Missed heat cycle
Question: Dr. Richards: I raise labs. One of my two young dogs came into heat an usually that brings in the other. That did not happen. I had wanted to breed both unfortunately only one is pregnant. Could there be a medical reason for a missed heat. She is a 3 yr old lab and has had no history of missed heats in the past. She seems healthy. Her last heat was last Nov. her sister came into heat in early May. Her last heat had been in the past Nov. Gayle
This probably doesn't apply, since you were looking for signs of estrus, but many veterinarians who do a lot of reproductive work think that the most common cause of heats that appear to be skipped is simply that they were not observed. Some dogs have very subtle signs of estrus, or the so-called "silent heat" in which the dog goes into estrus but doesn't show signs of it. This is a variation that is considered to be normal. Male dogs are sometimes really good at detecting estrus periods that are not outwardly apparent, so paying attention to the male's behavior can be helpful. Unfortunately, when your other bitch is in heat the behavior of male dogs is going to be altered by that. Receptivity to the males by your dog would be a sign of estrus, though. If your female dogs are aggressive towards males or are dominant in the relationship with them the male may not show interest during a heat period.
In general, if a bitch doesn't have an estrus period for 10 months or more there is a good chance that something is suppressing her reproductive cycle. The most common medical cause for failure to come into heat is hypothyroidism. Other possible causes include hyperadrenocorticism, hypoadrenocorticism, diabetes mellitus, cancer
If it has been less than 10 months since your Lab's last heat period, it is probably reasonable to wait and see what happens. If she comes into heat the problem is solved. If she doesn't then checking for hypothyroidism and the other hormonal diseases may be necessary. A good physical exam may reveal signs of these problems, or other problems, as well. Checking progesterone levels might be a good idea, too. If she did have an estrus period without showing signs her progresterone levels might still be high enough to show that. Another alternative is to have weekly vaginal cytology examinations until there is evidence of an estrus period or until it seems obvious there isn't going to be one.
Mike Richards, DVM 8/7/2001
A "tucked" vulva in greyhound
Question: Hi Dr. Mike, I am a subscriber.
Our 3-year-old female Greyhound has what the vet described as a "tucked" vulva. A "fold" of skin around her vulva traps the urine and she gets a recurring infection. Our previous vet said it was a fungal infection and had us treating her with Dermalone ointment once a day. When there was no improvement (and we had changed vets) the new vet took a swab and found it to be full of bacteria not fungi. We are currently cleansing it once a day with Septisol liquid and placing Neo Predef powder on it to help keep it drier. She was also on SMZ TMP 480 MG for 15 days (1 1/2 pills twice a day). The improvement has been dramatic.
However, the vet said there was an operation that "may" correct the problem. This operation is very expensive but would be worth it if there was some certainty that the problem would be corrected. Have you heard of any statistics relating to the success of this operation? Also, because she is a Greyhound there is a greater anesthesia risk. What do you recommend?
The most common cause of infection around the vulvar folds a deep skin fold that leads to hair rubbing against skin on the other side of the fold. This condition normally occurs in small breed overweight females, especially if they have small or underdeveloped vulva. If obesity is contributing to the problem in your greyhound it can help a lot to institute a weight control program but somehow I doubt that is the case.
There really isn't a good long term way to control the fold infections except for eliminating the folds. It does help to keep the area as dry as possible, which is why NeoPredef Powder (tm) may be helping a lot, as it dries, contains a local anesthetic to reduce the urge to lick the area and an antibiotic and corticosteroid. It is usually not necessary to use oral antibiotics long term. If local treatment is sufficient to control the problem you may wish to stick with it.
If local treatment doesn't work well enough to control the problem long term, then surgery is likely to be the only thing that will help. Surgery is not possible in all cases due to the variations in anatomy between dogs but if your vet feels confident in his or her ability to do the surgery, or has someone that they refer these cases to who is good at them, the outcome is likely to be good. In most cases the infections will stop within a few weeks of successful elimination of the irritated folds. It is a really good idea to be sure that there is not a complicating problem, like urinary incontinence, contributing to the inflammation before doing surgery so that this can be considered in the surgical planning and in follow-up care. I can not find specific statistics on the success rates associated with this procedure and there is room for error in recognizing which dogs can be helped and which ones can't but in general the chance for a good outcome is supposed to be favorable.
