Range use relationship with welfare and performances in four strains of organic broilers

International audience ; Alternative productions with outdoor access are acclaimed by consumers as animals can better express their natural behaviours. Eating grass and longer locomotion for example can impact animal use of outdoor range. To understand range use relationship with broiler’s welfare and performance, we studied four intermediate to slow-growing strains: JA757 (734 animals, rearing duration (RD): 71 days), S757N (735 animals, RD: 85 days), White Bresse (747 animals, RD: 106 days) and a dual-purpose crossbreed (771 animals, RD: 99 days). One hundred males of each strain were ranked according to their range use and divided in two extreme groups of 25 high- and low-rangers. We compared the means of our indicators regarding welfare (hock burns, pododermatitis, struggling on the slaughter line, tibial bone length and breaking-resistance) and performances (carcass weights and yields) by range use group. We did not observe any significant differences in welfare indicators collected at the slaughterhouse depending on range use in the four studied broiler strains. Only in the JA757, we found better leg health in high-rangers compared to low-rangers with 4% (p=0.006) shorter and 2% (p=0.021) stronger tibial bone which could be thanks to a higher locomotor activity in high-rangers compared to low-rangers. We reported significant reductions of carcass traits with range use in all the studied strains. We observed significantly lower carcass weights by 12% (p=0.006) in JA757 and by 7% (p=0.006) in White Bresse and significantly lower carcass yield by 2% (p=0.006) in S757N and by 1% (p=0.009) in the dual-purpose strains. These results could be due to higher locomotor activity of high-rangers compared to low-rangers. Therefore, later research could focus on how to maximize range use and its health benefices without compromising performances.The project PPILOW has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement N°816172.