Effects of Outdoor Stocking Density on Growth, Feather Damage and Behavior of Slow-Growing Free-Range Broilers

Access to pasture is a main benefit of free-range broiler housing systems, yet the level of outdoor stocking density on broiler animal welfare remains unsettled. The growth, feather damage, pasture ranging and behaviors were assessed for 150 mixed-sex, slow-growing Freedom Rangers from 5 to 11 weeks of age of with free access to either a high outdoor stocking density pasture (0.5 m2 per bird) or a low outdoor stocking density pasture (2.5 m2 per bird). The probability (mean, 95% CI) of tail feather damage was greater for the high-density (23.1%, 16.3 to 31.7%) compared to the low-density group (11.9%, 7.1 to 19.3%). The percent of observations resulting in sunbathing and aggressive attacks (i.e., pecking and fighting behaviors) were greater for the high-density (1.0%, 0.6 to 1.8% and 0.5%, 0.2 to 1.3%, respectively) compared to the low-density group (0.3%, 0.1 to 0.7% and 0.1%, 0.0 to 0.4%, respectively). Furthermore, an interaction between treatment and age indicated that birds in the high-density group displayed greater stretching (during weeks 7 to 10) and panting (during weeks 6 and 9). Results of this study suggest that additional outdoor pasture space may be positively associated with broiler welfare.

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Determination of static space requirements for finishing bulls based on image analysis

Animal Welfare ◽

10.7120/09627286.30.3.007 ◽

2021 ◽

Vol 30 (3) ◽

pp. 307-314

Author(s):

N Volkmann ◽

J Stracke ◽

SL Rauterberg ◽

B Spindler ◽

N Kemper

Keyword(s):

Animal Welfare ◽

Social Space ◽

Bos Taurus ◽

Stocking Density ◽

Standing Position ◽

Weight Class ◽

Housing Systems ◽

Space Requirements ◽

Static Space

In Europe, conventional housing systems for finishing bulls (Bos taurus) tend to consist of group pens with a high stocking density. Up until now there have been no regulations in place defining bulls' space requirements, even although insufficient space allowance is considered to impair animal welfare. Our study aimed to measure the surface area that finishing bulls occupy in standing and lying positions. We observed 46 bulls on a German fattening farm. The animals from one pen were assigned to one of three weight classes (W1: < 450 kg; W2: 450–649 kg; W3: ≥ 650 kg), and two pens of each weight class were examined. For image recordings, a camera trap was installed above the pens. To analyse the covered surface, the recorded images (n = 242) were edited. Furthermore, the observed lying postures were differentiated in terms of lying position and stretched-out legs. On average, the areas covered by the bulls increased with class of bodyweight. A finishing bull covered up to 1.21 m2 in a standing position and up to 1.57 m2 in a lying position, the most space being needed in an outstretched position. The calculated values provide information only about the surface a finishing bull covered in different positions in the pen. In practice, additional dynamic and social space must be taken into account for recommendations on space requirements, in order to ensure adequate inter-individual distances, social interaction and characteristic behaviours to improve animal welfare.

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Microbiological vulnerability of eggs and environmental conditions in conventional and free-range housing systems

Semina Ciências Agrárias ◽

10.5433/1679-0359.2018v39n1p133 ◽

2018 ◽

Vol 39 (1) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

Julia Arantes Galvão ◽

Alexander Welker Biondo ◽

Fábio Sossai Possebon ◽

Thiago Luis Belém Spina ◽

Letícia Borges Nunes Correia ◽

...

Keyword(s):

Food Safety ◽

Animal Welfare ◽

Environmental Conditions ◽

Water Samples ◽

Production Plant ◽

Conventional System ◽

Salmonella Spp ◽

Standard Methods ◽

Free Range ◽

Housing Systems

Although Brazil is currently the world’s eighth largest egg exporter, the shift of consumers towards free-range eggs may present new sanitary challenges. This study aims to evaluate the microbiological vulnerability of eggs and environmental conditions in a farm certified for both conventional and free-range systems using two standard methods (enterobacteria counting and Salmonella spp. survey). Two high-producing farms were selected for this study, one under both conventional and free-range systems at the same place as the test farm, and another under conventional system only as a control farm. Enterobacteriaceae counts were determined for eggshells; and detection of Salmonella spp. was conducted in eggs, nest box material, feeder, and sponge samples from water dispensers, feeders, production plant, besides water samples from nipple dispensers and artesian well. The average enterobacteria count (log CFUmL-1) was 0.09 for conventional and 1.73 for free-range systems (p < 0.001). While Salmonella spp. was not detected in the conventional system but was present in one feeder and three eggshells from the free-range system. Therefore, the conventional system demonstrated better hygiene-sanitary status than the free-range one. Moreover, controlling food safety should always be considered when improving animal welfare.

