Effects of environmental enrichment on health and bone characteristics of fast growing broiler chickens

Abstract

Providing environmental enrichment for broilers is a potential strategy to increase welfare, activity, and health. The aim of this study was to evaluate the effect of environmental enrichment on health and leg bone characteristics of broilers. One control and 8 types of enrichment were included: 2 distances between food and water (7 and 3.5 m), roughage, vertical panels, straw bales, 2 platforms (30 and 5 cm), and a lowered stocking density (34 kg/m 2 ). Birds were kept according to conventional Danish guidelines. The study included 58 pens with approximately 500 birds each. On day 35 of age, 25 birds per pen were killed and included in a postmortem analysis of wooden breast, body condition scores, pathological conditions (femoral head necrosis, arthritis, tenosynovitis, fractures, tibial dyschondroplasia, and twisted tibiotarsus), muscle width of the lower leg, and tibiotarsus properties (bone strength, weight, length, and proximal diameter, middle diameter, and distal diameter). It was predicted that environmental enrichment would have a positive effect on pathology with the exceptions that environmental enrichment that increased activity would pose a risk factor for wooden breast development, and straw bales would be a risk factor for bacterial infections (arthritis, tenosynovitis, and femoral head necrosis). Furthermore, it was hypothesized that enriched groups would have increased muscle width, bone strength, and dimensions of the tibiotarsus. Broilers with 7 m between food and water had a longer distal diameter of the tibiotarsus than those with straw bales ( P = 0.04). The birds provided with vertical panels had wider leg muscle than the treatments with roughage ( P = 0.045), 3.5 m distance ( P = 0.049), and straw bales ( P = 0.044). No effects were found for the remaining outcomes. These results suggest that provision of vertical panels and increased distance between resources can result in larger muscle and bone dimension, possibly having a positive effect on leg health. Furthermore, the provision of environmental enrichment does not appear to be a risk factor for wooden breast or bacterial infection.

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 .…”

The Productivity and Financial Impacts of Eight Types of Environmental Enrichment for Broiler Chickens

“…This study, therefore, sets out to address this limitation by exploring the financial implications of eight types of environmental enrichment ( Table 1). The data used in this analysis was derived from a larger study reported in several earlier studies [12][13][14][15]. These previously published studies investigated the effect of the same eight types of environmental enrichment on a range of health and welfare measures, fearfulness, learning ability and activity levels.…”

Effects of pen enrichment on leg health of fast and slower-growing broiler chickens

“…The lack of activity, together with a fast growth rate, may impair bone development, which can result in suboptimal leg health or even lameness [12,18,25,26,27]. It has been shown that a lower stocking density [21,28,29,30,31], placing platforms and/or ramps [21,23,32,33], perches [31,32], large distance between feed and water [18,33,34], different dustbathing materials, such as moss-peat [35], and worms or insects in a dustbathing area [36,37] resulted in lower prevalence of leg disorders and lower mortality rate, although we did not find this in an earlier comparable study [38]. Increasing physical activity and locomotion may thus result in lower incidence of leg problems by stimulating tibia morphological, biophysical and mechanical properties [18,33,39,40,41].…”