Ruby Cavalier King Charles Spaniel
Italian researchers find retinal dysplasia and microphthalmia in a family of cavaliers. In a of an oral abstract presented before the European College of Veterinary Ophthalmologists in May 2015, a team of Italian ophthalmologists (Luca Mertel [right], MG Baldini, E Moretti, SP Marelli, A Picchi, M Polli) report on the parents and littermates of a family of cavalier King Charles spaniels. The ruby dam "was affected by multiple distichia and bilateral peripheral tapetal multifocal retinal dysplasia." The black-&-tan sire "had unilateral iris to iris persistent pupillary membranes." Pup #1 (ruby female) "had bilateral multifocal and geographical retinal dysplasia". Pup #2 (black-&-tan male) "showed bilateral microphthalmia".. Pup #3 (black-&-tan male) "had bilateral iris to iris persistent pupillary membranes and unilateral right multifocal and geographical horseshoe-shaped retinal dysplasia." They concluded:"Microphthalmia with lens dysmorphogenesis and normal looking fundi seems to be a feature in the CKCS. Littermates may be affected with varies forms of retinal dysplasia, as in the Akita and the Chow Chow."
Dr. Peter Bedford reports microphthalmos and congenital cataracts are linked in CKCSs. In the of EJCAP Online for the Federation of European Companion Animal Veterinary Associations (FECAVA), UK ophthalmologist Dr. Peter G.C. Bedford summarizes the research in hereditary eye disorders. He states that congenital nuclear cataract may accompany microphthalmos, persistence of remnant pupillary membrane (PPM) and retinal dysplasia in the Cavalier King Charles Spaniel.
Posterior Lenticonus, Cataracts, and Microphthalmia: Congenital Defects in the Cavalier King Charles Spaniel. Narfstrom K, Dubielzig R, J Small Animal Practice 25:669 1984.
Hereditary cataract in the Miniature Schnauzer. K. C. Barnett. J.Small Animal Prac.; Nov. 1985;26(11):635-644. Quote: "Posterior lenticonus, cataract and microphthalmos, as reported here and in the USA (Gelatt et al., 1983b) has also been reported in the Cavalier King Charles Spaniel in Sweden (Narfstrom & Dubielzig, 1984)."
Padgett, G.A., Howell Book House 1998, pp. 198-199, 241.
Ocular Disorders Presumed to be Inherited in Purebred Dogs. Genetics Committee, A.C.V.O. 1999.
Guide to Congenital and Heritable Disorders in Dogs. Dodds WJ, Hall S, Inks K, A.V.A.R., Jan 2004, Section II(199).
Breed Predispositions to Disease in Dogs & Cats. Alex Gough, Alison Thomas. 2004; Blackwell Publ. 44-45.
Ophthalmic Disease in Veterinary Medicine. Martin C.L. Manson Publ. 2005.
Charles L. Martin. Manson Publ. 2009; page 475, table 15.1. Quote: "Presumed Inherited Ocular Diseases: Table 15.1: Breed predisposition to eye disease in dogs: Cavalier King Charles Spaniel: ... Microphthalmia with multiple ocular anomalies".
. Peter G.C. Bedford. 2010. RVC. Quote: "There are two types of disease which affect the eye of the brachycephalic breeds and both are directly or indirectly related to genetic predisposition. First and by far the commonest are those conditions which are due to be conformation of skull and are related to the exophthalmos which is the common feature of these breeds. Second there are those conditions which have been unwittingly bred into some brachycephalic breeds in the pursuit of desired breed characteristics. In this lecture I will present an overview of all the diseases that the small animal practitioner is likely to encounter in the brachycephalic breeds of pedigree dog. The fourteen breeds I have included for discussion are the Affenpinscher, Boston Terrier, Boxer, Bulldog, Cavalier King Charles and the King Charles Spaniels, (mesaticephalic) French Bulldog, Griffon Bruxellois, Japanese Chin, Lhasa Apso, Pekingese, Pug, Shih Tzu and Tibetan Spaniel. Corneal Lipid Dystrophy: The term applies to the characteristic cholesterol and triglyceride deposits in the superficial corneal stroma seen most commonly in the Cavalier King Charles Spaniel. It is clinically benign and seldom affects vision to any noticeable degree. Hereditary Cataract: Hereditary cataract is seen in the Boston Terrier and the Cavalier King Charles Spaniel. Microphthalmos (MoD): Again the American literature suggests that microphthalmos (MoD) may be inherited in the Cavalier King Charles Spaniel."
. Peter G C Bedford. EJCAP Online, Genetic/Hereditary Disease and Breeding. Autumn 2013;233(3):23-41. Quote: "Congenital inherited disease: ... Congenital Cataract: Cataract is defined as any opacity of the lens and/or its capsule. Congenital inherited cataract always involves the central embryonic and foetal nuclear portion of the lens, whilst those lens fibres which make up the cortex usually remain transparent. Thus congenital nuclear cataract is often described as stationary, with the effect on the dog’s sight being dictated by the extent of the opacity. Such patients may be managed long term by using long acting mydriatic drugs, but when cortical involvement occurs lens removal may prove necessary. The condition occurs as a recessive trait in the Miniature Schnauzer and it may become established as an inherited entity in the Old English Sheepdog, the Golden Retriever and the West Highland White Terrier unless breeders respond adequately to early findings in these breeds. Congenital nuclear cataract may also accompany microphthalmos, PPM and retinal dysplasia in breeds like the Bloodhound, the Cavalier King Charles Spaniel, the Cocker Spaniel, the Dobermann, the Golden Retriever, the Old English Sheepdog, the Rottweiler, the Rough Collie, the Standard Poodle and the West Highland White Terrier as part of a multi-ocular defect (MOD).