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Virginia Cooperative Extension -
 Knowledge for the CommonWealth

Cold Weather Breeding Tips

Dairy Pipeline: January 1997

by Ray L. Nebel
Extension Dairy Scientist, Reproduction
Virginia Tech

With winter comes cold weather and the increased danger of cold shocking of semen. Cold shock causes loss of motility, sperm metabolic activity and fertilizing ability of sperm. Cold shock occurs when semen is thawed and then subjected to cool or cold environmental temperatures before reaching the cow. The severity of damage depends on rate and duration of temperature drop. A routine maintenance check of the thermometer is also recommended and should be performed with a mercury reference thermometer at the same temperature that you thaw semen (hopefully 95 F). Here are precautions to take to minimize cold shock: (1) While semen is thawing, warm the insemination rod by rubbing briskly with a paper towel. Touch the rod to your cheek to determine if it is warm enough. It should be roughly body temperature. (2) Place the assembled insemination rod within a plastic AI sleeve to prevent contamination and tuck it in your clothing so it will be close to your body and maintain warmth during transport to the cow. (3) Inseminate the cow within minutes after semen has been thawed. The period of time between straw removal from liquid nitrogen and semen deposition in the cow should be as short as possible, but do not rush because that is when mistakes are usually made. If at all possible semen should be thawed and handled in a warm room or at least inside out of cold or subfreezing weather.

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