Many cattle breeding programs were initiated in Africa to increase the productivity of indigenous cattle breeds. Most of these programs have failed, partly due to the lack of involvement of breeders. The present case study contributes to the understanding of such failures. The N’Dama cattle breeding program in Senegal was taken as a case study for an in-depth analysis of participation using mixed methods. Semi-structured interviews were conducted with 52 breeders: 26 who participated, 15 of whom recently resigned, and 27 who had never participated. Content and statistical analyses were conducted to evaluate the motivations of breeders and the factors influencing their participation in the breeding program. Results more particularly highlight the complexity of social issues within a breeding project, in face of classical determinants of adoption that are distance or production systems features. It pinpoints crucial levers of improvement, i.e., the management of animal property rights between the nucleus management and the participating breeders, the legitimacy of participants’ representatives in cooperatives, and the strategic mobilization of member social networks. Also, adding on previous works of the authors, this study highlights the need to take better account of the dynamics of production systems, then paying sufficient attention to the objectives, preferences, and ongoing strategies of the breeders for the future. The present study is the first to highlight the added value of mixed methods to analyze innovation adoption and participation in a livestock breeding program, taking both into account the overall innovation drivers and dynamics tied to actors’ strategies.