Homing Pigeons Research Articles

A cross sectional study on airborne inhalable microorganisms, endotoxin, and particles in pigeon coops – Risk assessment of exposure

Pigeon breeding is associated with symptoms of the airways. The aim of this study is to illuminate the bacteriological and toxicological characteristics of airborne dust in pigeon coops. Airborne dust was sampled in 31 urban pigeon coops with homing and fancy pigeons, and following the dust was characterized. In total 141 different bacterial species were identified using MALDI-TOF MS, and of these 11 species are classified in risk group 2. Of the cultivable bacteria, Staphylococcus equorum was present in the highest concentration. Microorganisms in the dust were able to form biofilm, and the amount correlated positively with the number of bacteria. Next generation sequencing showed 180 genera with Acinetobacter in highest reads. On average 999 ± 225 ZOTUs were observed per sample with a Shannon-Wiener biodiversity index of 6.17 ± 0.24. Of the identified species the following have previously been suggested as causative agents of extrinsic allergic alveolitis: Alcaligenes faecalis, Bacillus subtilis, Pantoea agglomerans, Sphingobacterium spiritivorum, Thermoactinomyces sp., and Streptomyces albus. Staphylococcus was present on particles with sizes between 1.1 and > 7.0 μm with a geometric mean diameter of particles on 4.7 ± 1.1 μm. Concentrations of airborne endotoxin and dust were elevated compared to references, and the geometric mean concentrations were 102 EU/m3 and 1.07 mg dust/m3, respectively. Upon exposure to the airborne dust human granulocytes produced Reactive Oxidative Species during the first 5 min, and then no further reaction was observed. The concentrations of bacteria in general, Staphylococcus spp., and endotoxin and biodiversity were associated significantly with season, temperature and/or relative humidity, but not with type or density of pigeons. The bacterial composition and biodiversity indices were not affected by type of pigeon. In conclusion, the exposure to bacteria and endotoxin in pigeon houses should not be neglected in the evaluation of causative agents of airways symptoms among pigeon breeders.

Pigeons retain partial memories of homing paths years after learning them individually, collectively or culturally.

Memory of past experience is central to many animal decisions, but how long specific memories can influence behaviour is poorly understood. Few studies have reported memories retrieved after several years in non-human animals, especially for spatial tasks, and whether the social context during learning could affect long-term memory retention. We investigated homing pigeons' spatial memory by GPS-recording their homing paths from a site 9 km from their loft. We compared solo flights of naive pigeons with those of pigeons that had last homed from this site 3–4 years earlier, having learnt a homing route either alone (individual learning), together with a naive partner (collective learning) or within cultural transmission chains (cultural learning). We used as a control a second release site unfamiliar to all pigeons. Pigeons from all learning treatments outperformed naive birds at the familiar (but not the unfamiliar) site, but the idiosyncratic routes they formerly used several years before were now partially forgotten. Our results show that non-human animals can use their memory to solve a spatial task years after they last performed it, irrespective of the social context during learning. They also suggest that without reinforcement, landmarks and culturally acquired ‘route traditions' are gradually forgotten.

Externally attached biologgers cause compensatory body mass loss in birds

Abstract Animal‐borne logging devices are now commonly used to record and monitor the movements, physiology and behaviours of free‐living animals. It is imperative that the impacts these devices have on the animals themselves are minimised. One important consideration is the interaction between the body mass of the animal and the mass of the device. Using captive homing pigeons, we demonstrate that birds lose the equivalent amount of body mass compared to that of the logging device attached. With our experiments, we calculated that the compensatory mass loss because of the logging device equates to a total loss of 1,140 kJ of energy to the bird, over the 25‐day period. This equates to 32% per day of their total daily energy budget. We suggest that practitioners of biologging give due consideration to the possibility of a device‐induced decrease in body mass when making decisions regarding device size, and when considering the period of the time of the year at which devices are attached. It appears, based on the results of the present study, that device attachment is likely to be most disruptive during periods of regulated mass change, especially when periods of mass gain precede periods in which stored energy reserves are extensively utilised. These findings have significant consequences for anyone using biologging technology on both wild and captive volant animals. Further studies utilising captive birds are now needed to fully understand how context‐ and species‐dependent physiological responses to externally attached devices are.

