| 1. |
- Dahlin, Iris, et al.
(författare)
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Pest suppression in cultivar mixtures is influenced by neighbor-specific plant-plant communication
- 2018
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Ingår i: Ecological Applications. - : Wiley. - 1051-0761 .- 1939-5582. ; 28, s. 2187-2196
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Tidskriftsartikel (refereegranskat)abstract
- Increased plant genotypic diversity in crop fields can promote ecosystem services including pest control, but understanding of mechanisms behind herbivore population responses to cultivar mixtures is limited. We studied aphid settling on barley plants exposed to volatiles from different cultivars, aphid population development in monocultures and two-cultivar mixtures, and differences in volatile composition between studied cultivars. Aphid responses to one cultivar in a mixture were neighbor-specific and this was more important for pest suppression than the overall mixture effect, aphid colonization patterns, or natural enemy abundance. Aphid populations decreased most in a mixture where both cultivars showed a reduced aphid-plant acceptance after reciprocal volatile exposure in the laboratory, and reduced population growth compared to monocultures in the field. Our findings suggest that herbivore population responses to crop genotypic diversity can depend on plant-plant volatile interactions, which can lead to changes in herbivore response to individual cultivars in a mixture, resulting in slower population growth. The impact of plant-plant interaction through volatiles on associated herbivore species is rarely considered, but improved understanding of these mechanisms would advance our understanding of the ecological consequences of biodiversity and guide development of sustainable agricultural practices. Combining cultivars in mixtures based on how they interact with each other is a promising strategy for sustainable pest management.
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| 2. |
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| 3. |
- Hiron, Matthew, et al.
(författare)
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Crop damage by granivorous birds despite protection efforts by human bird scarers in a sorghum field in western Kenya
- 2014
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Ingår i: Ostrich: Journal of African Ornithology. - : National Inquiry Services Center (NISC). - 0030-6525. ; 85, s. 153-159
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Tidskriftsartikel (refereegranskat)abstract
- Cereal crop damage from granivorous birds poses a serious food security problem for subsistence farmers in sub-Saharan Africa. In this region, farmers may rely on human 'bird scarers' to limit crop damage. Here we report feeding behaviour and crop damage patterns caused by Village Weavers Ploceus cucullatus and African Mourning Doves Streptopelia decipiens during four days in a 0.12 ha sorghum field protected by two full-time bird scarers in western Kenya. Despite the scarers' efforts, almost 60% of the seed was lost before harvest. Bird abundance was largely determined by the presence of the bird scarers, with seed loss patterns being a function of distance from these people. Throughout the day, an average of 18 weavers (maximum 120) was present on the crop in any five-minute period. The number of mud projectiles thrown at the birds per 15 min showed only minor diurnal fluctuations, further suggesting that seed eaters attacked the crop throughout the day. Village Weaver individuals took an average 16 seeds per visit, whereas dove individuals took 32 seeds (maximum 105 and 455, respectively). Our study illustrates that avian crop pests can be extremely persistent and, even with consistent diurnal bird scaring activity, severely damage a small crop field. Bird scarers need to be active throughout daylight hours and patrol both the centres and edges of fields to create maximum disturbance to foraging seed eating birds. Further research is needed in order to investigate effects of local-and landscape-level land use patterns on the feeding behaviour of crop pests and the effectiveness of crop protection measures.
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| 4. |
- Josefsson, Jonas, et al.
(författare)
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Improving scientific rigour in conservation evaluations and a plea deal for transparency on potential biases
- 2020
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Ingår i: Conservation Letters. - : Wiley. - 1755-263X. ; 13:5
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Forskningsöversikt (refereegranskat)abstract
- The delivery of rigorous and unbiased evidence on the effects of interventions lay at the heart of the scientific method. Here we examine scientific papers evaluating agri-environment schemes, the principal instrument to mitigate farmland biodiversity declines worldwide. Despite previous warnings about rudimentary study designs in this field, we found that the majority of studies published between 2008 and 2017 still lack robust study designs to strictly evaluate intervention effects. Potential sources of bias that arise from the correlative nature are rarely mentioned, and results are still promoted by using a causal language. This lack of robust study designs likely results from poor integration of research and policy, while the erroneous use of causal language and an unwillingness to discuss bias may stem from publication pressures. We conclude that scientific reporting and discussion of study limitations in intervention research must improve and propose some practices toward this goal.
