Assessing the impact of Spirulina platensis and organic trace minerals on the incidence of bacterial chondronecrosis with osteomyelitis lameness in broilers using an aerosol transmission model

Spirulina platensis is an emerging poultry diet source due to its essential nutrition and bioactive ingredients. Spirulina microalgae confers beneficial effects on broiler's growth performance, immune response, and antioxidant activity. We investigated the effect of Spirulina platensis on BCO lameness, one of the most driving factors for economic and animal well-being concerns in the poultry industry. Additionally, supplementation of Availa ZMC containing organic trace minerals – zinc, manganese, and copper – was shown to alleviate lameness by 20 to 25%. We hypothesized that pairing microalgae and organic trace minerals might confer a synergistic effect in reducing BCO. A 2 × 2 factorial study, with microalgae (5% Spirulina platensis and 5% Spirulina platensis plus 0.15% Availa ZMC) and without microalgae (0.15% Availa ZMC and a negative control diet), plus one BCO source group were applied to 1,320 one-day-old chicks with 5 replicates of 60 chicks per treatment for lameness assessment. No significant difference in lameness was observed between the negative control and BCO source group (60.0% vs. 54.5%, P = 0.56). Compared to the negative control, Availa ZMC significantly reduced lameness by 51.2% (60.0% vs. 29.3%, P < 0.001), while microalgae slightly increased lameness by 6.3% (60.0% vs. 63.8%, P = 0.1). Availa ZMC plus microalgae alleviated lameness by 16.7% (50.0% vs. 60.0%, P = 0.005) compared to the negative control, which was statistically lower than microalgae alone and higher than Availa ZMC alone. These findings suggested the inclusion of 5% Spirulina platensis did not reduce BCO lameness, while Availa ZMC significantly alleviated lameness. When combined, there was no significant interaction between Availa ZMC and microalgae in mitigating broiler lameness.