| trace metals affect early maternal transfer of immune components in the feral pigeon. | maternal early transfers of immune components influence eggs' hatching probability and nestlings' survival. they depend on females' own immunity and, because they are costly, on their physiological state. therefore, trace metals, whether toxic and immunosuppressive (e.g., lead, cadmium, etc.) or necessary and immunostimulant (e.g., zinc, copper, iron, etc.), are likely to affect the amount of immune components transferred into the eggs. it may also vary with plumage eumelanin level, which is kno ... | 2017 | 27153130 |
| immunohistochemical localization of cocaine- and amphetamine-regulated transcript peptide (cartp) in the brain of the pigeon (columba livia) and zebra finch (taeniopygia guttata). | cocaine- and amphetamine-regulated transcript peptides (cartp) are neuropeptides that act as neurotransmitters in the brain of vertebrates. the expression of cartp has been characterized in teleosts, amphibians, and several mammalian species, but comparative data in reptiles and birds are nonexistent. in this study, we show the distribution of immunoreactivity against cart peptides (cartp-ir) in the brains of two bird species: the pigeon (columba livia) and zebra finch (taeniopygia guttata). we ... | 2016 | 27121571 |
| functions of innate and acquired immune system are reduced in domestic pigeons (columba livia domestica) given a low protein diet. | racing pigeons are exposed to and act as carriers of diseases. dietary protein requirement for their maintenance has not been determined experimentally despite their being domesticated for over 7000 years. a maintenance nitrogen (protein) requirement (mnr) for pigeons was determined in a balance study using diets containing 6, 10 and 14% crude protein (cp). then, the effects of feeding the diets were investigated to determine whether they were adequate to sustain innate and acquired immune funct ... | 2016 | 27069640 |
| helminth-bacteria interaction in the gut of domestic pigeon columba livia domestica. | the present paper is an attempt to study the interaction between the helminth parasite and bacteria residing in the gut of domestic pigeon, columba livia domestica. biochemical and molecular characterization of the gut bacterial isolate were done and the isolate was identified as staphylococcus sp. db1 (jx442510). the interaction of staphylococcus sp. with cotugnia cuneata, an intestinal helminth parasite of domestic pigeon was studied on the basis of the difference between 'mean worm burden' of ... | 2016 | 27065609 |
| pigeon's (columba livia) paradoxical preference for the suboptimal alternative in a complex foraging task. | recent research has examined a task in which choice of 1 alternative a provides reinforcement and in addition, allows access to alternative b that also provides reinforcement. however, although initial choice of b also provides reinforcement, it does not also allow access to a. thus, optimal performance would be to always choose a. curiously, salwiczek et al. (2012) reported that adult wrasse (cleaner) fish mastered this task within 50 trials, whereas monkeys and apes had great difficulty with i ... | 2016 | 27064201 |
| correction to gibson, leber, and mehlman (2015). | reports an error in "spatial context learning in pigeons (columba livia)" by brett m. gibson, andrew b. leber and max l. mehlman (journal of experimental psychology: animal learning and cognition, 2015[oct], vol 41[4], 336-342). the article included an incorrect version of figure 1, which was from a pilot study and contained 11 x-shaped distractors and the target. the correct version of the figure is provided in the erratum and shows the seven l-shaped distractors that were used during testing w ... | 2016 | 27054383 |
| distribution of calcium-binding proteins, parvalbumin and calbindin, in the midbrain auditory center (mld) of a pigeon. | immunohistochemical distribution of calcium-binding proteins, parvalbumin (pv) and calbindin (cb), has been studied in the mesencephalic auditory center (mld) of pigeon (columba livia). in the central region of the mld (core, icc), an overlap in distribution of the pvand cb-immunopositive (ip) neurons and neuropil has been observed, with different patterns in the central and peripheral parts. in the peripheral region of the mld (belt, ics, and icx), both neurons and neuropil contained only cb. a ... | 2016 | 27021359 |
| the effect of endoscopic sterilization on reproductive behavior and pair bond maintenance of feral pigeons (columba livia). | problems related to feral pigeons (columba livia) in cities mainly result from their large numbers due to uncontrolled population growth. the aim of this study was to evaluate whether endoscopic guided sterilization affects the reproductive behavior of feral pigeons under experimental conditions, with the intention of assessing this technique as a potential method for feral pigeon population control. | 2016 | 27004497 |
| changes in hippocampal volume and neuron number co-occur with memory decline in old homing pigeons (columba livia). | the mammalian hippocampus is particularly susceptible to age-related structural changes, which have been used to explain, in part, age-related memory decline. these changes are generally characterized by atrophy (e.g., a decrease in volume and number of synaptic contacts). recent studies have reported age-related spatial memory deficits in older pigeons similar to those seen in older mammals. however, to date, little is known about any co-occurring changes in the aging avian hippocampal formatio ... | 2016 | 27003117 |
| molecular shifts in limb identity underlie development of feathered feet in two domestic avian species. | birds display remarkable diversity in the distribution and morphology of scales and feathers on their feet, yet the genetic and developmental mechanisms governing this diversity remain unknown. domestic pigeons have striking variation in foot feathering within a single species, providing a tractable model to investigate the molecular basis of skin appendage differences. we found that feathered feet in pigeons result from a partial transformation from hindlimb to forelimb identity mediated by cis ... | 2016 | 26977633 |
