The production of Pyrenean suckling lambs is a way to contribute to the economic activity of the Pyrenees, the maintenance of sheep farmers, the preservation of the environment and the life of the region. In order to defend this product, it is necessary to re-evaluate precisely the interest of crossbreeding between local dairy breeds and local Pyrenean meat breeds, in terms of growth gain and weight at slaughter, but also of conformation and adaptation to the market. The trial compared purebred lambs and lambs crossed with either beef breeds or the Montagne Noire breed. In accordance with feedback from the field, purebred lambs had lower growth performance and lighter slaughter weight and carcass weight than crossbred lambs. Crossbreeding seems to affect fat color and especially the yellow index (b*): purebred lambs' fat is significantly less yellow than crossbred animals. Crossbreeding also affects the color of muscles, the lambs crossed with Montagne Noire and purebred having lighter meat than lambs crossed with other breeds. In our work, we found that purebred lambs were slightly tougher than Black Mountain crossbred lambs and significantly tougher than lambs from other crossbreeds. This exploratory work thus provides the first characterizing elements of breeds and crosses that have been, until now, little treated in the literature.