-1935(17)30010-6.
4. Roelofs JB, van Eerdenburg FJCM, Hazeleger W, Soede NM, Kemp B. Relationship between progesterone concentrations in milk and blood and time of ovulation in dairy cattle. Anim Reprod Sci. 2006;91(3–4):337–343. doi:10.1016/j.anireprosci.2005.04.015

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Progesterone: A brief overview

Learn about the critical role of progesterone in cow oestrous cycles, pregnancy maintenance, and how rapid milk tests improve heat detection on the farm.