| effect of egg weight on composition, embryonic growth, and expression of amino acid transporter genes in yolk sac membranes and small intestines of the domestic pigeon (columba livia). | the objective of this study was to investigate the effect of egg weight on the composition of the egg, the growth of the embryo, and the expression of amino acid transporter genes in the yolk sac membranes and small intestines of the domestic pigeon (columba livia). a total of 240 fertilized eggs were collected and divided into two groups based on the weight of the eggs, light (le) and heavy (he). the composition of 20 eggs from each group was measured, and the remaining eggs were weighed and pl ... | 2016 | 26957627 |
| localisation of the putative magnetoreceptive protein cryptochrome 1b in the retinae of migratory birds and homing pigeons. | cryptochromes are ubiquitously expressed in various animal tissues including the retina. some cryptochromes are involved in regulating circadian activity. cryptochrome proteins have also been suggested to mediate the primary mechanism in light-dependent magnetic compass orientation in birds. cryptochrome 1b (cry1b) exhibits a unique carboxy terminus exclusively found in birds so far, which might be indicative for a specialised function. cryptochrome 1a (cry1a) is so far the only cryptochrome pro ... | 2016 | 26953791 |
| reducing the availability of food to control feral pigeons: changes in population size and composition. | as feeding by humans is one of the main food resources to pigeons (columba livia), there is general agreement that public education that aims to reduce the food base may be the most feasible way to reduce pigeon abundance. however, except for the classic example of basel, the method has rarely been tested or implemented. we provide results from a 1 year study in the city of barcelona where we tested the effect of public education on pigeon population abundance and composition. | 2017 | 26947574 |
| the differential outcomes effect in pigeons (columba livia): is it truly anticipatory? | we used delay-interval interference to investigate the nature of the differential outcomes effect (doe) in pigeons. birds were trained on a delayed matching-to-sample (dms) task under either common outcome or differential outcome conditions, and then presented with visual interference during the delay period. consistent with previous literature, the common outcomes birds were slower to learn the dms task than the differential outcomes birds. the common outcome birds were also more impaired by th ... | 2016 | 26933892 |
| endocrine consequences of an acute stress under different thermal conditions: a study of corticosterone, prolactin, and thyroid hormones in the pigeon (columbia livia). | in the context of global change, the physiological and hormonal stress responses have received much attention because of their implications in terms of allostasis. however, most studies have focused on glucocorticoids only as the "common" response to stressors while neglecting other endocrine axes and hormones (e.g. prolactin, thyroid hormones) that play a crucial role in metabolic adjustments. interestingly, the responsiveness of all these endocrine axes to stress may depend on the energetic co ... | 2016 | 26924044 |
| multiple cue use and integration in pigeons (columba livia). | encoding multiple cues can improve the accuracy and reliability of navigation and goal localization. problems may arise, however, if one cue is displaced and provides information which conflicts with other cues. here we investigated how pigeons cope with cue conflict by training them to locate a goal relative to two landmarks and then varying the amount of conflict between the landmarks. when the amount of conflict was small, pigeons tended to integrate both cues in their search patterns. when t ... | 2016 | 26908004 |
| monitoring air pollution at mohammedia (morocco): pb, cd and zn in the blood of pigeons (columba livia). | the concentrations of pb, cd and zn were investigated in the blood of pigeons (columba livia) in order to assess the degree of pollution by heavy metal. for this, wild city pigeons were caught at four different locations in mohammedia classified according to their industrial activity and road traffic density. significant difference in heavy metal concentrations were observed between sites studied, the highest lead and cadmium levels were found in industrial area and center town, while the highes ... | 2016 | 26903169 |
| walk or ride? phoretic behaviour of amblyceran and ischnoceran lice. | phoresy is a behaviour where one organism hitches a ride on another more mobile organism. this is a common dispersal mechanism amongst relatively immobile species that specialise on patchy resources. parasites specialise on patchily distributed resources: their hosts. although host individuals are isolated in space and time, parasites must transmit between hosts or they will die with their hosts. lice are permanent obligate ectoparasites that complete their entire life cycle on their host. they ... | 2016 | 26896575 |
| collective decision-making in homing pigeons: larger flocks take longer to decide but do not make better decisions. | social animals routinely are challenged to make consensus decisions about movement directions and routes. however, the underlying mechanisms facilitating such decision-making processes are still poorly known. a prominent question is how group members participate in group decisions. we addressed this question by examining how flocks of homing pigeons (columba livia) decide their homing direction. we released newly formed flocks varying in size and determined the time taken to choose a homing dire ... | 2016 | 26863416 |
| maternal adjustment or constraint: differential effects of food availability on maternal deposition of macro-nutrients, steroids and thyroid hormones in rock pigeon eggs. | in oviparous species like birds, eggs provide the direct environment in which embryos are developing. mothers may adjust different egg components in different ways in reaction to environmental cues either to adjust offspring development or because of constraints. in this study, we investigated the effects of food quality and quantity before and during egg laying on three different aspects of egg quality: macro-nutrients (egg and yolk mass), androgens (testosterone and androstenedione), and thyro ... | 2016 | 26843926 |