Greyhounds are more susceptible to anesthetic problems with some anesthetic protocols, in particular barbituate induction, but this is a well known problem and so alternative induction protocols are usually used and anesthesia is maintained with gas such as isoflurane or halothane. Using a heated surgery table or a water circulating heating pad during surgery also seems to help with the really lean breeds and your vet may also do this.
Mike Richards, DVM 4/3/2001
Suppressing estrus - what about injectable hormones?
I have some questions regarding canine reproductive issues.
I have an intact female English Setter, about 5 years old. For a variety of reasons (she's a purebred and I had planned to have puppies from her, she's a sporting dog and I don't wish spaying to change her behavior, I don't want to put her under anesthesia, and I don't like the invasiveness of the surgery) I did not have her spayed. It appears I will not be breeding her as planned, but I still do not wish to have her reproductive organs taken out entirely via surgery.
I would like to know if there are other viable options to control the heat cycle.
I have a book, "The Book of the Bitch," by Evans and White, that talks about hormone injections that can be used to keep an intact female from having her heat cycles. Unfortunately, they did not elaborate on what the hormones were or give much more information than that.
My vet here in the city (suburban Detroit) doesn't have anything on this. Ovaban and Cheque Drops were all he could come up with; neither is without risk of serious side effects.
The indications from the book mentioned above are that the injections are every 5 or 6 months, and as long as they are continued, the heat cycle is suppressed, with little risk of the side effects of Ovaban or Cheque Drops.
Any clue what they are talking about? If so, can you direct me to some sources on the effects of these hormones?
If this is not a viable option, then is there a less invasive surgery, such as tubal ligation, that can be performed? Can it be done with a less potent anesthetic? And would doing this even prevent her heat cycles?
Thanks in advance. Brandon
I am not aware of an injectable drug, approved for use in the United States, that will suppress estrus. There are several drugs used for this purpose in other areas of the world, including medroxyprogesterone, delmadinone acetate and proligestone. I do not know the brand names for these medications. The articles that I can find on them suggest that the side effects are about the same as those seen with the oral progesterone compound approved in the United States, megestrol acetate (Ovaban Rx). Mibolerone (Cheque Drops Rx) is not a progesterone. It is an anabolic steroid, which doesn't mean it doesn't have side effects, they are just different. The veterinarians that I know who do reproductive work feel that Cheque Drops are safer than Ovaban for long term use but I do not know of studies to support or refute that belief. It is possible that the book is referring to the use of medroxyprogesterone acetate (DepoProvera Rx). I have not found information on the use of this medication but it would almost certainly have the same effects as other progesterone compounds and is not approved for use in dogs.
Mike Richards, DVM 2/27/2001
Heat cycle getting irregular
Question: I am a subscriber to your web page, and would like to ask about dog's heat cycle. I have a 5 year old mix breed bitch (mother a saint bernard) who has had a very regular cycle twice a year. The last two heats however have been very short (only some blood for a 3 or 4 days) and this winter she didn't get it at all. Is this normal for her age dog? Do dogs have a menopause? Otherwise she is in excellent shape. The only other thing that I have noticed is her nose hair getting grey, could this be an indicator of lower hormone level and just simply getting old?
Thank you already, Elisa
Female dogs usually have pretty regular intervals between their heat periods until they reach their "senior" years. At this time, the heat periods tend to have longer intervals between them, but not to completely stop. For really big dogs, the senior ages start around six years of age and for small dogs more like eight or nine years of age.
