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. In particularly 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 with 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.