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Physical quality characteristics of breast and leg meat of slow- and fast-growing broilers raised in different housing systems

Archives Animal Breeding ◽

10.5194/aab-63-337-2020 ◽

2020 ◽

Vol 63 (2) ◽

pp. 337-344

Author(s):

Melahat Özbek ◽

Metin Petek ◽

Sena Ardıçlı

Keyword(s):

Shear Force ◽

Quality Characteristics ◽

Housing System ◽

Breast Meat ◽

Physical Quality ◽

Fast Growing ◽

Free Range ◽

Housing Systems ◽

Meat Colour ◽

Slow Growing

Abstract. This study was made to determine the effects of genotype and housing system on physical quality characteristics of breast and leg meat of broilers under experimental conditions. The 150 slow-growing and 150 fast-growing 1 d old chicks were divided into three sub-groups with indoor raised slatted plastic floor, indoor concrete floor with rice hull litter, and free-range housing systems (2 genotype groups × 3 housing systems). All birds were offered the same diet and were housed in similar conditions until they were 56 d old. At slaughter, 10 birds from each main group were selected randomly to determine the quality characteristics of the meat. In total, 60 breast meat pieces (pectoralis major muscle) and 60 legs of the chickens were used for meat quality analysis including pH, shear force, and colour characteristics such as lightness (L∗), redness (a∗), yellowness (b∗), saturation (C∗), and hue angle (h∗). The pH of breast meat was significantly affected by genotype and housing system (P<0.001 and P<0.001). There were significant genotype × housing system interactions for pH (P<0.015 and P<0.001) and shear force values (P<0.007 and P<0.012) of leg and breast meat. There were no significant effects of genotype and housing system on leg and breast meat colour properties except for effects of genotype on redness (a∗) of breast meat (p<0.005) and effects of housing on redness of leg meat colour (p<0.031). Slow-growing chickens and chickens housed in deep litter had a higher redness (darker) value of breast and leg meat colour compared to fast-growing birds and free range and slatted floor. In conclusion, it can be said that fast-growing broilers may be more appropriate for slatted plastic floor housing and slow-growing broilers may be more suitable for a free-range housing system, but further research on factors affecting meat quality would be very beneficial, especially in slow-growing broilers.

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Impact of Environmental Complexity and Stocking Density on Affective States of Rainbow Trout (Oncorhynchus Mykiss)

10.21203/rs.3.rs-387346/v1 ◽

2021 ◽

Author(s):

M.G. Anderson ◽

A.M. Campbell ◽

D.D. Kuhn ◽

S.A. Smith ◽

L. Jacobs

Keyword(s):

Rainbow Trout ◽

Stocking Density ◽

High Density ◽

Low Density ◽

Affective States ◽

Environmental Complexity ◽

Rainbow Trout Oncorhynchus Mykiss ◽

Recirculating Aquaculture Systems ◽

Judgement Bias ◽

Ambiguous Situations

Abstract Affective states of animals can be assessed through judgement bias tests, evaluating responses to ambiguous situations. In this study, rainbow trout (n = 108) were housed in recirculating aquaculture systems under commercial conditions while trained at tank-level to discriminate between a positively reinforced chamber (feed) in one location and a negative chamber (positive punishment; chase by net for 1s) in the opposing location. Fish from successful tanks (2 out of 5 tanks) were then housed in treatment tanks of either high or low environmental complexity at either high (165 fish/m3) or low (69 fish/m3) stocking density. Trained fish were tested for latencies to approach three intermediate, ambiguous chambers. Fish housed in high-density tanks were faster to enter all chambers than those housed in low-density tanks (8.5s vs. 15.2s; P = 0.001), with faster entries into the positive (7.4s vs. 15.2s; P = 0.02) and near-negative chambers (10.2s vs. 17.4s; P = 0.006), suggesting that these fish were more optimistic to receive a feed reward. Tank complexity did not affect test outcomes. No differences between treatments were observed between body weight, length, and plasma cortisol. Overall, rainbow trout are capable of discriminating between cues during a judgement bias test and fish housed in high-density environments respond more optimistically in ambiguous situations compared to fish in low-density environments.

