Perches and elevated platforms in commercial broiler farms: use and effect on walking ability, incidence of tibial dyschondroplasia and bone mineral content

Abstract

Modern fast-growing broilers spend excessive periods resting and their activity further decreases with age. Inactivity has been suggested to increase impaired gait and the incidence of leg disorders. Tibial dyschondroplasia (TD) is a common leg pathology in broilers. A more complex environment might facilitate more activity and improve leg health. Perches or elevated platforms bring variety to broilers' environment and could motivate more locomotion. This study examined the impact of perches and elevated platforms on walking ability, the occurrence of TD and level of bone ash and mineral contents. The investigation was performed on four commercial broiler farms throughout six consecutive batches with platforms and four to five with perches. On each farm at least two separate houses were included, enabling the comparison of furnished flocks to control flocks during each batch. Plastic slats with ramp access elevated by 30 cm or wooden perches of 10 and 30 cm height were offered in the furnished house. Farmers recorded the platform and perch usage twice a week with a five-point scale. Gait was scored before slaughter on a six-point scale according to the Welfare Quality® assessment protocol for poultry. The severity of TD was determined using a four-point scale on farm from all birds gait scored as 3 and at slaughter from 200 birds/flock. Farmers estimated 50% to 100% of the platforms to be occupied in all flocks throughout the entire growing period. Only single birds were perching, thus perch structures were constantly evaluated to be empty. Due to the low use, the perch-equipped houses were excluded when analysing bone content, walking ability and TD. On average, 30% of the tested birds exhibited gait score ⩾3. Younger scoring age resulted in a lower mean gait score and a lower percentage of scores 3 and 4 to 5. Overall, 2.3% of the birds examined at slaughter and 3.5% of the birds with gait score 3 were affected by TD. Leg health was better in birds with access to platforms: mean gait score, the percentage of birds scoring 3, and TD percentage and severity were lower in birds in platform-equipped houses. Elevated structures such as platforms, offering additional possibilities for locomotion to broilers seem to improve their leg health.

Wooden breast myopathy links with poorer gait in broiler chickens

“…Earlier studies already indicated that walking ability degenerates as birds grow older (Weeks et al, 2000;Bailie et al, 2013;Kaukonen et al, 2017), in addition, their behavioural activity dwindles and the latency to lie gets shorter (Norring et al, 2016;Bailie et al, 2013). This study further confirmed these findings of progressive immobility when birds became older as they were lying for longer episodes and had fewer bouts of walking.…”

Long-term access to live black soldier fly larvae (Hermetia illucens) stimulates activity and reduces fearfulness of broilers, without affecting health

“…The prevalence of tibial dyschondroplasia (TD) and white striping was higher compared to other studies 31,55,56 . For TD, the results are in line with a previous study that found a numerically higher occurrence in birds housed at 10 birds/m 2 , a similar stocking density as in the current study, compared to densities of 15 or 20 birds/m 2 , though the cause for this was unclear 57 .…”

Effect of litter type and perches on footpad dermatitis and hock burn in broilers housed at different stocking densities

“…Broilers are motivated to perch, but use perches rarely after the age of four weeks (Pettit-Riley & Estevez, 2001;Ventura et al, 2012). Their increased breast muscles have shifted the centre of gravity forward, which makes jumping and balance on perches difficult (Kaukonen et al, 2017). In the present study, broilers in all study groups perched rarely from the third week onwards.…”

“…The results can serve as recommendations for production conditions, although additional studies are suggested to investigate the mutual effects of various types of litter (Avdalovic et al, 2017;Kheravii et al, 2017), stocking densities and environmental enrichment (platforms, ramps, and outdoor access (ICFAW, 2009;Zhao et al, 2014;Norring et al, 2016;Kaukonen et al, 2017) on the occurrence of contact dermatitis and other health, behavioural and production indicators in broilers.…”