[en] In ruminants, glycoproteins synthesized in the outer layers of the trophoblast enter the maternal bloodstream. The assay of their concentration in plasma or in serum can be used for pregnancy diagnosis and to indicate feto-placental health status. In this study, concentrations of the pregnancy-associated glycoprotein (PAG) were investigated in the milk of dairy goats. The mean concentrations of PAG in milk were significantly higher in pregnant than in non-pregnant goats throughout the sampling period. Positive milk PAG levels were found in all pregnant animals from Day 32 after breeding, but remained at negative values in nonpregnant ones. This study reports for the first time a pregnancy diagnosis based on milk concentrations of PAG, that could be of great use on the farm.
Disciplines :
Veterinary medicine & animal health
Author, co-author :
González, F; Reproduction and Obstetrics, Faculty of Veterinary, Las Palmas de Gran Canaria, Spain
Sulon, J; Physiology of Reproduction, Faculty of Veterinary Medicine, Liège, Belgium
Calero, P; Reproduction and Obstetrics, Faculty of Veterinary, Las Palmas de Gran Canaria, Spain
Batista, M; Reproduction and Obstetrics, Faculty of Veterinary, Las Palmas de Gran Canaria, Spain
Gracia, A; Reproduction and Obstetrics, Faculty of Veterinary, Las Palmas de Gran Canaria, Spain
Beckers, Jean-François ; Université de Liège - ULiège > Département des sciences fonctionnelles (DSF) > Physiologie de la reproduction ; Physiology of Reproduction, Faculty of Veterinary Medicine, Liège, Belgium
Language :
English
Title :
Pregnancy-associated glycoproteins (PAG) detection in milk samples for pregnancy diagnosis in dairy goats.
In 1991, Zoli et al. (26) purified a PAG family from bovine fetal cotyledons. Antisera were raised in rabbits against this protein and a specific RIA was developed that allowed detection of pregnancy in cattle from Day 30 after breeding (27). Antigens immunologically related to bovine PAG were isolated from ovine fetal cotyledons (25). The PAG could be detected in plasma of pregnant ewes by a heterologous RIA: detectable PAG levels could be found in some ewes 3 weeks after mating and in all pregnant animals by 4 weeks (14). The same heterologous RIA could Acknowledgments Supported by Agriculture Ministry and FNRS grants to J.F. Beckers and by Consejeria de Education del Gobierno de Canarias grants to F. Gonzalez. The authors thank Dr. J.M. Garbayo (Department of Animal Sciences and Biochemistry, University of Missouri-Columbia) for revision of the manuscript. We are grateful to National Institute of Health (USA) for the gift of hormones. “Correspondence and reprint requests: Reproduction and Obstetrics, Faculty of Veterinary, University of Las Palmas de Gran Canaria, 35416 Arucas, Las Palmas, Spain.
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