Pregnancy-associated glycoproteins (PAG) detection in milk samples for pregnancy diagnosis in dairy goats

In ruminants, glycoproteins synthesized in the outer layers of the trophobl ast enter the maternal bloodstream. The assay of their concentration in pla sma or in serum can be used for pregnancy diagnosis and to indicate feto-pl acental health status. In this study, concentrations of the pregnancy-assoc iated glycoprotein (RAG) were investigated in the milk of dairy goats. The mean concentrations of RAG in milk were significantly higher in pregnant th an in non-pregnant goats throughout the sampling period. Positive milk RAG levels were found in all pregnant animals from Day 32 after breeding, but r emained at negative values in nonpregnant ones. This study reports for the first time a pregnancy diagnosis based on milk concentrations of RAG, that could be of great use on the farm, (C) 2001 by Elsevier Science Inc.