Castration involves the removal of the gonads—the testicles in men—or the ovaries (often along with the uterus) in women. Sterilization involves cutting or ligating the spermatic cord or fallopian tubes without removing these organs. After castration, the gonads stop producing sex hormones, whereas after sterilization, the hormones continue to function. Both procedures can be performed on both men and women, although colloquially, the procedure is called "sterilization" for women and "castration" for men.
To sum it up
- Castration = removal of the gonads (testicles or ovaries); sterilization = cutting of the spermatic cord or fallopian tubes, the organs remain in the body.
- After castration, estrus and sex hormone-dependent behavior disappear; after sterilization, the animal will not have offspring, but the hormonal cycle and libido will remain.
- The procedure that dog and cat owners call "spaying a female dog or cat" is, in practice, usually castration (removal of the ovaries or ovaries along with the uterus).
- It is always worth agreeing on the date and type of procedure with your veterinarian.
What is castration?
Sterilization — is the surgical removal of the gonads, the organs that produce reproductive cells and sex hormones. In male cats, both testicles are removed. In female cats, the ovaries are removed—this procedure is called oophorectomy - or they remove both the ovaries and the uterus, as they say ovariohysterectomy . The choice of method depends on the doctor and the animal's health condition.
Since the gonads are the primary source of testosterone (in males) and estrogen and progesterone (in females), their levels drop significantly after castration. Females cease to go into heat, and testosterone-dependent behaviors such as urine marking or chasing females in heat typically diminish. The extent of these changes varies depending on individual characteristics and the age at which the procedure was performed.
What is sterilization?
Sterilization, Strictly speaking, it's a procedure that prevents reproduction but does not remove the gonads. In men, the spermatic cord is cut or tied (similar to a vasectomy in humans), and in women, the fallopian tubes are severed. The testicles and ovaries remain in place and continue to produce hormones.
As a result, the animal does not reproduce, but maintains its natural hormonal cycle . A spayed female or female cat continues to experience heat, while the male retains his libido and typical behavior. For this reason, spaying in the strict sense is rarely performed on domestic dogs and cats—most procedures involve neutering.
Castration and sterilization – why is there such confusion in the names?
In everyday speech, it's common to think of castration as applied to males and spaying as applied to females. We often refer to "female neutering" or "male cat spaying," although both terms typically imply the removal of the gonads. Technically, most veterinarians perform castration on both males and females, and "spaying" has become the common term for this procedure in females.
In practice, when you schedule a spay or neuter appointment with your veterinarian, you're most likely referring to an ovariectomy or ovariohysterectomy. If you're interested in a specific procedure, ask your veterinarian which organs will be removed.
Comparison Chart: Neutering vs. Spaying
| Characteristic | Castration | Sterilization (in the strict sense of the word) |
|---|---|---|
| What is done for a man? | Removal of testicles | Cutting/ligation of the vas deferens |
| What do they do with a woman? | Removal of the ovaries (or ovaries and uterus) | Tubal ligation/cutting |
| Sex hormones from the gonads | Their production is disappearing. | Production continues. |
| Heat / heat period | It gives way | It's still happening. |
| Sexual attraction and behavior | Usually they weaken | They remain |
| Diseases of the reproductive organs | Eliminates diseases of remote organs (for example, pyometra after hysterectomy). | It does not protect against diseases of the ovaries, uterus, or testicles. |
| Popular among dogs and cats. | The most commonly performed procedure | Rarely performed |
Benefits and possible side effects
Both procedures prevent the birth of unwanted offspring. However, spaying has other health consequences as well. In females, spaying reduces the risk of developing mammary tumors—according to veterinarians, this is especially noticeable if the procedure is performed early, before the onset of subsequent menstruation—and hysterectomy eliminates pyometra , a life-threatening disease. In males, castration eliminates testicular disease.
After castration, energy requirements decrease, and appetite often increases. Without changes to diet and portion sizes, an animal can easily gain weight, so veterinarians recommend monitoring weight and adjusting diet after the procedure. Like any surgery performed under general anesthesia, castration and sterilization also carry a risk of perioperative complications, which the veterinarian will discuss with the animal prior to the procedure.
Sterilization in the strict sense of the word does not alter the hormonal balance, therefore it does not affect hormone-dependent behavioral reactions and does not protect against diseases of the reproductive organs.
Neutering or spaying – which one to choose for your dog or cat?
- If you want to avoid heat, marking territory, running away and reproductive system diseases , castration is usually recommended.
- You are only concerned about the lack of offspring and you want to maintain your hormonal balance - You can ask about sterilization, but not every clinic offers this service, and you need to consider the possibility of her coming into heat again.
- Time of the procedure It depends on the animal's species, gender, breed, size, and health. For large breeds, veterinarians sometimes recommend waiting until the dog is fully grown—this is an individual decision.
- After the procedure It is necessary to take care of the wound (use a collar or postoperative underwear), limit movements in accordance with recommendations and adjust the diet.
The final decision on the type of procedure and timing should be made in consultation with a veterinarian who is familiar with your pet's medical history.
Frequently Asked Questions (FAQ)
What is the difference between castration and sterilization?
Castration is the removal of the gonads (testicles or ovaries), which stops the production of sex hormones. Sterilization involves cutting or ligating the spermatic cord or fallopian tubes—the animal cannot reproduce, but the hormones continue to function.
Does sterilization only apply to women and castration only apply to men?
No. Both procedures can be performed on both men and women. This is simply a common usage of the term—"sterilization" typically refers to the procedure performed on women, although in practice, the term "castration" is more commonly used.
Does a cat go into heat after sterilization?
After spaying (strictly speaking, tubal ligation) – yes, because the ovaries continue to function. After castration, or removal of the ovaries, heat ceases. If your cat continues to show signs of heat after the procedure, consult a veterinarian.
Does a dog change after castration?
Testosterone-dependent behaviors, such as territorial marking or chasing, typically decrease. The dog's personality remains largely unchanged. Appetite often increases, so it's important to monitor weight.
What is better for a cat: castration or sterilization?
Spaying is most often performed on indoor cats because, in addition to preventing litters, it also reduces heat and territorial markings, and protects against diseases affecting distant organs. It's always worth discussing this option with your veterinarian.
See also
- What is the difference between hysteroscopy and curettage?
- What is the difference between white and red surgery?
- What is the difference between a procedure and an operation?
- How are pregnancy symptoms different from menstruation symptoms?