Some dogs do have changes in their estrus cycles or the length or clinical signs of estrus associated with hormonal problems, usually low thyroid hormone levels (hypothyroidism). Other signs of hypothyroidism include lethargy, weight gain, hair thinning or hair loss, increased susceptibility to skin infections and a long list of other less common problems. I do not associate early graying with hypothyroidism in my practice experience and I can't recall literature references that suggest this occurs.
I think that changes in heat cycles are a reasonable reason to test for hypothyroidism. Your vet can do this for you and also provide more information about the probability of this condition based on physical exam findings.
Mike Richards, DVM 1/26/2001
Lasting effects of using Testoserone in Female Greyhounds
Question: Dear Dr. Mike,
We are currently fostering ex-racing Greyhounds and the little girl we have now has something wrong with her. When she was spayed (2 years ago) they also removed a "penis" she started growing because she was given so much testosterone. Are there any lasting effects of overdosing a female dog on testosterone? I'm leaning towards her thyroid level but am trying to research all possibilities. Thanks for any info. Linda
Using testosterone to control estrus and/or increase strength in female greyhounds seems to be a pretty common practice on the greyhound circuit. Despite this, I could not find a lot of information on the long term effects of the use of testosterone in female greyhounds, or in female dogs in general.
There are some known side effects of using mibolerone (Cheque Drops Rx), a compound related to testosterone that is approved for use in dogs for suppression of estrus. Clitoral enlargement (probably what happened to your bitch) or increase in size in other vaginal tissues occurs fairly commonly. Other side effects are not supposed to be common unless the medication is used long term (greater than two years) but include urinary incontinence, aggression, seborrhea oleosa (greasy skin), increased tear production and liver problems.
Most greyhounds have low thyroxine (T4 levels). This doesn't seem to correlate with other signs of hypothyroidism in the breed. Some vets are starting to think that the administration of testosterone over long periods might be causing this problem, since testosterone is known to suppress total thyroid levels when administered. Whether there is a link between this short term relationship and the longer term suppression is hard to say for sure.
I am sorry that I can not give you a more specific answer.
Mike Richards, DVM 1/23/2001
Primary lymphocytic/plasmacytic vaginitis
Question: Dear Dr. Mike,
Maude's situation is potentially much more complex now. A follow-up visit to her regular vet (for another cystocentesis and an abdominal radiograph) revealed that she has nodules in her "vaginal vault." The recommendation: see an internist for a vaginoscopy. My regular vet also did culture sensitivities of the vaginal smear. As of December 28, her urinary tract infection had cleared up, but the vaginal infection included e-coli (predominantly) and two other sources of bacteria. She was placed on Clavamox for this infection.
The internist ordered a chemistry panel and CBC, as well as an ultrasound, during the first visit. Two slight abnormalities on the ultrasound: a mildly enlarged sublumbar lymph node (which she attributes to the inflammation of the vaginal vault) and a mildly enlarged mottle liver (most likely the result of long-term use of AEDs.)
I scheduled the vaginoscopy for the next day, but the platelet count came in alarmingly low: at 20,000. Another platelet count, the next day, came in at 100,000. And just yesterday, the count was down to 30,000 again. The internist also ran a tick panel: all negative. (All of Maude's previous platelet counts were within normal ranges, to this point.)
The internist pulled Maude off the Clavamox, put her on prednisone (which, of course, can cause both seizures and the pancreatitis she once had). She ordered an ANA test, the results of which will be in next week. We'll do another platelet count in five days.
Of course, we can't go ahead with the vaginoscopy until the platelets bump up. The internist has never seen a case like this and is especially puzzled by the fact that there's no bruising or bleeding given the low platelets. (I will add that Maude had a bloody stool for three days in the middle of the sulfamethoxazole/trimethoprim SS therapy. Now, I realize the drug may have caused the low platelet count/bleeding.)
Maude has also lost 3-4 pounds since September, but her diet is extremely low calorie (Wellness whitefish and potato kibble mixed with vegetables).
The internist has suggested primary lymphocytic plasmacytic inflammation (which I can find no information on) as a possible cause of the vaginal inflammation and numerous possibilities for the low platelet count.
