Mycoplas

and Reproductive Systems

by Isaac Maeda, DVM

Reproductive problems manifest in various ways from failed breedings to sterility. Though this article was to cover Mycoplasma alone, it is important to realize that infections are just a few of the causes of infertility. Of the many different things which can cause infertility in the dog, a very general and partial list would include
:
1. Anatomy (structure and conformation of the reproductive system)
2. Endocrine (hormornes, thyroid for example)
3. Neoplasma (cancer)
4. Genetic (abnormal genes causing sterility)
5. Enviorment (too hot or too cold)
6. Chemical (certain drugs or toxins)
7 Infection

Infections of the reproductive system can be caused by several organisms. However bacteria, Mycoplasma and Ureaplasmaa are the more notable. Ureaplasmas are similar to Mycoplasmas and for our purposes
will be considered together.

Brucella is a bacteria which can cause abortions, infertility and other infections in the body. The disease it causes is better known as Brucellosis.

In addition, it is potentially contagious to humans. Testing for this organism is via blood screens. Fortunatley, it is not routinely encountered today. Besides Brucella other bacteria can can also create reproductive difficulties. These other bactera, such as Streptococcus and E coli, are tested for by culturing. In the bitch,
anterior vaginal (forward part of vagina next to cerix) swabs taken in anestrus (not in estrus of heat) will yield information on what bacteria are present. Culturing of these swabs involves growing these bacteria, indentifying their type, and testing which antibiotics are most effective against them (sensitivity test). Certain types of bacteria in high enough numbers are considered pathogenic (disease causing).

There are appoximately 15 different species of Mycoplasma of which at least one: Mycoplasma canis (M. canis), is a considered pathogenic in the dog. Some veterinarians have seen abortions, stillbirths, and pyometra (pus filled uterus) in bitches which have M. canis. Though the incidence of these cases are not too high, they are significant.

In the stud dog, there has also been infertility associated with Mycoplasmas. In some cases complete sterility is the end result. It is considered by one theriogenologist (Veterinary reproductive specialist) to be a major infectious cause of infertility in the stud. So why all the ruckus and confusion over Mycoplasma? For one, there are dissenting opinions among theriogenologists as to the significance of positive Mycoplasma cultures. Don't forget that there are all those different species of Mycoplasma, some of which do not cause disease. Moreover, Mycoplasma can be found in normal apparently healthy animals. In addition, the organism can survive in many different areas of the animal including the respiratory and reproductive tracts. Lastly, Mycoplasmas may act alone or in concert with other infectious agents (such as bacteria and viruses) to cause disease. As a result, it may be difficult to tell whether a disease is caused by the bacteria, the Mycoplasma or both organisms together. A good example of this is infectious Tracheobronchitis better known as "Kennel Cough". There are about seven different organisms including Mycoplasmas which have been implicated in the disease. Several different combinations of the agents will suffice in inducing Kennel Cough. No one single agent can be labeled as the only disease producing organism.

Now that everything is as clear as mud and you regret asking me to write this article, what should we do? I feel the following suggestions are reasonable when dealing with the infectious side of reproductive management.

1. Test all breeding animals prior to use for Brucella (Brucellosis)

2. Test (culture) all breeding animals prior to use for Mycoplasma

IF:
A) You are maintaining a Mycoplasma free kennel or are dealing with a Mycoplasma problem. and /or
B) You are doing a workup for problem dogs (infertility, etc.)

3. Do general bacteria cultures as part of the workup on problem dogs.

How is Mycoplasma transmitted? Direct dog to dog transmission is the primary means. Sinse the organism can inhabit both the respiratory and reproductive systems, nose-to-nose and nose to tail contact can transmit the agent.

How is the disease prevented? Unfortunately, no lasting immunity to the organism is stimulated. As a result, even dogs cleared of the infection are still at risk for reinfection. In addition, no vaccines are available to render an animal safe. Thus, the protection scheme you impliment for your kennel will depend largely upon your individual needs. As covered earlier; testing, isolation, treating positives, avoiding contact with other dogs and periodic retesting are the only means of control in a kennel. One last point on control. The disease is usually seen in crowded or high intensity kennels. Apparently large numbers of dogs in close proximity allow the organism to multiply sufficiently to cause disease. More space or lower numbers of animals will aid in control.

To end on a positive note, though some cases are difficult to clear, most will respond to antibiotics. Choramphenicol, tetracycline, and Enrofloxacin are a few of the drugs used against Mycoplasma. Moreover, douches of various antibiotics or disinfectants are often employed in the bitch. Your Veterinarian will be able to design a therapeutic plan for your dog. This is not idle propaganda, drug selection varies with each patient (age, concurrent dsease, pregnancy, etc...) and it would unwise to recommend a single regimen.

In conclusion, there will be more information forthcomming from those in research about this organism. Hopefully, this information will equip us better to deal with Mycoplasma in the future.

No reprints without permission. This is an informational report only. There is no email address for Dr. Maeda