Animalia Life

The Breed History
It is thought that early in the 1800s, a shipwreck of a British ship off of Maryland landed the breed progenitors in the US. Some out-crossing to Otterhound, and Curly and Flat-coated Retrievers may have occurred, but because of the exceptional retrieving talent, this line was highly valued. They are thought to have originated in Newfoundland-Labrador from the same stock as the Labrador Retriever. They received AKC recognition in 1885.

Breeding for Function
Bred to fetch ducks from the cold water, this breed is still used for this purpose and Working Dog certificates are awarded to those dogs that continue to show excellent retrieving skills. They are also land retrievers, and are also a popular companion dog. They excel at tracking, obedience, and guarding. They are also being trained as therapy dogs. Their hallmark is exceptional endurance under the most severe conditions (cold water, wind). Some natural haircoat oiliness helps them to repel water away from the skin and undercoat.

Physical Characteristics
Height at Withers: female 21-24" (53-61 cm), male 23-26" (58.5-66 cm).
Weight: females 55-70 lb (25-32 kg), males 65-80 lb (29.5-36.5 kg).
Coat: The double water-resistant coat is brown, sedge grass, or dead grass colored to blend with their surroundings. The outer coat is wavy and dense with coarse, glossy hairs and the inner coat is soft, wooly and oily. Small white spots may be found on some dogs.
Longevity: 10-12 years.
Points of Conformation: A broad skull, large jaws and soft mouth provide the capacity for bird fetching. The face has a moderate stop, and eyes are yellow to amber. The ears are high set, triangular and medium length and pendulous, with medium leather. This medium sized dog has a deep thorax, and is well muscled with strong bones, though not coarsely built. The topline is level or mildly ascending towards the rear. Working dogs would normally have any rear dewclaws removed; fronts as well.

Recognized Behavior Issues and Traits
Reported breed characteristics include: These dogs are noted for their intelligence, alertness, willingness to press on in harsh conditions, and their even-tempered and gently protective natures. The presence of either shyness, or any overly protective tendency is strongly discouraged in the breed. An experienced owner, or one with breeder or other guidance may be best to handle training these somewhat dominant dogs. They may be, on average, more independent, territorial and aggressive than other retrievers. They require regular activity and exercise. They require average grooming, and are low shedders. They do best outside of city.

Normal Physiologic Variations
The coat tends to be oily so bathing 3 or 4 times a year is recommended as a minimum.

Drug Sensitivities
None reported

Inherited Diseases
Hip Dysplasia: Polygenically inherited trait causing degenerative joint disease and hip arthritis. OFA reports 20.8% affected.
Elbow Dysplasia: Polygenically inherited trait causing elbow arthritis. OFA reports 5.6% affected.
Progressive Retinal Atrophy (PRA): Autosomal recessive progressive rod cone degeneration (prcd) form. Age of onset between 4-7 years, eventually causing blindness. Optigen testing reports 4% affected, and 30% carrier in Chesapeake Bay Retrievers. CERF does not recommend breeding any Chesapeake Bay Retriever with PRA. A direct genetic test is available.
Exercise Induced Collapse (EIC, Dynamin 1 Mutation): An autosomal recessive disorder of muscle weakness, incoordination and life threatening collapse accompanied by hyperthermia after just five to fifteen minutes of intense exercise or excitement. After 10 to 30 minutes of rest, most dogs return to normal. Limited genetic testing reveals 11% carriers and 1.3% clinically affected homozygous Chesapeake Bay Retrievers. A direct genetic test is available.
von Willebrand's Disease (vWD): Severe, autosomal recessive bleeding disorder, Type III von Willebrand's disease occurs in the breed. A genetic test has not been developed.
Patella Luxation: Polygenically inherited laxity of patellar ligaments, causing luxation, lameness, and later degenerative joint disease. Treat surgically if causing clinical signs. Too few Chesapeake Bay Retrievers have been screened by OFA to determine an accurate frequency.

