On February 27, 2014, the following interview was first made available as a podcast. This is an abbreviated transcript. Dr. Please listen to the podcast that Schultz recorded so that you can learn more about what he has to say.
Dr. After graduating from Michigan State University with a DVM in 1973, William Schultz entered private practice and launched his companion animal clinic in the fall of 1974. Dr. Theriogenology expert Schultz is a well-known speaker at veterinary conferences, veterinary associations, and national specialties. He is a member of The Society for Theriogenology and The Theriogenology Foundation. Dr. On transcervical and surgical inseminations using fresh, chilled, and frozen semen, Schultz has delivered lectures and written articles.
This podcast is a special canine reproduction series produced in collaboration with our business partner, Zoetis.
Let’s discuss canine artificial insemination and ovulation timing in general, according to the AKC Canine Health Foundation (CHF). When, in your opinion, do breeders benefit from them the most?
DR. Although artificial insemination has been practiced for a long time, William Schultz says that the ability to freeze, chill, and ship semen has significantly changed how successfully planned breedings can be carried out. For many kennels, vaginal, transcervical, and surgical inseminations are now standard practice. Progesterone testing and serum LH, or leuteotrophic hormone, have replaced semi-quantitative vaginal cytology as the gold standards for ovulation timing. Later in the podcast, we’ll talk about testing and breeding techniques. The benefits to breeders are nothing short of incredible. Almost anywhere in the world can now successfully produce fertile offspring through semen exchange. The stress associated with traveling and waiting for the bitch to stand and breed while in a foreign environment is reduced because the bitch doesn’t need to leave the house to be bred. Given the high cost of travel today, staying at home has financial advantages for the breeder as well. Stress from travel can reduce conception.
CHF: The collection of semen used in artificial insemination is a good place to start this discussion. What should the surroundings be like and what supplies should you have available for collecting semen from a stud dog?
Schultz: We gather in the same exam room at our clinic so that the student is accustomed to it. In this room, no vaccinations or other procedures involving studs are performed. We also have a breeding rug. This rug only requires occasional washing and has a rubber backing for non-slip footing. The stud is brought into the space and given some time to settle in and look around. Smaller breeds are gathered on the examination table, while large breeds are gathered on the floor. To ensure slip-resistant surfaces, the rug is moved to the table. Because the room is not in the middle of anything, it can be quieter. The collection area in a kennel should be as isolated as possible; occasionally, a calm store room area can be used. Avoiding as many outside distractions as possible will always be beneficial. We use a disposable artificial vagina for the collection. These have a cone-shaped end that has been cut off to accommodate a 15 ml centrifuge tube. To separate the semen fractions during collection, the tubes may be swapped out. The cone’s wide end can be folded to the outside to change the length to fit stud dogs of various sizes. Lubricants are not needed. This approach outperforms gathering in a baggie by a wide margin. The studs are significantly more receptive to an entire collection and the cone will fit snugly stimulating a tie. It’s crucial to have a teaser bitch, and in some cases, she might need to be fully standing heat. Without a standing teaser, we have seen inexperienced males refuse to release sperm rich fractions. This may lead to an incorrect diagnosis of infertility. Avoid wearing white coats, act relaxed, friendly, and non-threatening. Depending on what the stud is used for, the collection may be done on the ground or on a table. Ask the owner to bring any specifics, such as a rug or breeding rack, that the stud associates with breeding. All equipment must be at room temperature.
CHF: Is there anything else you can do if you don’t have access to a female in heat? Why do you need a teaser bitch in the room?
Shultz: The ease of collection and collection volume will almost always be significantly increased by the teaser. The insemination is completed by a single sperm, but it requires millions to billions of sperm to get there. In the absence of a teaser, we use swabs from previous bitches’ vaginal cytology. We allow the male to sniff the swabs while they are kept in a baggie in the refrigerator. These swabs might be frozen, but we’ve found that the fridge works just fine, and we swap out swabs every month. Swabs can be applied near a bitch’s anal and vulvar area to simulate a bitch in heat if the bitch is not currently in heat. The non-cycling bitch needs to be closely monitored because if a man tries to mount her, she might become very hostile. If swabs and a teaser are unavailable, Zoetis’ synthetic pheromone Eau d’Estrus may be useful. Have an estrus teaser bitch that is roughly the same size as the stud dog available, if at all possible. Bring the bitch into the room. The bitch should be supported in a standing position by a handler or technician who can also restrain her if necessary. Use an anestrous bitch restrained in a standing position if that isn’t possible. Some vaginal secretions taken during estrus should be kept frozen. These can be defrosted by dipping them in warm water, and then you can wipe them on a teaser that isn’t in season. A good teaser will frequently release 30–50% more sperm cells. Despite the fact that many dogs may have their semen collected without a teaser bitch, the quality of the semen is typically better when the teaser bitch is in estrus and the stud’s libido is at its highest. A pheromone like Eau d’ Estrus is an alternative training tool.
