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The normal oestrus cycle can be quite variable between dogs, although it should be constant for a particular individual. Typically seasons occur about twice a year, with a range of 4 - 12 months. They normally last 3 weeks, with the bitch being most fertile around day 10 – 12. A thin red vulval discharge is present for the first half of the season, changing to a light creamy discharge around the time of ovulation. As bitches get older the time between seasons can get longer and each season may become shorter, with less discharge. However if the seasons become longer, if there is an abnormal vulval discharge or even if they stop altogether then an internal reproductive disease is probably present, which could prove life threatening if not treated. Problems of the ovariesCystic ovaries – these are quite common in older bitches, particularly those dogs that have not had a litter. Sometimes the signs are just that the bitch stops having seasons. Alternatively there can be a persistent watery red discharge after a normal season with thickening of the vulva. Male dogs may be interested in her though she wont want to know. Occasionally the cysts become so large that they can cause distension of the abdomen. Ovariohysterectomy (spaying) will always be curative. Ovarian tumoursFortunately these are quite rare in the bitch. When they do occur they can be benign or malignant. Signs can be very variable but any older bitch having abnormal seasons, (often longer than normal), a swollen or discharging vulva, or mammary enlargement should raise suspicions. With benign and early malignant tumours surgery is generally curative, although malignant growths can quickly spread to the kidneys, liver and lungs.
Problems of the uterusPyometra
The disease starts as cystic endometrial hyperplasia – or swelling and thickening of the uterine wall, each time a bitch has a season. If the dog has a litter this extra tissue is stripped out to some extent. If they don’t, the abnormal tissue becomes very susceptible to infection. Hormonal changes during the season also weakens the immune system, so that bacteria find it easy to get into the uterus. Infection then starts to build, normally leading to an illness 4 – 8 weeks after the season has finished. The signs of pyometra can be very variable – classically the bitch will have an increased thirst, go off her food, start vomiting, have a high temperature, and a bloody, smelly discharge will be produced from her vulva. However in a lot of cases, the dog will just show a general malaise and lethargy. These patients may require blood tests, x-rays, an ultrasound scan or even exploratory surgery to diagnose the condition. Pyometra is a very serious infection. The uterus fills up with pus, releasing toxins into the blood which damage the kidneys and cause vomiting. The uterus greatly increases in size (see photo above, of uterus, approx 15 times larger than normal, and full of pus), and can even rupture internally making the bitch suddenly much worse. If left untreated pyometra can become rapidly fatal as the kidneys and other internal organs are irreparably damaged. The treatment required will depend on how severe the conditions is. In most cases intravenous fluids are given to correct dehydration and injections of antibiotics are used to help fight the infection. In all cases the bitch should then be spayed to remove the cause of the problem. A quick recovery usually follows. If the bitch is not spayed, she will initially improve to some extent with the antibiotics although the infection will quickly return once she is off medication, while all the toxins in her system will continue to damage her kidneys. Uterine TumoursThese are fairly unusual tumours and can be benign or malignant. If caught early enough spaying the bitch will be curative. Unfortunately malignant tumours can spread to the liver and lungs, and prove fatal.
Vaginal problemsVaginal prolapseThis is seen in some bitches during the season. The floor of the vagina becomes very red and swollen, to the extent that it flops out through the vulval lips to appear as a red distended balloon. It is not a particularly painful condition although the bitch may traumatise the swelling and introduce infection. The swelling will also stop successful mating. The prolapse can be removed, although frequently a lot of haemorrhage occurs. Alternatively, the bitch can be given hormones to stop the season, or the season left to finish naturally, when the swelling will go down. However, the dog should be spayed to prevent a recurrence. Vaginal tumoursThese tumours are normally benign, sometimes occuring multiply, and grow under hormonal control from the ovaries – similar to fibroids in humans. They may just cause a swelling at the back end of the dog, but if they appear higher up the vagina, they interfere with urination and cause constipation. Spaying the bitch will stop the tumours growing, and in some dogs the tumors even partially regress. However if the tumours are very large, they may need to be resected. As most are benign and do not spread, removal will cure the problem.
Problems with the mammary glandsFalse pregnancyOwners often wonder why their dog is having a false pregnancy. It is in fact a normal occurrence to help the survival of pups in a pack situation. In the wild it is only the top dogs of a pack that actually produce litters. Some of the other bitches produce milk, so that they can help with feeding the pups. Unfortunately these false pregnancies can be a bit upsetting in the home environment. False pregnancies can affect bitches of any age. Signs generally start 4-9 weeks after a season is finished. In most cases there will be enlargement of the mammary glands, and milk is easily expressed, although some dogs don’t actually lactate at all. There are usually changes in the behaviour of the dog – they can become very ‘clingy’, possessive over toys, or unsettled. They may start making a nest for themselves and some dogs go off their food. Occasionally aggression can occur. The condition usually resolves in 3 – 4 weeks. However if there are severe behavioural problems or a lot of milk production, treatment can be given. ‘Galastop’ is a medication that inhibits the hormone responsible for milk production. Spaying a bitch after the false pregnancy has finished will prevent recurrence.
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