| label free molecular sexing of monomorphic birds using infrared spectroscopic imaging. | the absence of sexual dimorphism in many birds often makes sex determination difficult. in particular immature birds and adults of monomorphic species show no external sex characteristics. molecular techniques based on dna hybridization or polymerase chain reaction (pcr) are standard methods for sex identification. however, these methods are expensive and time consuming procedures and require special sample preparation. noninvasive methods for a rapid determination of bird's gender are of increa ... | 2016 | 26838394 |
| trace metals, melanin-based pigmentation and their interaction influence immune parameters in feral pigeons (columba livia). | understanding the effects of trace metals emitted by anthropogenic activities on wildlife is of great concern in urban ecology; yet, information on how they affect individuals, populations, communities and ecosystems remains scarce. in particular, trace metals may impact survival by altering the immune system response to parasites. plumage melanin is assumed to influence the effects of trace metals on immunity owing to its ability to bind metal ions in feathers and its synthesis being coded by a ... | 2016 | 26809976 |
| acute, fatal sarcocystis calchasi-associated hepatitis in roller pigeons (columba livia f. dom.) at philadelphia zoo. | four roller pigeons (columba livia f. dom.) at the philadelphia zoo died suddenly. necropsy examination revealed macroscopic hepatitis. microscopically, the predominant lesions were in liver, characterized with necrosis and mixed cell inflammatory response. sarcocystis calchasi-like schizonts and free merozoites were identified in liver. transmission electron microscopy confirmed that schizonts were in hepatocytes. a few schizonts were in spleen. pcr using s. calchasi-specific primers confirmed ... | 2016 | 26801595 |
| growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (columba livia). | two experiments were conducted to fit growth curves, and determine age-related changes in carcass characteristics, organs, serum biochemical parameters, and gene expression of intestinal nutrient transporters in domestic pigeon (columba livia). in experiment 1, body weight (bw) of 30 pigeons was respectively determined at 1, 3, 7, 14, 21, 28, and 35 days old to fit growth curves and to describe the growth of pigeons. in experiment 2, eighty-four 1-day-old squabs were grouped by weight into 7 gro ... | 2016 | 26787925 |
| context controls access to working and reference memory in the pigeon (columba livia). | the interaction between working and reference memory systems was examined under conditions in which salient contextual cues were presented during memory retrieval. ambient colored lights (red or green) bathed the operant chamber during the presentation of comparison stimuli in delayed matching-to-sample training (working memory) and during the presentation of the comparison stimuli as s+ and s- cues in discrimination training (reference memory). strong competition between memory systems appeared ... | 2016 | 26781056 |
| distribution of calcium-binding proteins in the pigeon visual thalamic centers and related pretectal and mesencephalic nuclei. phylogenetic and functional determinants. | multichannel processing of environmental information constitutes a fundamental basis of functioning of sensory systems in the vertebrate brain. two distinct parallel visual systems - the tectofugal and thalamofugal exist in all amniotes. the vertebrate central nervous system contains high concentrations of intracellular calcium-binding proteins (cabprs) and each of them has a restricted expression pattern in different brain regions and specific neuronal subpopulations. this study aimed at descri ... | 2016 | 26638835 |
| detection and discrimination of complex sounds by pigeons (columba livia). | auditory scene analysis is the process by which sounds are separated and identified from each other and from the background to make functional auditory objects. one challenge in making these psychological units is that complex sounds often continuously differ in composition over their duration. here we examined the acoustic basis of complex sound processing in four pigeons by evaluating their performance in an ongoing same/different (s/d) task. this provided an opportunity to investigate avian a ... | 2016 | 26616672 |
| concept learning set-size functions for clark's nutcrackers. | same/different abstract-concept learning by clark's nutcrackers (nucifraga columbiana) was tested with novel stimuli following learning of training set expansion (8, 16, 32, 64, 128, 256, 512, and 1024 picture items). the resulting set-size function was compared to those from rhesus monkeys (macaca mulatta), capuchin monkeys (cebus apella), and pigeons (columba livia). nutcrackers showed partial concept learning following initial eight-item set learning, unlike the other species (magnotti, katz, ... | 2016 | 26615450 |
| the effect of display timing on change blindness in pigeons (columba livia). | change blindness is a phenomenon in which even obvious changes in a visual scene may go unnoticed. recent research has indicated that this phenomenon may not be exclusive to humans. two experiments investigated change blindness in pigeons, using a variant of the widely-used flicker task to investigate the influence of display timing on change blindness. results indicate that the duration of time during which a stimulus display is visible influences change detection accuracy, with the effect due ... | 2016 | 26609796 |
| evaluation of environmental genotoxicity by comet assay in columba livia. | the concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. the biomonitoring of environmental genotoxicity requires the selection of representative organisms as "sentinels," as well as the development of suitable and sensitive assays, such as those aimed at assessing dna damage. the aim of this stud ... | 2016 | 26608565 |