CHF: Is there anything that needs to be done prior to bringing a dog into the room to collect semen?
Before the collection, Shultz advises taking the male for a walk and letting him use the restroom. If possible, this should be carried out entirely outside of the teaser.
Shultz: Once more, the male is given time to get used to the teaser and interact with her before any attempts are made to collect. To lessen the level of distraction, there should be as few owners and assistants present as possible. A good stud dog, however, won’t care as long as there is a teaser around.
Make the stud dog as comfortable as you can when conducting semen collections.
Shultz: Put the bitch in place and enter the room with the stud. Give him time to get comfortable with his surroundings, the bitch, and you.
Be careful at this time not to quickly mount and tie the bitch if the teaser is not to be bred.
While the stud is permitted to mount the bitch, I am seated in a low chair to allow for quick movement. Being just to the side of the stud will enable movement of the stud while keeping you close enough to perform the collection using the artificial vagina. When collecting, it’s crucial to leave enough space for the stud to mount and then dismount.
Allow the male to mount. Gently massage the preputial sheath with one hand as he starts to thrust. You can massage the sheath to induce an erection if the guy isn’t interested in the girl and doesn’t mount.
As erection occurs, pull the sheath behind the bulbus glandis. Likewise, with the other hand, place the AV just below the bulbus glandis over the penis.
Be careful that the male does not have an engorged bulbus glandis when reflecting the sheath. After the bulbus glandis has engorged, reflecting the sheath is extremely painful, if not impossible. If necessary, the male may be led outside and walked until the bulbus glandis has subsided before another attempt at collection is made. It might be necessary to collect the sample from some extremely aggressive studs while the sheath is partially covering the bulbus glandis.
Put your hands in a new position, applying gentle pressure that is consistent and close to the bulbus glandis. With your other hand, you can stimulate the penis that is closest to the bulbus glandis.
Most dogs will thrust initially, coinciding with the penetration. They will attempt to step over the bitch and your arm once they reach full erection, which coincides with the “tie.” The stud can benefit from your assistance if you lift his leg over your arm and turn his penis 180 degrees so that it points backwards between his legs.
The semen should be visible as it flows into the transparent tube. An initial clear or slightly cloudy pre-ejaculate fraction, the sperm-rich fraction (SRF), and a clear fraction of prostatic fluid make up the majority of dogs’ ejaculates. During the period of vigorous thrusting, the initial clear fraction is released. The SRF should release as a viscous, creamy, white liquid as soon as the stud stops thrusting vigorously and steps over. The SRF may be thin and white and the volume may range from 1/2 cc to 10 cc in some studs. The clear prostatic fluid follows in varying amounts. The collection is stopped once the SRF has been released and the first prostatic fluid is detected. (Violent thrusting may not be seen if a teaser bitch is not used. ).
During collection, switch the tubes attached to the artificial vagina to separate the fractions. Pre-ejaculate and SRF won’t be separated until the centrifugation process because I centrifuge all samples. It is crucial to separate the fractions if there is no centrifuge available. The contents of tubes that were changed too soon may be combined, if necessary, following microscopic analysis. Make sure you have collected the entire SRF before stopping. The third fraction does not have to be collected in full; just enough should be saved to check for abnormal cells, bacteria, etc.
Making sure the erection has passed after the collection is crucial. The male is never permitted outside on chilly days when the erection is present because frostbite is possible in the winter. The time it takes to lose the erection will be shorter if you walk the stud after the collection. You can use a sterile lubricant now if the penis seems dry. Before putting the dog in a cage or around other dogs, make sure the penis is completely retracted into the sheath.
Shultz: Fresh semen can be extended with Fresh Express Extender (Zoetis) and centrifuged with Semen Separating Solution (Zoetis) if it won’t be used for a few days. Labeled and placed in a beaker with water and a 40 degree farenheight refrigerator, the extended semen is harvested. If the refrigerator door is opened, the water bath’s goal is to prevent the sample from rapidly warming and cooling. While most refrigerators turn on and off with a 5 to 8 degree temperature variation, our refrigerator is kept at a constant 40 degrees. We have successfully kept semen for a breeding for over three weeks by using this technique. To maintain the highest level of motility possible, the semen is examined every two to three days, and the extender is changed as needed.
CHF: Let’s turn our attention to the bitch. Can you explain to breeders the phases of the estrus cycle and the main hormones that control the cycle?
