Spaying and neutering your golden retrievers is an important responsibility that can not be overlooked. As a pet owner, you must ensure the health and well-being of your beloved furry friend.
And although spaying and neutering help to control the issue of overpopulation, which is a significant problem in the animal community, especially in South Florida, for goldens retrievers and other medium to big breeds, could lead to serious health issues if it is performed in the wrong age.
In this post, we will be discussing why sexual hormones are important for dogs. What function do they have for the good development of our goldens. The consequences of early removal of the sexual gonads on big breeds. And also will be discussing alternative surgeries for our goldens aside from the traditional spay and neuter.
List of Content
- A quick review of a dog’s reproductive system
- Male reproductive system
- Female reproductive system
- The function of the sexual hormones
- Different types of canine sterilization
- Comparison of Traditional and alternative surgeries. Risk and Benefits
- Exploring How Spay/Neuter Impacts Long-Term Health in Dogs
- The decision on the timing of sterilization
A quick review of a dog’s reproductive system
Reproduction is how a species can perpetuate itself. All species of mammal have evolved separate sexes and they reproduce sexually. Sexual reproduction involves the transfer of genetic material. After mating specialized germ cells – spermatozoa from the male and ova from the female – fuse to form a single-celled zygote. The zygote undergoes cell division to form the embryo. The offspring resulting from sexual reproduction are genetically different from each other and their parents.
The reproductive system of the dogs shares part of its structure with the urinary system and the combined systems may be referred to as the urogenital system.
Male reproductive system
- Testis is the male gonad, with functions as follows:
- To produce spermatozoa (sperm) by the process of spermatogenesis; these fertilize the ova produced by the female
- To produce a little fluid to transport the sperm from the testes into the female tract and to aid their survival
- To secrete the hormone testosterone which influences spermatogenesis, the development of male secondary sexual characteristics and male behavior patterns
- The deferent duct also called the vas deferens. The function of the vas deferens also referred to as the ductus deferens, is to transport sperm from where it is stored into the urethra when the sperm is readily mature and ripe for semination.
- Urethra. Is a tube directly located inside the penis for easy passage of fluids. The fluids in a male’s anatomy need somewhere to easily pass through to be expelled, however, there needs to be an accommodating source that controls the flow of conflicting fluids, such as urine and semen. When the penis is erect, the urethra blocks the flow of urine to allow the easy passage of semen until ejaculation is complete. When the male is not aroused, urine is passed through.
- Penis The penis is the physical organ used in coitus and is the organ responsible for achieving the copulatory tie with the female. This organ is comprised of: the root, the base (shaft), and the cone-shaped end of the penis called the glans.
- Prostate gland – an accessory gland that functions mainly as a passageway for prostate fluid to flow. The fluid that flows via the prostate is for the nourishment and sheer protection of the semen.
- Bulbus Glandiscommonly referred to as the bulbourethral glands or the Cowper’s Glands are located on the sides of the urethra. The shape of these two structures are small, similar to the shape of a pea, and are found just below the male prostate gland. The primary function of the bulbus glandis is to produce the fluids in the urethra that serve to neutralize the acidity of the environment that may develop from the residual fluids of urine inside the urethra. This gland also works to lubricate the urethra.
- Semen & Sperm. viable liquid that is expelled from the urethra and penis during ejaculation. The semen is a protective fluid and is what carries the sperm, the reproductive cells. The semen fluid contains spermatozoa, fructose, enzymes, and proteolytic and functions mainly as the carrying vehicle for the sperm cells.
The male reproductive system is comprised of hormones that act as the catalysts for cell activity. Reproductive cells and organs within the dog’s body are regulated by hormonal chemicals. Three primary hormones are involved in the male reproductive system: testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH). Both LH and FSH are produced by the pituitary glands in the brain. The LH hormone stimulates testosterone production while the FSH hormone stimulates sperm production. Testosterone is responsible for producing the masculine qualities in the male including sexual drive, muscle and bone mass, and fat distribution.
Female Reproductive System
- Ovaries are the female gonad. The functions of the ovaries are:
- To produce ova or eggs ready for fertilization by the sperm of the male
- It acts as an endocrine gland, secreting the hormones estrogen and progesterone.
- Uterine tube, oviduct, or Fallopian tube. The functions of the uterine tubes are
- To collect ova as they are released from the Graafian follicles
- To convey the ova from the ovaries to the uterine horns
- To provide the correct environment for the survival of both the ova and sperm.
- Uterus – uterine horns and body is a Y-shaped structure lying in the midline of the dorsal abdomen. Function:
- To provide a receptacle in which the embryos can develop into full-term fetuses
- To provide the correct environment for the survival of the embryos
- To provide the means whereby the developing embryos can receive nutrients from the dam – this is made possible by the placenta.
- Cervix The cervix is a short, thick-walled muscular sphincter that connects the uterine body with the vagina. Running through the center is a narrow cervical canal, which is normally tightly closed and relaxes only to allow the passage of sperm or fetuses.
- Vagina and Vestibule. Both form a channel leading to the external opening of the reproductive tract – the vulva. The vagina leads from the cervix to the external urethral orifice – the point at which the urethra joins the reproductive tract. The vestibule leads from the external urethral orifice to the vulva and is shared by both the urinary and reproductive tracts.
- Vulva. The vulva marks the external opening of the urogenital tract. It consists of two parts:
- The labia – two vertical lips joined dorsally and ventrally; the vertical slit between them is known as the vulval cleft. They are typically held closed to prevent the entry of infection. During pro-estrus and estrus in the bitch, the labia enlarge.