So, I'm trying to make sense of all this. I'd appreciate any thoughts you might have on any aspect of the situation.
I would be willing to bet a lot on the probability that the low platelet count is the result of the use of trimethoprim-sulfa combination antibiotics. We have had at least ten patients who have had this problem. Almost all of these occurred when we used smz-tmp medications for longer than 20 days in the treatment of bacterial skin disorders but it is potentially possible for this problem to occur in a shorter time frame. It almost always responds to a short course of corticosteroids and withdrawal of the medication. There are a lot of other possibilities and it is good that the internist is considering all of them, especially if the recovery is not as rapid as one would expect from a drug reaction and withdrawal of the drug. Hopefully, you will be able to get to the surgery reasonably quickly.
My understanding of plasmacytic-lymphocytic vaginitis is that it is usually associated with irregular reproductive cycles (obviously not in spayed bitches), chronic yeast or bacterial vaginitis (in which case it is hard to say which is the underlying cause), in situations in which there are anatomic defects that lead to urine pooling and vaginal irritation and occasionally it seems to be the primary problem -- but that may just be because there is a problem leading to it that just can't be easily identified. It should respond to correction of the inciting cause or anti-inflammatory medications like corticosteroids, if no inciting cause can be found. It is supposed to be possible to confuse vaginitis caused by herpes virus with plasmacytic-lymphocytic vaginitis since one of the features of both conditions is follicle (blister) formation on the vaginal walls.
The internist may know of better treatments than corticosteroids for primary lymphocytic/plasmacytic vaginitis, or at least alternative treatments, since there is some reason to avoid their use in Maude's case.
I hope that things are already much improved.
Mike Richards, DVM 1/15/2001
Q: Dr Mike - I recently purchased a four month old bloodhound puppy - the sweetest dog in the world. She seems perfectly healthy, but on two occasions when she has squatted down to pee a thick fluid has come out, so thick that it hangs from her vagina. I've only seen it happen twice - the first time I thought it was dehydration. She urinates perfectly fine most of the time - my carpet can attest to that. What's going on? What should I do?
A: You are probably seeing mucous or a mucopurulent discharge from the vulva due to vaginitis. This is pretty common in puppies. It responds well to treatment but tends to come back readily until the puppies reach puberty. There is also a chance of a skin infection in the folds of skin around the vulva and you are correct that there is also some chance of cystitis. It is best to let your vet examine her and get a diagnosis. Vaginitis is not always treated since it doesn't seem to stay away with treatment but the other conditions would require care.
Good luck with this. Mike Richards, DVM
My brother's toy poodle was spayed at the age of 4 months and has been having false heats. She was reopened at the age of about one year and more tissue was removed. She is now 2 years old and she is shaking and seems very out of sorts. She's hiding under the bed, not eating and quivering and her vet thinks she is having another false heat. She is only 2 years old and usually very lively. Are you familar with this problem? She going to the vet tomorrow.
You helped me with my toy poodle Trixie whom I lost last May from high amonia levels and nuerological problems -- she was 17. I miss her so much, but I with the information you gave me I was able to request tests that let me know what was wrong with her.
I look forward to your response. Ann
There is a condition in female dogs and cats known as "ovarian remnant syndrome" in which a spayed female continues to exhibit signs of estrus (heat periods. Usually this occurs because a portion of an ovary was left in the abdomen during the spay surgery. This can happen several ways -- sometimes the surgeon doesn't have a clear view of the ovary for some reason (obesity, not having a big enough incision, bleeding, etc.) and a portion is simply missed, other times it is a piece of the ovary is accidentally dropped as it is removed and reimplants in the abdomen. I have had a couple of patients in our practice that appeared to have small pieces of ovary near the normal ovarian tissue but separate from it. So far we have seen these pieces and removed them but I tend to think that there are times when there is just extra ovarian tissue. Dogs that have ovarian tissue that is not removed during a spay tend to show all the normal signs of heat -- swelling of the vulva, bleeding, attraction of male dogs and often false pregnancy signs. These usually occur at the same interval as other estrus periods, roughly seven months. Cats tend to have normal estrus behavior for their species, too. This can be crying, rolling on the floor, overly friendly behavior and attraction of male cats at about 3 week intervals. The only treatment I know of is to find the ovarian tissue that remains and to remove it. This is easiest to do when the pet is in estrus because the ovarian tissue is active and easier to find.
