Estrus (Heat) in Dogs

The fertile period of a female animal's reproductive cycle (the mating period) is called estrus, commonly referred to as "heat" or being "in season". The female will not mate with a male except during this period. The average female cat (queen) or dog (bitch) reaches sexual maturity at about 6 months of age. Some female cats and small-breed dogs begin to cycle sooner.

Mating Behavior in Bitches
Bitches (female dogs) normally go into "heat" every 6 months. Each cycle normally lasts 1-2 weeks. A bitch in heat may show little change in temperament or activity as compared with the exaggerated displays of many female cats. Some dogs become somewhat lethargic, while others become anxious and possibly aggressive. The bitch may become restless, making frequent escape attempts.

At no time should a bitch in heat be left unsupervised in the backyard or off a leash during walks. Close supervision prevents undesired mating or injury.

During walks, the estrual female urinates more frequently than usual, leaving a trail of scent to your home.

Male dogs can detect powerful chemical signals in vaginal secretions and urine from a distance of several miles. The estrual bitch may also attract neutered dogs that are aroused by the changes they sense.

If your dog has been undesirably bred, contact your veterinarian within the first few days after mating to discuss your options.

Physical changes associated with estrus tend to be more obvious in bitches than in queens. The nipples may become slightly enlarged in anticipation of milk production associated with pregnancy. The vulva may appear inflamed and swollen, with a normal bloody discharge. These physical changes normally regress if the bitch does not become pregnant.

During intercourse, the male dog's penis becomes engorged with blood, and the male may be unable to detach himself from the female for as long as a half hour. During this period, it is normal for the male to dismount and stand tail to tail with the female, joined by his penis. Do not be alarmed by this sight, and do not try to separate them. When the male dog's erection subsides, the dogs become separated.

Spaying Prevents Estrus
Spaying your female cat or dog is a surgical procedure usually performed at 6 to 8 months of age. There are many more reasons to have your pet spayed than not to have it spayed.

• An animal does not have to experience "heat" or have a litter to lead a healthy and happy life. In fact, their lives may be healthier and happier because neutering may prevent many physical problems and emotional stress.
• Spaying female animals prevents unwanted pregnancies and keeps your pet from contributing to overpopulation of pets. Millions of dogs and cats are needlessly destroyed every year.
• Spaying your pet also avoids the risk of infection and trauma from mating and the complications of a difficult pregnancy and delivery. Uterine infections can occur in dogs and cats of all ages but may be even more dangerous in older females.
• Eliminates unwanted heats and the annoying behavior associated with the estrus cycle.
• Spayed pets, particularly those spayed before the first heat, have a decreased risk of developing malignant mammary tumors later in life. Spaying helps protect your pet against the risk of ovarian and uterine cancer and uterine infection (pyometra).
• A female dog or cat is unlikely to develop any dramatic improvement in temperament by delaying or not having spay surgery. Similarly, there is no behavioral advantage to breeding or to the experience of delivering and caring for a litter. In fact, the opposite may be true.
• Do not use your pets to educate children about the "facts of life" when there are so many other appropriate teaching references available.
• There is no scientific evidence that your pet will in any way benefit from having a heat and/or litter before spaying. Although hormonal changes after the surgery may temporarily increase her appetite, weight gain can be controlled by adjusting the type or amount of food given.

A few words about neutering your male pet:

Neutered pets make better pets. They stay at home more instead of roaming and getting into fights. Neutered males don't get testicular cancer either. The surgery consists of removing both testicles. We urge you to have it done.

Considering the emotional and physical stress endured by cycling females, spaying a pet is an act of kindness. Unless you are sincerely convinced that you want your dog or cat to have a litter, we recommend this important procedure. Feel free to call us if you have any questions.