- The clitoris – a knob-like structure of cavernous erectile tissue lying in the clitoral fossa just inside the ventral angle of the vulval cleft. It is the equivalent of the male penis.
- The mammary glands. Although these are not strictly part of the reproductive tract, they are essential to reproduction in the mammal. The presence of mammary glands is the defining characteristic of the class Mammalia. All mammals feed their young on milk produced by the glands during a process known as lactation.
The female dog reproductive cycle is governed and constantly regulated by hormones in the body located both in the brain and the ovaries. The hormones influence the fertility of the dog as well as regulate how the reproductive organs operate and function as well as their changes. In the female dog, the follicle-stimulating hormone (FSH) is located at the base of her brain in the pituitary gland and sends the signal for the development of the eggs in their follicles. Eggs, once fully formed, will be able to form their hormones. Estradiol 17B hormones are made by the follicles to dominate the follicular phase. Once matured, the luteinizing hormone (LH) is produced for the stimulation of the ovulation phase. Progesterone and estrogen are the two main sexual hormones in a female dog and can be produced from the ovaries or the adrenal glands. Estrogen prepares the reproductive tract for breeding, assists in the motility of the female and male gametes, and affects her behavior to make her more attractive to males. Progesterone, also like other steroids, can reduce the body’s sensitivity to hormones like insulin that are helpful to glucose control- this is helpful to a pregnant mother with young, growing babies that require large amounts of energy as they develop into late pregnancy, but can lead to poor glucose control (gestational diabetes) in some bitches.
The function of the sexual hormones in a dog system
Recent research demonstrates an association between the reproductive status of dogs and numerous long-term health effects. Gonads are not merely gamete-producing or ancillary sex/reproductive organs but rather they are necessary endocrine glands for normal metabolic, behavioral, musculoskeletal, and anti-neoplastic health.
Some of Gonad’s functions are:
- Development of secondary sex characteristics
- Estrogen production and its role in bone and cartilage homeostasis for normal joint development and maintenance of bone and cartilage strength
- Gonadal androgen production and its role in the maintenance of muscle mass and strength as well as regulation of fat deposition
- Neuroprotective function of testosterone and estrogen
- Sex steroid modulation of immune function by enhancing tissue self-recognition.
Different types of canine sterilization
- Ovariohysterectomy (spay; which removes both the ovaries and the uterus)
- Orchiectomy (neutering; which involves removing the testicles)
- Ovariectomy: Remove only the ovaries, leaving the uterus. The impact is similar to ovariohysterectomy.
- Hysterectomy or Ovary Sparing Spay (Removes the uterus and cervix, while leaving one or both of the ovaries intact for physiologic, health, and/or behavioral reasons)
- Vasectomy (Removing a piece of the spermatic cord (vas deferens) to prevent transport of sperm from testicles during ejaculation)
Comparison of Traditional and alternative surgeries. Risk and Benefits
Exploring How Spay/Neuter Impacts Long-Term Health in Dogs
Evidence has been accumulating since the late 1980s that gonadectomized dogs have significant health implications. Literature reviews have compiled evidence across breed lines showing definite effects caused by removing the gonads, aside from population control.
Some of these impacts are:
- Obesity occurs in about 3% of the total canine population; however, up to 50% of gonadectomized dogs are obese.
- Hip dysplasia, anterior cruciate ligament rupture, and intervertebral disc disease increased in gonadectomized dogs of susceptible breeds. These issues are worse in gonadectomized dogs before puberty, as the growth plates close later, and abnormal joint angles are subjected to more stress.
- Urinary incontinence has an increased incidence in neutered female dogs. The collagen-to-muscle ratio changes after neutering, which negatively affects urethral function.
- Hypothyroidism increased after gonadectomy
- Immune-mediated disease (atopic dermatitis, autoimmune hemolytic anemia, hypoadrenocorticism, hypothyroidism, and immune-mediated thrombocytopenia) increased in incidence in all gonadectomized animals, and lupus increased in neutered bitches.
- Behavior: Although castration decreased roaming behavior some studies show that gonadectomized dogs were more fearful, anxious, excitable, and less trainable. Is well known now that castration does not remove behavioral problems.
- Neoplasia: Mammary tumors (malignant in half of cases) had a decreased incidence in spayed bitches in some studies. Prostatic tumors (almost always malignant) had an increased incidence in neutered dogs. Bladder cancer (often malignant) was more prevalent in gonadectomized dogs. Testicular cancer (rarely metastasizes) occurs in aged male intact dogs; castration is curative. Hemangiosarcoma (variably malignant), osteosarcoma (often malignant), lymphosarcoma, and mast cell tumors had an increased incidence in gonadectomized dogs.
The decision on the timing of sterilization
Definitely is not a simple choice, especially with the overpopulation problem and nonethical breeders making decisions based only on profit. But also we need to consider the health of our pps, especially Golden Retrievers that are at higher risk of musculoskeletal problems and developing cancer.
One recommendation that we discuss, especially in goldens, is waiting until sexual maturity which is 2 years or 24 months of age. By that time goldens already have their hips totally developed and are completely mature.
Remember to always discuss with your vet about the matter, every dog is a case-to-case basis.
Also, you can discuss alternative surgeries like vasectomy or ovary-sparing spay as a way to maintain hormonal levels in your pups
Sources:
- Davis Veterinary Medical Teaching Hospital.
- AKC Canine Health Foundation
- AVMA Journals (American Veterinarian Medical Association)
- Morris Animal Foundation: Golden retriever Lifetime study