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| 5. |
- Kheam, Sokha, et al.
(författare)
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The effects of cultivar mixtures on insect pest and natural enemy abundance, diseases, and yield in tropical soybean cropping system
- 2024
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Ingår i: Biological Control. - 1049-9644 .- 1090-2112. ; 196
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Tidskriftsartikel (refereegranskat)abstract
- Increasing genotypic crop diversity via cultivar mixtures is a promising sustainable approach to control insect pests and diseases, thereby improving yield. The effects of genotypic diversity have not been studied for many crops. We investigated the effects of cultivar mixtures in a tropical soybean ( Glycine max L . Merrill) cropping system on i) insect pest abundance, ii) natural enemy abundance, iii) diseases, and iv) yield. In the field trial, three soybean cultivars were used, two commercial and one traditional, with a randomized complete block design. Significant differences among cultivars and some mixtures were found for certain insect pest abundance (whitefly and brown bean bug), but no consistent mixture effects were observed. Significant increases in natural enemies (predatory ant, lady beetle, parasitoid wasp, and dragonfly) were detected in some cultivar mixtures, compared to single cultivars. Higher genetic diversity in cultivar mixtures increased the abundance of certain natural enemies at specific plant stages. The cultivar mixtures did not alter disease symptoms or yield. These results were obtained during a season with very low overall pest pressure, and the effects of cultivar mixtures might be altered at higher pest pressure, which should be further investigated. This study highlights trade-offs in cultivar selection when jointly considering pest and disease abundance and yield, as no single cultivar (or mixture) performed better in all observed aspects. Our study supports the hypothesis that increasing cultivar mixtures can promote the abundance of certain natural enemies, suggesting the potential of cultivar mixture effects for biological control and sustainable agricultural management.
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| 6. |
- Kheam, Sokha, et al.
(författare)
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Volatile interactions between specific undamaged barley cultivars affect aphid feeding behavior and performance
- 2023
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Ingår i: Journal of Pest Science. - : Springer Science and Business Media LLC. - 1612-4758 .- 1612-4766. ; 96, s. 1049 - 1059
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have demonstrated that cultivar mixtures can reduce aphid plant acceptance and population development. It is still unknown as to which underlying mechanisms may contribute to this phenomenon. We investigated the effects of volatile interactions between undamaged barley cultivars on aphid feeding behavior and performance in the laboratory. Spring barley (Hordeum vulgare L.) cultivar Salome was exposed to volatiles from Fairytale (SeF), Anakin (SeA), or clean air (Se0). We used an electrical penetration graph to test the effect of exposure to neighbor volatiles on the feeding behavior and performance of bird cherry-oat aphids (Rhopalosiphum padi L.). We also assessed aphid relative growth rate, intrinsic rate of increase, and development time on exposed and unexposed Salome plants. Aphids spent significantly longer time on epidermis and mesophyll plant tissues on SeF than Se0, and no difference was observed between SeA and Se0. Significant decreases in the duration of phloem ingestion and phloem sustained ingestion were recorded in SeF showing that volatile-induced effects cause difficulty for aphids to feed. However, no differences in these variables were detected between SeA and Se0. We also observed reduced aphid relative growth rate and intrinsic rate of increase on SeF compared to Se0 and SeA. Our study demonstrated that, in a specific combination, exposure of one barley cultivar to volatiles from another one can change aphid feeding behavior and performance, probably due to changes in host plant properties/quality. Our results provide an insightful explanation of mechanisms responsible for the reduced aphid population development previously observed in the field.
