'Serum like' albumin of fowl seminal plasma and effects of albumin on fowl spermatozoa stored at 4 degrees C.

1. Using immunoelectrophoretic and immunodiffusion methods, serum-like albumin was detected in fowl seminal plasma. Immunodiffusion showed seminal plasma albumin concentration to be 4 mg/ml, corresponding to half of the total proteins (8 mg/ml). 2. Replacing seminal plasma with a diluent containing either 1, 4, or 16 mg/ml albumin increased motility of spermatozoa stored for 24 h at 4 degrees C, 16 mg/ml being the more effective dose. 1 and 4 mg/ml had no effect on the fertilising ability of fowl spermatozoa stored for 24 h at 4 degrees C in both young (28-35 weeks old) and old birds (50-55 weeks old). 16 mg/ml albumin had no effect on fertilising rates in young but depressed it in old birds. 3. These results indicate that seminal plasma albumin may be one of the mobility stimulating factors of seminal plasma. However it does not protect fertilising ability better than the diluent alone.