Aviary Research Articles

Comparison of egg production, quality and composition in three production systems for laying hens

The increasing public concern for animal welfare has pushed the poultry sector to progressively replace conventional battery cages (CC) for laying hens with alternative systems such as enriched cages (EC) and aviaries (AV). The aim of this study was to compare laying performance, egg location, and egg quality associated with these three housing types. The experiment was conducted in twelve pilot-scale chambers fitted out with one of the three treatments. Each chamber housed 30 Lohmann LSL-Lite laying hens from 23 to 32 weeks of age. The available area was 492, 780, and 1120 cm²/hen for CC, EC, and AV, respectively. The EC and AV chambers were equipped with nest boxes, perches, and a pecking/scratching area (PSA). In the AV chambers, hens had free access to a space arranged in three levels with a wood shaving litter on the ground level as a PSA. Hen-day production was recorded and egg quality assessment included egg cleanliness, weight and proportion of each component (albumen, yolk, and shell) but also pH, Haugh unit, and meat spots for albumen; color intensity and blood spots for yolk; thickness and resistance for shell. The laying rate and egg weight were similar for CC and EC (around 96.5% and 59.5 g; P > 0.05). For AV, these parameters were significantly lower (77.2% and 58.6 g; P < 0.001) but the differences compared to the cage systems progressively reduced across time. Nearby 70% of the eggs were laid in the nests with EC while almost all of the eggs were laid on the litter at ground level with AV. The rate of clean eggs was around 77% for both cage systems compared to 14% for AV. Most of egg quality traits were identical for the three systems (P > 0.05) but there was a lower yolk proportion for eggs laid in AV (25.2% versus 25.7% for cages systems; P < 0.001) and higher shell resistance for eggs laid in CC (40.7 N versus 39.3 N for alternative systems; P < 0.001). Lower laying performance observed with AV could be explained by higher animal activity and competition for facilities, but these factors were not measured in this study. The reduction of the difference in egg productivity over time compared to cage systems suggest the need for a period of training/adaptation for pullets/hens kept in such an environment. An enriched cage system seems a balanced solution that combines both laying productivity and improved animal welfare. Further research should be performed to improve acceptance and appropriate use of resources by birds in an aviary system.

Sistem Pendukung Keputusan Menentukan Lokasi Rumah Burung Walet (RBW) Menggunakan Metode AHP dan SAW

Swallow's nests are sold as ingredients for soups and raw materials for medicines. Because the price of swiftlet nests is very expensive so many people have started to build a swallow bird house (RBW) by spending a considerable amount of money for swallow bird cultivation. But to build RBW and grow swallow birds requires an exact and optimal location. This study aims to create a system for determining the location of a computerized swallow house construction by implementing the Analytic Hierarchy Process (AHP) method and the Simple Additive Weighting (SAW) method in determining the exact location of swallow bird house construction to reduce the level of loss and error in site selection. The AHP method is used in estimating the value of each parameter that is determined while the SAW method is used in assessing levels. Based on the 6 criteria for swallow bird locations, namely location height, distance from the city center (industry), air temperature, distance from rice fields / plantations, distance from waterways, and distance from other buildings, the decision support system built can be a choice of solutions to facilitate farmers and swallow nest entrepreneurs in determining the exact and optimal location of swallow bird houses.

An investigation of cross-reactivity between the poultry red mite and house dust and storage mites in dogs with contact with chickens infested with red mites.

The European poultry red mite (PRM) Dermanyssus gallinae, a common ectoparasite of laying chickens and pigeons; it also can feed on other birds, humans and domestic animals, causing clinical signs ranging from mild discomfort to severe dermatitis. Little is known about possible hypersensitivity to PRM or cross-sensitization with house dust or storage mites. Knowledge on possible PRM immunoglobulin E (IgE)-mediated allergy and possible cross-sensitization with house dust and storage mites may facilitate the clinical approach. The aim herein was to clarify possible evidence of type I hypersensitivity to PRM in dogs and possible occurrence of cross-sensitization with house dust and storage mites. Sixteen dogs with chronic contact with PRM-infested chickens from traditional bird houses and 10 control dogs with no contact with birds. Dogs were subjected to intradermal testing (IDT) and serum specific IgE (sIgE) determination for house dust and storage mites and D.gallinae. The highest wheal score was obtained with 0.1mg/mL D. gallinae extract. Positive IDT reactions to PRM were found in four of 10 control dogs and in 10 of 16 from the chicken-exposed group. SIgE to PRM was detected in one control and in seven dogs exposed to chickens. No significant correlation was found between IDT or sIgE scores to PRM and house dust and storage mites. Contact with PRM-infested chickens may lead to sensitization without allergy, independently from sensitization to house dust and storage mites.

