Effects of Range Access on Behavioral-Based Welfare Indicators and Foot Health Condition of Slow- and Fast-Growing Broiler

An analysis of the welfare of fast-growing and slower-growing strains of broiler chicken

“…There were a few welfare indicators which did not show such clear differences between FG and SG strains or where FG birds fared better. Whereas FG birds were generally less active than SG birds, they continued to perform some highly-motivated activities such as comfort behaviour at similar levels to many SG-slowstrains (Bokkers and Koene, 2003;Wallenbeck et al, 2016;Abdourhamane and Petek, 2023) and SG-mid strains (Baxter et al, 2021). And while FG birds were less likely to perch (Abeyesinghe et al, 2021) or more specifically to sleep or rest on perches (Yngvesson et al, 2018), the amount of sleeping and resting when all resting locations were considered together did not differ between strains of different growth potential (Wallenbeck et al, 2016;Yngvesson et al, 2018).…”

“…Birds were therefore generally kept in small group pens, usually of around 20 to 50 individuals, but as low as 6 and as high as 225 (Supplementary Table 1). A handful of studies provided small outdoor runs adjacent to indoor pens for some or all of the experimental groups (Comert et al, 2016;Lichnikova et al, 2017;Petek, 2022, Abdourhamane andPetek, 2023). Three studies reviewed in this section were conducted on commercial farms (enriched indoor with natural light, Baxter et al, 2021;or organic, Castellini et al, 2016;Lindholm et al, 2017).…”

“…Some of the studies provided both FG and SG strains with an identical but relatively high energy diet (e.g. Bokkers and Koene, 2003;Cavusoglu and Petek, 2019;Steenfeldt et al, 2019;Baxter et al, 2021;Petek, 2022, Abdourhamane andPetek, 2023), likely containing nutrient levels beyond those needed by SG birds and not fully representing the commercial situation. A different strategy was to provide an intermediate diet (Malchow et al, 2019b, Malchow et al, 2019c or non-identical diets, so that FG birds received higher energy/nutrient diets than SG birds for part or all of the growing period (Comert et al, 2016;Akyuz et al, 2022) (Supplementary Table 1).…”

“…Without feed restriction the welfare outcomes for FG birds tended to be worse than for SG-slow or SG-very slow birds in terms of health problems such as heart abnormalities, tendon degeneration, scoliosis and rotated tibia (Bokkers and Koene, 2003), reduced walking ability (Cavusoglu and Petek, 2019;Steenfeldt et al, 2019) or other aspects of leg health (Abdourhamane and Petek, 2022); contact dermatitis (Cavusoglu and Petek, 2019;Steenfeldt et al, 2019;Abdourhamane and Petek, 2022;Akyuz et al, 2022) and susceptibility to heat stress (Brugaletta et al, 2022). Plumage and skin were dirtier (Cavusoglu and Petek, 2019) and active behaviours such as locomotion and perching were reduced (Bokkers and Koene, 2003;Petek, 2022, Abdourhamane andPetek, 2023). The walking ability and feather cover of FG birds was also worse than that of an SG-mid strain when compared at 6 weeks of age, and active behaviours were reduced (Baxter et al, 2021).…”