Multifocal ulcerative ventriculitis a pigeon by Hadjelia truncata

A single 5-year-old, white homing pigeon (Columba livia domestica) was submitted from a flock of 30 birds. The bird was bright alert and responsive upon presentation. One other bird was sick and two had died. The reported duration of illness was six months. Birds were noted to have a full crop but losing weight.

Evaluation of the antiparasitic activity of the chitosan-silver nanocomposites in the treatment of experimentally infested pigeons with Pseudolynchia canariensis

This study aimed to evaluate the efficacy of chitosan-silver nanocomposites in the treatment of experimentally infested pigeons with Pseudolynchia canariensis (P. canariensis) with evaluation of different immunological parameters before and after treatment. Therefore, fourteen birds were divided into 2 groups; group1(infested group including 12 birds) which subdivided into 6 sub-groups experimentally infested pigeons 2 pigeons each, and five group of them were treated with chitosan-silver nanocomposites and sub-group number 6 was treated with deltamethrin while, group 2 including two pigeons were kept as control negative ones. P. canariensis flies distributed under the wing and /or under the tail in infested group and these pigeons showed significantly lower RBCs and higher WBCs than that in non-infested pigeons. The cell mediated immune response against experimentally infested pigeons with P. canariensis was studied. P. canariensis infestation in pigeons have a negative impact on pigeon’s blood parameters, increase TNF-α and IL-1β cytokines levels. This study cleared out the role of P. canariensis in the induction of a case of oxidative stress indicated by high level of nitric oxide and malondialdehyde (MDA) with low antioxidant capacity in shape of reduced zinc concentration in the sera of experimentally infested pigeon. Chitosan-silver nanocomposite has a promising effect in the elimination of P. canariensis infestation in pigeons.

Occurrence of Diseases in Holdings of Carrier Pigeons with Different Prophylactic Plans

Occurrence of Diseases in Holdings of Carrier Pigeons with Different Prophylactic Plans

Localisation of cryptochrome 2 in the avian retina

Cryptochromes are photolyase-related blue-light receptors acting as core components of the mammalian circadian clock in the cell nuclei. One or more members of the cryptochrome protein family are also assumed to play a role in avian magnetoreception, but the primary sensory molecule in the retina of migratory birds that mediates light-dependent magnetic compass orientation has still not been identified. The mRNA of cryptochrome 2 (Cry2) has been reported to be located in the cell nuclei of the retina, but Cry2 localisation has not yet been demonstrated at the protein level. Here, we provide evidence that Cry2 protein is located in the photoreceptor inner segments, the outer nuclear layer, the inner nuclear layer and the ganglion cell layer in the retina of night-migratory European robins, homing pigeons and domestic chickens. At the subcellular level, we find Cry2 both in the cytoplasm and the nucleus of cells residing in these layers. This broad nucleic expression rather points to a role for avian Cry2 in the circadian clock and is consistent with a function as a transcription factor, analogous to mammalian Cry2, and speaks against an involvement in magnetoreception.

