Siberian Husky Puppies May Inherit Benign Familial Hyperphosphatasemiia
Siberian Husky puppies and children under the age of 5 share a predisposition for a condition known as benign familial hyperphosphataesemia (BFH). An unfounded spike in their blood alkaline phosphatase (ALP) is the telltale sign. Blood ALP is an enzyme that comes from various tissues but predominantly from the liver and bones.
The culprit of this age-related disorder is genetics. Among those affected, both puppies and children inherit high ALP from their parents. Children with BFH may have ALP values three to 50 times higher than unaffected children their age. Likewise, affected Siberian Husky puppies could have ALP values more than five times higher than normal.
Fortunately, the condition appears to be harmless, and dogs and children eventually “outgrow” high ALP. In the meantime, recognition of the disorder is important.
When dogs are sick, blood testing can be used to help determine the cause. When the ALP level is elevated, it could indicate bone cancer, Cushing’s disease (hyperadrenocorticism) or liver conditions. It also could be a normal reaction to steroid medications.
ALP is an enzyme synthesized by the liver and osteoblasts in bone; elevations in blood ALP can indicate a problem, but it is not very specific. Elevated ALP is one of the most common abnormalities detected on the blood chemistry profile of dogs.
“Veterinarians should consider the age of a dog when evaluating the significance of elevated ALP,” says Michelle Kutzler, DVM, PhD, DACT, associate professor at Oregon State University. “In healthy young puppies, ALP values can be up to four times higher than in adult dogs. In the first week, they are higher due to the dam’s colostrum. Rapid bone growth in puppies contributes to the elevated bone-derived ALP level.”
ALP levels normally peak when puppies are around 3 months of age, and then gradually decline until they are in the normal range around 15 months of age. Giant-breed puppies may not reach the normal adult range until they are 2 years of age.
“When blood testing shows that a Siberian Husky puppy has elevated ALP, it raises suspicion that the dog could have a possible liver- or bone-related illness,” Kutzler says. “Many veterinarians may not be aware that some healthy Siberian Husky puppies have an unusually high ALP level.”
A study1 conducted by Purina scientists examined BFH in 42 related Siberian Husky puppies from eight litters. Puppies with high ALP activity were evaluated at 11 and 16 weeks and compared with their unaffected littermates and other unaffected Siberian Husky puppies of the same age.
The evaluations included:
- biochemical analyses, including electrolytes and isoenzymes of alkaline phosphatase
- ionized calcium concentration
- blood parathyroid hormone concentration
- diet, growth and health performance
- skeletal radiographs
- pedigree information
Although 17 of the 42 puppies tested had markedly high ALP values, they had no other abnormal findings. The mean total ALP activity of these affected puppies was more than five times greater than that of the unaffected puppies.
“These extremely high ALP values would cause concern for the puppies’ well-being,” Kutzler says. “But these puppies’ growth, clinical health, skeletal radiographs, and other biochemical testing data were normal. The increased ALP in five puppies was attributed to bone origin, but no difference in bone characteristics was detected.”
In dogs, as in people, elevated ALP is believed to have an autosomal mode of inheritance. Elevated ALP values should be evaluated in any dog, but in Siberian Husky puppies, veterinarians should consider benign familial hyperphosophatasemia as a possible cause.
1 Lawler DF, Keltner DG, Hoffman WE, et al. Benign familial hyperphosphatasemia in Siberian huskies. American Journal of Veterinary Research. 1996(May); 57(5):612-617.