Most of these are autosomal recessive so dogs need 2 copies
of the variant to develop disease, one from each parent.
While figures are small, based on a total of 78 village dogs
with publicly available health information.
Degenerative Myelopathy (DM) 15 carry 1 copy (19%) It is
probably fair to assume there are desert dogs out there that are born with 2
copies even though none showed up in this group. Data of many “village dogs”
tested do not show health figures in public profiles, either because only breed
was tested or because that is the default set by Embark and has not been
changed by owners. It is no surprise that with inbreeding of pedigree Canaan
dogs that are derived from a small number of “village dogs” that DM has become
a major issue in the breed. When the breed was established, no genetic testing
was available.
Von Willebrand type 1 – 2 dogs (2.56%)
Factor VII – 1 dog (1.28%)
Collie Eye Anomaly, so called because it was first found in
Collies but more accurately called Choroidal hypoplasia (75% of Collies, 80% of
Stabyhoun and 71% of German spitz have this) – 2 related dogs (2.56%)
Bald thigh syndrome – 2 dogs (2.56%)
Lunderhund Syndrome (affects neuroendocrine cells in the
intestinal tract causing stomach and intestinal problems) – 1 dog (1.28%)
ALT potential low normal 39 (50%) have 1 copy, 17 (21.8%) have 2 copies. This is
not a health issue as such but may mean that a dog with this gene may have a
reference range lower that test books state so could give results that seem to
be in range but are somewhat raised for that dog.
Reference ranges for laboratory tests are often incorrectly called
“normal ranges”. These are typically defined
as the range of values of the median 95% of the healthy population. It is
possible that a given sample even from a healthy individual will show values
slightly outside of the range for some tests. Other factors such as race (breed
in the case of dogs), altitude, age, and sex etc. can also result in variation.
People living at high altitudes will have higher levels of haemaglobin than those
at sea level. Few laboratories establish reference ranges for the local healthy
population. In one laboratory I worked in where the altitude was around 3500
meters up to a maximum 4000 we went to great lengths to establish local
reference ranges. Sadly, some years later with staff changes, no one was aware
of this and when doctors raised questions as to why the laboratory reference
ranges in the computer were not those to be found in textbooks pathology staff
at the time had no answer.
Among a small number of Canaan breed dogs at least 3 have the
genes that increase the risk for Chondrodystrophy and Invertebrate disc disease
developing, 1 has the gene predisposing it to having Urate crystals forming in
the kidney and bladder stones. This does does mean they will have a problem but are at increased risk so need to be watched as time goes on.
Most village dogs that have homes are neutered but Canaan
breeders need to be aware of the potential for genetic issues other than DM
also being present in the breed, as well as the potential for adding some not
yet present when new freeborn dogs are added. Better to test and eliminate all
mutations before they become an issue later.
