One of the most challenging problems new dog owners face is dealing with a shy or fearful puppy. Occasionally, fear is a manifestation of an undiagnosed medical ailment.
Unrecognized pain
Most veterinarians would agree that unrecognized pain is the number one medical cause of fear in puppies. Orthopedic problems such as elbow and hip dysplasia; damaged cartilage in the knee, shoulder or ankle; intervertebral disc disease of the lower back; and other inflammatory conditions of the bone can cause mild to severe pain that doesn't manifest as an obvious limp.
These dogs may simply be reluctant to go to the dog park, act afraid of a leash, shy away from other dogs or bite in fear of being touched in the area where they feel pain. A good physical exam by your vet and radiographs (X-rays) will usually pinpoint the cause of orthopedic pain.
Visually and hearing-impaired dogs
While most dogs don't like to be surprised by loud noises or quick movements, the deaf or visually impaired puppy may also act excessively fearful if it cannot anticipate the approach of an unfamiliar person or animal. Puppies may cower, fear-bite, urinate, roll over submissively on their side or startle easily if they simply can't hear or see as well as nature intended.
While there are many dog breeds that are affected by congenital deafness, other causes of progressive hearing loss include bacterial or viral ear infections, impacted wax or foreign bodies like grass seeds in the ear canals, trauma and hypothyroidism. The basset hound, shar-pei, Westie, and nearly all spaniel and retriever breeds are commonly afflicted with ear infections. Veterinary attention should be sought if dogs are scratching at their ears, shaking their head excessively, or if a strong odor is detected or debris is seen in the ear canal.
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