The constant ratio of the zinc content of boar spermatozoa of 4 degrees C and room temperature.

The ratio of the zinc content of boar spermatozoa obtained from semen cooled to 4 degrees C for 30 min to that of the original room temperature control (20-26 degrees C) was constant at 2-28 +/- 0-16 in 22 samples of fresh whole semen from 12 animals. The same ratio occurred when zinc (0 to 0.6 mM in citrate buffer) was added to semen or washed spermatozoa. The increase is dependent only on the initial sperm zinc content at room temperature.