ABSTRACT THE use of artificial insemination for the larger strains of turkeys has become a necessary practice for economical poult production. The availability of satisfactory turkey semen diluents would greatly facilitate practical artificial insemination programs. Most attempts to develop turkey semen diluents have involved inorganic buffered salt solutions with some additions of carbohydrates and amino acids. Gilbreath and Davis (1949) reported greatly reduced fertility following 1:10 dilutions with a 0.85% NaCl solution, while fertility was markedly reduced by 1:100 dilutions of a synthetic diluent used by Moravec, Mussehl and Pace (1954). Unfortunately, the exact formulation of the latter diluent was not included, being referred to only as “S-2 solution.” Moore et al. (1955) have reported that the use of an “extender fluid” at a 1:4 dilution rate resulted in a level of fertility equal to that obtained by insemination with undiluted semen. However, additional studies involving this diluent would be desirable . . .