Extending, Storing and Shipping Stallion Semen

Considering that it takes some powers of persuasion to obtain a semen specimen from a stallion, it is judicious to handle the sample in a manner that does not cause excessive damage to the spermatozoa. Over the last century, many common semen handling techniques unknowingly abused the prized sperm.

Spooning, which is the recovery of the semen from the floor of the mare's vagina, usually occurred by using a metal spoon washed in soap and water. Fragile equine sperm cells cannot survive contact with cold metal surfaces, nor can they tolerate electrolytes in their environment. Any solution or surface that is a good conductor of electricity (i.e., a metal spoon) is not good for sperm. Soap film is lethal and millions of sperm can be killed simply by coming in contact with the surface of a spoon or container rinsed well in tap water.

Only distilled water, free of any electrolytes, should be used to rinse an object coming in contact with the spermatozoa. It is also better to use glass or plastic containers, tubes, and spoons. These minor changes will prevent the assassination of more than half of the sperm cells by equipment with lethal surfaces.

From research done at the University of Maryland, we found that age of the mare at foaling, sex of the foal, and time of year bred contributed to the length of the pregnancy.

Statistical analysis showed that the calculation of length of gestation related to these factors was a much more accurate estimate of the normally used 340 day average.

Later research showed that the best estimate of a specific mare’s length of gestation was determined from prior pregnancies. Without this kind of individual mare data, this chart is usually a better estimate for the length of gestation than the 340 day average.

How to Use the Chart: Locate the age of the mare at time of foaling along the top of the chart, then locate the date she was last breed along the side. Follow the column down and the row across till they intersect. This is the predicted foaling date. For example, the line is highlighted in the chart what predicts the foaling date for a mare that will be 15 years old when she foals and that was bred on March 2nd. It predicts that she will foal about February 17th.

There is a 6 day foaling window around this date. On the average colts are 3 days early and fillies are 3 days late.

Remember that the best estimate of the length of a mare's pregnancy comes from the record of prior pregnancies. However when that information isn't available, this Chart may prove a valuable tool.

An excerpt from The Stallion: A Guide for Owners and Handlers

by James P. McCall, PhD

Click on the image to open the chapter on Hand Breeding Stallions

Late one cold spring night in Maryland, we had just finished foaling out a young first-foal Thoroughbred mare when a group of graduate students stopped by the farm on their way home from a party. In the spirit of things, they continued their partying outside the foaling stall, laughing, joking and carrying on. The young mare, experiencing some abdominal cramps, became disoriented and frightened by the noise. A cramp hit her and she collapsed onto the ground. After a moment , she got up and started to spin round and round getting increasing excited by the noise.

Immediately it became apparent that the life of her newborn foal lying helplessly in the middle of the stall was in jeopardy. Rushing into try and save the foal from being crushed, the mare nearly trampled both her foal and its human protector. Quickly the partying college students realizing that their college professor was in a life-threatening situation decided they' ought to find a better place to continue their party.

Within minutes the mare quieted down and Jim placed the foal back in the stall. Fortunately the mare sniffed her foal and began licking it. Nature took over and the maternal business of nurturing her newborn began again.