Ask the Vet: When Do Puppy Balls Drop?
Dr. Ivana Crnec
Help, my puppy's balls haven't dropped, is that normal? This is a common question veterinarians often hear about from concerned puppy owners. Nobody seems to want a puppy with retained testicles, whether it's a show dog or pet puppy. So at what age do puppy balls drop? And most of all, when is it too late? Veterinarian Dr. Ivana provides answers.
A Lesson in Anatomy
Male puppies are typically born with two testicles. However, testicular formation starts much earlier, when the puppy is still in the womb. So let's take a look back into the process.
During fetal development, the testicles form in the abdomen, near the kidneys. After birth, the testicles are slowly being pulled into the scrotum. The pulling is done by a ligamentous cord called the gubernaculum. Simply put, the gubernaculum is what connects the ball to its adjacent scrotal sac.
On its way down into the scrotum, each testicle moves through the abdominal cavity and then through the inguinal canal.
Why is it so important for the balls to descend? The testicles must leave the abdomen so they can produce healthy and motile sperm. This is because the temperature in the abdomen is too hot for normal sperm production. On the other side, the temperature in the scrotum is ideal for sperm production.
An Insight into the "Journey"
At birth, the testicles are therefore still positioned in the pup's abdominal cavity. After birth, the testicles begin to move from the abdominal cavity into their rightful anatomical place – that is, the scrotum.
This journey is called descending. Usually, the testicles descend when the pup is between 2 and 8 weeks old. Nevertheless, it may take up to several months for both testicles to fully descend in some pups. Ultimately, in some dogs, either one or both testicles may never descend.
In normal situations, both testicles are set to descend simultaneously. The exact timing though is different in different dog breeds because of the difference in the puberty-reaching age. However, the two testicles should descend within two months of reaching puberty.
"Dogs are considered to have abnormal testicular descent if both testes are not easily palpable in the scrotum at 6 months of age." ~Margaret V. Root Kustritz, veterinarian specializing in canine reproduction.
Causes of Trouble
At this point, you may be wondering why a puppy's balls fail to descend as expected. A testicle may be retained in the two following situations:
- The gubernaculum is not correctly formed or if it does not function
- The inguinal canal is not correctly formed.
Therefore, the testicle may be displaced in three locations: the abdomen, the inguinal canal or the scrotal subcutaneous tissue.
Certain small and toy dog breeds are more likely to have retained testicles. In larger dog breeds, the condition is more common among brachycephalic individuals. In general, testicle retention is more common among the following dog breeds:
- French Poodle
- German Shepherd
- Miniature Schnauzer
- Old English Sheepdog
- Cairn Terrier
- Yorkshire Terrier
- Shetland Sheepdog
- English Bulldog
- American Staffordshire Terrier
- Siberian Husky.
Did you know? Interestingly, the dog's right testicle is twice as likely to remain in the abdomen. It should also be noted that retained testicles are smaller than their descended pairs and inguinal retained testicles are more prominent than abdominally retained testicles.
The Correct Terminology
It may be helpful differentiating cryptorchidism from monorchidism.
The term cryptorchidism refers to abnormal descending of the testicles. It is a genetic condition passed from father to son. If both testicles are retained, the dog is called bilateral or complete cryptorchid. If only one testicle is retained and the other one is descended, the dog is called unilateral or partial cryptorchid.
Monorchidism is a rare condition in which there is a complete absence of a second testicle. Simply put, a dog with only one developed testicle is called a monorchid. Monorchidism is believed to occur as a consequence of inbreeding and line-breeding.
How to Determine if a Dog Has Two Testicles?
To determine whether a dog has two testicles, you'll have a choice between two different methods. Let's take a look at both of them.
Palpation – to check if both scrotal sacs contain a testicle, gently grasp the scrotum with your thumb and forefinger. This is best performed when the dog is lying on its back or standing. If both testicles are present, they will be easily distinguishable (should be felt as firm and oval-shaped masses). Sometimes it is even possible to palpate a retained testicle. Let your dog lay on his back and press along the abdominal central line. The retained testicle should be felt like a small and soft ball under the skin.
Ultrasound detection – usually, dog owners can determine there is only one testicle, but not which one. In such cases, the vet will perform an ultrasound examination. Once the vet determines which testicle is missing, he/she will evaluate where exactly the retained testicle is positioned. This is important before undergoing surgery so the surgeon would know where to cut.
What Happens if a Puppy's Balls Haven't Dropped?
Retained testicles must be adequately treated, and by treated, we mean removed. This is because, if left in the abdominal cavity, retained testicles are prone to pathological changes such as:
Torsion – a condition that develops when the testicle twists using its spermatic cord as an axis. The torsion will either reduce or completely cut off the blood supply, which leads to death of the testicular tissue. The dead tissue is prone to infection, which may spread and cause a fatal infection of the abdomen. Testicular torsion is a painful condition, and it is classified as a life-threatening emergency.
Cancer – half of the retained testicles will at some point develop neoplastic changes. Compared to a normally descended testicle, a retained testicle has a ten times higher risk of developing testicular cancer. Testicular cancer is the second most commonly reported cancer in male dogs. In 20 percent of the cases, the tumor has already spread by the time a diagnosis is made.
Can a dog's retained testicle be artificially descended? A retained testicle can be artificially descended through a combination of surgery and hormones. The surgery includes suturing the retained testicle to the scrotum. The heavy suture plays the role of the gubernaculum (pulls and holds the testicle down). Over time, scar tissue will form where the suture is and hopefully permanently bind the testicle to the scrotum. Meanwhile, the patient is put on hormonal therapy. The hormones' goal is to enlarge the testicle, thus preventing its return into the abdomen or inguinal canal.
This approach has a limited success rate because the sutures can break, and the hormones may trigger side-effects that will prevent them from further use. Generally speaking, the success rate is classified as moderate in patients with inguinal retained testicles and low in abdominal cryptorchids.
A Genetic Fault
Cryptorchidism is considered a severe fault, and artificial descending does not prevent the defect from being passed on to the offspring. Therefore, most vets disapprove of this alternative and recommend neutering cryptorchid dogs.
Being a genetic fault, dogs with one retained testicle must not be bred. Additionally, cryptorchid dogs are more likely to have additional, hidden congenital issues such as hip dysplasia, patellar luxation, penile defects, prepuce defects, inguinal hernia, and umbilical hernia.
All in all, a cryptorchid dog should have both its retained and descended testicle removed, preferably at the same time.
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia.