The 5 deg. C. thawing temperature resulted in a higher percentage of sperm survival at all the glycerol levels than 38 deg. C., with the difference in favor of 5 deg. C. becoming greater as the glycerol level increased. The reason for the interaction between glycerol level and thawing temperature is not known. It may be that the presence of the higher levels of glycerol at 38 deg. C. brought about harmful metabolic activity. The difference in survival of sperm in semen thawed at 5 deg. C. and at 38 deg. C. continued during storage at 5 deg. C. (Table 15). It was also evident that the interaction between glycerol level and thawing temperature continued during storage (Fig. 7). [Illustration: Effect of thawing temperature on sperm motility during storage at 5 deg. C. following freezing and thawing (Fig. 7)] Table 15.--Effect of Glycerol Level, Thawing Temperature, and Storage at 5 deg. C. After Thawing on Sperm Motility (Average of 13 ejaculates) ===================================================================== Thawing Glycerol Sperm motility (percent) temperature level ------------------------------------------- ( deg. C.) (percent) Post- After storage at 5 deg. C. thawing ---------------------- Average 1 day 3 days --------------------------------------------------------------------- 38 4 28.5 17.3 5.1 17.0 6 31.5 22.4 9.2 21.1 8 33.1 15.0 4.6 17.6 10 19.5 3.6 0.8 8.0 Average 28.2 14.6 4.9 12.2 5 4 29.2 21.7 19.8 23.9 6 37.7 33.8 23.5 31.7 8 41.5 33.1 17.3 30.6 10 33.1 18.5 6.0 19.2 Average 35.4 26.8 16.6 20.6 ---------------------------------------------------------------------