Disease Predispositions
Hypothyroidism: Inherited autoimmune thyroiditis. 12.9% positive for thyroid auto-antibodies based on testing at Michigan State University. (Ave. for all breeds is 7.5%).
Distichiasis: Abnormally placed eyelashes that irritate the cornea and conjunctiva. Can cause secondary corneal ulceration. Dorn reports a 1.53x odds ratio in Chesapeake Bay Retrievers versus other breeds. Identified in 5.98% of Chesapeake Bay Retrievers CERF examined by veterinary ophthalmologists between 2000-2005.
Allergic Dermatitis: Inhalant or food allergy. Presents with pruritis and pyotraumatic dermatitis (hot spots). Reported at a frequency of 4.5% in the 2004 ACC Health Survey.
Umbilical Hernia: Congenital opening in the body wall from where the umbilical cord was attached. Reported at a frequency of 4.3% in the 2004 ACC Health Survey. Unknown mode of inheritance.
Cataracts: Posterior cortical, axial, triangular opacities are the major inherited cataract in the breed, though anterior, capsular, and nuclear cataracts also occur. Age of onset around one year of age. Identified in 4.23% of Chesapeake Bay Retrievers CERF examined by veterinary ophthalmologists between 2000-2005. Early reports suggest dominant inheritance with incomplete penetrance. CERF does not recommend breeding any Chesapeake Bay Retriever with a cataract.
Idiopathic Epilepsy: Generalized or partial seizures. Control with anti-seizure medication. Reported at a frequency of 3.5% in the 2004 ACC Health Survey. Unknown mode of inheritance.
Humeral Osteochondritis Dissecans (OCD): Polygenically inherited cartilage defect of the humeral head. Causes shoulder joint pain and lameness in young growing dogs. Mild cases can resolve with rest, while more severe cases require surgery. 50% of cases are bilateral. Reported 7.7x odds ratio versus other breeds.
Cranial Cruciate Ligament Rupture (ACL): Traumatic tearing of the anterior cruciate ligament. The breed is found to be one with an increased incidence. Dorn reports a 2.01x odds ratio in Chesapeake Bay Retrievers versus other breeds. Treatment is surgery.
Persistent Pupillary Membranes: Strands of fetal remnant connecting; iris to iris, cornea, lens, or involving sheets of tissue. The later three forms can impair vision, and dogs affected with these forms should not be bred. Identified in 1.55% of Chesapeake Bay Retrievers CERF examined by veterinary ophthalmologists between 2000-2005.
Gastric Dilatation-Volvulus (bloat, GDV): Polygenically inherited, life-threatening twisting of the stomach within the abdomen. Requires immediate treatment. Reported at an increased frequency in the breed.
Degenerative Myelopathy (DM): Affected dogs show an insidious onset of upper motor neuron (UMN) paraparesis at an average age of 11.4 years. The disease eventually progresses to severe tetraparesis. Affected dogs have normal results on myelography, MRI, and CSF analysis. Necropsy confirms the condition. Reported at a frequency of 0.83% in Chesapeake Bay Retrievers. Unknown mode of inheritance. A direct genetic test for an autosomal recessive DM susceptibility gene is available. All affected dogs are homozygous for the gene, however, only a small percentage of homozygous dogs develop DM. OFA testing shows 45% carrier and 12% homozygous "at risk" for the DM susceptibility gene.
Entropion/Ectropion: Rolling in or out of the eyelids. Can cause corneal irritation or conjunctivitis. Dorn reports a 1.40x odds ratio in Chesapeake Bay Retrievers versus other breeds. Entropion is reported in 0.55% and Entropion in 0.09% of Chesapeake Bay Retrievers CERF examined by veterinary ophthalmologists between 2000-2005.
Adult-onset Hair Loss (Endocrine Hair Loss): Young adult Chesapeake Bay Retrievers present with nonpruritic, non-inflammatory, hair loss affecting the axillae, latero-ventral thorax, flanks, ventrum, dorsum, rump and/or the caudal part of the thighs in both male and female dogs. Hormonal investigations showed increased adrenal and sex steroid concentration in seven cases. Histopathology revealed follicular hyperkeratosis and plugging, follicular atrophy, and occasional melanin clumping with malformed hair shafts. Unknown mode of inheritance.
Anterior Crossbite, Brachygnathism, Central PRA, Prognathism, Retinal Dysplasia, and Wry Mouth are reported.

Isolated Case Studies
Tricuspid Stenosis: A 3-year-old castrated male Chesapeake Bay Retriever was referred for evaluation of tachypnea, exercise intolerance, and cyanosis. On echocardiographs, there was severe tricuspid stenosis and right-to-left atrial-level shunting of blood. Balloon dilation of the stenotic tricuspid valve was palliative.
Lymphangiosarcoma: Case study of a a three-year-old, neutered male Chesapeake Bay Retriever presented for acute swelling of the head, neck, and cranial trunk. Diffuse lymphangiosarcoma involving the superficial and deep dermis and subcutaneous tissue was observed on skin biopsies.

Genetic Tests
Tests of Genotype: Direct test for prcd-PRA is available from Optigen. Direct test for EIC is available from the University of Minnesota Veterinary Diagnostic Lab. Direct genetic test for an autosomal recessive DM susceptibility gene is available from the OFA.
Tests of Phenotype: CHIC Certification: Required testing includes hip and elbow radiographs, and CERF eye examination (after 12 months of age). Optional recommended testing for prcd-PRA, thyroid profile including autoantibodies, and congenital cardiac examination. Recommend patella evaluation.

Miscellaneous
- Breed name synonyms: Chessie - Registries: AKC, UKC, CKC, KCGB (Kennel Club of Great Britain), ANKC (Australian National Kennel Club), NKC (National Kennel Club) - AKC rank (year 2008): 48 (2,463 dogs registered) - Internet resources: The American Chesapeake Club: www.amchessieclub.org/ Chesapeake Bay Retriever Club of Canada: www.cbrcc.ca Chesapeake Bay Retriever Club (UK): www.chesapeakebayretrieverclub.co.uk