pets disease

Cats afflicted with cardiomyopathy suffer from impaired circulation, which in turn can lead to a condition known as arterial thromboembolism. This disorder is characterized by large blood clots that form within the left side of the heart and pass into circulation, only to lodge within one or more blood vessels within the body, usually at the point where the large aorta divides into two smaller arteries that supply the hind limbs.
When such a clot restricts blood flow to the back legs, pronounced hind limb weakness results. The hind paws might feel cold to the touch, and the clear nails might take on a bluish hue. As the muscles of the hind end are deprived of blood and oxygen, they become firm and painful to the touch.
Diagnosis of arterial thromboembolism is based on clinical signs and physical exam findings. Ultrasound can be used to assess the condition of the heart and to identify thrombi still within the organ. A total absence or partial reduction in hind limb pulse is diagnostic of a thromboembolism as well.
Treatment for arterial thromboembolism is difficult at best. Surgery is usually unrewarding, and the existing heart disease in these cats makes them high anesthesia risks. Medical therapy can be somewhat effective if instituted within a few hours of onset. This involves administering drugs designed to dissolve the blood clot, prevent further thrombi from developing, and restore normal blood flow.
Prognosis for a full recovery is guarded, simply because of the preexisting heart disease and because of chronic pain and tissue damage caused by the temporary loss of oxygen. However, with physical therapy and attentive nursing care, many cats experience at least partial functional restoration in 1 or 2 months. Obviously, management of the preexisting cardiomyopathy is necessary as well.

Veterinarians are often confronted by frustrated pet owners claiming that their pet is going deaf! Now, whether this is a valid claim or rather an actual ploy conceived by a defiant subject will not be known until a thorough ear examination is performed. A pet’s apparent inability to perceive sounds can result for a number of reasons.
First, there might be impedance to the sound waves traveling through the ear. An external ear canal clogged with wax and debris can certainly be the culprit, as can constrictive swelling of the ear canal caused by otitis externa. Torn or ruptured eardrums can also diminish the effective transmission of sound waves to the middle and inner ears.
Interestingly, some researchers feel that a dog’s eardrums are not altogether necessary for efficient conduction of sound waves; rather, sound waves permeating the bony, air-filled tympanic bullae directly fulfill a major portion of this conductive function. Regardless, researchers do know that sound waves must pass through the middle ear cavity before reaching the inner ear, and that fluid or inflammation secondary to otitis media can lead to diminished hearing.
Besides interference with the transmission of sound waves, deafness in dogs and cats can also be caused by developmental defects or damage involving the actual nerve endings within the inner ear. Congenital nerve deafness has been reported in some breeds, including dalmatians, collies, and rottweilers. Nerve deafness can also be inherited in some cats. This type of induced deafness is seen primarily in white cats with blue eyes.
Certain drugs, such as the aminoglycoside antibiotics, are well known for their adverse effects on the hearing function in dogs and cats. Chronic, untreated bacterial and fungal infections within the middle and inner ears can undoubtedly lead to nerve deafness, as can certain viral organisms.
Diagnosis of nerve deafness is based on history and special hearing tests. One such test, the brainstem auditory evoked response test (BAER), measures the brain’s response to auditory stimuli and is quite helpful in the detection of hearing defects, determining the extent of any defect, and pinpointing its location.
Unfortunately, no known treatment exists for true nerve deafness. Hearing aids designed especially for dogs are now commercially available, and may help improve hearing in select instances. Most deaf pets will adapt to their condition with time. However, because of inherent dangers associated with environmental hazards, deaf dogs and cats should not be allowed outdoors unless closely supervised or maintained on a leash and harness.