Talud Stabilization of Bird House Residential in Manaus City

Slope stabilization techniques have been increasingly used in the field, mainly due to high market values for land in large urban centers. With this, the technical feasibility study guarantees the application of the best solution for each case. From this context, we sought to verify the best method of containment by means of a case study according to the parameters of soil resistance, cohesion and angle of friction at the residence Morada dos Pássaros in Manaus - AM. The methodology used was of an exploratory nature with a case study, where in the first phase the topographic survey of the study area was carried out. In the second phase, it was sought to plan the location of the holes, according to ABNT NBR 8036 (1983). for the accomplishment and technical follow-up of the investigation of the soil in the place by means of the test of percussion to the percussion - SPT and in the 3º phase was characterized by means of physical and mechanical laboratory test with the collection of material. Considering the collected data, it is noticed that the soil is with 3% of plasticity, concluding that a soil with plasticity below 7% loses the capacity to be molded and to become brittle. Therefore, it is concluded that the best technique to be used is geosynthetics, both in cost and in soil absorption, due to the feasibility of redistribution of stresses and slope deformations.

Floral Traits Predict Frequency of Defecation on Flowers by Foraging Bumble Bees.

Flowers may become inoculated with pathogens that can infect bees and other critical pollinators, but the mechanisms of inoculation remain unclear. During foraging, bees may regurgitate or defecate directly onto flower parts, which could inoculate flowers with pollinator pathogens and lead to subsequent disease transmission to floral visitors. We tested if captive eastern bumble bees (Bombus impatiens) (Cresson) (Hymenoptera: Apidae) defecate on floral surfaces during foraging and if flower shape played a role in the probability of defecation and the quantity of feces deposited on floral surfaces. Captive Bombus impatiens were fed a solution of fluorescent dye and sucrose, then allowed to forage freely on flowers of a variety of shapes in a flight cage. Flowers were then examined under ultraviolet light for fluorescing fecal matter. We found that bumble bees did defecate on floral surfaces during foraging and that composite flowers with a large area of disk flowers were the most likely to have feces on them. Our results point to defecation by bumble bees during foraging as a potential mechanism for inoculation of flowers with pollinator pathogens and suggest that flower shape could play a significant role in inoculation.

Flights of a Multirotor UAS with Structural Faults: Failures on Composite Propeller(s)

Data acquired from several flights of a custom-fabricated Hexacopter Unmanned Aerial System (UAS) with composite structure (carbon fiber arms and central hub) and composite (carbon fiber) propellers are described in this article. The Hexacopter was assembled from a commercially available kit (Tarot 690) and flown in manual and autonomous modes. Takeoffs and landings were under manual control and the bulk of the flight tests was conducted with the Hexacopter in a “position hold” mode. All flights were flown within the UAS flight cage at Parks College of Engineering, Aviation and Technology at Saint Louis University for approximately 5 min each. Several failure conditions (different types, artificially induced) on the composite (carbon fiber) propellers were tested, including failures on up to two propellers. The dataset described in this article contains flight data from the onboard flight controller (Pixhawk) as well as three accelerometers, each with three axes, mounted on the arms of the Hexacopter UAS. The data are included as supplemental material.

Exposure to Non-Native Tropical Milkweed Promotes Reproductive Development in Migratory Monarch Butterflies.