| pigeons (columba livia) as trainable observers of pathology and radiology breast cancer images. | pathologists and radiologists spend years acquiring and refining their medically essential visual skills, so it is of considerable interest to understand how this process actually unfolds and what image features and properties are critical for accurate diagnostic performance. key insights into human behavioral tasks can often be obtained by using appropriate animal models. we report here that pigeons (columba livia)-which share many visual system properties with humans-can serve as promising sur ... | 2015 | 26581091 |
| transfer of humoural immunity over two generations in urban pigeons. | maternal antibodies (matab) are known to provide passive protection early in life for young vertebrates but their effects on the development of offspring immune response across generations are still unknown. here, we investigated the effects of antigen exposure (keyhole limpet haemocyanin, klh) experienced by urban pigeon (columba livia) females on the amount of antigen-specific antibodies (abs) transferred into the egg yolk of their daughters and on the humoural immune response towards this sam ... | 2015 | 26559513 |
| personality and morphological traits affect pigeon survival from raptor attacks. | personality traits have recently been shown to impact fitness in different animal species, potentially making them similarly relevant drivers as morphological and life history traits along the evolutionary pathways of organisms. predation is a major force of natural selection through its deterministic effects on individual survival, but how predation pressure has helped to shape personality trait selection, especially in free-ranging animals, remains poorly understood. we used high-precision gps ... | 2015 | 26489437 |
| stepwise conceptualization in pigeons. | we explored the relation between concept learning and the number of training exemplars, programmed in a stepwise fashion. eight pigeons (columba livia) were trained via differential food reinforcement to peck 1 of 2 simultaneously displayed color images: benign or malignant human breast tissue samples. in each session, only 1 exemplar from each category was trained. if the learning criterion was achieved in 1 session, then those 2 exemplars were discarded and 2 new exemplars were trained in the ... | 2016 | 26460573 |
| sex-associated differences in trace metals concentrations in and on the plumage of a common urban bird species. | urban areas encompass both favorable and stressful conditions linked with human activities and pollution. pollutants remain of major ecological importance for synanthropic organisms living in the city. plumage of urban birds harbour trace metals, which can result from external deposition or from internal accumulation. external and internal plumage concentrations likely differ between specific trace metals, and may further differ between males and females because of potential sex-linked different ... | 2016 | 26458927 |
| asymmetric visual input and route recapitulation in homing pigeons. | pigeons (columba livia) display reliable homing behaviour, but their homing routes from familiar release points are individually idiosyncratic and tightly recapitulated, suggesting that learning plays a role in route establishment. in light of the fact that routes are learned, and that both ascending and descending visual pathways share visual inputs from each eye asymmetrically to the brain hemispheres, we investigated how information from each eye contributes to route establishment, and how in ... | 2015 | 26446810 |
| bird richness and abundance in response to urban form in a latin american city: valdivia, chile as a case study. | there is mounting evidence that urban areas influence biodiversity. generalizations however require that multiple urban areas on multiple continents be examined. here we evaluated the role of urban areas on avian diversity for a south american city, allowing us to examine the effects of urban features common worldwide, using the city of valdivia, chile as case study. we assessed the number of birds and their relative abundance in 152 grid cells of equal size (250 m2) distributed across the city. ... | 2015 | 26422260 |
| comparison of a point-of-care glucometer and a laboratory autoanalyzer for measurement of blood glucose concentrations in domestic pigeons ( columba livia domestica). | biochemical analysis is necessary for diagnosis and monitoring of diseases in birds; however, the small volume of blood that can be safely obtained from small avian species often limits laboratory diagnostic testing. consequently, a suitable methodology requiring only a small volume of blood must be used. this study was designed to compare blood glucose concentrations in domestic pigeons ( columba livia domestica) as measured by a commercial, handheld, human glucometer and a standard autoanalyze ... | 2015 | 26378663 |
| who are the real bird brains? qualitative differences in behavioral flexibility between dogs (canis familiaris) and pigeons (columba livia). | pigeons given a simultaneous spatial discrimination reversal, in which a single reversal occurs at the midpoint of each session, consistently show anticipation prior to the reversal as well as perseveration after the reversal, suggesting that they use a less effective cue (time or trial number into the session) than what would be optimal to maximize reinforcement (local feedback from the most recent trials). in contrast, rats (rattus norvegicus) and humans show near-optimal reversal learning on ... | 2016 | 26364290 |
| change blindness in pigeons (columba livia): the effects of change salience and timing. | change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. recently a parallel change blindness phenomenon has been demonstrated in pigeons. the reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. birds viewed alternating displays of randomly generated lines back-projected onto three response keys, with one ... | 2015 | 26284021 |
