Cold shock occurs when semen is thawed and then subjected to cold environmental temperatures before being deposited in the cow or heifer. It's important to take special precautions when handling bull semen during cold weather because cold shock damages sperm cells and reduces fertility.
Here are some timely reminders for minimizing cold shock from George Heersche, Jr., extension dairy specialist at the University of Kentucky:
1. Make sure the animal to be inseminated is caught before the semen is thawed.
2. Minimize the distance between where the semen is thawed and where the animal is inseminated.
3. Thaw and handle semen in a warm room.
4. Before the straw is placed in the insemination gun, warm the insemination gun by rubbing it briskly with a paper towel.
5. Wrap the assembled insemination rod in a clean paper towel and tuck it in your clothing close to your body to keep it warm during transport to the animal.
Source: January 2012 Kentucky Dairy Notes