[Problems relating to low temperature preservation of ram semen. 1. Effects of various cryoprotective agents on sperm].

Studies into the action of several cryoprotective agents in sodium-citrate-yolk diluent on ram semen provided preliminary information regarding both concentration applicable in deep-freeze preservation and toxicity of the agents involved. Included in the tests were glycerin, dimethylsulphoxide, ethylene glycol, propylene glycol, polyethylene glycol, polyvinylpyrrolidome, and dimethylacetamide. The effect of adding cryoprotective-containing diluent at 5 degrees C was more favourable, in its impact on ram sperma, than that observed, when diluent was added at 30 degrees C.