Overall dynamic body acceleration as an indicator of dominance in Homing Pigeons (Columba livia)

The benefits of dominance are well known and numerous, including first access to resources such as food, mates and nesting sites. Less well studied are the potential costs associated with being dominant. Here, the movement of two flocks of domestic Homing Pigeons Columba livia – measured via accelerometry loggers – was recorded over a period of 2 weeks, during which the birds were confined to their lofts. Movement was then used to calculate each individual's daily overall dynamic body acceleration (ODBA, G), which can be used as a proxy for energy expenditure. The dominance hierarchy of the two flocks was determined via group‐level antagonistic interactions, and had a significantly linear structure. The most dominant bird within each flock was found to move significantly more than conspecifics – on average, c. 39% more than the individual with the next highest degree of movement – indicating a possible cost to possessing the top rank within a hierarchy. Despite the dominance hierarchy being highly linear, this was not the case for ODBA, suggesting that energy expenditure may be more reflective of a despotic hierarchy. These results show the potential for the future use of accelerometry as a tool to study the fusion of energetics and behaviour.

CRY1 Gene Polymorphism and Racing Performance of Homing Pigeons.

Simple SummaryThe aim of this study was to detect polymorphism in cryptochrome 1 (CRY1) gene and to estimate associations between genotypes and racing performance in homing pigeons. The AG to TT change in intron seven of CRY1 gene was detected and determined in 129 pigeons. A statistically significant relationship between genotypes and the results of racing was found. The results indicate the possibility of using this polymorphism as a genetic marker in pigeon breeding.Cryptochromes (CRY) are the family of proteins proposed as the putative magnetoreceptor molecules. In birds, among others in pigeons, CRY1 is widely expressed in a retina. Homing pigeons are known for their navigational abilities, and pigeon racing is a popular sport. So, the purpose of this study was to analyze the variability of the nucleotide sequence of the homing pigeon CRY1 gene, spanning the region coding the two amino acids W320 and W374 of Trp-triad, and estimate the relationship between genotypes and the racing performance. Investigations were carried out on 129 pigeons. Analysis of sequencing results indicated the AG to TT change within the seventh intron of CRY1 gene. Genotypes were determined by the forced PCR-RFLP method. The influence of detected polymorphism on the results of racing pigeons in 100–400 km flights was shown. The AG/TT individuals achieved significantly higher (p ≤ 0.05) mean values of ace points (AP) than the AG/AG ones. Regarding the detected nucleotide change localization, the polymorphism may be involved in CRY1 gene expression modulation. The AG to TT change in CRY1 gene may be considered as a potential genetic marker of racing performance in homing pigeons.

Collective attention in navigating homing pigeons: group size effect and individual differences

One prominent feature of collective attention is the so-called ‘group size effect’. Often documented in studies of vigilance by animals foraging gregariously, this effect describes how individual group members are able to reduce their attention to environmental cues (e.g. predators) as group size increases, since the group can pool information from multiple individuals. Despite extensive literature in one context (foraging–vigilance), it remains unclear whether this effect can be observed in other contexts where animals face different informational demands (e.g. navigation). Using a custom-made sensor combining head-mounted inertial measurement unit and back-mounted GPS, we examined head movement, a proxy for visual scanning behaviour, in homing pigeons, Columba livia , flying alone, in pairs and in flocks (ca. 10 individuals). Individual birds' head movements decreased sharply when they switched from solo to paired flights and again when they switched from paired to flock flights. Homing efficiency (or route straightness) did not decrease in parallel with decreasing head movement but continued to increase over repeated flights. We also found systematic individual differences during flock homing flights, where birds positioned more frontally and more centrally in the flock made larger head movements. Moreover, leaders were positioned more frontally and tended to show larger head movements than followers. Decreased head movement by peripheral birds suggested increased attention to the rest of the flock rather than increased individual vigilance (contra ‘the edge effect’). Overall, our results suggest that individual birds reduced their visual scanning during navigation because of the need to attend closely to fellow flock members to maintain flock cohesion. While reduced per capita visual scanning may reduce the amount of environmental information available to individual birds, it is likely to be compensated by the flock's collective attention. • The group size effect in attention was examined in the context of navigation. • We measured head movement of homing pigeons using a custom-made sensor. • Pigeons flew alone, in pairs, and in flocks (∼10 individuals). • Pigeons decreased their head movement sharply as the flock size increased. • This effect was likely driven by individuals' efforts to maintain flock cohesion.