The integrity of the eyelids is vital to protect the eyes from environmental hazards. Any disruption or alteration in the normal lid anatomy can place vision in jeopardy. And certain masses involving the lids can do just that if they become large enough.
Chalazions are masses involving the eyelid that originate from the small meibomian glands that line the edge of the lid. They result from a buildup of secretion within the glands due to blockage of the ducts leading from the gland. Chalazions appear as yellow to white swellings beneath the conjunctiva on the inner lid margin. Puncturing or incising these to remove the trapped contents will afford a cure.
Hordeolums are pus-filled masses caused by infections within the meibomian glands or hair follicles lining the lid margin. As with chalazions, these can be punctured and expressed to help speed healing. Topical or systemic antibiotics are also used to eliminate infection.
Tumors that affect the eyelid can be very serious due to the inability to remove them surgically without disrupting the integrity of the lid. Sebaceous gland adenomas are common lid tumors, especially in older dogs. Others include adenocarcinomas, papillomas, and melanomas. As an alternative or adjunct to surgical removal, radiation therapy, chemotherapy, or cryotherapy (freezing) can be used as well, depending upon which type of tumor is involved.

Retinal degeneration and disease can be a cause of blindness in dogs and cats. For instance, progressive retinal atrophy (PRA) is a hereditary condition that can strike middle-aged to older dogs and produce blindness over a period of several months to years. Breeds that are predisposed to this condition include Gordon setters, Irish setters, poodles, Norwegian elkhounds, Labrador retrievers, collies, cocker spaniels, and malamutes. Characterized by a slow degeneration of the receptor cells composing the retina, progressive retinal atrophy (PRA) in its early stages often leads to nightblindness in affected dogs. These dogs tend to fear or shy away from poorly lit areas. As progressive retinal atrophy (PRA) progresses, it eventually causes the pupils to remain dilated and fail to respond to light, causing complete blindness.
Retinal function may also be partially or completely lost due to underlying disease or injury. For example, glaucoma affecting an eye can place so much pressure on the blood vessels supplying the retina of that eye that secondary retinal degeneration results. Sudden acquired retinal degeneration (SARD) is another nonhereditary condition that can cause blindness in dogs, yet its exact cause remains a mystery. Interestingly, this disease is often accompanied by an increase in thirst and in appetite in those dogs so affected. Infectious diseases, such as ehrlichiosis and Rocky Mountain spotted fever, and fungi can also adversely affect the region of the retina where the optic nerve exits, leading to inflammation and subsequent loss of vision. In addition, neoplasms such as lymphosarcoma can infiltrate the retinas of dogs and cats and inhibit retinal function. Finally, trauma, immune-mediated diseases, and certain toxins can cause retinal injury and lead to blindness.
Diagnosis of retinal disease and degeneration is made using history, physical exam findings, and information obtained from an ophthalmic examination of the retinas themselves. In addition, an electroretinogram, which measures the electrical activity taking place within the retinas, will provide a definitive diagnosis of retinal degeneration and retinal blindness. If a disease condition such as glaucoma, infection, neoplasia, or toxicity is suspected, other diagnostic testing procedures specific to these conditions may be required as well to confirm a diagnosis.
Unfortunately, there are presently no known treatments for progressive retinal atrophy (PRA) and Sudden acquired retinal degeneration (SARD), and the prognosis remains grave for the restoration of sight in affected dogs. Other diseases involving the retina may respond favorably to treatments specific for the particular disorder; however, it
must be remembered that the longer such treatments are delayed or neglected, the greater the chances are of permanent loss of vision.

