The Orthopedic Foundation for Animals offers a public database of health results submitted by owners. www.ofa.org
PRA (Progressive Retinal Atrophy) is a family of heritable diseases, as cancer is a family of diseases. PRA causes the death of rods and cones in the eye, beginning with the loss of night vision and then daylight vision. The SWDCA has been at the forefront of working with researchers to identify/develop DNA tests for two separate types of PRA in our breed.
prcd-PRA (progressive rod cone dystrophy) is a late-onset type of PRA that is found in many breeds. Because Portuguese Water Dogs and Poodles also carry prcd-PRA, we knew to look for it in the beginnings of our breed here in the USA. Two dogs (one in the USA and one in Finland) were diagnosed with PRA, and the SWD Club (predecessor to the SWDCA) worked with OFA to determine that we could use the same DNA test that other breeds used to identify prcd-PRA. The trait is passed through a simple-recessive gene, meaning a dog must inherit one prcd-PRA positive gene to bsecome affected. prcd-PRA is a late-onset condition, meaning night vision is lost around 6 years of age, and full vision is lost around 9.
DNA testing for prcd-PRA is available from a wide variety of laboratories. Results (normal, carrier, affected) should be submitted to the OFA.
eo-PRA (early onset) was identified and a test developed in 2020 through the efforts of Dr. Petersen-Jones' lab at Michigan State University and the SWDCA. Night blindness begins at 1 year of age, with full blindness by 2-4. Other breeds have early-onset types of PRA unique to their breeds, so be sure you request the Spanish Water Dog variant of eo-PRA. By January 2021, dogs in the US and the UK have been diagnosed as affected with the condition. It is very likely at least some dogs on every continent carry the genes for eo-PRA.
The Spanish Water Dog Club (UK) has been working on development of a DNA test for glaucoma in our breed. At this time, glaucoma in SWDs is rare in the United States.