Application of PCR-HRM method for microsatellite polymorphism genotyping in the LDHA gene of pigeons (Columba livia).

High-resolution melting (HRM) is a post-PCR method that allows to discriminate genotypes based on fluorescence changes during the melting phase. HRM is used to detect mutations or polymorphisms (e.g. microsatellites, SNPs, indels). Here, the (TTTAT)3-5 microsatellite polymorphism within intron 6 of the LDHA gene in pigeons was analysed using the HRM method. Individuals (123 homing pigeons) were genotyped using conventional PCR. Birds were classified into groups based on genotype type and the results were tested by qPCR-HRM and verified using sequencing. Based on the evaluated protocol, five genotypes were identified that vary in the number of TTTAT repeat units (3/3, 4/4, 3/4, 4/5, and 5/5). Sequencing have confirmed the results obtained with qPCR-HRM and verified that HRM is a suitable method for identification of three-allele microsatellite polymorphisms. It can be concluded that the high-resolution melting (HRM) method can be effectively used for rapid (one-step) discrimination of the (TTTAT)3-5 microsatellite polymorphism in the pigeon’s LDHA gene.

Collective behaviour: Movement rules under imminent threat

Evading predator attacks requires making rapid decisions. A new study has found that instead of moving towards others, as predicted by classical models of anti-predator behaviour, homing pigeons move away from their flock when faced with an imminent attack.

The problem with pigeons in research and practice: communicating early literacy essentials and foundations in curriculum and instruction

AbstractThe long‐standing research to practice gap and increased interest in scientific literacy instruction has contributed to the oversimplification of what is deemed as foundational skills in US early literacy classrooms. Invoking a homing pigeon metaphor, this article describes the distilling of decades of reading research into a message being received by literacy practitioners, policymakers and families which prioritises phonics instruction, drowning‐out complex and nuanced findings supporting a more comprehensive approach. Grounded in an emergent literacy paradigm and applying a sociocultural approach to literacy in the 21st century with an eye towards equity, this article reframes what is considered ‘foundational’ early literacy teaching and learning to reflect the research base that supports proportional attention to constrained and unconstrained skills through integrated and contextualised instruction. To narrow the enduring research‐to‐practice gap, researchers must build authentic research partnerships with schools and support teacher educators' and teachers' enactment of comprehensive approaches to literacy instruction, curricula and assessment.

GPS-profiling of retrograde navigational impairments associated with hippocampal lesion in homing pigeons

The avian hippocampal formation (HF) is homologous to the mammalian hippocampus and plays a central role in the control of spatial cognition. In homing pigeons, HF supports navigation by familiar landmarks and landscape features. However, what has remained relatively unexplored is the importance of HF for the retention of previously acquired spatial information. For example, to date, no systematic GPS-tracking studies on the retention of HF-dependent navigational memory in homing pigeons have been performed. Therefore, the current study was designed to compare the pre- and post-surgical navigational performance of sham-lesioned control and HF-lesioned pigeons tracked from three different sites located in different directions with respect to home. The pre- and post-surgical comparison of the pigeons’ flight paths near the release sites and before reaching the area surrounding the home loft (4 km radius from the loft) revealed that the control and HF-lesioned pigeons displayed similarly successful retention. By contrast, the HF-lesioned pigeons displayed dramatically and consistently impaired retention in navigating to their home loft during the terminal phase of the homing flight near home, i.e., where navigation is supported by memory for landmark and landscape features. The data demonstrate that HF lesions lead to a dramatic loss of pre-surgically acquired landmark and landscape navigational information while sparing those mechanisms associated with navigation from locations distant from home.

