Canine ear

anatomy of the canine ear

1. CANINE EAR Dr.P.Sreenivasa Reddy, MVSc Veterinary assistant surgeon RAHTC, GUNTUR

2. Ear Is An Organ For --- hearing --- balance. It consists of the -outer, -middle, -inner ear.

3. Canine ear

4. outer ear  PINNA (made of cartilage and covered by skin, fur, or hair) EAR CANAL. The pinna is shaped to capture sound waves and funnel them through the ear canal to the eardrum. In dogs, the pinnae are mobile and can move independently of each other. The size and shape of the pinnae vary by breed. The ear canal of the dog is much deeper than that of people and creates a better funnel to carry sound to the eardrum. The average dog can hear about 4 times better than the average person,

5. Middle ear   Eardrum and a small, air-filled chamber that contains 3 tiny bones: the hammer, anvil, and stirrup. It also includes 2 muscles, the oval window, and the eustachian tube (a small tube that connects the middle ear with the back of the nose, allowing air to enter the middle ear).

6. inner ear is a complex structure that includes the cochlea (the organ of hearing) vestibular system (the organ of balance).

7. Physical Examination of the Ear Ear Disorders Are Common In Dogs. Will Examine Routine Check-up . Visually Inspect The Outer Ears, Signs Of Inflammation, Injury From Trauma, Swelling, Secretions, Or Excessive Ear Wax. Otoscope To View The Ear Canal And Eardrum. If An Infection Is Suspected , Tests Will be Performed On Samples Of Fluid For Bacteria or Yeasts. Excessive Overgrowth of Tissue Development of a Tumor is Seen.

8. Further Tests….. X-rays, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Neurologic Tests, Electronic Tests May Be Needed To Confirm Certain Conditions,.

9. Deafness in Dogs Deafness may be…. congenital (present at birth) Acquired as a result of infection, trauma, or degeneration of the cochlea Deafness present at birth can be inherited or result from toxic or viral damage to the developing unborn puppy. Dog breeds commonly affected include the Dalmatian, Bull Terrier, English Cocker Spaniel

10. Acquired deafness may result from blockage of the external ear canal due to long-term inflammation ( otitis externa ) or excessive ear wax. ruptured ear drum or inflammation of the middle or inner ear.

11. Permanent causes of acquired deafness 1.trauma to the hard portion of the temporal bone that surrounds the inner ear, loud noises (for example, gunfire), conditions in which there is a loss or destruction of myelin (the fatty material that surrounds some nerve cells), 2.drugs toxic to the ear (for example, aminoglycoside antibiotics or aspirin), anesthesia , tumors involving the ear or brainstem, and degeneration of the cochlea in aged dogs. 3. Deafness in one ear or partial hearing loss, or both, is possible in some of these instances. Degeneration of the cochlea in aged dogs is the most common cause of acquired deafness.

12. Diagnosis of deafness requires careful observation of the animal’s response to sound. The response to touch, smell, and objects that can be seen must be differentiated from the response to sound. Deafness in one ear is difficult to detect,

13. Primary sign of deafness Failure to respond to a sound, Failure to alert to the source of a sound. Other signs include unusual behaviour such as excessive barking, Unusual voice, Hyperactivity, Confusion when given vocal commands, and Lack of ear movement.

14. Deafness due to blockage of the external ear canal responds to surgical or medical treatment. Deafness due to bacterial infections of the middle and inner ear respond to antibiotic treatment. deafness is due to persistent intense noise or trauma , recovery is unlikely. Hereditary deafness may be eliminated from a breed

15. Symptoms of Dog Ear Infections

16. What Causes Ear Infections in Dogs? The canine ear canal is more vertical than that of a human, forming an L-shape that tends to hold in fluid. This makes dogs more prone to ear infections. Ear infections are typically caused by bacteria , yeast , or a combination of both. In puppies, ear mites can also be a source of infection.

17. Factors that may predispose to ear infections include : Moisture, which can create a prime growing environment for bacteria and yeast Allergies, which lead to ear disease in about 50 percent of dogs with allergic skin disease and 80 percent of dogs with food sensitivities Endocrine disorders, such as thyroid disease Autoimmune disorders Wax build-up Foreign bodies Injury to the ear canal Excessive cleaning

18. Diagnosis Needed for a Dog’s Ear Infections Duration of any symptoms, such as pain, swelling, discharge, and odour If dog has any allergies or other underlying medical conditions If dog is on medication What dog has been eating How often clean dog’s ears and which products to use If trimmed or plucked the hair in dog’s ears Recent activities, such as baths, grooming, or swimming If dog has a history of ear infections, when they occurred, and how they were treated

19. To diagnosis…. Visual assessment to look for signs such as redness, swelling, and discharge Examination with an otoscope, which allows evaluation of the ear canal and eardrum Gentle palpation of the ear to assess level of pain Microscopic examination of samples taken by swabbing the ear Culture of samples from the ear Biopsies or X-rays in severe or chronic cases

20. Can Prevent Ear Infections in Dogs? Excess moisture : dry dog’s ears after swimming and bathing. Cleaning dog’s ears at home   steps for ear cleaning :

21. Next class ….. Disorders of the Outer Ear Ear Infections and Otitis Externa, Otitis Media and Interna Tumours of the Ear Canal in Dogs