The optimal mating time in the bitch based on the progesterone concentration in the peripheral blood:: a comparison between three ELISA testkits and a 125I-RIA

During oestrus the plasma progesterone concentration can be used to determine the optimal time for mating in the dog. In this study the optimal time for mating for 26 bitches was determined by, measuring progesterone concentrations with three ELISA test kits and a 125I-radioimmunoassay (I-125-RIA). Two observers evaluated the ELISA results simultaneously. They graded the results independently and did not know which dog was being tested. For both observers, the optimal time for mating, based oil progesterone concentrations measured with the Progesterone Small Rapid ELISA test and the Status-Pro test, differed significantly from that based on progesterone concentrations measured by I-125-RIA. Although the optimal time for mating based on the Ovucheck Premate test did not differ significantly 1 Hoofdafdeling Geneeskunde van Gezelschapsdieren, 2 Hoofdafdeling Gezondheidszorg Landbouwhuisdieren. 3 Hoofdafdeling Proefdierkunde, Faculteit der Diergeneeskunde, Universiteit Utrecht Correspondentie: Dr. A.C. Schaefers-Okkens, Hoofdafdeling Geneeskunde van Gezelschapsdieren, Postbus 80, 154, 3508 TD Utrecht Fax: 030-2518126, E-mail: a.c.schaefers-okkens@vet.uu.nl front that based on the 125I-RIA, three out of 14 dogs (21%) for observer one and four out of 14 dogs (29%) for observer two would have been mated on a different act day than that determined on the basis of results obtained with the 125I-RIA. The results did not change when the advised period for mating based an the RIA results was extended by two days. It is concluded that the progesterone concentrations measured with the ELISA test kits tire too inaccurate for clinical use to determine the optimal time for mating. The only reliable results fin, determining the optimal mating period are obtained when concentrations are meas-ured with a RIA.