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| 7. |
- Lisney, Thomas J., et al.
(författare)
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Behavioural assessment of flicker fusion frequency in chicken Gallus gallus domesticus
- 2011
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Ingår i: Vision Research. - : Elsevier BV. - 0042-6989 .- 1878-5646. ; 51:12, s. 1324-1332
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Tidskriftsartikel (refereegranskat)abstract
- To interact with its visual environment, an organism needs to perceive objects in both space and time. High temporal resolution is hence important to the fitness of diurnally active animals, not least highly active aerial species such as birds. However, temporal resolution, as assessed by flicker fusion frequency (FFF; the stimulus frequency at which a flickering light stimulus can no longer be resolved and appears continuous) or critical flicker fusion frequency (CFF; the highest flicker fusion frequency at any light intensity) has rarely been assessed in birds. In order to further our understanding of temporal resolution as a function of light intensity in birds we used behavioural experiments with domestic chickens (Gallus gallus domesticus) from an old game breed 'Gammalsvensk dvarghona' (which is morphologically and behaviourally similar to the wildtype ancestor, the red jungle fowl, G. gallus), to generate an 'Intensity/FFF curve' (I/FFF curve) across full spectrum light intensities ranging from 0.2 to 2812 cd m(-2). The I/FFF curve is double-branched, resembling that of other chordates with a duplex retina of both rods and cones. Assuming that the branches represent rod and cone mediated responses respectively, the break point between them places the transition between scotopic and photopic vision at between 0.8 and 1.9 cd m(-2). Average FFF ranged from 19.8 Hz at the lowest light intensity to a CFF 87.0 Hz at 1375 cd m(-2). FFF dropped slightly at the highest light intensity. There was some individual variation with certain birds displaying CFFs of 90-100 Hz. The FFF values demonstrated by this non-selected breed appear to be considerably higher than other behaviourally derived FFF values for similar stimuli reported for white and brown commercial laying hens, indicating that the domestication process might have influenced temporal resolution in chicken.
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| 8. |
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| 9. |
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| 10. |
- Rubene, Diana, et al.
(författare)
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Birds differentially prioritize visual and olfactory foraging cues depending on habitat of origin and sex
- 2023
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Ingår i: Royal Society Open Science. - : The Royal Society. - 2054-5703. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- Animals interpret their environment by combining information from multiple senses. The relative usefulness of different senses may vary between species, habitats and sexes; yet, how multimodal stimuli are integrated and prioritized is unknown for most taxa. We experimentally assessed foraging preferences of great tits (Parus major) to test whether urban and forest individuals prioritize visual and olfactory cues differently during foraging. We trained 13 wild-caught birds to associate multimodal (colour + odour) cues with a food reward and assessed their foraging preferences in a cue-separation test. In this, the birds could choose between the multimodal training cue and its olfactory or visual components. Our results suggest that the birds did not perceive multimodal cues in an integrated way, as their response was not stronger than for unimodal cue components. Urban birds preferred olfactory cues, while forest birds preferred visual cues. Nevertheless, female birds preferred the multimodal cue, while males foraged more randomly with respect to which cue was present. These findings contribute to our understanding of the relative roles of vision and olfaction in bird foraging behaviour. Future work should focus on how habitat-and sex-specific sensory prioritization modifies bird foraging behaviour and foraging success in the context of urban adaptations across populations.
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| 11. |
- Rubene, Diana, et al.
