Charcoal cloth discs to separate free from antibody-bound progesterone.
D000818:Animals; D002417:Cattle; D002606:Charcoal; D007106:Immune Sera; D011374:Progesterone / Q000097:blood* / Q000276:immunology; D011863:Radioimmunoassay / Q000379:methods*; D012016:Reference Values; D012756:Sheep; D013997:Time Factors
D007106:Immune Sera; D002606:Charcoal; D011374:Progesterone