Use of the range area in organic egg production systems: effect of climatic factors, flock size, age and artificial cover

The effects of organic diets, with or without supplements of betaine, saponin, fructo-oligosaccharide and methionine, on the health, performance and gut flora of pullets were investigated. A comparison was also made between birds fed organic diets and those fed a non-organic diet. Day-old Lohmann Tradition pullets were reared in 24 groups of 64 chicks indoors until 11 weeks, and then in 48 groups of 24 to 27 chicks with access to range until 17 weeks of age. Groups of birds were fed one of eight diets, a conventional rearing diet with supplementary amino acids, an organic basal diet, organic basal plus methionine and organic basal supplemented with one of the test ingredients. At most stages of growth the birds fed the conventional diet and those fed the basal diet with methionine performed better than those that had no supplemental methionine. Other dietary treatments had no consistently significant effect on growth, the microbial populations within the gastro-intestinal tract of the birds or the number of parasite eggs excreted. After 5 weeks with access to range, the birds that were fed three out of five diets regarded as deficient in sulphur amino acids achieved similar weights (P . 0.05) to birds that received diets adequate in sulphur amino acids. Health and welfare of birds fed organic diets was not adversely affected; however, an investigation of birds housed in larger flocks and taken into the laying phase, when physical demands on birds are greatest, is required.

Section: Discussionsupporting

confidence: 88%

The effect of organic diets on the performance of pullets maintained under semi-organic conditions

Acamovic

Sandilands

Kyriazakis

et al. 2008

“…In addition to fearfulness, range use seems to be dependent on a number of other variables. These may include birds' previous experience with the environment and the outdoor range (Grigor et al, 1995;Janczak and Riber, 2015), pop-hole size, accessibility to the range (Gilani et al, 2014), and structures on the range (Hegelund et al, 2005;Rault et al, 2013). In the present experiment, the range areas were fenced off and had wire mesh across the top; hence the birds were protected from predators.…”

Section: Discussionmentioning

confidence: 98%

“…The majority of studies in this area report much lower range use. Hegelund et al (2005) studied flocks ranging from 513 to 6000 hens, and found that an average of 9% of hens used the range area, with large variations within and between flocks. Hegelund et al (2006) reported that an average of 18% of hens used the outdoor range area in flocks of 1200 to 5000 hens, and Dawkins et al (2003) found a maximum of <15% of the total flock accessing the range area during the day, using in situ behaviour observations of broiler chickens on commercial farms.…”

Section: Discussionmentioning

confidence: 99%

“…Range use is thought to be negatively correlated with rates of SFP (Lambton et al, 2010) and plumage damage (Green et al, 2000;Nicol et al, 2003;Mahboub et al, 2004). However, there are a number of factors that reportedly affect range use in laying hens, including weather, condition of the range area, pop-hole size (Hegelund et al, 2005;Gilani et al, 2014), flock size (Bestman and Wagenaar, 2003; GebhardtHenrich et al, 2014), and the presence of vertical structures (Rault et al, 2013), shade structures, and vegetation on the range (Bestman and Wagenaar, 2003;Zeltner and Hirt, 2003;Nicol et al, 2003). In particular, fearfulness may be a mitigating factor in range use, where fearful birds are thought to be less likely to access the outdoor range area (Grigor et al, 1995).…”

Section: Introductionmentioning

confidence: 99%

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Relationships between range access as monitored by radio frequency identification technology, fearfulness, and plumage damage in free-range laying hens