(författare)
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Disentangling olfactory and visual information used by field foraging birds
- 2019
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 9, s. 545-552
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Tidskriftsartikel (refereegranskat)abstract
- Foraging strategies of birds can influence trophic plant-insect networks with impacts on primary plant production. Recent experiments show that some forest insectivorous birds can use herbivore-induced plant volatiles (HIPVs) to locate herbivore-infested trees, but it is unclear how birds combine or prioritize visual and olfactory information when making foraging decisions. Here, we investigated attraction of ground-foraging birds to HIPVs and visible prey in short vegetation on farmland in a series of foraging choice experiments. Birds showed an initial preference for HIPVs when visual information was the same for all choice options (i.e., one experimental setup had all options with visible prey, another setup with hidden prey). However, if the alternatives within an experimental setup included visible prey (without HIPV) in competition with HIPV-only, then birds preferred the visual option over HIPVs. Our results show that olfactory cues can play an important role in birds' foraging choices when visual information contains little variation; however, visual cues are preferred when variation is present. This suggests certain aspects of bird foraging decisions in agricultural habitats are mediated by olfactory interaction mechanisms between birds and plants. We also found that birds from variety of dietary food guilds were attracted to HIPVs; hence, the ability of birds to use plant cues is probably more general than previously thought, and may influence the biological pest control potential of birds on farmland.
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| 12. |
- Rubene, Diana, et al.
(författare)
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Diversity patterns of wild bees and wasps in managed boreal forests: Effects of spatial structure, local habitat and surrounding landscape
- 2015
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 184, s. 201-208
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Tidskriftsartikel (refereegranskat)abstract
- Understanding patterns of species diversity at different spatial scales is important for adapting management and conservation efforts. We have therefore studied wild bee and wasp (Hymenoptera: Aculeata) diversity structure in forest landscapes and evaluated the importance of conservation management at the local and landscape levels. Surveys were conducted at 32 clearcuts in eight landscapes in a managed boreal forest region. We assessed the influence of local habitat and landscape composition on species richness patterns and the effect of prescribed burning and landscape affinity on species composition for all bees and wasps as well as ecological and functional groups. The relative contribution of alpha and beta diversity on the regional level was assessed by diversity partitioning and the beta diversity between landscapes further partitioned into components of species turnover and nestedness. Bee and wasp species richness increased with high flower richness and clearcut size, and species composition differed between burned and unburned sites. Thus, flower-rich early-successional sites in boreal forest landscapes are important habitats for wild bees and wasps. To support this fauna, openness should be maintained for extended periods by delaying or avoiding tree plantation at flower-rich spots on clearcuts. Beta diversity between landscapes accounted for the greatest proportion of the total regional gamma diversity, and over 70% of this diversity was due to species turnover. This implies that in order to maintain regional diversity, conservation efforts should be spatially dispersed, i.e. applied to every landscape of a few hundred square kilometers and adapted to the local species assemblages. (C) 2015 Elsevier Ltd. All rights reserved.
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| 13. |
- Rubene, Diana, et al.
(författare)
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Effectiveness of local conservation management is affected by landscape properties: Species richness and composition of saproxylic beetles in boreal forest clearcuts
- 2017
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 399, s. 54-63
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Tidskriftsartikel (refereegranskat)abstract
- Landscape context is known to affect species diversity patterns and can even influence the effectiveness of local conservation management in agricultural landscapes. For other land uses, like forestry, landscape effects are poorly known. We aimed to determine whether landscape composition modifies the response of saproxylic beetle species to local habitat and conservation management, with focus on dead wood and prescribed fire, in managed boreal forest landscapes. We surveyed beetles on 32 clearcuts in central Sweden. We measured local (fire, dead wood, flower resources, patch size) and landscape factors (fire, dead wood within 1-2 km radius), and analysed interactions between these in mixed models. The response was species richness of beetles with different habitat specialization - conifer specialists, deciduous specialists, flower visitor and pyrophilous species, and abundance of a red-listed species, Tragosoma depsarium. Local and landscape factors, as well as interactions between them, affected species richness patterns. Prescribed fire and amount of dead wood, both on local and landscape scale, affected species richness and composition of several groups. There were interactions between local and landscape factors in five models out of six. Locally, we observed a positive response to flower richness for several groups, while the response to prescribed fire and dead wood amounts typically was affected by landscape factors. The results suggest that effectiveness of local conservation management is affected by landscape properties; the positive effects of local dead wood amounts and burning occurred on clearcuts in landscapes with large amounts of dead wood, but not in landscapes with small amounts of dead wood. (C) 2017 Elsevier B.V. All rights reserved.