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Effect of Environmental Complexity and Stocking Density on Fear and Anxiety in Broiler Chickens

Animals ◽

10.3390/ani11082383 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2383

Author(s):

Mallory G. Anderson ◽

Andrew M. Campbell ◽

Andrew Crump ◽

Gareth Arnott ◽

Ruth C. Newberry ◽

...

Keyword(s):

Broiler Chickens ◽

Tonic Immobility ◽

Stocking Density ◽

Attention Bias ◽

High Density ◽

Low Density ◽

Affective States ◽

Complex Environment ◽

High Complexity ◽

Environmental Complexity

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers’ attention bias (measure of anxiety) and tonic immobility (measure of fear). In Experiment 1, individual birds were tested for attention bias (n = 60) and in Experiment 2, groups of three birds were tested (n = 144). Tonic immobility testing was performed on days 12 and 26 (n = 36) in Experiment 1, and on day 19 (n = 72) in Experiment 2. In Experiment 1, no differences were observed in the attention bias test. In Experiment 2, birds from high-complexity pens began feeding faster and more birds resumed feeding than from low-complexity pens following playback of an alarm call, suggesting that birds housed in the complex environment were less anxious. Furthermore, birds housed in high-density or high-complexity pens had shorter tonic immobility durations on day 12 compared to day 26 in Experiment 1. In Experiment 2, birds from high-density pens had shorter tonic immobility durations than birds housed in low-density pens, which is contrary to expectations. Our results suggest that birds at 3 weeks of age were less fearful under high stocking density conditions than low density conditions. In addition, results indicated that the complex environment improved welfare of broilers through reduced anxiety.

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Quantitative defect studies in semiconductor TEM samples prepared by low angle ion milling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138932 ◽

1995 ◽

Vol 53 ◽

pp. 512-513

Author(s):

L. Mulestagno ◽

J.C. Holzer ◽

P. Fraundorf

Keyword(s):

Sample Preparation ◽

Milling Time ◽

High Density ◽

Low Density ◽

Ion Milling ◽

High Quality ◽

Variable Angle ◽

Major Disadvantage ◽

Induced Defects

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).

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Scanning Electron Microscopic and Electrophoretic Observations on Barium Sulphate Used to Adsorb Clotting Factors

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647879 ◽

1975 ◽

Vol 33 (02) ◽

pp. 256-270

Author(s):

R. M Howell ◽

S. L. M Deacon

Keyword(s):

Electron Microscopy ◽

Factor Xa ◽

Barium Sulphate ◽

High Density ◽

Low Density ◽

Factor X ◽

Clotting Factors ◽

Electron Microscopic ◽

Complementary Techniques ◽

Scanning Electron

SummaryElectron microscopy and particle electrophoresis were found to be complementary techniques with which to complete the physical data from an earlier study on barium sulphates used to adsorb clotting factors from serum. The differences revealed by scanning electron microscopy (S. E. M.) in the physical shape of low and high density grades of barium sulphate particles appear to be of greater significance than charge as expressed by electrophoretic mobility, in determining whether or not precursor or preformed factor Xa is eluted.This conclusion was based on the finding that at pH values close to 7, where the adsorption from serum occurs, all samples with the exception of natural barytes were uncharged. However as the high-density, or soil-grade, was found by S. E. M. to consist of large solid crystals it was suggested that this shape might induce activation of factor X as a result of partial denaturation and consequent unfolding of the adsorbed protein. In contrast, uptake of protein into the centre of the porous aggregates revealed by S. E. M. pictures of low-density or X-ray grade barium sulphate may afford protection against denaturation and exposure of the enzyme site.The porous nature of particles of low-density barium sulphate compared with the solid crystalline forms of other grades accounts not only for its lower bulk density but also for its greater surface/gram ratio which is reflected by an ability to adsorb more protein from serum.Neither technique produced evidence from any of the samples to indicate the presence of stabilising agents sometimes used to coat particles in barium meals.

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