Recently, I delved into a fascinating study… on the microbiome of dog semen. This topic obviously piqued my interest as a reproduction specialist! Indeed, my recent blogs have explored the gut microbiome —a hot trend in both human and veterinary medicine— in puppies and kittens, but it’s clear that bacteria’s role extends far beyond. This revelation about semen’s microbiome intrigued me: What secrets could it unveil about male dog fertility, and how might this knowledge revolutionize breeding practices? As someone deeply entrenched in reproductive health, I was eager to uncover how these insights could aid dog breeders. This compelling research inspired me to share my thoughts on the current landscape of male dog fertility tests and the exciting directions we’re headed.
- At What Age Can Male Dogs Start Breeding?
- How Can You Ensure Your Male Dog Is Fertile?
- Common Fertility Issues and Solutions
At What Age Can Male Dogs Start Breeding?
Understanding Male Dog Sexual Maturity
When it comes to male dog breeding, one pivotal question should always takes center stage: At what age can a male dog begin breeding successfully?
Understanding the intricacies of male dog fertility age is crucial for any responsible breeder or dog owner. After all, timing is everything in the delicate dance of dog breeding.
In my experience, there are three common pitfalls that many fall into due to a lack of understanding about male dog fertility.
First, there’s the issue of premature fertility.
Many are taken by surprise when their apparently young male dog unexpectedly sires a litter…
Then, there’s the eagerness to breed too soon.
It’s a common misconception that a male dog is ready to sire strong, healthy litters the moment it shows the first signs of sexual interest. This rush can lead to infertility or disappointingly small litters.
This is particularly problematic in large breeds where “single puppy syndrome” can pose significant birthing challenges.
Conversely, waiting too long can be equally detrimental.
As male dogs age, the quality of their semen can decline, reducing their chances of successful fertilization.
Yes, it is indeed a delicate balance, navigating the prime breeding age to ensure the vitality of the offspring and the health of the breeding dogs involved.
So, when is the right time?
Biology, as always, offers a variety of answers, each tailored to the individual dog.
However, some general guidelines can steer us in the right direction.
The onset of puberty in male dogs is closely tied to their adult size, which means:
| Size of the dog | Age when they reach puberty |
| Small dogs (under 10kg or 22 pounds) | 4-6 months |
| Medium dogs (10-25kg or 22-55 pounds) | 6-8 months |
| Large dogs (25-45kg or 55-99 pounds) | 10-12 months |
| Giant dogs (over 45kg or 99 pounds) | 12-24 months |
This is important information to keep in mind!
There is this story I like to tell during my presentations, of two Dachshund littermates left together because “they were young puppies”.
At just 4 months old, the male managed to impregnate the female… leading to an entirely unexpected litter.
This story happened a long time ago, but it is still a stark reminder that nature has its own timetable, often irrespective of our human schedules and expectations.
It’s important to distinguish between puberty and sexual maturity.
While puberty signifies the beginning of sperm production, these early ejaculates often lack the potency for successful fertilization. True sexual maturity, marked by the production of fertile sperm, typically aligns with the dog reaching its adult size, which varies significantly across breeds.
| Size of the dog | Age when they reach their adult size |
| Small dogs (under 10kg or 22 pounds) | 10 months |
| Medium dogs (10-25kg or 22-55 pounds) | 12 months |
| Large dogs (25-45kg or 55-99 pounds) | 15 months |
| Giant dogs (over 45kg or 99 pounds) | 18-24 months |
Given these complexities, the prudent path is to wait until a male dog has not only reached sexual maturity but has also achieved full physical development.
This approach not only increases the chances of successful breeding but also supports the health and well-being of both the male dog and his potential offspring.
Signs of Fertility in Male Dogs
When considering a male dog for breeding, one of the first signs breeders tend to look for is interest in females, especially those in heat.
This behavioural trait is often perceived as a green light, signalling that the male is ready to contribute to the next generation.
However, it’s essential to understand that this is merely an external indicator and doesn’t necessarily equate to actual fertility.
Behavioural readiness, such as showing keen interest in females or displaying mating behaviours, indeed suggests that a male dog is reaching a reproductive phase. Yet, this alone cannot guarantee fertility.
The true measure of a male dog’s ability to sire lies not just in his eagerness but in the viability and quality of his sperm.
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It’s a distinction worth noting: while a behaviour might hint at readiness, fertility potential is an entirely different matter, one that requires more in-depth analysis.
In my professional journey, I’ve encountered numerous cases that defy conventional expectations.
