Evaluation of false transrectal ultrasonographic pregnancy diagnoses in sheep by measuring the plasma level of pregnancy-associated glycoproteins Aly Karen, Jean-François Beckers, Jose Sulon, Bouchra EL Amiri, Krisztián Szabados, Sanaa Ismail, Jenö Reiczigel and Ottó SzenciReprod. Nutr. Dev., 43 6 (2003) 577-586DOI: https://doi.org/10.1051/rnd:2004005