Canine Reproductive Services

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Intermountain Pet Hospital's very own Dr. Vanderlip, who’s practice focuses on veterinary reproductive medicine and surgery for domestic and exotic mammals, including methods to improve animal health and fertility and eliminate genetic disorders.

We also employ an experienced technician who works with our vets. We freeze and store eggs and semen on site to ensure that your beloved pet's heritage isn't lost when he or she passes away.

Available Reproduction and Fertility Services

Intermountain offers a variety of services relating to animal reproduction and fertility. These include:

  • Vaginal Cytology
  • Animal semen freezing
  • Ovulation timing (for successful breeding)
  • High-risk pregnancy services
  • DNA swabs for American Kennel Club (AKC) testing
  • Infertility diagnosis and treatment
  • Consultation
    • Extended consultation and medical records review
    • Complete reproductive physical examination
    • Genetic testing and counseling
  • Artificial insemination
    • Transcervical insemination
    • Surgical insemination
    • Standard insemination with AI pipette/rod
  • Semen collection for
    • Artificial insemination
    • Analysis
    • Processing
    • Cooling and extending
    • Freezing and storage
    • Shipping
  • Reproductive surgery
  • Biopsies
    • Castration and cryptorchidectomy
    • Cesarean section
    • Embryo transfer
    • Follicle aspiration
    • Ovariohysterectomy
    • Surgical insemination
  • Ultrasound imaging
  • Neo-natal and peri-natal care
    • Vaccinations
    • Microchip implant for permanent identification
    • Nutritional guidance
  • Laboratory services include, but not limited to
    • Wellness blood panel (serum chemistries and CBC)
    • Cytology and histopathology
    • DNA tests
    • Brucella canis test
    • Leutinizing hormone test
    • Progesterone test
    • Relaxin test
    • Thyroid and other endocrine function
    • Cultures

Below are the forms needed to start the reproductions and fertility testing:

 

If there are any other tests you are interested in, please visit the Orthopedic Foundation for Animals website.

For clients with stud dogs

  1. Always bring a copy of the American Kennel Club registration (it has a purple border). We will need this to fill out AKC forms regarding semen freezing or inseminations. We will enter the AKC registration number into the computer, so the client only has to bring it to the first appointment.
  2. Always bring a copy of the DNA profile (it will have a V on it, followed by numbers), if available. AKC requires the sire to have a DNA profile on file with AKC in order to register puppies with AKC. If the owner hasn’t had a DNA profile done for the stud dog, we will take a DNA sample and submit the test at the time of the first visit, so this test would be included in the client estimate.
  3. Bring a copy of the most recent test results for Brucella canis. If a B. canis test hasn’t been performed in the past year, we need to repeat it. We require canis test for all dogs for which we are shipping or freezing semen. This test would be included on the estimate.
  4. Bring copies of all previous relevant medical records and breeding history available, to discuss with the doctor.
  5. Make a list of questions or concerns for the doctor to make the best use of the reproductive consult visit.
  6. If the stud dog is coming in for semen collection, ask the client to allow the dog to urinate immediately before leaving home to come to the clinic. A teaser female is not usually necessary, but if the client wants to bring one to the appointment, that is fine.
  7. If the stud dog is coming in for semen collection, ask the client what they plan to do with the semen today. Example: ship the semen, use it for an artificial insemination today, freeze the semen, or are they just verifying fertility and will be disposing of the semen?
  8. Make a list of diets, treats, supplements, and medications the stud dog is currently receiving.

For clients with females to breed

  1. Always bring a copy of the American Kennel Club registration (it has a purple border) to the first visit. We will need this to fill out AKC forms regarding inseminations and litter registrations. We will enter the AKC registration number into the computer, so the client only has to bring it to the first appointment.
  2. Bring a copy of the DNA profile, if available (it will have a V on it, followed by numbers). Not all females have a DNA profile. At this time, it is optional for females.
  3. Bring a copy of the most recent test results for Brucella canis, if available. A canis test is highly recommended for the female, but not required at this time.
  4. Bring copies of all previous relevant medical records and medical history available, to discuss with the doctor.
  5. Make a list of questions or concerns for the doctor to make the best use of the reproductive consult visit.
  6. Make a list of the animal’s breeding history, including dates of litters whelped, and dates of previous estrous cycles.
  7. If the female is coming in for ultrasound imaging for pregnancy diagnosis, ask the client to try to bring the animal in with a full urinary bladder and an empty gut to allow for best imaging.
  8. Make a list of diets, treats, supplements, and medications the female is currently receiving.

