Due to their unique properties, stem cells have become an important source for the development of regenerative medicine and tissue engineering in recent years. Since different properties of mesenchymal stem cells (MSCs) in vitro can lead to potentially different therapeutic effects, investigating the influence of various factors on the properties of MSCs is essential. The established basis for the cultivation of MSCs is a plastic surface, but due to the better mimicking of the natural cellular environment, the use of cell carriers for cell cultivation is being increasingly developed. In this dissertation, our studies are systematically divided into two parts. In the first part, cells were grown on a conventional plastic surface and the influence of species, sex and late passages on the proliferation and differentiation potential of canine and feline adipose derived MSCs (AMSCs) were investigated. In the second part, cells were grown on silk fibroin (SF) cell carriers and influence of SF on the AMSCs was investigated. The results of the first part of our study showed that feline AMSCs had poorer proliferation and differentiation potential than canine AMSCs and that late passages had a more negative effect on feline AMSCs than on canine AMSCs. In addition, feline AMSCs expressed fewer examined cell surface markers and exhibited lower viability under less optimal conditions. The results of the first part of the study showed that animal species can significantly affect the properties of AMSCs in vitro and that animal species should be considered when preparing cells for regenerative treatment. The results of the second part of our study showed that SF enables cell adhesion and directs AMSC fate towards chondrogenic differentiation, which was confirmed by the analysis of cell morphology, staining of extracellular matrix of differentiated cells and quantification of genes, characteristic of chondrocytes. With the results of the second part of the study, we have shown that chondrogenic AMSC differentiation can be achieved without the special cell culture conditions that are otherwise required for chondrogenesis of AMSCs on a conventional plastic surface. The results of the dissertation allow us to deepen the knowledge about the importance of the stem cell differences between species and at the same time represent basis for further studies and the potential for the introduction of new stem cell therapies in clinical veterinary medicine.