Glaucoma is a condition characterized by an increase in fluid pressure from the aqueous humor within the eye(s). In the normal eye, pressure and aqueous levels are maintained at a constant plateau by the continual drainage of excess aqueous humor out of the eye through tiny ports (drainage angles) located where the edge of the iris meets the cornea. If this drainage is obstructed or altered in any way, a rise in pressure within the eye can result. Unfortunately, even short-term rises in this pressure can lead to irreversible damage if not detected and treated in a timely fashion.
Conditions such as a buildup of inflammatory material within the eye, luxation of the lens due to trauma or cataracts, and synechia, where the iris “sticks” to the lens orcornea, can all effectively prevent the normal drainage of the aqueous humor from the eye.
Heredity is also thought to play a role in some cases of glaucoma in dogs, with basset hounds, beagles, and cocker spaniels having a higher incidence of the disease due to improper development of the drainage angles. In addition, a predisposition for lens luxation has been identified along family lines for many of the terrier breeds, predisposing them to glaucoma. Finally, allergies and overactive immune system responses are also thought to be important precursors to glaucoma in dogs and cats. Clinical signs of a glaucomatous eye include a marked redness affecting both the conjunctival tissue and the sclera; a blue, hazy cornea; a dilated, unresponsive pupil; and apparent blindness due to the pressure the fluid is placing on the optic nerve. In instances where the glaucoma has been present for quite some time, enlargement of the affected eyeball might become noticeable, and actual rupture of the cornea could occur.
Diagnosis of glaucoma can be easily confirmed by a veterinarian through the use of an instrument called a tonometer. This instrument, when placed directly on the surface of the cornea, measures the exact pressure within the eye. If the pressure reading is indeed elevated, then treatment should be instituted immediately to prevent lasting damage to the eye.
Treatment for glaucoma is aimed at decreasing the pressure within the eye to an acceptable level as quickly as possible, and then stabilizing this pressure to prevent future increases.
Drugs designed to quickly draw fluid out of the eye and into the bloodstream will initially be used to reduce the pressure within a pet’s eye(s). Other drugs that act by decreasing the production of aqueous humor and by increasing the size of the drainage angles are then prescribed for the long-term management and prevention of recurrence. At the same time, anti-inflammatory medications can be used topically on the eye to clear up any primary or secondary inflammation that might be aggravating the glaucoma.
In instances where a luxated lens is causing the increase in pressure, surgical removal of the offending lens should always be performed. Cryotherapy (freezing) can be used as well. This involves surgically inserting a special needle within the eye and freezing the cells within the eye responsible for the production of aqueous humor. With this technique, aqueous production can be reduced by up to 30 percent in some patients.

In addition to intussusception, other items can obstruct normal flow through the gut and result in clinical signs, such as lethargy, vomiting, and black, tarry stools, and abnormal posture. Swallowed foreign bodies (such as bones, rubber balls, and stones), tumors, fungal infections, and herniations are all capable of causing either partial or complete obstructions if large or extensive enough. Unless the obstruction is relieved in a timely fashion, usually through surgical means, loss of blood supply to the affected portion can occur, resulting in the death of that portion of bowel, systemic infection, and shock.