There have been instances where dogs showed little to no interest in females, regardless of their reproductive status, yet their sperm analysis revealed excellent fertility potential.
Conversely, and perhaps more commonly, dogs with high libido and apparent readiness to mate have been found to produce no sperm at all.
These examples highlight the complexity of canine fertility and the pitfalls of relying solely on observable behaviours.
At the heart of assessing male dog fertility is the critical examination known as the spermogram.
This detailed analysis of a dog’s semen is the cornerstone of understanding his fertility potential.
A spermogram goes beyond mere observation, providing a comprehensive look at sperm count, motility, morphology, and other vital parameters that influence a dog’s ability to sire puppies.
It’s a crucial tool for breeders and veterinarians alike, offering the clearest picture of a stud dog’s breeding capabilities.
Health Checks Before Breeding
Before considering a male dog for breeding, conducting a Breeding Soundness Examination is imperative in my opinion.
This comprehensive veterinary assessment ensures the dog is physically and genetically fit for breeding, an aspect often overlooked but crucial in the realm of responsible dog breeding.
A key component of this exam is evaluating the dog’s Body Condition Score.
These days this is ALWAYS where I’d start!
It’s alarming to note that studies reveal up to 20% of show dogs are either overweight or obese.
While many are aware of the common health issues linked to obesity in dogs, such as joint stress, diabetes, and cardiovascular problems, its impact on fertility is less known but equally significant.
Excess fat, particularly around the scrotal area, can lead to an increase in testicular temperature. Given that the testes reside outside the abdomen in the scrotum to maintain a lower temperature essential for sperm production, any temperature rise can halt sperm cell development.
Moreover, adipose tissue is hormonally active, producing sex hormones in small quantities.
Though these amounts are minimal, the reproductive system’s sensitivity to hormonal fluctuations means even slight changes can disrupt its finely tuned balance.
This is true not only in dogs but in humans as well, underscoring the universal importance of maintaining a healthy weight for reproductive health.
The Breeding Soundness Evaluation also provides an opportunity to inspect the male dog’s genital tract.
This includes ensuring the normal conformation of the penis and testes, which should both be present in the scrotum.
The presence of an ectopic testis, where one testis fails to descend, indicates a genetic disorder, rendering the male unsuitable for breeding.
More about ectopic testes in those two blogs I wrote on the topic:
Doc, there one “ball” missing: is it going to be a problem?
Ectopic testis in puppies: what’s the prognosis?
Another vital aspect of this exam is the canine brucellosis test, particularly recommended in North America.
The Society for Theriogenology advises, “All dogs intended for breeding should be appropriately tested for canine brucellosis to prevent the spread of this disease. At a minimum, both members of a breeding pair should be tested before each breeding. All dogs intended for breeding should be regularly tested for canine brucellosis, either at the time of breeding or every six months.”
This recommendation is especially pertinent given the recent resurgence of canine brucellosis in North America and Western Europe, dispelling the myth that it’s a relic of the past.
How Can You Ensure Your Male Dog Is Fertile?
The Importance of Regular Veterinary Visits
During my tenure at the veterinary school in Paris, it was rare to encounter consultations specifically focused on fertility control in male dogs.
Reflecting on this, I firmly believe the narrative needs to shift towards a more proactive approach in managing male canine fertility.
There’s timeless wisdom in the adage, “An ounce of prevention is worth a pound of cure,” and the more I think about it, the more I realize this holds particularly true in the realm of canine reproduction.
Regular fertility assessments serve a critical function, allowing us to monitor the semen quality of male dogs continually.
This ongoing evaluation provides a baseline, facilitating the early detection of any emerging fertility issues.
Unfortunately, the current trend leans towards reactive measures rather than preventive ones.
For instance, semen analysis is often conducted with the intent to freeze semen, usually when the dog has achieved certain milestones or titles.
However, this delay can be detrimental; by the time these achievements are attained and arrangements for semen freezing are made, the semen quality may no longer be optimal for the freezing process.
It’s a common oversight, with many failing to realize that semen quality, much like many biological attributes, is at its peak during the younger years of a dog’s life.
Furthermore, veterinary intervention is frequently sought only after a male dog has unsuccessfully bred multiple females, none of which resulted in pregnancy.
This reactive stance not only complicates the fertility issue but also limits the options for effective intervention.
In contrast, adopting a proactive approach to fertility management could significantly enhance the outcomes of breeding programs.
The Society for Theriogenology underscores the importance of routine veterinary evaluations for stud dogs, particularly for the early detection and management of prostate and testicular diseases.
