Serum markers of bone metabolism in dogs.

OBJECTIVE

To establish reference values for a panel of serum markers of bone turnover in dogs of various ages.

ANIMALS

Dogs in 4 age groups (0 to 1 year; 1 to 2 years; 3 to 7 years; > 8 years).

PROCEDURE

Serum concentrations of the carboxyterminal propeptide of type-I procollagen (PICP) and the aminoterminal propeptide of type-I procollagen (PINP), both markers of type-I collagen synthesis (hence, bone formation), were measured by use of commercial human radioimmunoassay kits. Serum concentrations of the carboxyterminal cross-linked telopeptide of type-I collagen (ICTP), a marker for type-I collagen breakdown (hence, bone resorption), also were measured by use of a commercial human radioimmunoassay kit. Serum osteocalcin (OC) concentrations and alkaline phosphatase (ALP) isoenzyme activities were measured by use of techniques developed specifically for dogs.

RESULTS

As expected, the highest values for all of the markers were found in young dogs (< 12 months old). Concentrations of OC and ICTP decreased with age, and were lowest in dogs > 8 years old. Total ALP and bone-specific ALP activities initially decreased with age, then increased in dogs > 8 years old.

CONCLUSIONS AND CLINICAL RELEVANCE

Serum markers of bone turnover may be useful diagnostic and prognostic tools for management of dogs with musculoskeletal disorders.