Periodontal disease, or tooth and gum disease, is one of the most prevalent health disorders in dogs and cats. Studies have shown that most canines show some signs of this disease by 3 years of age. Early signs can include tender, swollen gums, and, most commonly, bad breath. More importantly, though, if left untreated, periodontal disease can lead to secondary disease conditions that can seriously threaten the health of affected pets.
It all begins with the formation of plaque on tooth surfaces. This plaque is merely a thin film of food particles and bacteria. Over time, however, plaque mineralizes and hardens to form calculus. Owners who lift up their pet’s lip and glance at its teeth, especially near the gumline, might notice brownish to yellowish buildup of calculus on the outer surface of the teeth.
Calculus tends to accumulate worse on the outer surface of the large fourth upper premolars and on the inner surfaces of the lower incisors and premolars. This is because canine saliva is conducive to calculus formation, and the ducts from the salivary glands empty into the mouth at these particular sites. Buildup of this substance tends to be worse in smaller breeds of dogs, such as miniature poodles, Yorkshire terriers, Maltese, and schnauzers. In fact, it is not at all unusual for some of these dogs to start losing teeth by 4 to 5 years of age without at-home preventive dental care.
Along with these breed predispositions, diet can play an important role in the development of periodontal disease. For instance, moist foods high in sugar content promote plaque formation much more readily than do the dry varieties. In addition, diets containing too much phosphorus (such as all-meat rations) have been linked to periodontal disease.
Certain underlying disease conditions might also promote periodontal disease as a side effect. For example, hypothyroidism can lead to gingivitis and dental complications associated with it. Periodontal disease can also occur incidentally with tumors involving the gum tissue and/or teeth.
Pets suffering from periodontal disease can exhibit a diverse selection of clinical signs. Early periodontal disease might be marked only by a decreased appetite due to swollen, painful gums. Pet owners often complain of bad breath in their pets, and might notice signs of gagging or retching as secondary tonsillitis sets in.
As the disease progresses, these signs might worsen, and other symptoms, such as gum recession, gum bleeding, and tooth loss, might arise. Infected teeth that do not fall out can form abscesses, marked by sinus infections, nasal discharges, and/or draining tracts appearing on the face.
But the damage caused by periodontal disease doesn’t stop there. Bacteria can gain entrance into the bloodstream by way of the teeth and gums, seeding the body with infectious organisms. In advanced cases, these bacteria can overwhelm the host’s immune system and set up housekeeping on the valves of the heart. The resulting valvular endocarditis in turn can lead to heart murmurs and eventual heart failure. Besides the heart, the bacteria that gain access to the body because of periodontal disease can lodge in the kidney, causing infection, inflammation, and acute damage. Over time, signs related to kidney failure might develop in affected pets.
Early cases of periodontal disease can be treated by a thorough scaling and polishing of the teeth to remove the offending calculus. This scaling needs to be professionally performed under sedation or anesthesia to ensure complete removal of the calculus under the gumline.
Using special instruments to hand-scale a pet’s teeth at home without anesthesia is not only dangerous but also highly ineffective at cleaning the teeth where it counts the most, up under the gumline. Furthermore, such scaling, if not followed by polishing, will leave etches in the enamel covering of the teeth that can serve as foci for future plaque and calculus buildup.
Antibiotics will also be prescribed for dogs and cats suffering from moderate to advanced periodontal disease to combat the associated bacterial infection. Teeth that are excessively loose within their sockets serve only to propagate infection, and should be extracted. For infected teeth that are still deemed viable, a root canal can be performed as a salvage procedure. See Chapter 4 for prevention tips to help protect pets against the adverse effects of periodontal disease.

The administration of certain antibiotics to a pregnant dog or cat can result in yellow-stained dentin within the teeth of her offspring. The same holds true for adolescents administered these drugs prior to eruption of their permanent teeth. Although this staining has no effect on the health of the teeth, it can be unsightly and detrimental in the show ring.
Calculus buildup can certainly discolor teeth so affected. If allowed to persist on a long-term basis, the tooth surface can often take on a yellow hue, even after the calculus has been removed. In these instances, the complete removal of the calculus is far more important than any discoloration left behind.
As mentioned previously, a brownish discoloration to the teeth could be the result of enamel hypoplasia. Enamel restoration procedures can be employed to deal with this problem.
Finally, a bluish-gray discoloration to a tooth is indicative of inflammation within the pulp cavity, warranting endodontic management if the tooth is to be saved.

Diseases and disorders affecting the teeth or oral cavity interfere with a pet’s ability to prehense and process food for digestion. In addition, other general signs associated with conditions involving these areas usually include increased salivation, swallowing difficulties, bad breath, gagging, and decreased appetite.

Once the gastrointestinal system is on the mend, and all vomiting has been brought under control, a good level of nutrition is required to counteract any malnutrition induced by the disease. Bland diets that are easily digested are prescribed until complete healing of the stomach and/or intestinal linings has taken place. Offering a convalescent pet some type of electrolyte replacement drinks during these first few days can also promote rapid recovery as well. Feeding plain yogurt is also helpful toward repopulating the gastrointestinal tract with non-pathogenic bacteria.

The final threatening factor that arises when acute gastroenteritis strikes a pet is dehydration. Pets suffering from vomiting and/or diarrhea can quickly become dehydrated as a result of water loss through the bowels. Since inflamed bowels cannot regulate water absorption as they do when they are healthy, any fluid intake that indeed occurs will usually pass right out of the body via vomiting and/or diarrhea without being absorbed.
In fact, the disruption of normal motility and distension occurring within the affected bowel can actually attract and draw water right out of the body and into the intestinal lumen. As a result, pets that have become dehydrated or are on the verge of dehydration due to gastroenteritis require intravenous fluids to correct the dehydration occurring within the body’s cells, at least until the gut has healed sufficiently to resume these functions once again.