Proestrus: This is the initial stage of the heat cycle. Proestrus will last 8 to 11 days in most bitches. Vaginal bleeding starts during this period. In order to prepare for reproduction, estrogen is secreted, which causes vaginal dilation and thickening of the vaginal walls as well as the initial attraction of males. During this stage the eggs are developing on the ovaries. The eggs are in a fluid sac called a follicle. These appear as the buck approaches estrus and have a diameter of about a half-centimeter. At this point, we have examined the ovaries, and in many cases, we can predict how many eggs the bitch will release during estrus.
Estrus: This is the breeding portion of the cycle. This is also called Standing Heat. This stage lasts 3 to 6 days. The bitch will stand and flag for the men now that she is open to them. Estrus causes the bitch’s estrogen levels to drop quickly and her progesterone levels to rise. At the locations of the follicles, the ovaries secrete progesterone. When the pituitary gland secretes LH (leuteotrophic hormone), the follicles burst.
Diestrus: All canines enter a diestrus phase when standing heat ends. For the duration of pregnancy, the ovaries secrete progesterone. Regardless of whether the b*tch is pregnant, progesterone is secreted. Because of this, human tests on dogs are ineffective. Humans only secrete progesterone if pregnant. The uterus-placenta interface releases the hormone known as relaxin. This hormone rises quickly and can be used as a dog pregnancy test. The test is offered by Zoetis and can be used 20 days after breeding, but 30 days provides the highest accuracy.
Anestrus: this is the recovery phase. Anestrus has very little hormone function present. The uterus is healing during this stage, which typically lasts four months.
There are numerous diagnostic and auxiliary tools available to help with timing ovulation and subsequent inseminations in the chubby No single test or assay is 100% accurate or 100% correlated with the exact estrus stage of the buck. A single exam, vaginal smear, assay result, etc. , provides very limited information. When multiple parameters are repeatedly assessed, ovulation timing is more accurate and breeding management is more successful. Useful aids utilized in practice to time breedings include:
Evaluation of the vaginal tract’s surface cells is known as vaginal cytology. The vaginal lining thickens significantly during the heat cycle to protect the tract during breeding. Dogs don’t require the thicker walls outside of estrus, when breeding only occurs. Small, rounded cells with a large nucleus called parabasals are replaced by superficial cornified cells, which can be large cells that resemble cornflakes.
In the past, timing with vaginal swabs was the only method available for breeding, but today we have access to many more precise tests to identify the breeding day or days.
Utilizing a q-tip that has been moistened with saline for vaginal cytology The swab is passed dorsally after being inserted in the vaginal vault. It is then rubbed on the vaginal wall and removed. The cells are transferred by rolling the swab on a slide. The slide is then stained for examination of the cells. When deciding when to breed the bitch, this method performs well for determining the stage of the cycle but poorly for other purposes.
The vaginal cells transition from superficial cells to parabasal cells to intermediate cells. The nucleus shrinks or disappears, the outer cell wall becomes irregular, and tiny holes appear in the cell body, which causes the superficial cells to cornify and take on the appearance of cornflakes. Most heifers’ cornification occurs during the estrus stage, but in a few, it may occur very early in the cycle and last for several days.
The end of the heat cycle or the first day of diestrus can both be accurately predicted using vaginal cytology. A mixture of parabasals, intermediates, cornified cells, and white blood cells appear in the cytology within 24 hours, as opposed to the majority of cornified cells.
A type of endoscope is used during a procedure known as a “vaginoscopy” to examine the cranial vaginal area. During the heating cycle, the vagina’s surface transforms from a smooth, shiny surface to a thickened tissue with deep folds and a surface with numerous, minute wrinkles. This is rarely used today because we have very accurate progesterone timing.
This is a simple counter top assay from Zoetis. The actual identification of the LH surge through direct measurement of canine LH levels is the ovulation timing parameter that is the most precise. To estimate the fertile period more precisely, this method is advised.
Shultz: We are aware that no test can accurately predict ovulation. Utilize as many diagnostic tools as possible. Very little information can be obtained from a single vaginal smear, one LH or progesterone value, or one vaginoscopic examination.
Shultz advises counting ahead to the fertile period after identifying the LH surge. Day 0 refers to the day of the LH surge. The true fertile period lasts from days 4 to 7 after the LH surge, with days 5 and 6 being the most fertile. After the Progesterone rise or LH surge, we perform transcervical or vaginal breedings on days 3 and 5, with frozen semen breedings on day 5. Depending on the reproductive veterinarian being used, breeding dates may change. By carefully organizing inseminations, the likelihood of successful fertilization is maximized.
Enroll in a clinical trial or donate samples to help with research on canine health. Dogs in both the healthy and diseased states must provide samples.
The Quantity of Sperm that a Dog Produces
Normal dog semen contains 300 million to 2 billion sperm. The quantity of sperm varies depending on the weight and size of your dog, with the bare minimum sitting at around 10 million sperm cells per pound of bodyweight. For example, a 30-pound dog should have at least 300 million sperm cells in his ejaculate. A 60-pound dog should have 600 million sperm cells in his ejaculate. Sperm count also depends on your dog’s testicular size. Most normal dogs exceed the minimum count significantly. In normal sperm production in dogs, more than 70% of the sperm are progressively motile and normal morphologically.
