Frozen Semen
Frequently asked questions:
- Sudden sickness, sterility or even death of your champion.
- Stud dogs sold to another country.
- With some breeds, the stud dog is only allowed to breed a limited number of bitches in his entire lifetime. Only when a stud dog has deceased can his genotype be accurately determined with regards to how he produced and with which bitches (pedigree and type) he “clicked with.” Stud dogs that have long deceased can be reintroduced into the population but then with more certainty as to preserve the lines.
- A canine semen bank can be an ideal solution to help preserve a breed. Famous stud dogs of the past that are known to be outstanding producers can be reintroduced into the population to have their desired characteristics reutilized.
By using liquid nitrogen (temperature of -180 °C), it is possible to prevent the breakdown of biological matter (dog semen). This makes it possible to preserve dog semen for years and years to come.
This question cannot yet be scientifically be answered at the moment. The freezing of dog semen started more than 30 years ago. Semen samples more than 30 years old have been unthawed and examined which revealed that the semen was still viable and healthy. With this semen, bitches have been inseminated giving birth to live and healthy puppies.
Unfortunately this is not the case. Before the semen of the stud dog is to be frozen, it is first critically examined. The concentration, motility and percentage of abnormal cells are examined. During the freezing process some sperm cells will also die. Therefore only semen of good quality can be used to be frozen in liquid nitrogen. If the semen of the stud dog in question is not of good quality, we will strongly advise the owner of the stud dog not to have the semen frozen.
One week after the semen has been frozen, one straw is taken out of the liquid nitrogen tank, thawed and examined (concentration, motility and percentage of abnormal sperm cells). With this method an indication can be made as to how the semen has reacted to the freezing process and this can help make an indication of the fertility and conception rate when the semen is placed in a bitch.
In Sweden a study was done by Prof C. Linde-Forsberg (Faculty of Veterinary Medicine, Department of Obstetrics and Gynaecology, Swedish University of Agricultural Science, Uppsula Sweden) i which the conception rate and the litter size were examined with the use of fresh, chilled and frozen semen using vaginal as well as transcervical insemination.
The results are as follows (from 2041 inseminations):
Semen Type | conception % with vaginal insemination | conception % with transervisal insemination |
Fresh | 47.8 | 65.2 |
Chilled | 45.1 | 65.6 |
Frozen | 34,6 | 52.0 |
Semen Type | Average litter size % vaginal insemination | Average litter size % transcervical insemination |
Fresh | 5.8 +/- 2.8 pups | 6.5 +/- pups |
Chilled | 5.8 +/- 3.0 pups | 6.4 +/- pups |
Frozen | 4.7 +/- 2.6 pups | 5.0 +/- pups |
Reference: Professor C. Linde –Forsberg. Intra-Uterine Insemination in the Dog Using the Scandinavian Trans-Cervical Catheter and a Comparison with other Methods. Sciences, Uppsala, Sweden. Publisher: Recent Advances in Small Animal Reproduction P. W. Concannon, G. England and J. Verstegen (Eds.). 02.02.2001. International Veterinary Information Service (www.ivis.org), Ithaca, New York, USA.
Semen extenders contain substances that help protect the semen cells.
Semen extenders contain a unique composition of conservation substances. There goal is to:
- Helps maintain the pH
- Provides a nutritional supplement for the sperm cells
- Helps prevent the growth of bacteria
- Helps protect the sperm cells against cold shock.
Semen extenders contain the following ingredients:
- Buffers to help protect the sperm cells against the temperature fluctuations during the freezing and thaw period
- Egg yolk and sugars which act as a nutritional supplement.
- Antibiotics and antioxidants
Canine semen is stored in 0.5 ml plastic straws which are resistant against deterioration from liquid nitrogen. Every straw contains the following information on it:
- Name of the stud dog
- Breed
- Registration number
- Date of sampling
- Veterinary clinic where the freezing process has taken place
It is advised per insemination with frozen semen to bring 150 x 106 “live” sperm cells directly into the uterus. Usually 3-4 straws are used per insemination.