Fractures or trauma to the cartilage supporting the pinna of the ear can lead to the accumulation of blood and serum within the affected flap. These aural hematomas cause the pinna to swell, sometimes to enormous sizes. In the majority of cases, the fluid accumulation occurs on the inside portion of the earflap.
Researchers don’t know what precipitates many cases of aural hematomas, but they do have a few suspicions. Since these hematomas are often accompanied by otitis externa, many feel that the trauma induced by scratching and shaking the head predisposes to aural hematomas, especially in those dogs with pendulous ears. Still others suspect that an overactive host immune system is the culprit behind this disorder. Regardless of the cause, aural hematomas are painful and irritating, and need to be surgically drained as soon as possible after initial appearance.

Entropion
Entropion is an ophthalmic condition in which the eyelids roll inward, allowing lashes and hair to irritate the surface of the eyes. The condition is inheritable, or it can occur secondary to other types of eye irritation (spastic entropion) or eyelid injury. Congenital entropion has a high incidence in chow chows, shar-peis, English bulldogs, poodles, and rottweilers.
Signs of entropion include excessive tearing, squinting, constant rubbing of the affected eye(s), excessive redness to the eye(s), and a noticeable inward roll to the eyelid, especially the lower lid.
If a pet is suffering from entropion, surgical treatment might be essential to prevent lasting damage to the surface of the eye(s). Some puppies afflicted with this disorder might outgrow it as they mature; hence, surgery is usually delayed in these young animals until they are at least 6 months old, unless the damage to the eye is severe.
In the meantime, topical lubricants designed to protect the corneas can be used on a daily basis in these patients. In some pups, especially sharpeis, temporary eversion of the offending lids with sutures implanted in the skin of the lids can also help prevent complications until they outgrow the entropion or are old enough for the surgery.
Entropion surgery involves the removal of a flap of skin just beneath (lower lid) or above (upper lid) the inverted lid. Suturing close the resulting gap of skin will then provide enough tension to roll the lid back out. In many instances, more than one surgery is necessary to achieve just the right amount of eversion.
After surgery is performed, care must be taken to prevent the dog from irritating the incision line and causing swelling. Hospitalization for a few days after the procedure is performed will help reduce this occurrence.
Because of the inheritable nature of this disorder, all dogs affected with entropion should be neutered to prevent its passing to future generations. When selecting a new pet, especially one that falls into the high-risk category, owners should examine the pup’s parents closely for any signs of entropion or for evidence that surgical correction has been previously performed.

Ectropion
Ectropion is the exact opposite of entropion; it is the outward rolling of the eyelid(s), which exposes the pink conjunctival lining within. As with entropion, this condition is inheritable, with cocker spaniels, St. Bernards, and bloodhounds having a high incidence. Facial nerve paralysis, such as that seen secondary to otitis media, can also result in ectropic lids.
Mild cases of ectropion usually cause no problems whatsoever in affected individuals. Moderate to severe cases are often accompanied by conjunctivitis, excessive lacrimation, and eye discharges. Keeping the eye(s) clean and free of discharge on a daily basis using saline solution or medicated drops or ointments will help keep minor cases of ectropion under control. For more extensive involvement, surgical correction designed to release the tension placed on the skin of the eyelid, allowing it to roll back to its correct position, might be required.

The third eyelid of dogs contains a gland that might occasionally become inflamed and protrude over the edge of the third eyelid, producing a classic “cherry eye” appearance. Certain breeds such as the cocker spaniel, Lhasa apso, Pekingese, and beagle seem to be more predisposed to this condition than others.
In the past, treatment for a prolapsed gland of the third eyelid involved complete surgical removal of the gland. However, researchers agree that the gland might play an important role in tear production; hence, complete removal of the gland might predispose a pet to keratoconjunctivitis sicca. As a result, newer surgical procedures involve removal of only a portion of the gland, or actually tacking down the prolapsed portion of the gland to the inner surface of the third eyelid.