FREQUENTLY ASKED QUESTIONS

Should I breed my dog?

Dog breeding is an elective hobby. Breeding dogs and raising puppies is fun, but it is also a lot of hard work and responsibility. It can also be an expensive endeavor.

Dog breeding is not for everyone and not every dog should be bred. There are already too many homeless dogs in animal shelters. Many of these dogs have medical and behavior problems. The vast majority of them are mixed breeds. Many of these unfortunate animals are the result of indiscriminate mass breeding “for profit”. None of us want to add to the problem of homeless animals in shelters.

Ethical dog breeders always place their dogs’ health and best interests first. They learn all they can about their chosen breed and its standard. They test their dogs for any problems that may be inherited, before deciding to produce puppies from them. They are highly selective about the owners they choose for their puppies and make sure they go to excellent homes. Dog breeding, when done correctly, is rarely financially profitable.

Whether the future puppies are intended for performance, work, service, search and rescue, assisted therapy, field trials, agility, herding, or conformation in the show ring-the most important purposes of dog breeding are to help improve the breed overall and to produce healthy puppies for loving families. If you have a pure bred dog and these are your goals, Intermountain Pet Hospital would love to help you produce a beautiful litter of healthy, happy, quality puppies!

How do I know when the time is right to breed my dog?

Many years ago, we did not know exactly when to breed our dogs. We guessed breeding and gestation (pregnancy) dates based on when we noticed the first signs of pro-estrus. Then we counted the days in order to try to figure out the best time to breed our dogs, or estimate when they would deliver their puppies. As expected, this inaccurate method did not always work. Fortunately, the days of guessing are over!

At Intermountain Pet Hospital, we offer a variety of reproductive hormone tests that can help us accurately pinpoint the best time to breed or inseminate, when a litter is due, and when it is safe to perform a Caesarian section.

What reproductive hormone tests does Intermountain Pet Hospital offer in-house to accurately time inseminations and Caesarian sections?

The estrous cycle of the female is controlled by the interactions of changing levels of several reproductive hormones. Three important hormones–luteinizing hormone (LH), estrogen, and progesterone–play a major role in determining when, and if, ovulation (the release of eggs) occurs. These hormones and their interactions also cause observable signs of estrus (vaginal swelling, vaginal discharge, breeding behavior, and receptivity to the male). 

We offer tests for all of these hormones, with same day results for LH and progesterone. We also offer vaginal cytology and semen evaluations.

Leutinizing Hormone  (LH)

LH is normally present in very small quantities that fluctuate throughout the inter-estrous cycle.  During the estrous cycle a 20 to 40-fold increase of serum LH occurs rapidly over a 24-hour period and returns to baseline levels.  This rise in LH is called the "LH peak" and is responsible for triggering ovulation in the female.  The LH peak is the central event of the estrous cycle because it determines the time of ovulation and the best time to breed or inseminate.  By testing for the LH peak, we can determine the most fertile time period in the female, and therefore, the best days to breed or inseminate. We can also determine when the litter will be due, and the safest time to perform a Caesarian section. This time period is consistent, regardless of the age or breed of the female.

Only a small amount of blood is needed to run an LH test.

We offer LH testing with results available within an hour.

