Degenerative Osteoarthritis-results
from destruction of the cartilage that protects the bones
that make up the joint.
Ligamentous Laxity-
is a connective tissue disorder. In
a 'normal' body, ligaments (which are the tissues that
connect bones to each other) are naturally tight in
such a way that the joints are restricted to 'normal'
ranges of motion. This creates normal joint stability.
If muscular control does not compensate for ligamentous
laxity, joint instability may result. The trait is
almost certainly hereditary. In the case of extreme
laxity, or hypermobility, affected individuals often
have a decreased ability to sense joint position, which
can contribute to joint damage. The resulting poor
limb positions can lead to the acceleration of degenerative
joint conditions. Many hypermobility patients suffer
from osteoarthritis.
Ligaments are fibrous tissues
that connect bone to bone. There are dozens of ligaments
in the body and almost every joint has at least two
of these structures. Ligaments are short, elastic bands
of fibers composed of collagen (protein) bundles. Collagen
diseases commonly arise from genetic defects that affect
the biosynthesis, assembly, postranslational modification,
secretion, or other processes in the normal production
of collagen. Ligaments have cells for maintaining the
bundles, and some blood vessels. Nerve fibers are found
in these bundles, which play an important role in proprioception—the
ability to know where the limbs are in space, even
without looking at them. When the ligaments are no
longer taut, this sense can be lost, causing clumsiness
and instability.
Osteogenesis Imperfecta-is
a heritable connective tissue disorder. Osteogenesis
imperfecta (OI) is a genetic condition found in both
humans and dogs and is characterized by extremely
fragile bones and teeth. This bone fragility can
result in the bones breaking with no apparent caus..
OI can also cause weak muscles, brittle teeth, a
curved spine and hearing loss. The cause of OI is
a genetic defect that affects how the body produces
collagen, a protein that helps make bones strong.
Collagen is the main protein of connective tissue
in animals. The mutation which causes OI has been
located in Dachshunds and is located on dog chromosome
21.Usually humans and animals inherit the faulty
gene from a parent. Sometimes, it is due to a mutation,
a random gene change. OI can range from mild to severe
and symptoms vary from one individual to another.
When a young dog is evaluated for multiple fractures
with no apparent cause, osteogenesis imperfecta (OI)
is suspected. Radiographic findings showing multiple
bone fractures in various stages of healing is used
to confirm the diagnosis of OI.. Clinical signs consist
of pain, spontaneous bone and teeth fractures, loose
joints, and reduced bone density on radiography. Primary
teeth are extremely thin-walled and brittle.
In dogs, OI has been reported in Golden Retrievers,
Collies, Poodles, Beagles, Norwegian Elkhound, and
Bedlington Terriers.
(http://www.gopetsamerica.com/dog-health/osteogenesis_imperfecta.aspx)
(http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000579)
Ehlers-Danlos Syndrome
("Rubber Puppy Syndrome") - refers
to a group of inherited disorders that affect collagen
structure and function. Genetic abnormalities in
the manufacturing of collagen within the body affect
connective tissues, causing them to be abnormally
weak.
Hypermobility type
Excessively loose joints are the hallmark of this EDS type, formerly
known as EDS type III. Both large joints, such as the elbows
and knees, and small joints, such as toes and fingers, are
affected. Partial and total joint dislocations are common,
and particularly involve the jaw, knee, and shoulder. Many
individuals experience chronic limb and joint pain, although
x rays of these joints appear normal. The skin may also bruise
easily. Osteoarthritis is a common occurrence in adults. EDS
hypermobility type is inherited in an autosomal dominant manner.
There are two major clinical diagnostic criteria for EDS hypermobility
type. These include skin involvement (either hyperextensible
skin or smooth and velvety skin) and generalized joint hypermobility.
At this time there is no test for this form of EDS.
(http://medical-dictionary.thefreedictionary.com/Ehlers-Danlos+syndrome)
An important characteristic of dominant gene mutations
is that they can have variable expression. This means
that some individuals have milder or more severe symptoms
than others. In addition, which systems of the body
the mutation affects can vary as can the age at which
the disease starts, even in the same family. Another
important characteristic of dominant gene mutations
is that in some cases, they can have reduced penetrance.