While pancreatitis means inflammation involving the pancreas, hepatitis involves inflammation of the liver. Contrary to popular belief, not all cases of hepatitis are infectious and contagious in nature. There can be numerous noninfectious causes of liver inflammation as well. Some of these include diabetes mellitus, heart disease, accidental poisonings, starvation, and cancer.
Hepatic lipidosis is a common type of liver dysfunction in cats that has baffled researchers for years. It is characterized by an extensive infiltration of the liver by fatty tissue that, in essence, crowds out the normal liver cells and interferes with normal liver function. It is seen in all ages of cats, and the exact cause of this condition is unknown, yet obesity and/or prolonged periods of food deprivation due to loss of appetite are thought to increase the body’s utilization of fats for energy, the metabolism of which is carried out in the liver.
As an organ responsible for metabolism of the multitude of nutrients absorbed from the intestines, and detoxification of poisons and drugs circulating in the blood, it is remarkable that the liver is normally very resistant to injury or breakdown resulting from its normal day-to-day functions. Unfortunately, because of this heartiness, clinical signs of liver inflammation seldom appear until serious damage to liver function has already taken place.
Like so many other diseases affecting the gastrointestinal tract, acute flare ups of hepatitis can cause loss of appetite, vomiting, diarrhea, and fever in affected dogs and cats. One unique sign often seen with hepatitis, both acute and chronic, is jaundice, or icterus. Jaundice, caused by elevated levels of bile pigments in the bloodstream, is characterized by a yellow discoloration of the skin, mucous membranes, and the liquid portion of the blood.
Other clinical signs that can result from chronic, long-term hepatitis and liver disease include a fluid buildup within the abdominal cavity (ascites) due to increased resistance to blood flow through the liver, bleeding tendencies, and anemia. Seizures and other neurologic disorders can also appear with advanced cases as blood levels of ammonia are allowed to build up.
Diagnosis of hepatitis is based on clinical signs, elevated serum levels of liver enzymes, and/or the demonstration of an enlarged liver on radiographs or ultrasonography. For those more subtle cases, special liver function tests and even biopsies might be required to confirm a diagnosis of hepatitis or discover its cause.
Treatment objectives for hepatitis and liver disease are aimed a teliminating the injurious agent and its harmful effect on the liver tissue and at promoting healing of the affected tissue. In cats with hepatic lipidosis, this means force-feeding them if necessary. The liver is one of the few organs within the body that can actually regenerate itself after injury, provided, of course, that the source of the injury is dealt with properly.
If vomiting is a problem, intravenous fluids might be needed until the stomach settles down enough for oral ingestion of food and water. An easily digestible diet with high biological value (available through veterinarians) is ideal for dogs and cats suffering from a liver disorder. Oral antibiotics designed to eliminate ammonia-forming organisms are useful for those cases exhibiting neurological signs. Ascites can be treated with diuretic drugs and by reducing the amount of sodium in the pet’s diet.
Finally, in chronic cases of hepatitis, steroids might be warranted to increase appetite and to counteract the loss of protein that can occur with liver disease. In addition, certain drugs for liver disease designed for use in humans are being used in animals with variable success.

Inflammatory bowel disease (IBD) is actually a group of chronic digestive disorders characterized by the infiltration of the walls of the bowels with inflammatory cells, leading to abnormal wall thickening and irregularities. IBD has been recognized as a significant cause of chronic vomiting and/or diarrhea in both dogs and cats. As far as the etiology of IBD, research to date has failed to uncover an exact cause. Many veterinarians believe that bacterial and/or dietary proteins may stimulate an autoimmune type of reaction in these pets. This reaction, in turn, manifests as a buildup of immune cells on and within the surfaces coming in contact with these proteins.
The classic clinical sign associated with IBD in cats is chronic vomiting. Often misdiagnosed as hairballs, vomiting induced by IBD usually occurs intermittently over months to years, gradually worsening and increasing in frequency with time. In addition to vomiting, bloody diarrhea and abdominal pain are also clinical signs seen in both dogs and cats suffering from IBD. In cats, lymphosarcoma is not an uncommon sequela to severe cases of IBD that cannot be controlled through medical means.
Diagnosis of IBD is made through the use of a thorough history, physical exam findings, radiographs of the abdomen, and more specifically, biopsy samples from affected portions of bowel. Diagnostic techniques such as these will help differentiate this condition from other disorders that may cause similar clinical signs, including foreign bodies, pancreatitis, tumors, and bowel obstruction.
Treatment for inflammatory bowel disease employs the use of drugs designed to reduce the inflammatory response, as well as medications designed to locally suppress the immune system response within the gut. Administration of these medications may be required on a longterm basis to control this disorder. Since food allergies are thought to be an underlying cause in some instances, most treatment regimens for IBD also employ rations that are hypoallergenic in nature.
Unfortunately, a complete cure for IBD is rarely possible. However, with appropriate treatment, most cases can be managed enough to allow the affected pet to live a relatively normal life otherwise.