Background: North American monarchs (Danaus plexippus) are well-known for their long-distance migrations; however, some monarchs within the migratory range have adopted a resident lifestyle and breed year-round at sites where tropical milkweed (Asclepias curassavica) is planted in the southern coastal United States. An important question is whether exposure to exotic milkweed alters monarch migratory physiology, particularly the ability to enter and remain in the hormonally-induced state of reproductive diapause, whereby adults delay reproductive maturity. Cued by cooler temperatures and shorter photoperiods, diapause is a component of the monarch’s migratory syndrome that includes directional flight behavior, lipid accumulation, and the exceptional longevity of the migratory generation. Methods: Here, we experimentally test how exposure to tropical milkweed during the larval and adult stages influences monarch reproductive status during fall migration. Caterpillars reared under fall-like conditions were fed tropical versus native milkweed diets, and wild adult migrants were placed in outdoor flight cages with tropical milkweed, native milkweed, or no milkweed. Results: We found that monarchs exposed to tropical milkweed as larvae were more likely to be reproductively active (exhibit mating behavior in males and develop mature eggs in females) compared to monarchs exposed to native milkweed. Among wild-caught fall migrants, females exposed to tropical milkweed showed greater egg development than females exposed to native or no milkweed, although a similar response was not observed for males. Conclusions: Our study provides evidence that exposure to tropical milkweed can increase monarch reproductive activity, which could promote continued residency at year-round breeding sites and decrease monarch migratory propensity.

Modification of perchery system: Preference for ramps rather than ladders during early adaptation period for cage-reared pullets

Poor early adaptation in aviaries has adverse effects on welfare and the later production. Effects of system modification by ramps and ladders on early adaptation of birds were investigated. A total of 240 pullets and 24 cockerels of Yukou Jing Pink II parent stock were allocated into six perchery compartments at the age of 83 days from conventional cages. Three compartments were modified with ramps of different angles, 30°, 40° and 30° & 50° combination. The other compartments were fitted with 2 ladders, with 22 cm steps and 33 cm steps. Spatial distribution of birds and eggs, as well as the data of ramps and ladders utilization were used to assess birds’ adaptation and the effectiveness of modification facilities. A higher proportion of hens got onto the tiered platforms in ramp group (p<0.001) and engaged in feeding (p=0.002). Inversely more than 85.0% of hens dwelled on the system floor in the ladder group for the whole observation period. The proportion of birds feeding increased over time (p<0.001), with the proportion of birds lying decreasing (p<0.001). A higher frequency of utilization of ramps was found compared with ladders (4.5-25.8 vs. 2.8-14.7 times/40 birds per hour). For ramp use, 79.3% of hens negotiated level change by using 30° ramp and behavioral process was also found related with the type of ramps. On the contrary, very few successful level changes were observed via ladders and 60% of ladder use was ended with birds backing to the system floor. Besides, a higher proportion of non-nest eggs was recorded in ladder group in the early laying period. These results indicated that modification of ramps is more applicable for improving birds’ early adaptation and later production in perchery system of multi-tier, especially for pullets reared in conventional cages. Keywords: animal welfare, modification, perchery system, adaptation, pullet, ramp, enriched cage system DOI: 10.25165/j.ijabe.20191204.4030 Citation: Zheng H Y, Li B M, Tong Q, Chen G, Li X Y. Modification of perchery system: Preference for ramps rather than ladders during early adaptation period for cage-reared pullets. Int J Agric & Biol Eng, 2019; 12(4): 34–42.

Bats Actively Use Leaves as Specular Reflectors to Detect Acoustically Camouflaged Prey

Filtering relevant signals from noisy sensory input is a crucial challenge for animals [1, 2]. Many bats are acoustic specialists relying on sound to find prey. They discern salient acoustic signals from irrelevant background masking noise. It has long been considered a sensory impossibility for bats to use solely echolocation for the detection of silent and motionless prey resting directly on foliage due to the masking effects of background echoes [3, 4]. Some bats, however, do successfully perform this seemingly impossible task [5], raising the question-what underlying acoustic and behavioral mechanisms do bats use to solve this conundrum? To address this question, we used biomimetic sonar to record high-resolution measurements of echoes from insects resting on leaves. Based on our echo recordings, we predicted optimal approach angles from which masking echoes can best be avoided. In behavioral experiments, we put these predictions to test. We recorded the prey approach behavior of wild bats in a flight cage equipped with an ultrasonic microphone synchronized with two high-speed cameras for 3D flightpath reconstructions. Bats approached prey from our predicted optimal oblique angles, using the leaf as a specular reflector to uncover previously acoustically hidden prey. Our findings disclose key behavioral and acoustic mechanisms enabling the detection of prey echoes that background clutter would otherwise mask. This work adds to the fundamental understanding of how bat echolocation strategies can override acoustic camouflage by silent, motionless prey, thus providing new insights into the evolutionary arms race between predators and their prey.

