PROCEDE AMELIORE POUR AUGMENTER L'ACTIVITE SEXUELLE D'OISEAUX ET DE MAMMIFERES DOMESTIQUES UTILES ET POUR PREPARER DES SPERMATOZOIDES CONVENANT A LA REPRODUCTION DE CES OISEAUX ET MAMMIFERES

The invention relates to a process for increasing the sexual activity of birds and useful domestic mammals and for preparing spermatozoa suitable to their propagation. The process of the invention comprises treating sexually mature male birds or useful domestic mammals at least twice and at most four times with 0.1 to 5 mu g/kg of body weight of a compound of the general formula (I), Glp-His-Trp-Ser-Tyr-X1-Leu-Arg-Pro-X4 (I) wherein X1 stands for a glycyl group, a natural or synthetic aminoacid or aminoacid derivative of D configuration, an -Asp-Q group of L configuration, wherein Q is attached to the alpha -carbonyl moiety of the aspartyl group and represents a C1-5 alkylamide, an arylamide, a C1-4 alkoxy or a benzyloxy group; and X4 stands for a glycylamide or a C1-4 alkylamide group, while keeping a pause of at least 30 hours and at most 72 hours between the consecutive treatments. The process of the invention can mainly be used in such large-scale breedings, where artificial insemination is employed but it can be used also for any domestic bird or cought wild-fowl and ornamental bird as well as useful domestic mammal under the conditions of the natural reproduction or artificial insemination.