Differential adherence enrichment of buffalo SSCs. A, Testes from a 3 month-old buffalo; B, in gelatin-treated culture dishes, testicular somatic cells adhere to the surface of the dish before germ cells, and germ cells do not adhere firmly; C, when purified in a culture dish coated with rat tail collagen, the adherent cells mainly consist of spermatogonia; D, co-culture of separated germ cells with STO; E, separated testicular somatic cells (mainly Sertoli cells).