Plant species dominance increases pollination complementarity and plant reproductive function.

Worldwide, anthropogenic change is causing biodiversity loss, disrupting many critical ecosystem functions. Most studies investigating the relationship between biodiversity and ecosystem functioning focus on species richness, predominantly within the context of productivity-related functions. Consequently, there is limited understanding of how other biodiversity measures, such as species evenness (the distribution of abundance among species), affect complex multitrophic functions such as pollination. We explore the effect of species evenness on the ecosystem function of pollination using a controlled experiment with selected plants and insects in flight cages. We manipulated the relative abundances of plant and pollinator species, while holding species richness, composition, dominance order, and total abundance constant. Then, we tested how numerical species evenness affected network structure and consequently, seed production, in our artificial communities. Contrary to our expectation, numerical dominance in plant communities increased complementarity in pollinator use (reduced pollinator sharing) among plant species. As predicted by theory, this increased complementarity resulted in higher seed production for the most dominant and rare plant species in our cages. Our results show that in a controlled experimental setting, numerical species evenness can alter important aspects of plant-pollinator networks and plant reproduction, irrespective of species richness, composition, and total abundance. Extending this understanding of how species evenness affects ecosystem functioning to natural systems is crucial as anthropogenic disturbances continue to alter species' abundances, likely disrupting ecosystem functions long before extinctions occur.

Efeito da Utilização de Cama de Aviário como Adubo Orgânico na Qualidade Química e Microbiológica do Solo

A disposicao de cama de aviario no solo de maneira continua e descontrolada pode causar impactos ambientais. Esse estudo teve como objetivo avaliar a influencia da aplicacao de cama de aviario nas caracteristicas quimicas e microbiologicas do solo. A primeira coleta de solo foi realizada dois anos apos a ultima aplicacao de cama de aviario nas areas com cultivo de tifton, milho/aveia, olericolas e mandioca, e na mata nativa. A segunda coleta foi realizada noventa dias apos a aplicacao nos solos com cultivos anuais (tifton e milho/aveia) e na mata nativa. Os dados da primeira coleta foram constituidos de um experimento inteiramente casualizado, e os da segunda coleta por meio de um experimento fatorial 3x2 (usos do solo x tempo de aplicacao). As analises quimicas realizadas foram de macro e micronutrientes, pH, carbono orgânico e saturacao por bases, alem do nitrogenio mineral. As caracteristicas microbiologicas analisadas foram carbono da biomassa microbiana, respiracao basal, quociente metabolico, quociente microbiano e mineralizacao do nitrogenio. A aplicacao de cama de aviario atrelada aos demais fatores relacionados as culturas, teores de argila e manejos dos solos provocou um aumento da saturacao por bases e nas concentracoes de Ca, Mg, K, P e Zn, e reduziu o carbono orgânico e o nitrogenio mineral. O CBMS e a sua atividade diminuiram, e o quociente metabolico aumentou. Os solos da segunda coleta apresentaram valores maiores de RBS, qCO2, N mineral e mineralizacao do nitrogenio. A aplicacao de cama de aviario influenciou as caracteristicas quimicas e microbiologicas do solo.

An Investigation of Associations Between Management and Feather Damage in Canadian Laying Hens Housed in Furnished Cages.