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| 14. |
- Rubene, Diana, et al.
(författare)
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Estimating bee and wasp (Hymenoptera: Aculeata) diversity on clear-cuts in forest landscapes - an evaluation of sampling methods
- 2015
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Ingår i: Insect Conservation and Diversity. - : Wiley. - 1752-458X .- 1752-4598. ; 8, s. 261-271
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Tidskriftsartikel (refereegranskat)abstract
- To assess species diversity efficiently and adequately, it is important to understand how species diversity assessments are affected by sampling effort and methodology. We evaluated methods for sampling bees and wasps on clear-cuts in managed boreal forest landscapes to assess the effects of trap type, sampling effort and time within season on observed species diversity. We found that pan traps and window traps captured similar numbers of species, whereas a much lower number was captured by trap-nests. The efficiency of the trap types varied between species groups, with pollen-collecting bees being most effectively sampled by pan traps and dead wood-nesting bees and wasps by window traps. Species turnover over time was moderate, and consequently the sampling period could be reduced to 5-6weeks in boreal forests and similar habitat types without a major decrease in the number of species collected. We recommend using window traps for bees and wasps in forest habitats. Combining trap types is recommended if the aim is to collect broad species assemblages, while single types are most useful for the efficient collection of specific species groups.
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| 15. |
- Rubene, Diana, et al.
(författare)
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Great Tits Learn Odors and Colors Equally Well, and Show No Predisposition for Herbivore-Induced Plant Volatiles
- 2022
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Ability to efficiently localize productive foraging habitat is crucial for nesting success of insectivorous birds. Some bird species can use olfaction to identify caterpillar-infested trees by detection of herbivore induced plant volatiles (HIPVs), but these cues probably need to be learned. So far, we know very little about the process of olfactory learning in birds, whether insectivorous species have a predisposition for detecting and learning HIPVs, due to the high ecological significance of these odors, and how olfaction is integrated with vision in making foraging decisions. In a standardized setup, we tested whether 35 wild-caught great tits (Parus major) show any preference for widely abundant HIPVs compared to neutral (non-induced) plant odors, how fast they learn to associate olfactory, visual and multimodal foraging cues with food, and whether the olfactory preferences and learning speed were influenced by bird sex or habitat (urban or rural). We also tested how fast birds switch to a new cue of the same modality. Great tits showed no initial preference for HIPVs compared to neutral odors, and they learned all olfactory cues at a similar pace, except for methyl salicylate (MeSA), which they learned more slowly. We also found no differences in learning speeds between visual, olfactory and multimodal foraging cues, but birds learned the second cue they were offered faster than the first one. Bird sex or habitat had no effect on learning speed or olfactory preference, but urban birds tended to learn visual cues more slowly. We conclude that insectivorous birds utilize olfactory and visual cues with similar efficiency in foraging, and that they probably don‘t have any special predisposition toward the tested HIPVs. These results confirm that great tits are flexible foragers with good learning abilities.
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| 16. |
- Rubene, Diana, et al.