On my end, I think it would be ideal if this kind of assessment could be performed on stud dogs at least on an annual basis, to ensure ongoing health and fertility.
The role of the Spermogram
To truly understand a male dog’s fertility potential, a spermogram stands as the gold standard among tests.
This procedure involves collecting semen, typically through masturbation, with the presence of a teaser female sometimes facilitating the process. However, keep in mind that seasoned dogs accustomed to semen collection might not always require this.
The collected semen is divided into three distinct phases:
| Fraction of the ejaculate | Description |
| Pre-sperm fraction (or 1st fraction) | Mainly prostatic fluid, translucid and can sometimes be contaminated with urine. Its main role is to lubricate the female genital tract before mating. |
| Sperm-rich fraction (or 2nd fraction or Spermatic Phase) | Contains the spermatozoa. Its color is NOT an indicator of quality, but just a reflection of the concentration of the sperm. The whiter, the more concentrated. |
| Post-sperm fraction (or 3rd fraction or Prostatic Phase) | Again mainly prostatic fluid. Large volume compared to the other fractions. Typically translucid. Also serves to flush out the remaining sperm from the urethra. |
The spermogram focuses on analyzing the sperm-rich fraction to assess critical parameters that define the semen’s quality.
Three main aspects are meticulously examined during a spermogram: motility, numeration, and morphology.
Motility refers to the movement and agility of sperm cells, a vital attribute for successful fertilization.
Numeration is the sperm count in the ejaculate, indicating the volume of potential fertilizers.
Morphology studies the shape and structure of sperm cells, identifying any abnormalities that could hinder their fertilizing capability.
Based on these observations, veterinarians can determine the semen’s quality and, by extension, the male dog’s breeding viability.
| Parameter | How it is assessed in veterinary clinics | Interpretation |
| Motility | Examination under the microscope CASA (Computer Assisted Semen Analysis) | >80%: good >50-80%: average <50%: poor |
| Numeration | Thomas Cell Counting Chamber Spectrophotometer | Depends on the size of the dog, this is what is considered normal: Small Dogs: 400-600 Million Sperm Cells/Ejaculate Medium Dogs: 600-800 Million Sperm Cells/Ejaculate Large Dogs: 800-1,000 Million Sperm Cells/Ejaculate Giant Dogs: >1 Billion Sperm Cells/Ejaculate |
| Morphology | Examination under the microscope (Spermac, eosin-nigrosin staining) | <30% abnormal forms: Good 30-50% abnormal forms: Average >50% abnormal forms: Poor |
However, it’s crucial to remember two factors that underscore the complexity of canine fertility.
Firstly, sperm production in dogs typically spans approximately 63 days.
This duration implies that any adverse event, such as illness, injury, or treatment within this period, could detrimentally affect semen quality.
It is, therefore, standard practice to wait at least two months post-recovery before reassessing a stud dog’s semen quality to allow for the regeneration of a healthy sperm population.
Moreover, various external factors can influence sperm quality.
For example, during an exceptionally hot summer in Paris, I observed a significant decline in semen quality among Leonbergers, a breed known for its robustness.
The elevated temperatures had probably impacted spermatogenesis, the process of sperm production. And with the arrival of cooler autumn temperatures, a subsequent evaluation revealed a remarkable improvement in their semen quality, highlighting the transient nature of some fertility issues.
Stress, too, plays a pivotal role in semen production.
The stress-induced hormone cortisol can adversely affect the quality of sperm, reinforcing the need for a calm and stable environment for breeding dogs.
Given these variables, a single spermogram might not paint the full picture of a dog’s fertility. It is advisable to conduct two to three spermograms, spaced at least two months apart, to gain a comprehensive understanding of the dog’s true fertility potential.
Ultrasound Examination of the Male’s Reproductive System
Another pivotal diagnostic tool comes to the forefront: the ultrasound examination of the genital tract, focusing particularly on the testes and the prostate.
This non-invasive imaging technique provides a window into the internal workings of a stud dog’s reproductive system, offering invaluable insights that go beyond the surface.
The prostate, being the only gland in the male dog’s genital tract, plays a critical role in fertility.
Astonishingly, its secretions constitute over 90% of the ejaculate volume.
This highlights a straightforward fact: any condition adversely affecting the prostate has the potential to significantly impact fertility.
Prostatic disorders, unfortunately, are not uncommon in stud dogs.
As dogs age, the prostate tends to enlarge, a condition known as benign prostatic hyperplasia (BPH). While many dogs with BPH may not show outward symptoms, the condition can stealthily undermine fertility.