Absence of “selfish herd” dynamics in bird flocks under threat

The "selfish herd" hypothesis1 provides a potential mechanism to explain a ubiquitous phenomenon in nature: that of non-kin aggregations. Individuals in selfish herds are thought to benefit by reducing their own risk at the expense of conspecifics by attracting toward their neighbors' positions1,2 or central locations in the aggregation.3-5 Alternatively, increased alignment with their neighbors' orientation could reduce the chance of predation through information sharing6-8 or collective escape.6 Using both small and large flocks of homing pigeons (Columba livia; n= 8-10 or n= 27-34 individuals) tagged with 5-Hz GPS loggers and a GPS-tagged, remote-controlled model peregrine falcon (Falco peregrinus), we tested whether individuals increase their use of attraction over alignment when under perceived threat. We conducted n= 27 flights in treatment conditions, chased by the robotic "predator," and n= 16 flights in control conditions (not chased). Despite responding strongly to the RobotFalcon-by turning away from its flight direction-individuals in treatment flocks demonstrated no increased attraction compared with control flocks, and this result held across both flock sizes. We suggest that mutualistic alignment is more advantageous than selfish attraction in groups with a high coincidence of individual and collective interests (adaptive hypothesis). However, we also explore alternative explanations, such as high cognitive demand under threat and collision avoidance (mechanistic hypotheses). We conclude that selfish herd may not be an appropriate paradigm for understanding the function of highly synchronous collective motion, as observed in bird flocks and perhaps also fish shoals and highly aligned mammal aggregations, such as moving herds.

Body weight and Morphometric traits characterization of Some Nigeria Homing Pigeons (Columbia livia).

Growth traits characterization of Nigeria homing pigeons was done using one hundred and thirty eight (138) birds from three locations (LCT) of different agro-ecological zones in Nigeria [Kebbi (KEB):North West; Ilorin (ILR): North Central and Osogbo (OSG): South West]. Parameters measured were body weight (BW) in gram and morphometric body parameters in cm viz. Head length (HL), beak length (BL), neck length (NL), body length (BL), body girth (BG), wing length (WL), body height (BH), thigh length (TL), drumstick length (DL) and keel length (KL). The results showed that, significant (p<0.05) differences existed between body weight and body parameters measured except BL. ILR pigeons had significantly (p<0.05) higher BW (263.51g) compared to OSG (204.15), but similar (p>0.05) to KEB (249.76g); the morphometric body parameters measured showed that HL, BG and WL values were significantly (p<0.05) higher in ILR; OSG had significantly (p<0.05) higher values for KL, while KEB pigeons had significantly (p<0.05) higher values for BL, NL, BH, TL, DL, and SL. Positive and significant correlations (p<0.01, 0.05) exists between locations, NL, SL and BH; BW was negatively correlated with locations with a significant (0.01) value of -0.58. PCA shows the clustering of growth traits from 18.94 to 25.14% under PC1 and 2, canonical discriminant functions gouped KEB and OSG with 56.60%; ILR and KEB with 43.60% while hierarchical clustering shows that KEB homing piegons are distinct from those of ILR and OSG. This results shows that locations have significant effects on growth traits in Nigeria homing pigeons.

Repeated training of homing pigeons reveals age-dependent idiosyncrasy and visual landmark use

Recent research into the navigational strategies of homing pigeons, Columba livia , in the familiar area has highlighted the phenomenon of route fidelity: birds forming idiosyncratic flight paths to which they are loyal over multiple releases from the same site, and even returning to this path when released from a nearby unfamiliar location. Such results highlight the potential importance of visual landmark cues in the homing process. However, not all birds have been found to produce idiosyncratic routes or show this route-joining behaviour. Here we used birds with and without flight experience to study the formation of idiosyncratic routes when released repeatedly from a single location, followed by two off-route releases with differing topography to see how flight experience and local landmark features can influence navigational strategy in the familiar area. We found that, over the course of 20 sequential releases, birds with greater flight experience tended to form idiosyncratic routes whereas less experienced birds did not show this tendency. When released from nearby sites (from which the birds had not previously been released), a range of navigational strategies were seen, including flying parallel to the learned route (suggestive of a learned compass direction), a direct flight path towards home (again indicative of compass use), rejoining the learned route and following the coastline. These latter strategies are suggestive of landmark usage. Analysis using time lag embedding was also used to assess the off-route releases, and the short-term correlation dimension values produced were also indicative of strategies using one or two factors (landmarks, compass or a combination of these two). Individual birds often showed different strategies at different sites, suggesting that the use of different navigational cues is highly flexible and situationally dependent. • Birds with greater flight experience form idiosyncratic routes more readily. • Multiple homing strategies occur when released close to a familiar site. • Age and site-specific biases occurred in which strategies were used. • Flexibility within individuals was seen in terms of strategy choice and cue use.