| novel cathelicidins from pigeon highlights evolutionary convergence in avain cathelicidins and functions in modulation of innate immunity. | cathelicidins are short cationic host defense peptides and play a central role in host innate immune system. here we identified two novel cathelicidins, cl-cath2 and 3, from columba livia. evolutionary analysis of avian cathelicidins via phylogenetic tree and ka/ks calculations supported the positive selection that prompted evolution of cath2 to cath1 and 3, which originate from common ancestor and could belong to one superfamily. cl-cath2 and 3 both adopt amphipathic α-helical comformations ide ... | 2015 | 26194630 |
| connectivity and neurochemistry of the commissura anterior of the pigeon (columba livia). | the anterior commissure (ac) and the much smaller hippocampal commissure constitute the only interhemispheric pathways at the telencephalic level in birds. since the degeneration study from zeier and karten (), no detailed description of the topographic organization of the ac has been performed. this information is not only necessary for a better understanding of interhemispheric transfer in birds, but also for a comparative analysis of the evolution of commissural systems in the vertebrate clas ... | 2016 | 26179777 |
| spatial context learning in pigeons (columba livia). | in a seminal paper in the cognitive sciences, chun and jiang (1998) described the contextual cueing paradigm in which they used artificial stimuli and showed that people became faster to locate a target when the background predicted the location of a target compared to when it did not. here we examined contextual cueing in pigeons for the first time using artificial stimuli and procedures similar to those of chun and jiang. in the first test, we had pigeons search for a target among a display of ... | 2015 | 26167773 |
| histopathological changes in the kidneys of vertebrate hosts infected naturally and experimentally with paratanaisia bragai (trematoda, digenea). | paratanaisia bragai is a trematode parasite that reaches sexual maturity in the kidney collecting ducts of domesticated and wild fowl and whose intermediate hosts are the snails subulina octona and leptinaria unilamellata. there are some discrepancies in descriptions of the pathology of this parasite in bird kidneys. therefore, the purpose of this study was to analyze the kidneys of rock pigeons (columba livia) naturally infected and of chickens (gallus gallus) experimentally infected with parat ... | 2015 | 26154968 |
| on public influence on people's interactions with ordinary biodiversity. | besides direct impacts of urban biodiversity on local ecosystem services, the contact of city dwellers with urban nature in their everyday life could increase their awareness on conservation issues. in this paper, we focused on a particularly common animal urban species, the feral pigeon columba livia. through an observational approach, we examined behavioral interactions between city dwellers and this species in the paris metropolis, france. we found that most people (mean: 81%) do not interact ... | 2015 | 26154622 |
| cues indicating location in pigeon navigation. | domesticated rock pigeons (columba livia f. domestica) have been selected for returning home after being displaced. they appear to use many of the physical cue sources available in the natural environment for map-and-compass navigation. two compass mechanisms that have been well documented in pigeons are a time-compensated sun compass and a magnetic inclination compass. location-finding, or map, mechanisms have been more elusive. visual landmarks, magnetic fields, odors, gravity and now also inf ... | 2015 | 26149606 |
| releases of surgically deafened homing pigeons indicate that aural cues play a significant role in their navigational system. | experienced homing pigeons with extirpated cochleae and lagenae were released from six sites in upstate new york and western pennsylvania on 17 days between 1973 and 1975 by william t. keeton and his co-workers at cornell university. the previously unpublished data indicate that departure directions of the operated birds were significantly different from those of sham-operated control birds (314 total), indicating that aural cues play an important part in the pigeon's navigational system. moreov ... | 2015 | 26135609 |
| histologic evaluation of critical size defect healing with natural and synthetic bone grafts in the pigeon ( columba livia ) ulna. | fracture and bone segment loss are major clinical problems in birds. achieving bone formation and clinical union in a fracture case is important for the survival of the bird. to evaluate the efficacy of bone grafts for defect healing in birds, 2 different bone grafts were investigated in the healing of a bone defect in 24 healthy pigeons ( columba livia ). in each bird, a 1-cm critical size defect (csd) was created in the left ulna, and the fracture was stabilized with external skeletal fixation ... | 2015 | 26115209 |
| more than one way to see it: individual heuristics in avian visual computation. | comparative pattern learning experiments investigate how different species find regularities in sensory input, providing insights into cognitive processing in humans and other animals. past research has focused either on one species' ability to process pattern classes or different species' performance in recognizing the same pattern, with little attention to individual and species-specific heuristics and decision strategies. we trained and tested two bird species, pigeons (columba livia) and kea ... | 2015 | 26113444 |
| convergent evolution of head crests in two domesticated columbids is associated with different missense mutations in ephb2. | head crests are important display structures in wild bird species and are also common in domesticated lineages. many breeds of domestic rock pigeon (columba livia) have crests of reversed occipital feathers, and this recessive trait is associated with a nonsynonymous coding mutation in the intracellular kinase domain of ephb2 (ephrin receptor b2). the domestic ringneck dove (streptopelia risoria) also has a recessive crested morph with reversed occipital feathers, and interspecific crosses betwe ... | 2015 | 26104009 |