In a dog that has already had exploratory surgery once I think it would be a good idea to do hormonal testing prior to considering another surgery. Sometimes it is possible to tell that ovarian tissue remains just by testing progesterone levels in dogs but only if the progesterone levels are over 2ng/ml. A hormonal response test that starts with administration of HCG (human chorionic gonadotropin) during estrus behavior and then is followed by measurement of progesterone is more accurate. This test works for cats, too.
The symptoms you are describing do not make me think of estrus behavior, though. I'd be more worried about something causing pain, such as a spinal disc problem or pancreatitis, especially if there are no other signs of estrus. Your sister's vet will look for signs of estrus and probably consider a lot of other possibilities if they are not present.
Mike Richards, DVM
Q: Dear Mike, I am writing because we have a dog who seems to be having some problems. We are currently living and working in China. We bought the dog here as a puppy. The man we bought her from couldn't tell us how old she was. Due to our limited vocabulary in Chinese, we can't really take her to a Chinese vet. Could you help us please??
At first, we noticed bleeding from the vaginal area so we presumed that this was probably normal. But now it has been 8 days, and the swelling of the vulva is increasing. Also, the discharge is now more clear & oozy-looking whereas it started as bright red blood. Today we noticed that the nipples (or whatever you call them on a dog?) have also increased dramatically in size. She does not appear to be behaving abnormally though she frequently will rub her bottom on the ground. We do not believe that she has had any contact with any male dogs. She is strictly a house dog. Appetite & such are good. If this is heat, it's her first one and we're just ignorant dog-owners. How long does it usually last?? How frequently does it occur?? Any assistance you could give us would be appreciated.
Sincerely, K. F.
I am sorry for the delay in replying. We had problems with your email, only part of it was transferred to my account and Michal just couldn't get the rest to me until we decided we were trying too hard and she just cut and pasted it to me.
Anyway, I think that it sounds like your dog is in heat. The estral period in dogs normally lasts about 21 days but that can vary a lot. At first there is bleeding with vulvar swelling, then the bleeding slows or stops for a week or so. This period of no bleeding is the fertile period in the heat cycle. Then there is a return of bleeding but usually less than before and that goes on a week or so. The variability in length of heat cycles in bitches is pretty drastic. Some bitches are throught the whole process in two weeks or so and others drag it out for 4 to 6 weeks and sometimes even longer.
If you don't want her to have puppies keep the male dogs away from her!
If you have reason to believe she is not in heat (if she is spayed for instance), please write back with a progress report on the problem.
Mike Richards, DVM
Q: Hi Mike, I'd like some more info on cystic ovaries for a small female dog. Does it cause the vulva also to swell abnormally? Skin baldness, dots, etc. What are the signs of this condition? Im spaying a rescue we got, but she's not in real good shape. She's 5 years, and a medical mess. We are working with a Vet on this, so not to worry. But I was curious, about cystic ovarys...what can you tell me about them? We are also testing for Cushing's & thyroid & auto immune disorders. Appreciate your advice. Take Care, Lesley
A: Lesley- There are several types of ovarian cysts. Only the follicular cysts cause clinical signs that are easily apparent, though. These cysts can produce enough estrogen to cause vulvar swelling and the blood tinged discharge seen when dogs are in heat. This may go on for a long time, since the dog is not really in a heat cycle. In most cases, there is not any desire to mate on the part of the female affected with this condition. I am not aware of hairloss associated with this but estrogens can have this effect so I wouldn't want to rule out that possibility. You are testing for the other differentials that I think of with the signs you describe so hopefully you'll have an answer by now.