The average volume of dogejaculate ranges anywhere from 1 to 30 mL. Dog semen is produced in three fractions. The first fraction is small in volume at less than 5 mL. It cleanses the urethra of any contaminants before ejaculation. The second fraction is rich in sperm and usually 0.5 to 4 mL in volume. The third and final fraction contains prostatic fluid and few sperm cells. This final fraction lends more volume (3 – 80 mL) to the ejaculate. Volume is not a reliable indicator of semen quality. Instead, it’s measured to find the concentration of sperm in the ejaculate.
Storing dog sperm has drastically changed breeders’ ability to carry out planned breedings with success. Vaginal and transcervical insemination is the new norm for many breeders, and it is possible to breed using semen from dogs anywhere in the world, reducing travel costs for breeders and stress for the dogs. Storage is a great way to preserve bloodlines for future use, especially in cases where the stud is due to be neutered. Finally, storing dog sperm is a great way to ensure that breedings can continue when your dog is on a busy schedule or otherwise unable to perform stud work due to factors like temporary illness or injury.
Sperm storage facilities are widely available. Once you have found a facility that suits your location and needs, make an appointment with the facility. You will need to transport yourself and your dog to the location. Make sure that you bring any relevant registration certificates (AKC, UKC, or other applicable registries), a DNA profile number, and a copy of your negative brucellosis test within the last 6 months. It is also helpful to bring a “teaser” bitch (in heat) with you. This helps to increase your male dog’s libido and encourages a 30-50% higher sperm count.
Your dog’s semen sample is extended with a buffer solution to protect the sperm cells during freezing. After a sperm count is performed, the sample is further diluted to make up a uniform concentration. The diluted sample is divided into individual straws – the number of straws is decided through the initial sperm count. These straws are stored in liquid nitrogen at a constant -196 degrees Celsius. After the cooling and freezing process, one straw is thawed and thee sperm is examined for motility. The average post-thaw motility rate is 40-60%, meaning that 40-60% of the sperm cells survive the thawing process. This information is also used to determine the amount of semen you will need for insemination.
Online advertisements for stud dogs’ one-to-one mating, chilled, and frozen sperm services are common. Depending on the stud’s heritage and pedigree, a one-to-one mating session typically costs between $500 and $1,000 in stud fees. In the event that the owner of the stud is required to help with the mating, there may also be a handling fee. In a similar vein, the price of chilled or frozen semen differs according to the stud’s lineage. Due to this, the stud’s owner usually provides the cost of the stud’s semen upon request.
You may dispatch your stud’s chilled semen by using a specialized kit. There are many successful chilled semen kits commercially available. The CLONE Chilled Semen Kit has been successfully used for over 25 years, especially in North America. No special training is required as the kit comes with instructions and equipment. Alternatively, some veterinarians offer chilled semen kits and may be able to assist with the process. If in doubt, ask for referrals from other local breeders!
You should think about the morality of selling your dog’s sperm before doing so. It’s imperative that you look into general DNA testing and have your dog tested for inherited diseases that are known to affect their breed. Additionally, you ought to refrain from taking too many sperm from your dog. Although sperm production is constant in dogs, taking too much can lower sperm counts and lower the quality of semen.
How many times does a dog have to mate to get pregnant?
The majority of dogs breed for the first time between days 10 and 14 after proestrus begins. The general consensus is that two or three matings, every other day, are sufficient as long as the bitch will accept the male.
How much sperm is needed to AI a dog?
Sperm counts of more than 200 million are typically observed in rested stud dogs. Reliable vaginal artificial insemination requires counts of at least 200 million motile sperm. The quantity of sperm that can move forward determines viability.
FAQ
How successful is dog insemination?
With fresh semen, AI in dogs has the highest success rate. The success rate varies depending on the breeder’s skill but resembles natural breeding when the female dog is immediately inseminated. The success rate falls to between 59 and 80 percent when using fresh, chilled semen.
How long does it take a male dog to build up sperm?
A new sperm cell is produced in the body after 60 days, and it matures after another two weeks. After a period of sexual rest, the first two collections are typically the most excellent. Each breeding technique used must demonstrate stud dogs.
How much sperm do dogs release?
There are 300 million to 2 billion sperm in a normal dog’s ejaculate, which ranges in volume from 1 to 30 mL and contains more than 70% progressively motile, morphologically normal sperm.
How strong is dog sperm?
Most fertile dogs’ sperm have a motility of 90 to 95% in their semen. Motility levels below 80% may be a sign of decreased fertility.