Effects of dark brooders and overhangs on free-range use and behaviour of slow-growing broilers.

Broiler chickens often make limited use of the free-range area. Range use is influenced by type of shelter available. Range use may possibly be improved by a more gradual transition from the house to the range and by using dark brooders (secluded warm, dark areas in the home pen) that mimic aspects of a broody hen and possibly reduce fearfulness. The aim of this study was to assess effects of dark brooders on fearfulness, free-range use and behaviour later in life. Another aim was to test the chickens' preference for shelter type and the effects of overhangs outside of the pop holes to provide a gradual transition to the range. Three production rounds, each with 440 Sasso broiler chickens (110/group), were completed. Chicks were housed indoors from days 0 to 25; per round, two groups had access to a dark brooder, whereas the other two groups had conventional IR lamps. Fearfulness was assessed by the open field (OF) and tonic immobility (TI) tests on days 22 to 24 on 25 chicks/group per round. Birds were then moved to four mobile houses from which they could access both grassland with artificial shelter (AS) and short rotation coppice (SRC). Two of the houses had overhangs extending from the pop holes; these were switched between the four houses weekly. Free-range use and behaviour were observed three times daily from Monday to Friday. Dark brooders did not affect results from the OF or TI test, except for jumps in the OF test which tended to occur less often in brooded chicks. Neither dark brooders (34.9% without v. 31.7% with brooder) nor overhangs (32.5% without v. 34.1% with overhangs) influenced the percentage of chickens outside. Chickens showed a clear preference for SRC, range use increased over time in SRC, and more birds ranged farther from the house in SRC. Behaviours of chickens observed outside were mainly influenced by shelter type, age of the birds and distance from the house. Locomotion tended to occur more in the presence of overhangs. Overall, these results could not confirm the hypothesis that dark brooders would decrease fearfulness and thereby increase free-range use. Overhangs also did not improve free-range use, and neither brooders nor overhangs had considerable impact on behaviour of chickens outside. Chickens clearly preferred dense natural vegetation over AS and ranged farther in it, indicating that this type of shelter is more suitable for slow-growing free-range broilers.

Potential of chopped heath biomass and spent growth media to replace wood chips as bulking agent for composting high N-containing residues.

We investigated the potential of C-rich byproducts to replace wood chips as bulking agent (BA) during composting. The impact of these alternatives on the composting process and on compost stability and characteristics was assessed. Three BA (chopped heath biomass and spent growth media used in strawberry and tomato cultivation) were used for processing leek residues in windrow composting. All BA resulted in stable composts with an organic matter (OM) content suitable for use as soil amendment. Using chopped heath biomass led to high pile temperatures and OM degradation and a nutrient-poor compost with high C/P ratio appropriate for increasing soil organic carbon content in P-rich soils. Spent substrates can replace wood chips, however, due to their dense structure and lower biodegradation potential, adding a more coarse BA is required. Generally, the nutrient content of the composts with growth media was higher than the composts with wood chips and chopped heath biomass.

Effects of shelter type, early environmental enrichment and weather conditions on free-range behaviour of slow-growing broiler chickens.

Free-range use by broiler chickens is often limited, whereas better use of the free-range area could benefit animal welfare. Use of free-range areas could be stimulated by more appropriate shelter or environmental enrichment (by decreasing birds' fearfulness). This study aimed to assess the effects of shelter type, early environmental enrichment and weather conditions on free-range use. Three production rounds with 440 slow-growing broiler chickens (Sasso T451) were carried out. Birds were housed indoors in four groups (two with males, two with females) from days 0 to 25, during which two of the groups received environmental enrichment. At day 23 birds' fearfulness was assessed with a tonic immobility (TI) test (n=100). At day 25 all birds were moved (in mixed-sex groups) to mobile houses, and provided with free-range access from day 28 onwards. Each group could access a range consisting for 50% of grassland with 21 artificial shelters (ASs, wooden A-frames) and for 50% of short rotation coppice (SRC) with willow (dense vegetation). Free-range use was recorded by live observations at 0900, 1300 and 1700 h for 15 to 21 days between days 28 and 63. For each bird observed outside the shelter type (AS or SRC), distance from the house (0 to 2, 2 to 5, >5 m) and its behaviour (only rounds 2 and 3) were recorded. Weather conditions were recorded by four weather stations. On average, 27.1% of the birds were observed outside at any given moment of observation. Early environmental enrichment did not decrease fearfulness as measured by the TI test. It only had a minor effect on the percentage of birds outside (0.4% more birds outside). At all distances from the house, SRC was preferred over AS. In AS, areas closer to the house were preferred over farther ones, in SRC this was less pronounced. Free-range use increased with age and temperature and decreased with wind speed. In AS, rainfall and decreasing solar radiation were related to finding more birds outside, whereas the opposite was true in SRC. Behaviour of the birds depended on shelter type, distance from the house, early environmental enrichment, time of day and age. Chickens ranged more and farther in SRC, possibly because this provided a greater sense of safety because of the amount of cover and/or better protection against adverse weather conditions. These results indicate that SRC with willow is a more appropriate shelter for slow-growing broiler chickens than A-frames.

Opportunities and barriers to on-farm composting and compost application: A case study from northwestern Europe.

Maintaining and increasing soil quality and fertility in a sustainable way is an important challenge for modern agriculture. The burgeoning bioeconomy is likely to put further pressure on soil resources unless they are managed carefully. Compost has the potential to be an effective soil improver because of its multiple beneficial effects on soil quality. Additionally, it fits within the bioeconomy vision because it can valorize biomass from prior biomass processing or valorize biomass unsuitable for other processes. However, compost is rarely used in intensive agriculture, especially in regions with high manure surpluses. The aim of this research is to identify the barriers to on-farm composting and the application of compost in agriculture, using a mixed method approach for the case of Flanders. The significance of the 28 identified barriers is analyzed and they are categorized as market and financial, policy and institutional, scientific and technological and informational and behavioral barriers. More specifically, the shortage of woody biomass, strict regulation, considerable financial and time investment, and lack of experience and knowledge are hindering on-farm composting. The complex regulation, manure surplus, variable availability and transport of compost, and variable compost quality and composition are barriers to apply compost. In conclusion, five recommendations are suggested that could alleviate certain hindering factors and thus increase attractiveness of compost use in agriculture.