Evaluation of Vitamin D₃-Calcium Therapy in Rachitic Dogs

This study was designed to evaluate the influence of treatment on clinical signs, cortical indices (CI) of radius and ulna (measured radiographically), and serum concentrations of the Calcium (Ca), Phosphorus (P), alkaline phosphatase (ALP), 25-Hydroxyvitamin D and osteocalcin (OC, bone biomarker) in 12 rachitic dogs. The dogs were treated with vitamin D₃ @ 20, 000 IU/kg body weight (BW) intramuscularly at a weekly interval along with daily oral Ca supplementation @ 25 mg/kg BW for two months. Dogs were re-evaluated at 30^th and/or 60^th day post-treatment. Nine apparently healthy dogs were kept as control for comparison of CI and biochemical parameters. Data were analysed by paired and two-sample t-tests. Results showed appreciable improvement in most of the clinical signs within the 1^st month of treatment. When compared to control group, at day 0, serum P concentration did not vary significantly (p<0.05), CI and serum concentrations of Ca, 25-Hydroxyvitamin D and OC were lower (p<0.05), while ALP was higher (p<0.05) in rachitic dogs. Moreover, during the treatment period, serum P concentration did not change significantly (p>0.05) while serum Ca increased (p<0.05) and ALP decreased (p<0.05) from the baseline values. There were significant differences between the pre-and post-treatment values of CI and Ca to P ratio (p<0.05). Serum concentrations of 25-Hydroxyvitamin D and OC increased post-treatment at day 60 (p<0.05). In this study, treatment with vitamin D₃ and Ca stimulated bone remodelling, as demonstrated clinically and by significant increase in the serum concentrations Ca, 25-Hydroxyvitamin D and OC.