(författare)
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Importance of high quality early-successional habitats in managed forest landscapes to rare beetle species
- 2014
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Ingår i: Biodiversity and Conservation. - : Springer Science and Business Media LLC. - 0960-3115 .- 1572-9710. ; 23, s. 449 - 466
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Tidskriftsartikel (refereegranskat)abstract
- Species adapted to early-successional forest habitats are in managed landscapes largely confined to clearcuts. To improve habitat quality on clearcuts, green tree and dead wood retention is widely applied in forestry; however, its effects on rare early-successional species have rarely been shown. We repeatedly surveyed two red-listed beetle species (Upis ceramboides and Platysoma minus) on clearcuts in a managed boreal forest landscape. We found that U. ceramboides decreased its occupancy over time while P. minus increased, indicating that red-listed species vary in their ability to successfully utilise managed habitats. We found no effect of connectivity on probability of occurrence, colonisation or extinction per clearcut. Trees retained alive improved habitat quality of clearcuts, since both species were more frequent in dead wood of such trees, in comparison to logging residues. We suggest that retention can be improved by protecting and creating dead wood as intact trees during harvesting. Rare specialist species require habitat of high quality, and consequently it is impossible to meet the requirements of these species on every clearcut. To preserve all early-successional species at a regional scale, we recommend focusing retention of green trees and dead wood to one or a few trees species on each clearcut and in each landscape.
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| 17. |
- Rubene, Diana
(författare)
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Insect diversity on clearcuts in boreal forest landscapes
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Intensive management and loss of natural disturbance dynamics in boreal forests leads to habitat loss and degradation for forest dwelling species. As a consequence, many species have become threatened, especially those dependent on dead wood. Integration of conservation in forest management is therefore essential for protecting boreal forest species diversity. To optimise conservation efforts, we need to understand species habitat requirements and diversity patterns in managed forests. This thesis aims to increase our understanding of insect species diversity patterns on clearcuts in boreal forest landscapes. I have surveyed beetles, bees and wasps on clearcuts in two boreal forest regions in Sweden and assessed the importance of clearcut properties and composition of surrounding landscape for species occurrence and diversity. Locally, amount of dead wood was positively associated with high species richness and individual species occurrence of certain wood-dependent beetles. Bee and wasp species richness increased with high local flower richness and clearcut size. Landscape composition was at least as important as local habitat characteristics for shaping diversity patterns. Burned forest land in surrounding landscape increased wood-dependent beetle species richness, while burning of clearcuts had only a weak effect on beetles, bees and wasps. This is probably because burned forest land on landscape scale includes higher habitat diversity with larger dead wood amounts, compared to burned clearcuts. Bee and wasp species richness increased with amount of early-successional habitats in the landscape, indicating that most species are associated with open habitats. The bee and wasp fauna differed considerably between landscapes. Therefore, conservation efforts need to be dispersed throughout the region to preserve the entire fauna. To promote insect species diversity on clearcuts in managed boreal forests, larger amount and diversity of dead wood needs to be created. Species dependent on sun-exposed dead wood or flowering plant richness can be favoured by prolonged open-habitat stage on parts of clearcuts. Concentrating certain conservation efforts to some clearcuts in the landscape is probably necessary in order to create high-quality habitats.
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| 18. |
- Rubene, Diana, et al.
(författare)
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Red Junglefowl Chicks Seek Contact With Humans During Foraging Task
- 2021
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Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Contact seeking with humans is documented in some domestic animals, mainly dogs, which have advanced communication skills. Domestication as a companion animal is thought to underlie this ability. However, also domesticated horses and goats display similar human-directed behaviors. This suggests either a broader effect of domestication on contact-seeking behavior, or alternatively, that social interactions with humans can result in the development of human contact seeking. As part of another study, we observed contact-seeking behavior in juvenile red junglefowl (Gallus gallus) chicks exposed to behavioral training since hatching, during a foraging task, where chicks were singly required to collect food rewards in a familiar arena using odor cues. If chicks left the arena, we recorded if they approached and looked up at the experimenter, or if they approached other objects (including another human). Chicks approached the experimenter significantly more often than they approached other objects. This behavior was not linked to a fast performance in the test arena, which gave some birds more time to explore the surroundings, or to learning ability measured in a cognitive task. Yet, the preference for the experimenter was lower for chicks that were handled more prior to the experiment. Also, approach probability was positively correlated with escape attempts in a novel arena test. The observed variation in approach behavior suggests a link to aspects of personality, and exposure to human interactions and experimental procedures. Our observations suggest that, although neither domesticated nor selectively bred, red junglefowl that are socialized with humans can potentially develop behavior used to describe contact seeking. Together with evidence from cognitive and behavioral studies, our results suggest that social experiences, not only domestication, can affect human-animal interactions. We propose how interactions between behavior, cognition and handling could be studied further in controlled settings to validate the preliminary findings of our study and uncover the underlying mechanisms.
