I decided to do some research to better understand the processes when using frozen semen for breeding. One of the first articles I read, to understand this better was about ovulation and LH testing. I put together a short summary of what I found. I am at no means an expert in this field, however, I do think it will also help someone else. I do want to thank Shelby who told me about this when using frozen semen and breeding to determine with right time when using frozen semen.
Below is a short summary I put together of my findings, anyone who can add more information, please do so.
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In dog breeding, determining the optimal time for mating female dogs can be challenging, especially in Boerboels. Progesterone and LH testing are commonly used tools to aid breeders in this process, especially in frozen semen. Progesterone testing helps identify when a female dog is ovulating, increasing the chances of successful breeding and larger litters. It can also predict delivery dates, diagnose cycle abnormalities. LH testing, when used in conjunction with progesterone testing, assists in pinpointing ovulation time accurately. While LH testing alone may not be as effective, combining it with progesterone testing confirms ovulation. Both tests involve drawing a blood sample from the female dog for analysis and provide numerical results. These tests are crucial for predicting fertility, diagnosing ovarian tumors, and ensuring successful breeding outcomes. By monitoring hormonal changes like estrogen, LH, and progesterone, breeders can optimize the breeding process and ensure the health and well-being of their dogs.
Estrogen plays a crucial role in a bitch’s proestrus stage, with various types such as estrone, estradiol, and estriol being produced to facilitate sexual development and physical changes during her heat cycle. Estradiol, in particular, stimulates womb lining growth and ovulation after reaching peak levels. Luteinizing hormone (LH) works with follicle-stimulating hormone (FSH) and estradiol to trigger ovulation, with a surge lasting 24 to 48 hours. The LH surge signals the release of eggs, and testing for this hormone can help predict ovulation. Progesterone levels also increase during this time to prepare the bitch for pregnancy by supporting blood vessel growth in the womb lining and facilitating egg implantation. Physical and behavioral changes, such as vulval swelling, discharge, and mating readiness, accompany the LH surge, allowing veterinarians to pinpoint ovulation through hormone testing. Overall, the interplay of estrogen, LH, and progesterone orchestrates the reproductive cycle in female dogs.
During your bitch’s heat cycle, she may exhibit breeding behaviors such as changes in appetite, increased urination to attract male dogs, and changes in behavior such as agitation or affection. Progesterone testing should begin 3 to 5 days into the heat cycle, with blood samples taken every 2 to 3 days. The process involves shaving a small patch of fur, inserting a needle to draw blood, and analyzing the sample using an immunoanalyzer. Results can be obtained within 1 to 2 hours. Ovulation test strips are an at-home alternative to monitor ovulation in dogs, detecting estrogen levels in vaginal fluid. While these strips are cheap and easy to use, some users find them to be unreliable. It is important to pay attention to your bitch’s behavior and consult with your vet for accurate testing and monitoring during her heat cycle.
Progesterone levels in dogs double every 2 days once they start to rise, with peak concentrations reached between 20-30 days after oestrus. Progesterone then gradually declines, returning to baseline levels 60-70 days post-ovulation. Regular progesterone testing is crucial to determine the best time to breed your dog in heat. Overall, progesterone testing is the most accurate method to determine if your dog is ovulating.
Progesterone testing is the most accurate method to determine if a dog is ovulating. Progesterone levels double every 2 days once they start rising. Regular testing is important to know when to breed your dog. A rise in progesterone indicates an LH surge and ovulation will occur around two to three days later. The eggs are viable for three to four days after ovulation. Progesterone testing is typically done every 2 days, with re-testing after 4-5 days at basal levels or every 2 days at levels of 2 ng/mL or higher. LH testing is also important for timing dog breedings, starting 3-5 days into the heat cycle with re-tests every 2 days as recommended by the vet. Talk to your vet for more specific information about your dog’s breeding cycle.
Ovulation timing in dogs is crucial for successful breeding, involving the tracking of three key hormones: estrogen, luteinizing hormone (LH), and progesterone. Most bitches are most fertile at nine to eleven days of their estrus cycle, with breeders often mating them five to six days after the LH surge and when progesterone levels rise. Monitoring these hormones helps predict ovulation and determine the best time for breeding. However not all Boerboels or dogs are the same, thus is why you need to test. Estrogen, one of the primary sex hormones in dogs, plays a critical role in regulating the female reproductive system and promoting sexual receptivity. In addition to estrogen, other hormones like FSH and GnRH also contribute to ovulation. Artificial insemination should be timed carefully, especially with chilled or frozen semen that has a shorter lifespan.
Proestrus in dogs is the initial phase of the estrus cycle, marked by external signs of estrogen increase such as vulval swelling and discharge. This phase typically lasts around nine days before a surge of luteinizing hormone (LH) triggers ovulation. During ovulation, a female dog may release multiple eggs, depending on factors like size, age, and breed. LH plays a vital role in supporting estrogen production and signaling ovulation. Testing LH levels alongside progesterone can confirm ovulation timing, as progesterone prepares the reproductive system for pregnancy and rises after ovulation. Monitoring progesterone levels is crucial for timing breedings, with a blood test being the most accurate method. Both LH and progesterone levels are essential for successful breeding outcomes, with LH triggering ovulation about 2 days after a surge and progesterone rising above 5-8ng/mL indicating the optimal time for natural breedings. Vaginoscopy and vaginal cytology are also important tools for assessing fertility, with changes in vaginal mucosa helping determine the reproductive stage of a female dog. Understanding these hormonal and physical changes can assist breeders in determining the best time for breeding their dogs.
Vaginal cytology involves examining cells in a bitch’s vaginal epithelium to monitor estrogen levels. Different stages of the estrous cycle show varying cell types. Progesterone levels are crucial for determining ovulation timing. Testing should start early, with LH surge lasting 12-24 hours and ovulation occurring about 48 hours later. Breeding on days three and five or four and six after the LH surge yields the best conception rate. It’s recommended to breed when progesterone levels rise rapidly after the surge. Pregnancy calculators and calendars can help estimate due dates, as dog pregnancies typically last 63 days. Ovulation in dogs lasts 48 hours after an LH surge, with the egg becoming fertile for four to seven days. Estrogen peaks trigger LH and FSH surges, releasing the egg from the ovary. Consulting a vet for progesterone and LH testing from proestrus day four or five is essential to determine ovulation accurately. Changes in behavior can signal ovulation approaching. Always seek vet advice for successful breeding.
Progesterone levels of 5ng/ml confirm ovulation in dogs, with levels below 1.0ng/ml before. LH surge testing can also predict ovulation. Dopamine and GnRH agonists induce oestrus and shorten anestrus, with cabergoline and bromocriptine as options. Deslorelin implants are effective in over 90% of treated dogs. High pregnancy rates, up to 100%, are possible but vomiting may occur. Implants must be removed in pregnant dogs to prevent luteal insufficiency. Matings should be 24-48 hours apart, with two or three recommended. Artificial insemination with chilled semen follows the same protocol. Peak fertility is around nine to eleven days of estrus, five to six days post-LH surge. Progesterone levels alone do not guarantee pregnancy success. Breeders should communicate mating schedules with stud owners to prevent confusion. Understanding fertility factors can increase the chances of successful conception in dogs.
Understanding the hormonal changes during ovulation timing in dogs is essential for successful breeding outcome.