Progesterone

Progesterone is the hormone necessary for maintaining pregnancy to full term. Progesterone levels begin to rise on the same day as LH peaks.  Progesterone levels then continue to rise, until ovulation occurs, somewhere between 4 and 10 ng progesterone. After ovulation, canine eggs require an additional 2 to 3 days to mature, before they can be fertilized. There is no magic progesterone number used to time a mating. The rise in progesterone maintains pregnancy. It also may cause signs of false pregnancy in a non-pregnant female, regardless of whether or not the female has been bred. After ovulation, progesterone remains elevated in the female for two to three months. Progesterone levels decline gradually in a non-pregnant female, or drop abruptly prior to whelping in a pregnant female.

Progesterone testing is used to confirm that ovulation has occurred and that it is high enough to support pregnancy. Progesterone testing is also valuable to determine when it is safe to perform a Caesarian section.                

Only a small amount of blood is needed to run a progesterone test.

We offer progesterone testing with results available within an hour.

Estrogen

Estrogen levels rise slowly, beginning at the onset of proestrus, and continue to rise for 10-14 days, and then decline rapidly.  Peak estrogen levels usually occur several days before the LH peak.  Estrogens cause the observable signs of estrus (“heat”, “being in season”), such as vulvar swelling, bloody vaginal discharge, behavioral changes, and changes in vaginal epithelial cells.

When we do vaginal cytology on a female, we make a slide of the pet’s vaginal cells, stain them with a special dye, and look at them under the microscope. The changes we observe in the animal’s vaginal cytology give us general information about where she is in her estrous cycle. These changes are only a crude index and do not provide accurate information as to the ideal time for breeding.  However, vaginal cytology is valuable in telling us when it is too late to breed. In addition, if a mating has taken place within a few hours, sperm can be detected on the vaginal slide.

We offer vaginal cytology, with results available immediately.

How does ovulation relate to my dog’s “fertile window” or best time to breed?

Ovulation is induced by the LH peak, which causes the ovaries to release the developing eggs (ovacytes).  Ovulation occurs approximately 48-hours after the LH peak.  Canine eggs then undergo a subsequent maturation process which takes approximately 48-72 hours.  After this process, the eggs are capable of being fertilized and remain viable for an additional 24-72 hours.  This means that the fertile period of the female begins four days after the LH peak. Ideal breeding days are days 4-7 post-LH rise.

Because observable changes in vaginal discharge, swelling, and cytology can be observed from 3 to 10 days before the LH peak, hormone tests are the best method for accurately detecting the true fertile period in the female and determining the best time to breed.

Dog sperm cells (spermatocytes) may live sometimes live several days in the female’s reproductive tract. This means that the female may conceive, even if bred a few days prior to her fertile period.  However, if a mating or insemination takes place too early, this can result in lack of conception, or reduced litter size. 

When using fresh chilled extended semen, or frozen semen, the lifespan of the sperm cells is reduced and proper insemination timing becomes critical.  Accurate ovulation timing optimizes the chances of conception and enhances litter size.

If LH levels tell us the best time to breed, why do we test progesterone?

The rise in LH can be difficult to detect, because it usually only lasts for about a day before it drops. Daily LH testing can detect the LH rise, but can be expensive. Progesterone levels begin to rise on the same day as LH peaks. When progesterone is greater than 2 ng, the LH rise has already taken place. By running progesterone tests every other day, we can often determine the time of the LH rise, based on the progesterone value. We can also extrapolate the time of the LH rise by monitoring the pattern of the rise in progesterone.

Could you please summarize the role of the three main reproductive hormones in the female?

 

Three key hormones affect the estrous cycle of the female:

  1. Estrogens cause many of the signs of estrus, but ovulation cannot be timed based on estrogens. Estrogens affect vaginal cells, but vaginal cytology is only a crude index and should not be used exclusively to determine the best time to breed a female. However, vaginal cytology is a very useful tool in determining whether it is too late in the estrous cycle to breed a female. Vaginal cytology can also often detect whether a female has been bred within the past several hours.
  2. Leutinizing hormone (LH) is responsible for triggering ovulation. LH testing is used to accurately determine the fertile period in the female, the best time to inseminate, the true gestation period, and helps determine when the female will whelp (give birth).
  3. Progesterone is necessary to maintain pregnancy. The initial rise in progesterone occurs at the same time as the LH peak. Progesterone testing is necessary to determine if ovulation occurred. There is no specific progesterone level number for the “best time to breed”. Progesterone levels vary. It is the pattern of the progesterone rise that helps us determine the right time to breed.