Fine-scale changes in speed and altitude suggest protean movements in homing pigeon flights.

The power curve provides a basis for predicting adjustments that animals make in flight speed, for example in relation to wind, distance, habitat foraging quality and objective. However, relatively few studies have examined how animals respond to the landscape below them, which could affect speed and power allocation through modifications in climb rate and perceived predation risk. We equipped homing pigeons (Columba livia) with high-frequency loggers to examine how flight speed, and hence effort, varies in relation to topography and land cover. Pigeons showed mixed evidence for an energy-saving strategy, as they minimized climb rates by starting their ascent ahead of hills, but selected rapid speeds in their ascents. Birds did not modify their speed substantially in relation to land cover, but used higher speeds during descending flight, highlighting the importance of considering the rate of change in altitude before estimating power use from speed. Finally, we document an unexpected variability in speed and altitude over fine scales; a source of substantial energetic inefficiency. We suggest this may be a form of protean behaviour adopted to reduce predation risk when flocking is not an option, and that such a strategy could be widespread.

No detection of SARS-CoV-2 in animals exposed to infected keepers: results ofa COVID-19 surveillance program.

SARS-CoV-2, the causative agent of the COVID-19 pandemic, has rarely been associated with transmission from humans to animals (reverse zoonotic transmission). In this retrospective study, the authors reviewed data obtained from 236 animals, including buffaloes, goats/sheep, horses, carrier pigeons, rabbits, hens, snakes, pigs and cows that were screened for SARS-CoV-2 infection because they had been in contact with their SARS-CoV-2-positive breeder for at least 2 weeks. None of the tested animals were found to be positive. The authors' findings suggest that the risk of reverse zoonotic transmission among bred animals and SARS-CoV-2-positive breeders is very low or nonexistent. Additional studies are warranted.

Evaluation of homing pigeon feather tissue as a biomonitor of environmental metal concentrations in China.

Biomonitoring provides direct evidence of the bioavailability and accumulation of toxic elements in the environment, and homing pigeons have been proposed as a biomonitor of atmospheric pollution. We evaluated metal concentrations in homing pigeon feather tissue as a biomonitoring tool. We measured cadmium, lead, and mercury concentrations in feathers collected from 5-6-yo homing pigeons from Guangzhou, Beijing, and Harbin, China during 2011, and feathers of 1, 5, and 10-yo homing pigeons collected from Guangzhou, Beijing, and Harbin, China during 2015-16. We compared metal concentrations in feathers between sexes and among ages and evaluated spatio-temporal differences. Correlations between feather metal concentrations and previously evaluated kidney and liver metal concentrations are reported. There were no significant differences in feather metal concentrations between male and female pigeons or among 1, 5, and 10-yo pigeons. Cadmium, lead, and mercury concentrations in feathers of 1-yo pigeons were significantly correlated with concentrations in liver and kidney tissues, although the correlations were not consistent. Spatio-temporal differences in feather metal concentrations suggest the usefulness of feathers in identifying areas of concern and remedial effectiveness. Homing pigeon feather metal concentrations appear to be useful as a screening biomonitoring tool.