Hormonal Insights: The Role of Estrogen Levels in Assessing Canine Fertility
Hormonal blood tests also emerge as a critical tool in our diagnostic arsenal.
While the measurement of testosterone might be the more obvious choice, its relevance fades in cases where the male dog exhibits normal libido.
Instead, my attention turns to a less expected hormone in male dogs: estrogen.
Estrogens, typically associated with female reproductive health, can reveal significant insights when present in elevated levels in intact male dogs.
High estrogen levels in these dogs can signal an underlying condition known as testicular degeneration.
To put it simply, testicular degeneration refers to the gradual deterioration of the testes, which can lead to a decrease in sperm production and overall compromised fertility.
This condition can stem from various causes, including age, infections, or even genetic factors, leading to the progressive loss of testicular function.
When faced with a male dog struggling with infertility, detecting elevated estrogen levels can be a red flag. It suggests that not only is the dog’s fertility at risk, but there might also be irreversible damage to the testicular tissue.
In such cases, the prognosis for natural fertility restoration is grim.
The presence of high estrogen levels in a male dog not only points towards current reproductive issues but also indicates a potentially irreversible decline in the dog’s ability to sire offspring.
Semen Cultures in Canine Fertility?
The realm of canine fertility testing often brings us to the crossroads of tradition and innovation.
One traditional approach that frequently arises is the culture of ejaculate to identify any abnormal bacterial infections. This is something I hear about on a very regular basis…
Initially, I harboured skepticism towards this method, primarily because semen is inherently not sterile.
We almost always encounter some level of bacterial presence, rendering the interpretation of these results a nuanced challenge.
This skepticism was why this recent study I mentioned earlier caught my eye, shedding light on the relationship between semen quality and bacterial communities within the male dog’s ejaculate.
The study unveiled several compelling insights that merit attention.
Firstly, it debunked the necessity of distinguishing between culturing the second (spermatic) and third (prostatic) fractions of the ejaculate.
Discovering that both fractions yield comparable results simplifies the collection process significantly, especially considering the larger volume of the prostatic phase.
This simplification could streamline the analysis, making it more accessible and less cumbersome.
Secondly, the revelation that semen bacterial communities remain consistent across normospermic (normal sperm) and teratozoospermic (lots of abnormal sperm in the ejaculate) dogs was particularly striking.
While this is an initial study and the customary caveat of “further research is required” applies, it suggests a pause before rushing into bacterial analyses of male dog ejaculate.
The current body of knowledge doesn’t yet justify a widespread adoption of this practice without a clearer understanding of its implications in my opinion.
The discussion surrounding Mycoplasma in semen was another highlight of the study.
Mycoplasma, a common bacteria found in the genital tract of many organisms, including dogs, often leads to debates about its significance.
The study pointed out that an overwhelming majority of male dogs (89%!!!!) naturally harbour Mycoplasma in their reproductive system.
This raises critical questions about the interpretation of qualitative PCR results that detect the presence of Mycoplasma.
Without a quantitative threshold to distinguish normal from excessive levels in canines, the pathogenic role of Mycoplasma in male infertility remains ambiguous to say the least.
Often, Mycoplasma is considered a secondary pathogen, flourishing under conditions set by a primary issue.
This insight urges a cautious approach before embarking on extensive antibiotherapy, which could potentially lead to antibiotic resistance and disrupt various microbiomes – and today we know that those are SUPER important for the health of our animals!
Common Fertility Issues and Solutions
Read some of my previous blogs on this topic to find out more:
Dog Breeding Insights: Beyond the Ruler!
Bad semen quality? This is what you need to check.
Diving into this paper was a delightful journey back to the fundamentals I cherished during my veterinary school days, where we tackled male infertility cases with earnest dedication. While the cutting-edge techniques outlined in the study were beyond our reach back then, our approach, though less technologically advanced, effectively served our dog breeder clients. Reflecting on the progress, it’s exhilarating to envision a future enriched with innovative tests like semen microbiome analysis, promising deeper insights and breakthroughs in canine fertility. Yep, we stand on the brink of these advancements, and there’s an undeniable breeze of change in the air, heralding a new era in reproductive veterinary medicine. No doubt that on my end, I look forward to the enhanced understanding and solutions!
One of the most common challenge we encounter in breeding kennels is NEONATAL MORTALITY.
It can be very frustrating… even heart-breaking.
Good news though : you can do something about it !
We now have more knowledge than ever in this discipline.
In recent years, new research brought us a much better understanding of what can be done to optimize the health of newborn puppies.
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DR. EMMANUEL FONTAINE 