Ear Mite: Ear mites, (Otodectes cynotis) is the most common
ear mite of cats but can be a problem for dogs. It usually
lives in the ears and on the head of affected cats or dogs
but it can sometimes live on the body of the cat or dog.
It is contagious and the presence of the mites can cause severe inflammation in affected cat or dog's ears.

Ear mites are not the only cause of ear disease in cats and dogs. Your pet should be examined to determine if ear mites are
present prior to treatment. Whenever treatment for this condition is not working well, other causes of ear disease
should be considered.

In the past it was felt that ear mites did not live well off the pet
but they may be better at surviving in the environment than
we thought. In order to eliminate ear mites it is important
to treat your dog's ears, the haircoat and the pet's
environment for the mites.

There are a number of approved medications for ear mites.
Flea control products that kill adult fleas will kill mites.
These may be used> to treat the haircoat and the house,
according to the product directions. Particularly in stubborn
cases, the use of ivermectin, an experimental drug in cats,
may be justified.

Worms:There are several types of worms, which affect all dogs.

ROUNDWORMS (Toxocara canis, Toxascaris leonina) are the
most common type of worm to infect the animal kingdom.

These worms are usually 2 – 4 inches long, tan or white
“spaghetti-like” creatures with tapered ends.
If a roundworm burden is heavy, a dog may vomit
these worms or pass them (whole) in the stool.
Roundworms can cause vomiting and diarrhea and
can have an effect on a dog’s overall general
health
and appearance. Puppies infected with roundworms
will have a “potbellied” (bloated) look to them.
Roundworms can become so numerous that they can cause
an intestinal blockage and stool cannot pass. As mentioned
above, roundworms are zoonotic (can be transferred to humans)
and can cause an infection known as “Visceral Larva Migrans”,
which may result in possible inflammation of muscle tissue
and blindness.

Anthelmintics (dewormers) that are frequently used to treat
roundworms are pyrantel pamoate, fenbendazole
and piperazine.

HOOKWORMS (Ancylostoma caninium) are blood-sucking
intestinal parasites and have the ability to cause
anemia (and sometimes death) in puppies and adult dogs.
Hookworms cannot be seen by the naked eye,
and the severity of adverse effects will depend on the amount of
worms in the intestine, the animal’s overall health and age.

In humans, hookworms can cause “Cutaneous Larva Migrans”,
commonly called “creeping eruption”. The hookworm larvae
will burrow into the skin of a human’s foot or leg causing
a linear, red lesion, which is intensely itchy. This parasite
has also been known to cause chronic intestinal bleeding,
abdominal pain and diarrhea in small children.

Deworming medications usually include pyrantel pamoate and fenbendazole.

TAPEWORMS: (Dipylidium caninum) are the other parasites
that can be seen by the dog owner. Actually, what the dog owner
will observe is tapeworm segments that have broken
off from the adult parasite attached to the lining of the
dog’s intestinal tract.

These tapeworm pieces are ¼ - ½ inch in length, are usually
white and are usually seen (while still alive) contracting
and expanding around the dog’s rectum or on a dog’s
stool immediately after elimination. Once these segments die,
they will appear like a grain of uncooked wild rice or a
sesame seed and are often found in the dog’s bedding.

The most common route of infection occurs when the
dog swallows a flea that is carrying the parasite’s eggs.
Tapeworms cannot be directly transmitted from dogs to
humans but small children could accidentally ingest
flea larvae or pupae on the floor containing an
immature tapeworm and get a tapeworm infection.

Deworming can be done by either oral medication
or by injection and the most common antiparasitic
agent used is praziquantel another is epsiprantel.

WHIPWORM: (Trichuris vulpis) is one of the less notable
parasites and it cannot be seen by the dog owner.
Unfortunately, this particular parasite is the most difficult to eradicate and control and the symptoms may include severe
diarrhea, flatulence, loss of weight and general overall condition.

The anthelmintic for whipworm most commonly prescribed is
fenbendazole (Panacur).

One note of importance to pet owners, monthly doses of the
common heartworm preventative medication containing
milbemycin oxime will help to keep these parasites under control.

COCCIDA: (Isopora canis) is not a worm, but a single cell
microscopic organism that will cause “havoc” in a
dog’s intestinal tract when present in great numbers.

This protozoa will cause watery diarrhea in young and
susceptible animals that have immature or compromised
immune systems; in some cases, the diarrhea can be
severe enough to be life threatening. Eradication of
this parasite is usually successful with a daily dose
of a sulfonamide antimicrobial agent.

HEARTWORM: (Dirofilaria immitis) is a major parasitic
disease in dogs worldwide. Mosquitoes transmit the disease.
Veterinarians can effectively treat infected dogs,
although preventing your dog from the initial infection is a
far better option.

Development of Heartworm: Canine heartworm develops in the
mosquito. Many different species of mosquitoes
can carry heartworm larvae, so controlling the mosquito is not
a feasible method of prevention.

The life cycle of heartworm is developed in the following stages:

* Adult heartworms reside in the right heart, pulmonary arteries,
and vena cava of the dog.

* The heartworm larvae (microfilaria) are released
into the dog's blood.

* The mosquito ingests the larvae with the dog's blood. After
10 to 30 days, the infective larvae appear in the salivary gland
of the mosquito.

* The mosquito bites another dog, and transmits the infective larvae.

* The larvae migrate in the dog's body for about four months before reaching the dog's heart.

* Worms mature into adults during the next two to three months.

* The heartworm larvae appear in the dog's blood.

Although most cases of heartworm are transmitted by this life
cycle, there are two important exceptions.