Hartcher

Hickey

Hemsworth

et al. 2016

Severe feather-pecking (SFP), a particularly injurious behaviour in laying hens (Gallus gallus domesticus), is thought to be negatively correlated with range use in free-range systems. In turn, range use is thought to be inversely associated with fearfulness, where fearful birds may be less likely to venture outside. However, very few experiments have investigated the proposed association between range use and fearfulness. This experiment investigated associations between range use (time spent outside), fearfulness, plumage damage, and BW. Two pens of 50 ISA Brown laying hens ( n = 100) were fitted with radio frequency identification (RFID) transponders (contained within silicone leg rings) at 26 weeks of age. Data were then collected over 13 days. A total of 95% of birds accessed the outdoor run more than once per day. Birds spent an average duration of 6.1 h outside each day over 11 visits per bird per day (51.5 min per visit). The top 15 and bottom 15 range users (n = 30), as determined by the total time spent on the range over 13 days, were selected for study. These birds were tonic immobility (TI) tested at the end of the trial and were feather-scored and weighed after TI testing. Birds with longer TI durations spent less time outside ( P = 0.01). Plumage damage was not associated with range use ( P = 0.68). The small group sizes used in this experiment may have been conducive to the high numbers of birds utilising the outdoor range area. The RFID technology collected a large amount of data on range access in the tagged birds, and provides a potential means for quantitatively assessing range access in laying hens. The present findings indicate a negative association between fearfulness and range use. However, the proposed negative association between plumage damage and range use was not supported. The relationships between range use, fearfulness, and SFP warrant further research.Keywords: radio frequency identification, range use, free-range, plumage damage, fearfulness Implications Free-range egg production has been increasing in recent years in a number of countries. However, little is known about ranging behaviour in laying hens. Severe feather-pecking (SFP), which may be associated with reduced range use, poses a significant risk to hen welfare and productivity in non-cage housing systems. This experiment successfully collected data on the range use of individual birds, via radio frequency identification technology, and fearfulness was negatively associated with range use. An improved understanding of range use and other behavioural correlates may allow enhanced management and housing, and enable the eventual control of SFP, a highly deleterious behaviour in the egg industry. IntroductionSevere feather-pecking (SFP) is a highly prevalent and extremely injurious behaviour in laying hens. It causes serious negative impacts in the egg industry, in terms of both animal welfare and production efficiency. SFP is multifactorial, with contributing factors including environmental, social, genetic, and nutritiona...

“…It was not, however, proportional to group size as a smaller proportion of birds were seen on the veranda in the larger groups. A decreasing percentage of birds go outside with increasing flock size (Hegelund et al, 2005), which has also been found in smaller flocks comprising 250, 500 and 1000 birds (Harlander-Matauschek, 2001). In terms of number of birds, however, both these studies showed more birds outside as flock size increased.…”

Section: Discussionmentioning

confidence: 83%

Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. I: egg laying, and use of veranda and outdoor area

Steenfeldt

Nielsen

2015

Multi-tier aviary systems are becoming more common in organic egg production. The area on the tiers can be included in the net area available to the hens (also referred to as usable area) when calculating maximum indoor stocking densities in organic systems within the EU. In this article, results on egg production, laying behaviour and use of veranda and outdoor area are reported for organic laying hens housed in a multi-tier system with permanent access to a veranda and kept at stocking densities (D) of 6, 9 and 12 hens/m 2 available floor area, with concomitant increases in the number of hens per trough, drinker, perch and nest space. In a fourth treatment, access to the top tier was blocked reducing vertical, trough and perch access at the lowest stocking density (treatment D6x). In all other aspects than stocking density, the experiment followed the EU regulations on the keeping of organic laying hens. Laying percentage was significantly lower ( P < 0.05) in D12 compared with the other stocking densities (90.6% v. 94.3% (±0.7)), most likely due to the concomitant reduction in nest space and drinker availability per hen. No systematic effects of density were found on other laying variables (egg weight, eggs laid outside nests, aviary side preferences). Number of hens using the veranda increased with stocking density. Hens primarily used the range near the house (within 50 m) and hens kept at the lowest stocking density and the smallest group size appeared to use the outdoor area more extensively, based on an assessment of vegetation cover ( P < 0.05). For the measures reported here, the welfare consequences of increased stocking density were assessed to be minor; additional results are reported in the associated article (Steenfeldt and Nielsen, 2015).