| complete genome sequence of pigeon circovirus detected in racing pigeons in western japan. | we report the genetic analysis of a pigeon circovirus (picv/japan/2/2010) detected in a racing pigeon with diarrheal symptoms in western japan. sequencing revealed a genome size of 2,041 bp that contained 3 open reading frames (orfs), designated v1, c1, and c2, a structure consistent with to those of other pigeon circoviruses. phylogenetic analyses of the orf c1 revealed that picv/japan/2/2010 diverges from other asian pigeon circoviruses, suggesting genetic diversity of pigeon circoviruses in a ... | 2015 | 26066052 |
| sarcocystis calchasi encephalitis in a rock pigeon. | a rock pigeon (columba livia) caught in akihabara, tokyo, showed neurological symptoms, such as head tilt and circling. pathological examinations revealed abundant sarcocystic cysts in the skeletal muscle and myocardium with mild myositis, and numerous schizonts and sarcocysts with severe multifocal granulomatous t-lymphocytic infiltration in the central nervous system. a sarcocystis calchasi-specific gene was detected in the muscle and brain. this case indicates s. calchasi was distributed in j ... | 2015 | 26062567 |
| growth of embryo and gene expression of nutrient transporters in the small intestine of the domestic pigeon (columba livia). | the objective of this study was to investigate the relationship between gene expression of nutrient (amino acid, peptide, sodium and proton) transporters in the small intestine and embryonic growth in domestic pigeons (columba livia). one hundred and twenty-five fertilized eggs were randomly assigned into five groups and were incubated under optimal conditions (temperature of 38.1 °c and relative humidity of 55%). twenty embryos/birds from each group were sacrificed by cervical dislocation on em ... | 2015 | 26055913 |
| pigeons (columba livia) fail to connect dots in learning biological motion. | biological motion point-light displays provide a powerful method for studying motion perception. nonhuman animals are capable of discriminating point-light displays, but it remains unknown how they perceive biological motion in these displays. we trained two groups of pigeons to discriminate video stimuli using two different classification rules. the motion-congruent group was trained to discriminate full-detail and corresponding point-light displays of pigeons from full-detail and point-light d ... | 2015 | 26040957 |
| feather bacterial load shapes the trade-off between preening and immunity in pigeons. | complex communities of bacteria inhabit the feathers of all birds. under normal conditions, individuals maintain a healthy state by defending themselves against these potential invaders by preening. the immune system is only triggered when bacteria gain access into the body. preening is, however, costly and may trade-off with investment in the immune system. to shed light on how birds balance the trade-off between immunity and preen secretions when facing high or low feather bacterial load, we e ... | 2015 | 25881311 |
| defensive behaviors and prosencephalic neurogenesis in pigeons (columba livia) are affected by environmental enrichment in adulthood. | neurogenesis in the adult brain appears to be phylogenetically conserved across the animal kingdom. in pigeons and other adult non-oscine birds, immature neurons are observed in several prosencephalic areas, suggesting that neurogenesis may participate in the control of different behaviors. the mechanisms controlling neurogenesis and its relevance to defensive behaviors in non-oscine birds remain elusive. herein, the contribution of the environment to behavior and neurogenesis of pigeons was inv ... | 2016 | 25869276 |
| endoscopic vasectomy of male feral pigeons (columba livia) as a possible method of population control. | to evaluate whether single-entry endoscopic vasectomy of male feral pigeons (columba livia) significantly reduced fertility and would potentially be valuable for control of feral pigeon populations, 252 male feral pigeons were caught in the city of berne and endoscopically vasectomized. in this procedure, approximately 1 cm of the deferent duct was removed bilaterally. rapid, uneventful recoveries occurred in 94% (237/252) of the pigeons, whereas 6% (15/252) died because of complications associa ... | 2015 | 25867661 |
| the maturation of research into the avian hippocampal formation: recent discoveries from one of the nature's foremost navigators. | for more than 30 years, a growing number of researchers have been attracted to the challenge of understanding the neurobiological organization of the avian hippocampal formation (hf) and its relationship to the remarkable spatial cognitive abilities of birds. in this selective review, we highlight recent anatomical and developmental findings that reveal a hf design that defies any simple comparison to the mammalian hippocampus and leaves unanswered the seemingly enduring question of whether a de ... | 2015 | 25850561 |
| distribution of serotonin 5-ht1a-binding sites in the brainstem and the hypothalamus, and their roles in 5-ht-induced sleep and ingestive behaviors in rock pigeons (columba livia). | serotonin 1a receptors (5-ht1ars), which are widely distributed in the mammalian brain, participate in cognitive and emotional functions. in birds, 5-ht1ars are expressed in prosencephalic areas involved in visual and cognitive functions. diverse evidence supports 5-ht1ar-mediated 5-ht-induced ingestive and sleep behaviors in birds. here, we describe the distribution of 5-ht1ars in the hypothalamus and brainstem of birds, analyze their potential roles in sleep and ingestive behaviors, and attemp ... | 2015 | 25843559 |
| efficacy of nicarbazin (ovistop®) in the containment and reduction of the populations of feral pigeons (columba livia var. domestica) in the city of genoa, italy: a retrospective evaluation. | this study describes the results of a retrospective evaluation (8 years: 2005-2012) of the efficacy of the anti-fertility drug, ovistop® nicarbazin (800 ppm) added to corn kernels used to feed non-migratory feral pigeon colonies, columba livia var. domestica, in the city of genoa, italy. the observation interested 4 non-migratory feral pigeon colonies located into well‑defined areas of the city of genoa, italy. three of these colonies were treated for 12 months, with 10 g of drug (ovistop®) prov ... | 2015 | 25842215 |