Simple SummaryFeather damage due to feather pecking behaviour remains a serious welfare concern in flocks of egg-laying hens housed in large groups. A better understanding of the farm factors that contribute to feather damage is needed, especially as Canadian egg farming transitions away from conventional cage housing systems and into alternative, larger group systems. This study aimed to explore bird, housing, and management associations with feather damage in Canadian laying hens housed in furnished cage systems. Twenty-six laying hen farms housing birds in furnished cages were surveyed across the country, along with the scoring of feather condition of 50 hens from each flock. Factors found to have an influence on greater feather damage seen in flocks included increasing age, having all brown-feathered hens, the practice of midnight feeding, and hens not having access to a scratching area or additional foraging material. These results support existing evidence that feather damage is the result of multiple factors, with genetics and foraging opportunity being some of the most important. Further research is needed to test the effectiveness of related intervention strategies.Feather pecking is a continuous welfare challenge in the housing of egg-laying hens. Canada is currently making the transition from conventional cages to alternative housing systems. However, feather damage (FD) among laying hens due to feather pecking remains a welfare concern. An explorative approach was taken to assess bird, housing, and management associations with FD in Canadian laying hens housed in alternative systems. A questionnaire focused on housing and management practices was administered to 122 laying farms across Canada in autumn of 2017 (response rate of 52.5%), yielding information on a subset of 26 flocks housed in furnished cages. Additionally, a three-point feather cover scoring system was developed to estimate the prevalence of FD. Farmers assessed FD by sampling 50 birds per flock. Linear regression modeling was applied to explain FD as a function of 6 variables (out of an available 54). Of the 6 modeled variables, “increased age”, “brown feather colour”, “midnight feeding”, and “no scratch area” were associated with higher levels of FD at farm level (R2 = 0.77). The results indicated that FD resulting from feather pecking is a multifactorial problem, and supported existing evidence that FD increases as birds age. These results also suggested that “feather colour”, “midnight feeding”, and “access to (or lack of) a scratch area or additional substrate” play a role in FD prevalence in furnished cages.

A spatial network analysis of resource partitioning between bumblebees foraging on artificial flowers in a flight cage

BackgroundIndividual bees exhibit complex movement patterns to efficiently exploit small areas within larger plant populations. How such individual spatial behaviours scale up to the collective level, when several foragers visit a common area, has remained challenging to investigate, both because of the low resolution of field movement data and the limited power of the statistical descriptors to analyse them. To tackle these issues we video recorded all flower visits (N = 6205), and every interaction on flowers (N = 628), involving foragers from a bumblebee (Bombus terrestris) colony in a large outdoor flight cage (880 m2), containing ten artificial flowers, collected on five consecutive days, and analysed bee movements using networks statistics.ResultsBee-flower visitation networks were significantly more modular than expected by chance, indicating that foragers minimized overlaps in their patterns of flower visits. Resource partitioning emerged from differences in foraging experience among bees, and from outcomes of their interactions on flowers. Less experienced foragers showed lower activity and were more faithful to some flowers, whereas more experienced foragers explored the flower array more extensively. Furthermore, bees avoided returning to flowers from which they had recently been displaced by a nestmate, suggesting that bees integrate memories of past interactions into their foraging decisions.ConclusionOur observations, under high levels of competition in a flight cage, suggest that the continuous turnover of foragers observed in colonies can led to efficient resource partitioning among bees in natural conditions.

Bats tune in to the sound of rain

![Figure][1] Micronycteris microtis with katydid. Photo credit: Inga Geipel. When Inga Geipel, from the Smithsonian Tropical Research Institute in Panama, was watching bats foraging for insects in an outdoor flight cage, she noticed something strange. Every time it started raining, the

A short note on extreme sex ratio in solitary bees Osmia cornuta in semi-field trials testing the impact of neonicotinoids

The widespread prophylactic use of neonicotinoids has severe negative effects on non-target organisms that provide ecosystem services. Chronic neonicotinoid exposure led to a male-biased offspring sex ratio in the solitary bee species Osmia bicornis in laboratory experiments, but semi-field or field data are largely lacking. Here, we used semi-field experiments to investigate the potential impact of the neonicotinoid clothianidin on the sex ratio of the closely related species Osmia cornuta. Male and female individuals of O. cornuta were held in flight cages with fully blooming winter oilseed rape, treated or not with clothianidin. After hibernation, sex ratio of emerging offspring and overwintering mortality was determined. A total of 191 male and 4 female, and 203 male and 2 female O. cornuta emerged in the control and the clothianidin treatment, respectively, thereby clearly showing an extremely male-biased sex ratio. However, there was no significant clothianidin treatment effect. As sex ratio was strongly biased in both, the clothianidin and the control treatment, our data can obviously not explain the underlying mechanism. Such extreme sex ratios require more attention in semi-field studies assessing the impacts of pesticides and other stressors on solitary bees.