This means that sometimes a n individual can have a
dominant mutation but not show any signs of the condition.
(http://www.healthsystem.virginia.edu/uvahealth/hub_cancer/adi.cfm)
Cutaneous
Asthenia-Cutaneous asthenia (literally,
weak skin) is part of a group of hereditary disorders
characterized by skin that is unusually stretchy
and droopy. It is caused by a genetic mutation
that is passed from parent to offspring. More than
one genetic disorder is suspected, but this condition
cannot be determined by skin and tissue samples,
it is diagnosed through observation.
This condition is also known as Ehlers-Danlos syndrome,
a disease characterized by deficient levels of collagen,
the protein molecule necessary for providing strength
and elasticity to the skin and ligaments, along with
much of the rest of the body. Collagen is the “glue” that
holds the body together. A lack of collagen will result
in abnormal collagen synthesis and fiber formation.
Dogs affected with this disorder suffer from painful
dislocation at the joints due to the instability of
the ligament fibers that hold the bones to each other.
The ligaments stretch with movement, but without the
elasticity needed to return to their form they stay
stretched out, allowing the bones to pop out of their
connective joints. This creates a painful physical
environment for the sufferer of cutaneous asthenia.
The primary cause of this medical condition is heredity.
It is caused by a genetic mutation that is passed from
parent to offspring, and can be either dominant – from
both parents, or recessive – from only one parent.
(http://www.petmd.com/dog/conditions/skin/c_multi_cutaneous_asthenia#)
Canine Demodicosis-a
disease caused by a mite (Demodex canis) that lives
deep in the hair follicles. This mite is transmitted
from the bitch to the offspring during suckling and
is found in small numbers on all dogs. It is believed
that these mites may initially cause problems in dogs
due to an immulogic or genetic disorder. This can occur
in two "general" ages of dogs. One group
is less than 2 years old at onset--junvenile demodicosis.
The other age group affected is older dogs-adult onset
demodicosis.
Congestive heart failure is
a condition in which the heart can't pump enough blood
to the body's other organs.
The heart keeps working but not as efficiently as it should.
As blood flow out of the heart slows, blood returning to the
heart through the veins backs up, causing congestion in the tissues.
Often swelling results. Sometimes fluid collects in the lungs
and interferes with breathing, causing shortness of breath, especially
when lying down. Heart failure also affects the kidneys' ability
to dispose of sodium and water.
(http://www.americanheart.org/presenter.jhtml?identifier=4585)
Atresia of nasolacrimal
puncta is a condition where the holes on the
inside of the lower eyelids (puncta) are too small
or closed so tears spill over the lid instead of
draining to the nose.
Distichiasis is
a disorder where extra eyelashes grow inside the eye
lid. There is often a second row of eyelashes; this
can be a complete row or just a few lashes. These abnormal
lashes tend to fall out and regrow, just as normal
lashes do. Districhiasis indicates that there is more
than one lash growing out of a follicle - commonly
seen with distichiasis. This is presumed to be hereditary,
but the mode of inheritance has not been determined.
If not treated, it may lead to corneal ulcers and infection.
Allergy is one
of the most common conditions affecting dogs. In the
allergic state, the dog's immune system overreacts
to foreign substances (allergens or antigens) to which
he is exposed. These overreactions are manifested in
three ways. The most common is itching of the skin,
either localized (one area) or generalized (all over
the dog). Another manifestation involves the respiratory
system and may result in coughing, sneezing, and/or
wheezing. Sometimes, there may be an associated nasal
or ocular (eye) discharge. The third manifestation
involves the digestive system, resulting in vomiting
or diarrhea.
There are five known types of allergies in the dog:
contact, flea, food, bacterial, and inhalant. Each
of these has some common expressions in dogs, and each
has some unique features.
(http://www.sniksnak.com/doghealth/allergies.html)
Atopic dermatitis is
known by many names including: canine inhalant
dermatitis, inhalant allergy, allergic inhalant
dermatitis, atopy and canine atopic dermatitis.
It is a condition in which the immune system is
hypersensitive and reacts abnormally (allergic
reaction) to various substances in the environment
such as pollens, molds or dust mites. These substances
are called allergens. Dogs may either inhale the
allergens or contact them through the skin.