Progesterone drops abruptly right before whelping and is responsible for the female’s drop-in temperature 12-24 hours before whelping.

Is it better to let my dogs breed naturally, or to do an artificial insemination (AI)?

Artificial insemination has many advantages over natural breeding (natural service).

It allows us to collect the semen and analyze it for quality. We can see if the sperm cell count is adequate to produce a pregnancy, if the sperm cells are normal in appearance, and if they have good motility. We can also check for signs of problems, such as blood, pus, bacteria, or urine (which is spermicidal) in the semen. With a natural breeding, we do not know if the semen quality was good.

Artificial insemination allows us to breed dogs safely. Some animals may fight during breeding, or be injured by splaying because they are unable to bear the weight of being mounted. Some dogs may have difficulty mounting or mating the female. Artificial insemination eliminates all of these problems.

Which gives the best results in conception rates and litter size: AI or natural breeding?

Artificial insemination often gives better results than natural breeding because semen quality is confirmed and the semen is delivered safely to the right place at the right time, without accident or injury.

What kinds of artificial insemination procedures does Intermountain Pet Hospital offer?

We offer standard insemination, using an inseminating pipette, and transcervical insemination (TCI), using an endoscope and video camera.

What is a standard insemination? 

A standard insemination can be performed using semen collected from the stud dog at the time of insemination, or using fresh-chilled extended semen shipped directly to us from the stud dog’s veterinarian. A standard insemination is performed using an inseminating pipette and the semen is deposited at the cervical os, which is the entry to the uterus. A camera is not used for this procedure.

What is transcervical insemination (TCI)?

Transcervical insemination (TCI) is a method of artificial insemination performed using a rigid endoscope and a video camera. The procedure can be observed in real time on a monitor. TCI allows for the passage of a catheter into the uterine body to enable semen deposition directly into the uterus. TCI is the inseminating method of choice when using frozen semen. It is also ideal for inseminating using fresh or fresh chilled extended semen.

What are the advantages of TCI over standard insemination or surgical insemination?

TCI allows the semen to be deposited directly inside of the uterine body, without the risks, discomfort, and expenses associated with surgery and anesthesia. TCI yields superior results to surgical insemination or standard insemination.

TCI is the preferred inseminating method when using frozen semen. It is also an excellent insemination procedure when using fresh chilled extended semen or freshly collected semen, or when using semen of less than ideal quality, or with poor motility.

Studies have shown that TCI is more successful than surgical insemination. TCI results in higher conception rates and larger litter sizes than surgical insemination does. TCI is performed without sedation and takes about 15 minutes, or less, to perform. Animals tolerate the procedure well. Unlike surgery, TCI can be performed multiple times during the same estrous cycle.

In some countries, including the UK, surgical insemination is now prohibited and obsolete, because it is considered unnecessary because TCI is a humane and superior option to surgery.

How is TCI performed?

The transcervical insemination procedure is accomplished by placing the female in a standing position on a lift table and raising the table to the ideal height for the size of the female and veterinarian performing the insemination. An exterior camera is attached to a rigid endoscope. The scope is then gently inserted and the vaginal vault, crenulation (vaginal folds), and cervical os (the opening to the uterus) are examined for health and to ensure that timing is accurate for insemination.

Are there different types of TCI equipment and techniques?

There are different types of rigid endoscopes and techniques that may be used to perform a TCI. One technique uses a narrow ureteroscope (9.5 French and 43 cm long), vaginal cuffs, insufflation, and a 5 mm rigid catheter that is threaded through the cervix in a twisting motion. Another technique, known as the New Zealand method, is the original method that was developed for TCI more than 30 years ago. It uses an extended length cystourethroscope (22 French and 29 cm long) and does not require a cuff or insufflation. It can accommodate all size females and uses an 8 French polypropylene catheter. The catheter is gently passed through the cervical os and into the uterus. For smaller females, a 6 French polypropylene catheter may be used.