Supernumerary teeth are extra teeth within the mouth. These can be retained deciduous teeth, or can actually be permanents.
Retained deciduous teeth are commonly seen in small dog breeds, including miniature poodles and Yorkshire terriers. In these dogs, the deciduous canine teeth have the greatest propensity for remaining behind. Such retained teeth can crowd the permanent ones, creating abnormal eruption pathways. In addition, because of their close proximity with their permanent counterparts, these extra teeth can serve as niduses for dental calculus buildup and infection. As long as the eruption pattern for the corresponding permanent tooth is not being interfered with, most veterinarians will postpone removal of the retained tooth (teeth) until another elective procedure, such as neutering or teeth cleaning, is performed. However, if the permanent tooth is being interfered with in any way, immediate removal is recommended.
In rare instances, duplicated permanent teeth, consisting of one or two isolated ones, or an entire arcade, can erupt. Removal of these permanent supernumerary teeth is seldom necessary unless they interfere with the normal biting action of the dog. Because of the genetic predisposition of this condition, affected dogs should not be bred.

Malocclusion occurs when the teeth lining the upper jaw fail to line up and fit properly with the teeth of the lower arcade. In the normal bite, the upper canine teeth should rest just behind the lower canines. Disruption of the normal bite pattern can be caused by trauma, improper tooth eruption, and genetics.
Brachygnathism refers to a condition in dogs in which an overbite, or overshot upper jaw, exists. Conversely, prognathism is the term referring to the undershot jaw (underbite). Both conditions are inheritable traits, passed from one generation to another. In fact, prognathism is considered normal for certain breeds, such as pugs, boxers, and bulldogs. Although not life-threatening, these anatomic maladies can interfere with normal biting action and eating, and can predispose to dental and jaw problems in affected dogs. As a result, dogs suffering from distinct overbites or underbites (unless normal for the breed) should be surgically neutered to prevent the propagation of these undesirable traits.
Malocclusion can also result from improperly positioned deciduous teeth creating abnormal eruption pathways for the permanent ones. Dental examination of the deciduous teeth performed on puppies and kittens as early as 8 weeks of age can help identify potential problems. In many instances, simply removing the offending deciduous tooth clears the path for the proper eruption of its permanent successor.
Surgical repair or reconstruction of the jaw can be used to repair trauma-induced malocclusions, which is the most common type of malocclusion seen in cats. Orthodontic correction of brachygnathism and prognathism has been utilized in select cases, yet for ethical reasons, such procedures should be performed only for medical purposes, not for cosmetic gains.

Eardrums can tear or rupture as the result of direct trauma from a foreign body (a twig, cotton-tip applicator, etc.), sudden pressure changes, or, most commonly, as a secondary complication due to otitis externa. Although a serious and painful condition, a torn eardrum will heal quite quickly provided the underlying cause of the perforation is eliminated.
Medications designed for use in the ears must be used with caution if a dog or cat suffers from a ruptured eardrum. Not only can their application be painful, but also, as mentioned previously, certain antibiotics and solutions, if allowed direct access into the middle-and inner-ear chambers, can cause damage to the auditory nerve endings, resulting in deafness. As a result, be certain to follow a veterinarian’s recommendations closely.