The
condition is clearly inherited but the exact mode
of transmission is not yet clearly established.
A combination of factors are necessary though for
atopy to develop. It occurs when a dog who has
the genetic make-up for allergy is exposed to specific
allergens to which he shows an abnormal immune
response.
(http://www.canadawestieclub.ca/health/derm.html)
Glaucoma is
a condition of the eyes occurring in dogs and cats
much the same as in human beings. More common in dogs,
it appears glaucoma has an inheritable tendency. Cocker
Spaniels, Poodles, Beagles, are a few breeds which
can carry the trait for glaucoma.
(http://www.vet4petz.com/articles/glaucoma.htm)
The following information is from http://www.napoleon.org.uk/health/poodlehealth.htm
Progressive Retinal
Atrophy a disorder of the eye in which the
light cells in the retina wither and die due to insufficient
blood supply. the disease progresses Gradually, results
in blindness and has no known cure. Its onset in
the Poodle is between 5 to 6 years old. The presence
of PRA can be detected by ophthalmascopic examination
by a veterinary ophthalmologist.
Corneal Dystrophy -
Corneal dystrophies" are diseases of the cornea
that are bilateral, non-inflammatory and inherited.
Legg-Calve'-Perthes -
a disorder in which non-inflammatory a vascular necrosis
of the femoral neck and head result in one of both
of a young dog's rear legs becoming lame. Irritability
and pain are other primary symptoms. Some dogs recover
and function without treatment, but in severe case
surgical removal of the femur head is indicated.
Patella Sub-luxation -
or slipped kneecap, a condition in which the patella
slides in and out of the groove where it is normally
held in place by ligaments. This causes hopping or
favoring of the leg until the kneecap slips back
into place. In some cases, in can be surgically corrected.
Epilepsy -
a neurological disorder marked by recurring seizures
that follow episodic, abnormal discharges of electrical
impulses by nerve cells in the brain. As in humans,
it is controlled with drugs such as Phenobarbital
or Dilantin.
Hypothyroidism -
a condition resulting from an inadequate production
of thyroid hormone. Also treated with drug therapy,
its symptoms include a coarse, brittle coat that
falls out, thickening and discoloration of the skin,
lethargy, obesity, mental slowness and irregular
heart cycles.
Cryptorchidism -
or undescended testicle, a condition in which one
or both testicles are retained in the abdominal cavity.
Hormone injections, given to stimulate testicular
descent, sometimes are successful. When the treatment
is unsuccessful, removal of the testicles is recommended
because cryptorchid testicles may become cancerous.
Mitral Valve Disease -
The heart consists of 4 chambers - 2 atria and 2
ventricles. The atrioventricular (AV) valves ensure
that the blood flows from the atria to the ventricles
when the heart beats. A defect in the mitral valve
(the left atrioventricular valve) causes backflow
of blood into the left atrium, or mitral regurgitation.
Less commonly, a narrowing or stenosis of the valve
can be identified. Because of the leaky valve, the
heart is less efficient at pumping blood to the body.
Autoimmune Hemolytic Anemia
(AIHA) - A decrease in the number
of red blood cells (RBC's) or the amount of hemoglobin,
resulting in a decrease in the oxygen- carrying
capacity of the blood.
Cushings Disease -
This is a disease that occurs from the overproduction
of cortisone by the adrenal glands.
Addisons Disease -
A disorder caused by a deficiency in adreno cortical
hormonesmost commonly occurring in young to middle
aged dogs.
Liver Shunts -
Liver Shunts are abnormal vascular connections between
the hepatic portal vein and systemic circulation. Such
anomalies cause blood in the gastrointestinal tract
to be diverted past the liver, there by limiting the
liver's vital functions in metabolism and detoxification
of compounds.
Entropian -
An eye condition in which the eyelids are grown inward,
causing the eye lashes to come into contact with the
eye itself.
Autoimmune Disease -
If a dog has an autoimmune disease, the immune system
mistakenly attacks self, targeting the cells, tissues,
and organs of a dogs own body. A collection of immune
system cells and molecules at a target site is broadly
referred to as inflammation.
Lupus - This
is a rare disease of the immune system. In this disease,
the immune system forms antibodies against the nuclear
component of its own cells.
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