Female Dogs in Heat

Female Dog in Heat

The heat period describes the fertile phase (mating season) in the oestrous cycle of female dogs.

Female Dogs in Heat

Although the heat period is an entirely natural process for female dogs, irritation at stains on the new carpet, fear of an unwanted pregnancy or their pet’s strange behaviour can cause many dog owners to worry. Find out here everything you need to know about your female dog’s heat period and how you can both overcome this without any stress.

Many dog owners consider the heat period of their female dog akin to running the gauntlet. They barricade themselves indoors, avoid long walks in the park where many  male dogs “lie in wait” and cover beds and upholstered furniture with old sheets in a state of panic in order to avoid ugly stains. After all, furniture is expensive and most domestic dog owners can probably do without a pregnancy. Relax though: with a few tips and tricks, you can get through this phase without any problems and have no need to fear unwanted offspring. As is so often the case, the better informed you are about how the heat period works and the changes it will provoke in your dog, the less hassle this time will prove for you.

What you should know about the heat period

The heat period describes the fertile phase (mating season) in the oestrous cycle of female dogs. This changes their body, hormone distribution and their behaviour. This natural process affects all female dogs that have reached puberty.

As with us humans, the onset of puberty and the related start of sexual maturity is highly variable with dogs too. When the heat period commences for the first time differs from dog to dog. The dog being of adult age and having reached its full size are decisive factors for the timing of the first period. Whilst small dogs enter heat for the first time as early as six months in age, large-breed dogs often only reach this phase once they are 12 months in age, since they reach adulthood much later. The duration of the heat period is just as variable as the time puberty is reached. Small-breed dogs can be in hear every four months, whilst prototype dogs like Basnejis, Thai Ridgebacks or Dingos only go through heat once a year.

The four phases of heat

Even though the timing and duration of the heat period are very different, the mating season follows the same pattern with all female dogs. The heat period can be divided into four phases:

  1. Pre-oestrus: The start of pre-oestrus can generally be precisely pinpointed, since it is accompanied by highly visible changes to the female dog in question. Its vulva swells and bloody vaginal discharge is secreted. This phase tends to last nine days, but variations between three and 17 days are not uncommon. Even the amount of bloody discharge differs from dog to dog. Whilst it’s hardly noticeable with some dogs, others bleed so much that their owners live in fear of red stains on the carpet and upholstery. A further sign that pre-oestrus is underway is increased interest from male dogs, who suddenly cannot keep away from the female. Even if females still aren’t fertile at this point, they already give off a very “tempting” smell. During this phase, however, they tend to repel and reject the advances of their male suitors. They bark, get out of the way or even bare their teeth if a male gets too insistent

  1. Oestrus: During oestrus, female dogs change their behaviour pattern of rejection, suddenly showing themselves open to and interested in the male’s advances. This is a clear sign that you’re now on dangerous territory, because the female is now fertile and ready to breed. If a male approaches at this time, the female will voluntarily remain standing and wag her tail to the side. Known as “standing heat” for this reason, this phase lasts an average of nine days too. During this period of standing heat, several ovulations occur. The vulva subsides somewhat, vaginal discharge becomes more watery and sometimes more mucous. Should reproduction take place during these few days, the chance of impregnation is high.

  1. Post-oestrus: Post-oestrus begins after around nine days of the oestrus phase. The symptoms of heat such as the swollen vulva and watery discharge gradually disappear. There are now hardly any outward signs of being in heat, but hormones ensure all sorts of changes are occurring inside the female dog’s body. Regardless of whether they were impregnated or not, the corpora lutea produce the hormone progesterone, which encourages the implantation and growth of the embryo in the uterus. Corpora lutea that emerge after ovulation in the ovaries only decompose after nine to twelve weeks. Progesterone level in turn boosts the hormone prolactin. The secretion of prolactin encourages the production of milk, which leads to a false pregnancy.

  1. Anoestrus (rest period): After several weeks of intense hormonal alternations, the sexual hormones even out to a normal level. Progesterone remains at the same level, whilst the oestrogen level only shows slight variations. Anoestrus is the name for the rest period. It lasts several weeks to months and ends with the onset of pre-oestrus, the next heat period. During this phase, the female shows no signs whatsoever of being in heat and is not fertile.