Mike Richards, DVM
Q: I currently have a 9 month old german shephard/lab puppy. She has already gone into heat once when she was almost 6 months old and it lasted 6 weeks. Today I noticed that she is licking herself in the genital area and its all swollen down there. I havent noticed yet if she is bleeding, it doesnt appear that way since the blankets she lays on are light in color. Could she be going into heat again? Or do I need to go have her checked out. We planned on getting her fixed before she went into heat again but its only been a month and a half maybe 2 at the most. What should we do??? T.
A: If you are planning on spaying her, the best thing to do is probably to go ahead and do that. Your vet will do a physical exam prior to surgery and will be able to tell you if this is an abnormal return of the heat period (it should be at least 4 months from the last one) or another problem such as pseudopregnancy.
Mike Richards, DVM
Q: Dr Mike Our female german shepard is bleeding in her vagina or whatever you call that part on the dog. Is is a form of menstration because she has not be spayed yet?
A: When female dogs are in heat, there is a blood tinged discharge from the vulva (vagina). If you do not intend to let her be bred it is important to keep her confined where male dogs can not get to her when you are not with her. It is necessary to do this for at least 3 weeks. It is possible to spay a female dog when she is in heat (some vets are uncomfortable doing this but most are willing). If you are planning on getting her spayed anyway you might want to discuss this with your vet.
Mike Richards, DVM
Q: I am inquiring for a friend. She has a 12 month old Mastiff diagnosed with vaginal prolapse. Can you forward any info on this matter, or refer me to a sight where I can obtain more info for her? Thank you, T.
A: Vaginal prolapses are often confused with vaginal hyperplasia, also known as vaginal edema. So the first thing to do is make sure it is a prolapse. Vaginal hyperplasia is treated by removing the protuding tissue surgically. Vaginal prolapse is more difficult to treat if retaining breeding ability is desired -- although this is considered to be a possibly inherited trait so there is some question about the advisability of breeding. Ovariohysterectomy (spaying) is usually curative. Some prolapse will regress on their own as the dog goes out of heat but it probably isn't a good idea to count on that if there is a significant prolapse. I have seen recommendations for treating this with gonadotrophic releasing hormone but do not know of the success rate. Surgical repair by entering the abdomen, retracting the prolapse and suturing the uterus to the body wall may work but it does make future breeding questionable and possibly even dangerous.
Hope this answers your friend's question.
Mike Richards, DVM
Q: Dr. Mike, Our Beagle just went into heat for the first time. How long does she remain in heat? And when will she go back into heat?
A: The average heat cycle for a dog is approximately 3 weeks and since this an an average, some heats are shorter (as little as 7-10 days), others are longer (4 weeks or more). Average times between heat periods is seven months but some dogs can cycle as early as every 4 months, some once a year. Lengths of heat cycles and intervals between cycles are different for each dog but most dogs hit somewhere close to the averages. The first part of heat you will notice bleeding from the vulva, swelling of the vulva, possible increase in urination and the most noticeable, male dogs hanging around the house. During this period (proestrus), females will not allow the males to breed with them although the males will be very persistent. The second part or estrus is the time in which the female will allow the male to breed her and this can last anywhere from 4-21 days. A female, most of the time, will allow most any male to breed during this time. As the female starts to go out of heat or enter diestrus, she will be less willing to breed. Again this stage can last 4-14 days but averages approximately 7 days. The next cycle usually begins about 7 months from the start of the last heat cycle, not the end of that cycle but again this varies from dog to dog. The interval stays the same even if she becomes pregnant. If you do not intend to breed her, you really should consider spaying her. There are many health benefits associated with spaying such as decreased chance of mammary tumors and you will not have to worry about pyometra, metritis or unwanted litters (overpopulation is a big problem - just take a trip to a humane shelter). If you elect to spay her, this can be done during heat but it may be best to wait until the heat cycle is over to decrease the chance of complications.Mike Richards, DVM
Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...