Intermountain Pet Hospital uses both types of scopes and techniques for TCI. The scope used depends on the patient and the doctor’s preference.

For both types of endoscopes, semen is deposited directly into the uterus and the insemination is observed in real time on a monitor as far as the cervix. Beyond the cervix, the procedure is performed "blind" because after the catheter passes through the cervical os, it can no longer be seen by the camera.

How many inseminations are recommended?

Based on ovulation timing, we usually recommend two TCI procedures, 24-48 hours apart, to maximize chances of success.

Are there any risks associated with TCI or standard AI?

No artificial insemination procedure is without risk, whether it be TCI, surgical insemination, or standard insemination. There is a possibility of tissue trauma or puncture, but this is unlikely in the hands of a skilled veterinarian, unless the animal’s uterus is already compromised, abnormal, or diseased. This is one of the many reasons we conduct a thorough physical examination on all of our patients before we do any procedures.

Artificial insemination is not a sterile procedure. Although antibiotics may be added to canine semen, bacteria and other organisms may still be present in the semen, as well as in the vagina. Increased prolonged progesterone levels after ovulation may contribute to making the canine uterus more susceptible to infection, so we conduct a thorough physical examination on every patient and take great care when performing all reproductive procedures.

How do I schedule my dogs for artificial insemination?

All patients must be examined to ensure that they are healthy, before we can do an artificial insemination or semen collection. Please call us at (208) 888-2910 to schedule an appointment in advance of the anticipated inseminating date, or at the very earliest signs of estrus. A physical examination of our patients prior to doing any procedure allows us to make the best recommendations for each animal’s current health status and helps us optimize our clients’ chances of a successful outcome. A patient examination also ensures compliance with the Idaho Veterinary Practice Act.

When we examine your pet for breeding, we verify that the male and female are fertile and free of contagious diseases, including venereal diseases. We make sure that the females are healthy enough to tolerate the significant stresses and demands of pregnancy. All pet owners are provided an extensive consultation and question and answer period at the time of their animals’ examinations.

What is the difference between fresh semen, fresh chilled extended semen, and frozen semen?

Fresh semen is semen that has been collected for immediate insemination.

Fresh chilled extended is semen that has been collected for overnight shipment to a destination to be used for insemination. An extender is a special nutrient liquid added to the sperm cells to keep them alive during cooling and transport. The sperm cells are then shipped overnight in special packaging with ice packs to be used for insemination within 1-2 days.

Frozen semen is semen that has been specially processed with a cryoprotectant formula and frozen in liquid nitrogen. The semen must remain stored in liquid nitrogen. It cannot be stored in a regular freezer. Once in liquid nitrogen, the semen can be preserved indefinitely, as long as the storage tank is kept filled with liquid nitrogen. Shipping frozen semen requires a special shipping tank that holds liquid nitrogen and keeps the semen frozen until it reaches its destination. Once it is thawed, frozen semen must be used immediately. It cannot be refrigerated or refrozen. Frozen semen does not live as long in the female’s reproductive tract as fresh and fresh chilled extended semen does. Frozen semen requires transcervical insemination (TCI) technique.

Semen Freezing and Storage Services

If you would like to have your dog’s semen collected, analyzed, frozen, and stored for future use, please call us at 1 (208) 888-2910 to schedule a semen freezing appointment.

What is involved in semen collection and freezing?

The semen collection process is painless and will be a positive experience for your dog. No sedation is used. The procedure usually takes about fifteen minutes to complete, but if your dog is inexperienced, collection time may take longer. A female in estrus (in season/in heat) is not necessary to collect a dog, but if you have one available, we recommend that you bring her to help encourage your dog, especially if he is inexperienced.

You can take your dog home immediately after the collection is completed. We will call you later the same day with the number of inseminating doses obtained from the collection.