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| 19. |
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| 20. |
- Rubene, Diana, et al.
(författare)
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The presence of UV wavelengths improves the temporal resolution of the avian visual system
- 2010
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 213:19, s. 3357-3363
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Tidskriftsartikel (refereegranskat)abstract
- The ability to perceive rapid movement is an essential adaptation in birds, which are involved in rapid flight, pursuing prey and escaping predators. Nevertheless, the temporal resolution of the avian visual systems has been less well explored than spectral sensitivity. There are indications that birds are superior to humans in their ability to detect movement, as suggested by higher critical flicker frequencies (CFFs). It has also been implied, but not properly tested, that properties of CFF, as a function of light intensity, are affected by the spectral composition of light. This study measured CFF in the chicken, Gallus gallus L., using four different light stimuli - white, full-spectrum (white with addition of UV), yellow (590 nm) and UV (400 nm) - and four light intensity levels, adjusted to relative cone sensitivity. The results showed significantly higher CFF values for full-spectrum compared with white light, as well as a steeper rate of increase with intensity. The presence of UV wavelengths, previously demonstrated to affect mate choice and foraging, appears to be important also for detection of rapid movement. The yellow and UV light stimuli yielded rather similar CFFs, indicating no special role for the double cone in flicker detection.
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| 21. |
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| 22. |
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| 23. |
- Wichman, Anette, et al.
(författare)
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Influence of Different Light Spectrums on Behaviour and Welfare in Laying Hens
- 2021
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Ingår i: Animals. - : MDPI AG. - 2076-2615. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Simple SummaryThis study investigated how different types of lighting affect laying hen behaviour and welfare. Amount and quality of light are important for birds to perform their natural behaviours, e.g., find food and water, recognise conspecifics and safely navigate their environment. The lighting used in poultry production facilities differs considerably from light conditions in the natural environment in which domestic fowl have evolved, which might have negative consequences for their welfare. This study examined whether light closely resembling natural daylight and light found in forest understory in Southeast Asia (ancestral habitat of jungle fowl) affected the behaviour of laying hens. The results revealed that birds had a preference for natural lighting in some situations. It is likely that these effects were due to the presence of ultraviolet light, which is known to be important for visual performance in birds. However, the differences were rather small, indicating that sufficient light intensity and other quality factors in the housing environment are more important in maintaining high welfare than the specific spectral composition of the light. This new knowledge can be used to improve the housing environment of domestic fowl by supplying artificial spectrums replicating natural lighting.Artificial commercial lighting used in animal production facilities can have negative influences on visual abilities, behaviour and welfare of domestic fowl. This study examined the effects of natural-derived light spectrums on behaviour, production and welfare of laying hens reared from hatching into adulthood. Comparisons were made of frequency of a range of behaviours associated with activity, aggression and comfort in birds kept in control light (commercial standard), daylight (full spectrum, including ultraviolet (UV) wavelengths and forest light (forest understorey, including UV). In addition, bird preferences for different lights, feather damage and egg production were monitored. The results showed that the behavioural repertoire of birds changed with age, while the effects of light treatment were subtle. Some evidence was found that birds preferred either daylight or forest light to control light, suggesting that inclusion of UV contributed to the preference. Daylight and forest light were associated with more active behaviours, and daylight with better plumage and later start of lay. Thus natural-like light may have beneficial effects on domestic fowl, but the differences between broad-spectrum light sources are rather small.
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