Background and Objective: Commercial broilers are raised for quick growth and enhanced feed efficiency. However, weight gain does not correlate with slower development of the skeletal system. The weight load causes skeletal problems in birds, forcing them to spend most of their time lying down and unable to express normal behavior. The goal of this research was to evaluate the effect of free-range production system (FRPS) on broilers' bone strength. Materials and Methods: The birds were distributed in a completely randomized design with 4 treatments (A, B, C and D) and 3 replications. Three birds were selected randomly from each replication, weighed and then euthanized fortnightly. Increase in skeletal load was estimated for each bird, right tibia de-fleshed, weighed and severed at the midpoint of its length. The inner and outer tibia midway diameters were measured, diameter ratios were (inner to outer) computed and expressed as percentages (IO). Tibia ash (%) and IO ratio were used to determine bone strength. Results: FRPS increased bone ash (%) and decreased skeletal load. Tibia ash (%) of the control treatment (D) and treatments A and B were significantly different (p<0.05). There was a positive correlation between tibia ash (%) and the IO ratio (Spearman’s correlation of r = 0.56). Conclusion: The FRPS reduced the load on the bird’s skeleton proportionally to its development stage, suggesting that FRPS increased the strength of bones, thus improved bird welfare.
Peter Mbato, Wanzila Mutinda, Noah Maritim and Nicholas Odongo, 2023. Free-Range Production System can Improve Bone Strength in Broilers. International Journal of Poultry Science, 22: 119-125.