Your dog’s semen will be processed and frozen in pellets. After it is frozen, one pellet is thawed and tested to ensure that the post-thaw semen quality is satisfactory. The frozen semen pellets are then packaged into individual inseminating doses, based on your dog’s sperm count, sperm morphology, and post-thaw motility. The number of inseminating doses that each dog produces varies and is dependent on the animal’s health, age, breed, and other factors.

What to bring to your dog’s semen freezing appointment

The following documents and tests are required at the time of semen freezing.

  1. A copy of your dog’s American Kennel Club (AKC) registration (it has a purple border). We need this to fill out the AKC semen collection report form and to put all identifying information on the cryovials that contain your dog’s frozen semen. We will scan a copy of your dog’s AKC registration into the computer, so you only have to bring this document to your dog’s first appointment.
  2. A copy of your dog’s AKC DNA profile (it will have a V on it, followed by six numbers). AKC requires all sires to have a DNA profile on file with AKC in order to register puppies with the AKC that were produced from frozen semen. If you do not yet have a DNA profile for your dog, we will take a DNA sample and submit the test at the time of your dog’s first semen freezing visit. This is a one time test that is submitted to the AKC along with the semen collection report.
  3. A copy of your dog’s most recent test results for Brucella canis. If a Brucella canis test has not been performed within the past month, we will do one at the time of semen collection. canis is a serious transmissible disease and there is no cure for it. In order to protect our clients’ dogs, we require a B. canis test for all dogs for which we are freezing or shipping semen.
  4. Your dog’s microchip number. We will scan your dog to make sure his microchip is still in place and working. If your dog does not yet have a microchip, we highly recommend having him microchipped. We are happy to provide this service for you.
  5. We will provide you with a Semen Freezing Authorization form to fill out at your appointment.

The fee for semen freezing includes your dog’s physical examination, semen collection, full semen analysis, processing, materials, post-thaw test, documents, file preparation, and first year’s storage fee for up to four inseminating doses. Each inseminating dose is stored in an individual cryovial. If your dog produces more than four inseminating doses, you may elect to keep the additional doses for an additional processing fee.

Fees not included in the semen freezing are for the B. canis test, DNA profile for AKC (if applicable), and microchip.

Where is my dog’s frozen semen stored?

Your dog’s frozen semen is stored on location at Intermountain Pet Hospital, in our liquid nitrogen storage tanks. It will be immediately available whenever you want to use it or ship it.

What is canine brucellosis? Is it serious?

Canine brucellosis is a contagious disease caused by Brucella canis. In the dog, canine brucellosis can cause infertility, embryonic death, abortions, testicular atrophy, epididymitis, scrotal dermatitis, and lymphadenitis. Other tissues besides reproductive organs may become infected, including the kidneys, eyes, intervertebral disks, and meninges. Some dogs may show no symptoms other than infertility. Canine brucellosis is spread through direct contact with infected tissues, vaginal discharge, mammary secretions, urine, saliva, nasal secretions, and semen.  It can be contracted through contact with mucosal surfaces, by ingestion, or by mating.

There is no cure for canine brucellosis. It is a reportable disease that has been found in dogs throughout the United States. It can devastate a breeding program and kennels, because neutering does not prevent the spread of the disease and it can be transmitted in a variety of ways besides mating.

Brucella canis can be spread to humans. Some of the symptoms in humans include fever, sweats, weakness, headaches, and enlarged spleen and lymph nodes.

Is there a test for canine brucellosis?

Canine brucellosis is a serious, contagious disease for which there is no cure.

Intermountain Pet Hospital offers a blood test for B. canis. Results are available within 30 minutes.

We highly recommend a B. canis test for all canine natural matings, as well as all artificial inseminations.

For the safety of our patients and our clients, and to prevent the possible spread of a serious and incurable disease, we require a B. canis test for all dogs for which we are shipping or freezing semen.

How do I know when the time is right to breed my dog?

Not long ago, we did not know have many tests available to help us determine the best time to breed our dogs. We guessed breeding and gestation (pregnancy) dates based on when we noticed the first signs of pro-estrus. Not surprisingly, this inaccurate method did not always work. Fortunately, our days of guessing are over!

