[en] The development, the establishment and the embryonic survival at early stages of gestation are depending on an intimate dialogue between the embryo and his mother. For the embryo part, it is especially the trophoblast, or the future placenta, which plays a key role in initializing pregnancy. The placenta emits many signals of various chemical natures ( steroids, prostaglandins, peptides, proteins), some of them, e. g. the interferon tau, determine the maintenance of the corpus luteum at the beginning of gestation. Until now, although having raised many speculations, the earliest of these signals were not identified in peripheral circulation. Consequently, they cannot be used as a pregnancy diagnosis or to indicate embryonic mortality. However, since the eighties, the specific proteins "associated with pregnancy", produced by the trophoblastic cells are used as tool for breeding management. Most of these molecules are present in peripheral circulation. In this review, we will describe the major mechanisms associated with the maternal recognition of the gestation and their possible applications as pregnancy diagnosis tool in the cow. [fr] Le développement, l’implantation et la survie embryonnaire à des stades précoces de la gestation sont dépendants d’une communication embryo-maternelle intime. La partie embryonnaire est constituée principalement par le trophoblaste, ou futur placenta, qui joue un rôle primordial dès les premiers stades de la gestation. Le placenta émet de nombreux signaux de natures chimiques diverses (stéroïdes, prostaglandines, peptides, protéines) dont certains, comme l’interféron tau, déterminent le maintien du corps jaune en début de gestation. Jusqu’à présent, bien qu’ayant fait l’objet de nombreuses spéculations, les plus précoces de ces signaux n’ont pas été identifiés dans la circulation périphérique maternelle. Cependant, des protéines spécifiques, dites associées à la gestation, ont été découvertes dès les années’80. Ces dernières sont synthétisées par les cellules trophoblastiques et sont utilisées comme moyen de gestion des élevages. Leur avantage est que la plupart de ces molécules se retrouvent dans la circulation périphérique. Nous décrirons dans cette revue de littérature les principaux mécanismes associés à la reconnaissance maternelle de la gestation chez la vache et leurs applications éventuelles dans le diagnostic de gestation
Disciplines :
Veterinary medicine & animal health
Author, co-author :
Ayad, A.
Melo de Sousa, Noelita ; Université de Liège - ULiège > Département de sciences fonctionnelles > Physiologie de la reproduction
Hornick, Jean-Luc ; Université de Liège - ULiège > Département de productions animales > Nutrition des animaux domestiques
Touati, Kamal ; Université de Liège - ULiège > Département clinique des animaux de production (DCP) > Département clinique des animaux de production (DCP)
Iguer-Ouada, M.
Beckers, Jean-François ; Université de Liège - ULiège > Département de sciences fonctionnelles > Physiologie de la reproduction
Language :
French
Title :
Endocrinology of pregnancy in the cow: embryonic signals, placental hormones and proteins
Alternative titles :
[fr] Endocrinologie de la gestation chez la vache : signaux embryonnaires, hormones et protéines placentaires
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