The first exception is that larvae can be passed from infected
female dogs to her unborn puppies through the placenta.
However, the larvae will not grow into adult heartworm
because they would need to pass through a mosquito before
becoming infective. Even so, the puppies would be carriers of the
infection. They would also be at risk for a severe reaction
when they start heartworm preventative medication.

The second exception is that the heartworm larvae can be passed
during blood transfusions from donor dogs to recipients.
Consequently, all donor dogs must be clear of heartworm disease
before being used in a transfusion program.

Pathology and Symptoms: Heartworm disease is caused by damage from the
adult worms once they get into the blood vessels of a dog's lungs.
The worms cause the blood vessels to swell and become scarred.
As the blood vessels shrink in diameter, blood flow becomes
increasingly restricted. In the right lung, blood pressure
begins to rise, which causes pulmonary hypertension.
This increased vascular pressure means that the right side
of the dog's heart has to work harder to pump blood through
the lung. Eventually, the pressure will lead to failure of the
right heart.

Many heartworm-infected dogs are free of symptoms.
In dogs without symptoms, any sign of heartworm depend
on the number of worms and the response of the infected dog.
Dogs can be infected with 1 to 250 heartworms at a time.
In general, the higher the number of worms, the more severe
the disease, and the greater the risk for post-treatment
complications. The most common symptoms associated with
clinical heartworm disease are coughing, respiratory distress
and exercise intolerance. In more severe cases, a dog will cough up blood because the pulmonary blood vessels have been ruptured.

If the disease is very severe, the heartworms die and enter the smaller arteries of the lung. If there are dead worms,
a dog's body reacts with an inflammatory response and
numerous blood clots. Severe damage can also cut off blood flow
to the outermost sections of the lung, which causes
the affected area of the lung to be nonfunctional.

Testing for Heartworm: The preferred method for heartworm
screening and diagnosis is antigen testing.
The detection of heartworm larvae is easy,
but the tests can only detect infections with patent larvae.
Unprotected dogs that live in areas where heartworm
is contagious will have larvae-free infections (occult infections).
Occult infections can be produced by one of several reasons,
including the removal of larvae by the dog's immune system,
unisex infections, the presence of immature worms,
or treatment with microfilaricidal drugs. Therefore, a test must be used that detects the immunological antigens produced by adult female heartworms (the males do not release
detectable antigens).

Treatment: Although new drugs have been introduced to make heartworm
treatment less dangerous, it is still a complex process that involves
several steps. Each step must be completed successfully
before beginning the next step of treatment.

Pre-Treatment Evaluation: A pre-treatment evaluation
identifies any risk factors that might increase
post-treatment complications for a dog.

No one diagnostic test can definitively predict which dog
will have a toxic reaction to heartworm treatment, however,
the results of the pre-treatment evaluation are still important.
If a dog tests positive after pre-treatment tests, the larvae are removed.

Before treatment is started, any complications associated with a
dog's heartworm disease (such as heart failure, liver disease,
and clotting disorders) must be managed.
Otherwise, serious or even fatal complications can occur.

Killing the adult heartworms: The drug melarsomine is the newest and most effect treatment for canine heartworm disease.
Dogs that are treated typically receive two intramuscular
injections, given 24-hours apart, in the muscles
next to the lumbar spine. Although there may be some
inflammation at the injection site, it is usually
mild and diminishes within three days. Due to death of the adult
heartworms, there is some degree of post-treatment
blood clots and lung inflammation. Therefore, dogs must be kept quiet for
four weeks after treatment.

Removal of Adult Heartworms: Dogs that are heavily infected
with heartworm are at risk of developing caval syndrome.
This occurs when numerous adult heartworms are
present within the right heart and the main vein that drains
blood from the body back to the heart (the vena cava).
As a result, blood flow into the right side of the dog's heart is greatly decreased.

To avoid fatal consequences, surgical removal of as many
adult heartworms as possible is done immediately.

Once the dog has recovered from surgery, he or she can be
treated with standard drug treatment usually within two weeks.

Assessment of Treatment: The assessment of whether or not a
treatment has been effective is done in two stages.

The first stage determines the clearance of heartworm larvae
three weeks after treatment. The vast majority
of dogs with heartworm larvae are cleared after one treatment.
If they have not been cleared, the dog can be placed on a
heartworm preventative medication. Dogs that
still test positive for larvae should be treated with heartworm
larvae drugs and checked again in another week.

The second stage determines the success of adulticide
therapy. The treated dog should be clear of the heartworm antigen by 12 weeks after treatment.
Up to 20% of treated dogs may still be positive at this stage. A
positive test may simply indicate that
the dog has not yet cleared all of the antigens from its blood.
Tests for the presence of antigens should be done again at regular
intervals. Treatment with adulticide is only needed again if a dog
has persistent and definite positive results
for longer than three months after the initial treatment.

Prevention: Prevention of heartworm infection is much more
preferable than treating it after the fact.
When determining an effective heartworm prevention
program for a dog, several factors are taken into consideration.
These factors include the parasite's life cycle, local transmission season, available preventatives, and health conditions of the dog.

Regular testing for heartworm is a critical part of prevention.
It is the only sure way to determine that prevention has been
successful. Waiting to see if symptoms develop is not an acceptable alternative. Therefore, every dog over six-months
old must be tested before prevention is started.

Puppies should be started on preventative treatment as soon as
it is safe, usually by six to eight weeks. Adult dogs should start
treatment shortly before the local transmission season,
and continue treatment until two or three months after the season.

Dogs that live in warm climates, should be given yearly prevention.