Nortestosterone: endogenous in urine of goats, sheep and mares?

For a number of species it is known that nortestosterone, either the alpha- or beta-epimer, can be of endogenous origin. For goats and mares similar r esults have not yet been published. As a follow-up on the experiments with cattle, a large number of urine samples per animal were collected from preg nant goats, sheep and mares. These samples were analysed for the presence o f alpha- and beta-nortestosterone and alpha-estradiol using CC-MS. The resu lts show that in the goats and mares studied alpha-nortestosterone is prese nt during pregnancy. In this study no alpha-nortestosterone could be demons trated in sheep. From our study and recently published data, however, it is proven that alpha-nortestosterone can occur endogenously.