The role of pollinator preference in the maintenance of pollen colour variation.

Pollinators often drive the evolution of floral traits, but their capacity to influence the evolution of pollen colour remains unclear. Pollen colour in Campanula americana is variable and displays a longitudinal cline from prevalence of deep purple in western populations to white and light-purple pollen in eastern populations. While selection for thermal tolerance probably underlies darker pollen in the west, factors contributing to the predominance of light pollen in eastern populations and the maintenance of colour variation within populations throughout the range are unknown. Here we examine whether pollinators contribute to the maintenance of pollen colour variation in C. americana. In a flight cage experiment, we assessed whether Bombus impatiens foragers can use pollen colour as a reward cue. We then established floral arrays that varied in the frequency of white- and purple-pollen plants in two naturally occurring eastern populations. We observed foraging patterns of wild bees, totalling >1100 individual visits. We successfully trained B. impatiens to prefer one pollen colour morph. In natural populations, the specialist pollinator, Megachile campanulae, displayed a strong and consistent preference for purple-pollen plants regardless of morph frequency. Megachile also exhibited a bias toward pollen-bearing male-phase flowers, and this bias was more pronounced for purple pollen. The other main pollinators, Bombus spp. and small bees, did not display pollen colour preference. Previous research found that Megachile removes twice as much pollen per visit as other bees and can deplete pollen from natural populations. Taken together, these results suggest that Megachile could reduce the reproductive success of plants with purple pollen, resulting in the prevalence of light-coloured pollen in eastern populations of C. americana. Our research demonstrates that pollinator preferences may play a role in the maintenance of pollen colour variation in natural populations.

Risk factors associated with Chlamydia psittaci infections in psittacine birds and bird handlers.

The aim of this study was to determine the prevalence and potential risk factors associated with Chlamydia psittaci infections in psittacine birds and bird handlers in Egypt. A total of 190 swabs were collected from psittacine birds (n=120) and bird handlers (n=70) and were tested by polymerase chain reaction to detect the C. psittaci ompA gene. Chlamydia psittaci DNA was detected in 63 (52·5%) of 120 samples collected from psittacine birds. The occurrence of C. psittaci infections was high in Cockatiel birds (60%), followed by Fischer's lovebird (51%) and Rosy-faced lovebird (47·5%). Bird age, location (pet markets and households), housing (caged and aviary), and sampling season were considered significant risk factors for C. psittaci infections in psittacine birds. Of the 70 sputum swabs collected from bird handlers, only 4 (6%) were positive for C. psittaci. Positive cases were closely associated with older persons (≥30years) who had respiratory signs and handled birds in pet markets. Further, wearing protective gloves and washing hands when handling psittacine birds decreased the frequency of C. psittaci infections in bird handlers. The prevalence of C. psittaci infections in psittacine birds in Egypt is high, which has a potential threat to human health in this area. Thus, dissemination of effective prevention and control measures is essential to prevent the spread of C. psittaci among psittacine birds, as well as among humans in contact with birds. Results from this study highlighted the risk factors associated with C. psittaci infections in psittacine birds and bird handlers in Egypt and will aid in developing prevention and control measures to reduce the risk of C. psittaci infection.

Cognitive constraints on optimal foraging in frog-eating bats

Animals are expected to optimize energy intake when choosing between different foraging options. A common explanation for deviations from optimal economic decisions is that there is an imperfect relationship between physical reality and an animal's perceptual processes, which can constrain assessment of profitability. One such phenomenon that is apparently ubiquitous across taxa is proportional processing, where a perceived change in a stimulus is proportional to the change in stimulus magnitude. In this study, we investigated whether proportional processing explains how frog-eating bats, Trachops cirrhosus, discriminate between patches of frog choruses that vary in their number of calling frogs. To test this, we created artificial choruses consisting of one to six calling frogs. In the flight cage, we then tested the preference of bats (N = 17) with every pairwise combination of chorus size. We found that while bats generally preferred larger choruses, preferences for larger choruses were better explained by the relative, not absolute, differences in chorus sizes. This indicates that T. cirrhosus is perceptually limited in its ability to discriminate between choruses of varying size as the choruses increase in size. Foragers are likely to be less choosy when choosing among larger patches.

