Plant-based calcitriol reduced the requirements of calcium and available phosphorus in broiler chicken diet

1. An experiment was conducted to study the effects of supplementing calcitriol (CT) on performance and bone mineralisation in broilers (1-42 d) fed a calcium and available phosphorus (Ca-aP)-deficient diet. The CT (10 mg/kg 1,25-di-OH-VitD3) was derived from Solanum glaucophyllum leaf.2. A control diet (CD) with the recommended (Cobb 400) levels of Ca (9.4, 9.2 and 8.8 g/kg) and aP (4.5, 4.2 and 4 g/kg, respectively, in starter, grower and finisher) was prepared. Six experimental diets were prepared, which include two reduced diets (RD) formulated with 80% (R80) and 70% (R70) of the recommended levels of Ca and aP. Both RDs were supplemented with three levels of CT (0, 1 and 2 µg/kg). Each diet was offered ad libitum to 10 replicate pens (198 × 122 cm) containing 25 male broilers each from 1 to 42 d of age.3. Body weight gain (BWG) and feed conversion (FCE) were recorded bi-weekly. The degree of hock joint deformity was measured as leg abnormality score (LAS) and concentrations of Ca and P in serum were analysed on d 43. The right tibia was analysed for total ash, Ca and P in tibia ash.4. The BWG was not affected by either the reduction of Ca and aP or the supplementation of CD to the RD. Similarly, FCE was not affected by reducing the Ca and aP to 80%, while at 70%, the FCE was reduced compared to the CD group. Supplementation with CT significantly improved the FCE similar to the CD group during the starter phase and overall period (1-42 d).5. The LAS increased and bone minerals (as tibia ash and its Ca and P contents) reduced in broilers fed both RD. Supplementation with CT at 2 µg/kg significantly reduced LAS and improved the bone mineral variables similar to those fed the CD.6. Dietary Ca and aP levels can be reduced to 70% of the dietary recommendations for the broiler breed with supplementation of calcitriol at 2 µg/kg without affecting the performance and bone mineralisation.