| phylogenetic analysis of avian paramyxovirus serotype-1 in pigeons in japan. | to understand the epidemiology of avian paramyxovirus serotype-1 (apmv-1) in pigeons in japan, phylogenetic analysis was comprehensively conducted based on partial fusion protein gene using isolate from the surveillance of this virus with previously known japanese pigeon strains. this surveillance was conducted using feces obtained from domestic pigeons collected in 40 prefectures throughout japan from june 2011 to march 2013. from a total of 1,021 samples, a single virus (apmv1/pigeon/japan/kan ... | 2015 | 25797040 |
| [role of adenosine a(2a) receptors of preoptical area in realization of somnogenic effect of protein 70 kda in pigeons]. | in representatives of class of birds (pigeons columba livia) using electrophysiological methods for the first time there was performed analysis of effects of microinjections into the hypothalamic ventrolateral preoptical area (vlpa) of antagonists of the adenosine a(2a) type receptors on the sleep-wale cycle under natural conditions and on realization of somnogenic effect of heat shock protein 70 kda (hsp70). the following has been established: 1) microinjections of adenosine a(2a) receptors ant ... | 2015 | 25782283 |
| pigeons trade efficiency for stability in response to level of challenge during confined flight. | individuals traversing challenging obstacles are faced with a decision: they can adopt traversal strategies that minimally disrupt their normal locomotion patterns or they can adopt strategies that substantially alter their gait, conferring new advantages and disadvantages. we flew pigeons (columba livia) through an array of vertical obstacles in a flight arena, presenting them with this choice. the pigeons selected either a strategy involving only a slight pause in the normal wing beat cycle, o ... | 2015 | 25733863 |
| the complete mitochondrial genome of the ice pigeon (columba livia breed ice). | the ice pigeon is a breed of fancy pigeon developed over many years of selective breeding. in the present work, we report the complete mitochondrial genome sequence of ice pigeon for the first time. the total length of the mitogenome was 17,236 bp with the base composition of 30.2% for a, 24.0% for t, 31.9% for c, and 13.9% for g and an a-t (54.2 %)-rich feature was detected. it harbored 13 protein-coding genes, 2 ribosomal rna genes, 22 transfer rna genes and 1 non-coding control region (d-loop ... | 2015 | 25722036 |
| the complete mitochondrial genome of the jacobin pigeon (columba livia breed jacobin). | the jacobin is a breed of fancy pigeon developed over many years of selective breeding that originated in asia. in the present work, we report the complete mitochondrial genome sequence of jacobin pigeon for the first time. the total length of the mitogenome was 17,245 bp with the base composition of 30.18% for a, 23.98% for t, 31.88% for c, and 13.96% for g and an a-t (54.17 %)-rich feature was detected. it harbored 13 protein-coding genes, 2 ribosomal rna genes, 22 transfer rna genes and 1 non ... | 2015 | 25690052 |
| implicit learning in cotton-top tamarins (saguinus oedipus) and pigeons (columba livia). | there is considerable interest in the conditions under which human subjects learn patterned information without explicit instructions to learn that information. this form of learning, termed implicit or incidental learning, can be approximated in nonhumans by exposing subjects to patterned information but delivering reinforcement randomly, thereby not requiring the subjects to learn the information in order to be reinforced. following acquisition, nonhuman subjects are queried as to what they ha ... | 2015 | 25673101 |
| characterization of the complete mitochondrial genome of the king pigeon (columba livia breed king). | the king pigeon is a breed of pigeon developed over many years of selective breeding primarily as a utility breed. in the present work, we report the complete mitochondrial genome sequence of king pigeon for the first time. the total length of the mitogenome was 17,221 bp with the base composition of 30.14% for a, 24.05% for t, 31.82% for c, and 13.99% for g and an a-t (54.22 %)-rich feature was detected. it harbored 13 protein-coding genes, two ribosomal rna genes, 22 transfer rna genes, and on ... | 2015 | 25648922 |
| toltrazuril does not show an effect against pigeon protozoal encephalitis. | the protozoan parasite sarcocystis calchasi causes a severe neurologic disease in domestic pigeons (columba livia f. dom.) named pigeon protozoal encephalitis. recently, the parasite has also been reported in psittacines causing a virtually identical disease with fatal outcome. so far, an etiological treatment of s. calchasi infections in pigeons or psittacines is unknown. the present study evaluates the effectiveness of the anticoccidian drug toltrazuril against s. calchasi and the influence of ... | 2015 | 25648444 |
| electrophysiological mismatch response recorded in awake pigeons from the avian functional equivalent of the primary auditory cortex. | the neural response to occasional variations in acoustic stimuli in a regular sequence of sounds generates an n-methyl-d-aspartate receptor-modulated event-related potential in primates and rodents in the primary auditory cortex known as mismatch negativity (mmn). the current study investigated mmn in pigeons (columba livia l) through intracranial recordings from field l of the caudomedial nidopallium, the avian functional equivalent of the mammalian primary auditory cortex. auditory evoked fiel ... | 2015 | 25646582 |
| distribution of vesicular glutamate transporter 2 and ionotropic glutamate receptors in the auditory ganglion and cochlear nuclei of pigeons (columba livia). | glutamate is a principal excitatory neurotransmitter in the auditory system. our previous studies revealed localization of glutamate receptor mrnas in the pigeon cochlear nuclei, suggesting the existence of glutamatergic input from the auditory nerve to the brainstem. this study demonstrated localization of mrnas for vesicular glutamate transporter 2 (vglut2) and ionotropic glutamate receptors (ampa, kainate and nmda) in the auditory ganglion (ag) and cochlear nuclei (magnocellular, angular and ... | 2016 | 25639143 |