At Intermountain Pet Hospital, we offer a variety of reproductive hormone tests that can help us accurately pinpoint the best time to breed or inseminate, when a litter is due, and when it is safe to perform a Caesarian section.

What reproductive hormone tests does Intermountain Pet Hospital offer in-house to accurately time inseminations and Caesarian sections?

The estrous cycle of the female is controlled by the interactions of changing levels of several reproductive hormones. Three important hormones–luteinizing hormone (LH), estrogen, and progesterone–play a major role in determining when, and if, ovulation (the release of eggs) occurs. These hormones and their interactions also cause observable signs of estrus (vaginal swelling, vaginal discharge, breeding behavior, and receptivity to the male). 

We offer tests for all of these hormones, with same day results for LH and progesterone.  

Leutinizing Hormone  (LH)

LH is normally present in very small quantities that fluctuate throughout the inter-estrous cycle.  During the estrous cycle a 20 to 40 fold increase of serum LH occurs rapidly over a 24 hour period and returns to baseline levels.  This rise in LH is called the "LH peak" and is responsible for triggering ovulation in the female.  The LH peak is the central event of the estrous cycle because it determines the time of ovulation and the best time to breed or inseminate.  By testing for the LH peak, we can determine the most fertile time period in the female, and therefore, the best days to breed or inseminate, which is 4 to 6 days after the LH rise. We can also determine when the litter will be due, and the safest time to perform a Caesarian section. This time period is consistent, regardless of the age or breed of the female.

We offer LH testing with results available within an hour.

Progesterone

Progesterone is the hormone necessary for maintaining pregnancy to full term. Progesterone levels begin to rise on the same day as LH peaks.  Progesterone levels then continue to rise, until ovulation occurs, somewhere between 4 and 10 ng progesterone. After ovulation, canine eggs require an additional 2 to 3 days to mature, before they can be fertilized. There is no magic progesterone number used to time a mating. The rise in progesterone maintains pregnancy. It also may cause signs of false pregnancy in a non-pregnant female, regardless of whether or not the female has been bred. After ovulation, progesterone remains elevated in the female for two to three months. Progesterone levels decline gradually in a non-pregnant female, or drop abruptly prior to whelping in a pregnant female.

Progesterone testing is used to confirm that ovulation has occurred and that it is high enough to support pregnancy. Progesterone testing is also valuable to determine when it is safe to perform a Caesarian section.                

We offer progesterone testing with results available within an hour.

Estrogen

Estrogen levels rise slowly, beginning at the onset of proestrus, and continue to rise for 10-14 days, and then decline rapidly.  Peak estrogen levels usually occur several days before the LH peak.  Estrogens cause the observable signs of estrus (“heat”, “being in season”), such as vulvar swelling, bloody vaginal discharge, behavioral changes, and changes in vaginal epithelial cells.

When we do vaginal cytology on a female, we make a slide of the pet’s vaginal cells, stain them with a special dye, and look at them under the microscope. The changes we observe in the animal’s vaginal cytology give us general information about where she is in her estrous cycle. These changes are only a crude index and do not provide accurate information as to the ideal time for breeding.  However, vaginal cytology is valuable in telling us when it is too late to breed. In addition, if a mating has taken place within a few hours, sperm can be detected on the vaginal slide.

We offer vaginal cytology, with results available immediately.

How does ovulation relate to my dog’s “fertile window” or best time to breed?

Ovulation is induced by the LH peak, which causes the ovaries to release the developing eggs (ovacytes).  Ovulation occurs approximately 48 hours after the LH peak.  Canine eggs then undergo a subsequent maturation process which takes approximately 48-72 hours.  After this process, the eggs are capable of being fertilized and remain viable for an additional 24-72 hours.  This means that the fertile period of the female begins four days after the LH peak. Ideal breeding days are days 4-7 post-LH rise.

Because observable changes in vaginal discharge, swelling, and cytology can be observed from 3 to 10 days before the LH peak, hormone tests are the best method for accurately detecting the true fertile period in the female and determining the best time to breed.

