Early 1,25-dihydroxyvitamin D3-glycosides supplementation: an efficient feeding strategy against bacterial chondronecrosis with osteomyelitis lameness in broilers assessed by using an aerosol transmission model

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is a leg disorder in broilers leading to huge economic losses, food safety concerns, and animal welfare issues in the poultry industry. The active metabolite of vitamin D₃, 1,25-dihydroxyvitamin D_3, plays pivotal roles in mineral homeostasis, bone health, and immune systems which are essential for protection against BCO. Thus, we hypothesized that supplementation with a Solanum glaucophyllum-derived source of 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃-glycosides) would be an effective measure to control lameness. Here, we report the optimum concentration of 1,25(OH)₂D₃-glycosides supplementation in reducing BCO by comparing the inclusions of 0 µg/kg, 0.5 µg/kg, 1.0 µg/kg, and 2.0 µg/kg of 1,25(OH)₂D₃-glycosides. The application of 1.0 µg/kg of 1,25(OH)₂D₃-glycosides reduced lameness by 53.7%, which reciprocally differed (P < 0.05) from 0 µg/kg and 0.5 µg/kg but was similar (P > 0.05) to 2.0 µg/kg. The second aim was to assess the timing for 1,25(OH)₂D₃-glycosides feeding by comparing the applications of 1.0 µg/kg of 1,25(OH)₂D₃-glycosides for the entire 56 d, the first 28 d, and the last 28 d. Feeding the broilers with 1.0 µg/kg of 1,25(OH)₂D₃-glycosides for the first 28 d alleviated BCO incidence by 53%, which significantly differed (P < 0.05) from the application for the last 28 d but was without significant difference (P > 0.05) from the supplementation for the entire 56 d. Therefore, feeding 1.0 µg/kg 1,25(OH)₂D₃-glycosides in the first 28 d is the optimum 1,25(OH)₂D₃-glycosides administration and provides equal protection to the supplementation for the entire production cycle. This early feeding strategy would minimize feed additive costs without compromising bone health while promoting protection against BCO lameness.