Efficacy of LED-enhanced blue sticky traps combined with the synthetic lure Lurem-TR for trapping of western flower thrips (Frankliniella occidentalis)

Pest monitoring is an important tool for successful integrated pest management programmes. Blue sticky traps are important for monitoring western flower thrips, Frankliniella occidentalis, in greenhouses. However, blue sticky traps have three major weak points: (1) efficacy depends on reflection of light, which varies in intensity with fluctuating light conditions (season, diurnal rhythmic pattern), (2) they reflect broad wavelength pattern not optimally matching with maximum sensitivity of WFT photoreceptors, and (3) they offer no olfactory cues which are important for thrips orientation. This study explored the most attractive wavelength range for WFT using broad range of narrow-bandwidth light-emitting diodes (LEDs) in order to improve the attractiveness of blue sticky traps. Subsequently, trapping efficacy of the most attractive blue LED in combination with blue sticky trap and addition of an attractive lure (Lurem-TR) was evaluated in flight cages under greenhouse conditions. Release-capture studies revealed that LEDs with peak emission of 445 nm were clearly more effective than conventional blue sticky traps. In choice experiments, up to 2.7-fold and in no-choice experiment up to 2.1-fold more WFT were captured by LED-blue sticky traps compared to conventional reflecting blue sticky traps. Lurem-TR improved the performance of blue sticky traps and LED-blue sticky traps 2.3-fold and 2.0-fold, respectively, as compared to those without Lurem-TR. The addition of LEDs and kairomone lure to blue sticky traps seems promising for improving WFT trapping, specifically at low population densities especially during early infestation. However, these results should be further validated under more complex, large field conditions.

Live bird markets in Bangladesh as a potentially important source for Avian Influenza Virus transmission

Live bird markets (LBM) are important for trading poultry in many developing countries where they are being considered hotspots of Avian Influenza Virus (AIV) prevalence and contamination. An active surveillance for Avian Influenza Virus (AIV) was conducted on four species of LBM birds (chickens, ducks, quails and pigeons) from 10 of the largest LBM in Chittagong, Bangladesh, and two species of peri-domestic wild birds (house crow and Asian pied starling) in their direct vicinity from November 2012 until September 2016. Our aim was to identify the scale and annual pattern of AIV circulation in both the LBM birds and the two per-domestic wild bird species living in close proximity of the LBM. In the latter two species, the annual pattern in AIV antibody prevalence was additionally investigated. A total of 4770 LBM birds and 1119 peri-domestic wild birds were sampled. We used rt-PCR for detection of the AIV M-gene and AIV subtypes H5, H7 and H9 from swab samples. We used c-ELISA for AIV antibody detection from serum samples of peri-domestic wild birds. Average AIV prevalence among the four LBM species varied between 16 and 28%, whereas no AIV was detected in peri-domestic wild birds by rt-PCR. In all LBM species we found significantly higher AIV prevalence in winter compared to summer. A similar pattern was found in AIV antibody prevalence in peri-domestic wild birds feeding in the direct vicinity of LBM. For the subtypes of AIV investigated, we found a significantly higher proportion of AIV H5 in LBM chickens and H9 in LBM ducks. No H7 was detected in any of the investigated samples. We conclude that AIV and notably AIV H5 and H9 were circulating in the investigated LBM of Bangladesh with clear seasonality that matched the prevalence of AIV antibodies of peri-domestic wild birds. These patterns show great resemblance to the annual outbreak patterns in Bangladeshi poultry industry. Our data suggest considerable exchange of AIV within and among the four LBM bird species and peri-domestic wild birds, which likely contributes to the maintenance of the AIV problems in Bangladesh. Increasing biosecurity and notably reducing the direct and indirect mixing of various domestic bird species and peri-domestic wild birds and developing all-in-all-out selling systems with regular use of disinfectant are likely to reduce the risk of transmission and spread of AIV, including HPAI.