Dog sperm cells (spermatocytes) may live five to seven days in the female’s reproductive tract. This means that the female may conceive, even if bred a few days prior to her fertile period.  Matings that occur several days before the fertile period can result in lack of conception, or reduced litter size, because few sperm cells remain viable when the eggs are mature enough to be fertilized. 

When using fresh chilled extended semen, or frozen semen, the lifespan of the sperm cells is reduced and proper insemination timing becomes critical.  Accurate ovulation timing optimizes the chances of conception and enhances litter size.

If LH levels tell us the best time to breed, why do we test progesterone?

The rise in LH can be difficult to detect, because it usually only lasts for about a day before it drops. Daily LH testing can detect the LH rise, but can be expensive. Progesterone levels begin to rise on the same day as LH peaks. When progesterone is at 2 ng, the LH rise has already taken place. By running progesterone tests every other day, we can often determine the time of LH rise, based on the progesterone value. We can also extrapolate the time of the LH rise by monitoring the pattern of the rise in progesterone.

Could you please summarize the role of the three main reproductive hormones in the female?

Three key hormones affect the estrous cycle of the female:

  1. Estrogens cause many of the signs of estrus, but ovulation cannot be timed based on estrogens. Estrogens affect vaginal cells, but vaginal cytology is only a crude index and should not be used exclusively to determine the best time to breed a female. However, vaginal cytology is a very useful tool in determining whether it is too late in the estrous cycle to breed a female. Vaginal cytology can also often detect whether a female has been bred within the past several hours.
  2. Leutinizing hormone (LH) is responsible for triggering ovulation. LH testing is used to accurately determine the fertile period in the female, the best time to inseminate, the true gestation period, and helps determine when the female will whelp (give birth).
  3. Progesterone is necessary to maintain pregnancy. The initial rise in progesterone occurs at the same time as the LH peak. Progesterone testing is necessary to determine if ovulation occurred. There is no specific progesterone level number for the “best time to breed”. Progesterone levels vary. It is the pattern of the progesterone rise that helps us determine the right time to breed.

Progesterone drops abruptly right before whelping and is responsible for the female’s drop in temperature 12-24 hours before whelping.

How soon can I ultrasound my dog to find out if she is pregnant?

Pregnancy in the canine can be detected on ultrasound as early as 19 days after conception. To detect fetal heartbeats, it is better to wait at least 22 days after conception. We recommend waiting 30 days after breeding or insemination, to be sure that we can definitely confirm pregnancy.

I want to know how many puppies my dog is going to have. How soon can I have radiographs done?

Fetus are not visible on x-ray until their bones are mineralized enough to be detected. For this reason, we recommend waiting at least 45 days post breeding before having a radiographs performed on your pet.

My dog has been showing signs of distress and labor, but has not delivered a puppy. When should I be concerned and bring her in for an exam?

If you have any questions or concerns about your pet and her pregnancy, call us immediately. Every case is different. If your dog has been in hard labor for over an hour, without producing a puppy, call us. If she is passing blood, amniotic fluid, or has a green discharge and has not delivered a puppy, call us. It may be possible that she needs a Caesarean section, or that her puppies may need to be checked by ultrasound to see if they are in distress.

I want to do the right health tests and genetic tests for my dog. How do I know which tests my dog needs?

Any dog can be a carrier of one or more genetic conditions. Some breeds are more predisposed to certain conditions than others. Depending on your dog’s breed, age, and health, we can guide you in which tests are most important. We can assist you in certifying your dog through the Canine Health Information Center (CHIC), working together with the American Kennel Club and the Orthopedic Foundation for Animals (OFA).

At Intermountain Pet Hospital, we can also help you become part of the American Kennel Club’s “Bred with H.E.A.R.T” program.  (H.E.A.R.T. stands for Health, Education, Accountability, Responsibility, and Tradition). We can guide you though the health testing recommendations for your breed, based on the recommendations of your breed’s respective Parent Club as documented in their Code of Ethics or in the OFA’s CHIC.