Peculiarities of the first heat phase

The female’s first heat phase during puberty doesn’t usually stick to this fixed sequence. It’s not uncommon for there to be a so-called “quiet heat period” the first time round, in which no external indicators such as discharge can be recognised despite hormonal changes. Hence, it can be the case that the dog owner has no idea whatsoever that its female dog is in heat for the first time. For instance, this often occurs with breeds such as the Beagle, American Staffordshire Terrier, Cocker Spaniel or Miniature Pinschers.

Even so-called “split oestrus” for young females is not uncommon. Here typical signs of the heat phase such as discharge first come about during the pre-oestrus phase, but don’t lead into the oestrus phase during which the dog is fertile. Instead, they initially subside completely. The female only shows fresh signs of pre-oestrus again after a few days or weeks, and this is then followed by oestrus.

When is the heat phase interrupted?

If the heat phase fails to materialise for an adult female, this can be caused by an interruption in ovarian function or adrenal gland hyperactivity. In this case, you should get your dog examined by a vet to be on the safe side. The same applies when the heat phase goes on for an extremely long time, such as the bloody discharge or willingness to reproduce lasting longer than three weeks or the heat period being shortened, meaning that pre-oestrus and oestrus last less than ten days in total.

Do dogs go through the menopause?

In contrast to us humans, dogs don’t go through the menopause, as there is no period in which menstruation does not occur. Hence, female dogs will be in heat for the rest of their life. However, some females that are older than seven years in age only go through the heat phase once a year. The heat intervals can also be extended in old age – but they do not disappear entirely.

How can I recognise my dog’s fertile period?

A female dog’s fertile period generally lasts five to seven days, but since the transitions from phase to phase are fluid, the “heat days” can’t always be precisely pinpointed. An indication is the change in the colour of the blood from dark red to a light, watery discharge. This doesn’t give 100% certainty though, since there are also female dogs that reproduce despite their blood being dark red. A further possible way of recognising the fertile period is to test tolerance reflexes. During standing heat, females indulge males, raise their tail to the side and the vulva gently rises. It is no crystal-clear signal, as there are also female dogs that react to this reflex outside the heat period.

Only a vet can give you precise information on the fertile period by determining the moment of ovulation. If you find out once after how many days of pre-oestrus actual oestrus itself starts, it will be at the same time for future heat periods. It’s important that you recognise when exactly pre-oestrus has started, because only this way can you count the days until oestrus.

How do I avoid a pregnancy?

Even if you can’t pinpoint your dog entering oestrous to the day, there are a few signs to indicate that the heat phase is underway. Caution should be exercised at the very latest when bleeding becomes more watery and your female dog remains standing when males attempt to make a pass. In this situation, you generally still have enough time to separate the two dogs from one another. Very few males pounce on the female straight away, but instead begin with “foreplay”. However, there are of course others that get down to business quickly – in such cases, your timely intervention is required. Order your female dog to sit and stand behind her. Hold the male dog at a distance and wait until its owner takes it away on its lead.

How to avoid stressful situations?

In order to avoid such situations from the outset, you should be aware of a few things during the heat phase. Go out for walks at times when there are as few dogs around as possible. Avoid parks or open spaces where you know there are lots of dog running around (off the lead). Only let your female off her lead during the heat phase if she follows you faithfully and put the lead back on as soon as another dog approaches you. As well, try to distract her on walks with intensive games. At home, ensure that the love-crazed dogs in your neighbourhood have a hard time entering your property. You’re best off keeping the house doors and garden gates closed.

Do I need heat diapers/dog nappies?

These are dog nappies that females can wear during the heat period. This is recommended if they bleed heavily during pre-oestrus and red stains cannot be avoided despite their innate self-cleaning ritual. Caution: these nappies are not a chastity belt and cannot prevent pregnancy.

Should I get my female dog spayed?

To avoid the stress of the heat period, many dog owners seize the opportunity get their pet spayed. In contrast to sterilisation, spaying avoids the heat period entirely. There are definitely some advantages for such medical intervention. Females often become calmer and stop bleeding. Furthermore, the risk of certain types of tumours and cancers, such as uterine cancer, is significantly reduced.

However, there is another side of the story too: spayed dogs often suffer from obesity and the danger of urinary incontinence in old age. An altered fur structure is a side-effect for Cocker Spaniels and Irish Setters after spaying, which leads to the fur felting more and requiring more maintenance. Before you decide to get your female dog spayed, you should closely weigh up the advantages and disadvantages. Take advice from your breeder or vet.

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