| the complete mitochondrial genome of the fancy pigeon, columba livia (columbiformes: columbidae). | the fancy pigeons are domesticated varieties of the rock pigeon developed over many years of selective breeding. in the present work, we report the complete mitochondrial genome sequence of fancy pigeon for the first time. the total length of the mitogenome was 17,233 bp with the base composition of 30.1% for a, 24.0% for t, 31.9% for c, and 14.0% for g and an a-t (54.2 %)-rich feature was detected. it harbored 13 protein-coding genes, 2 ribosomal rna genes, 22 transfer rna genes and 1 non-codin ... | 2015 | 25629469 |
| enterococcus cecorum infection in a racing pigeon. | until now, enterococcus cecorum (ec) has been known as a pathogen for broilers, broiler breeders, and pekin ducks. in the present report, we describe a fatal systemic ec infection in a young racing pigeon (columba livia forma domestica). ec was isolated from the heart, liver, spleen, and intestine of the bird in pure culture. in the pathologic examination, the pigeon showed enteritis and an ulcerative gastritis, which may have been predisposing factors for the development of the generalized ec i ... | 2014 | 25619014 |
| stress-induced core temperature changes in pigeons (columba livia). | changes in body temperature are significant physiological consequences of stressful stimuli in mammals and birds. pigeons (columba livia) prosper in (potentially) stressful urban environments and are common subjects in neurobehavioral studies; however, the thermal responses to stress stimuli by pigeons are poorly known. here, we describe acute changes in the telemetrically recorded celomatic (core) temperature (tc) in pigeons given a variety of potentially stressful stimuli, including transfer t ... | 2015 | 25479572 |
| pigeons produce aerodynamic torques through changes in wing trajectory during low speed aerial turns. | the complexity of low speed maneuvering flight is apparent from the combination of two critical aspects of this behavior: high power and precise control. to understand how such control is achieved, we examined the underlying kinematics and resulting aerodynamic mechanisms of low speed turning flight in the pigeon (columba livia). three birds were trained to perform 90 deg level turns in a stereotypical fashion and detailed three-dimensional (3d) kinematics were recorded at high speeds. applying ... | 2015 | 25452503 |
| an age-related deficit in spatial-feature reference memory in homing pigeons (columba livia). | age-related memory decline in mammals has been well documented. by contrast, very little is known about memory decline in birds as they age. in the current study we trained younger and older homing pigeons on a reference memory task in which a goal location could be encoded by spatial and feature cues. consistent with a previous working memory study, the results revealed impaired acquisition of combined spatial-feature reference memory in older compared to younger pigeons. following memory acqui ... | 2015 | 25449841 |
| gravity anomalies without geomagnetic disturbances interfere with pigeon homing--a gps tracking study. | the gravity vector theory postulates that birds determine their position to set a home course by comparing the memorized gravity vector at the home loft with the local gravity vector at the release site, and that they should adjust their flight course to the gravity anomalies encountered. as gravity anomalies are often intermingled with geomagnetic anomalies, we released experienced pigeons from the center of a strong circular gravity anomaly (25 km diameter) not associated with magnetic anomali ... | 2014 | 25392461 |
| predicting power-optimal kinematics of avian wings. | a theoretical model of avian flight is developed which simulates wing motion through a class of methods known as predictive simulation. this approach uses numerical optimization to predict power-optimal kinematics of avian wings in hover, cruise, climb and descent. the wing dynamics capture both aerodynamic and inertial loads. the model is used to simulate the flight of the pigeon, columba livia, and the results are compared with previous experimental measurements. in cruise, the model unearths ... | 2015 | 25392398 |
| discrimination of complex human behavior by pigeons (columba livia) and humans. | the cognitive and neural mechanisms for recognizing and categorizing behavior are not well understood in non-human animals. in the current experiments, pigeons and humans learned to categorize two non-repeating, complex human behaviors ("martial arts" vs. "indian dance"). using multiple video exemplars of a digital human model, pigeons discriminated these behaviors in a go/no-go task and humans in a choice task. experiment 1 found that pigeons already experienced with discriminating the locomoti ... | 2014 | 25379777 |
| parasite distribution and early-stage encephalitis in sarcocystis calchasi infections in domestic pigeons (columba livia f. domestica). | pigeon protozoal encephalitis is a biphasic, neurologic disease of domestic pigeons (columba livia f. domestica) caused by the apicomplexan parasite sarcocystis calchasi. despite severe inflammatory lesions of the brain, associated parasitic stages have only rarely been identified and the cause of the lesions is still unclear. the aim of this study was therefore to characterize the tissue distribution of s. calchasi within pigeons between the two clinical phases and during the occurrence of neur ... | 2015 | 25338141 |
| [veterinary treatment of pigeon flocks]. | veterinary treatment of pigeon flocks requires specific knowledge on the management of the various pigeon flocks as well as of common diseases in these birds and important diagnostic and therapeutic measures. in this context, it is important to differentiate between racing pigeons, thoroughbreds and pigeons kept for meat production, that is, between food-supplying and companion animals. the following article provides an overview of the species-specific characteristics of columba livia f. domesti ... | 2014 | 25323217 |
| conditioned discrimination of magnetic inclination in a spatial-orientation arena task by homing pigeons (columba livia). | it has been well established that homing pigeons are able to use the earth's magnetic field to obtain directional information when returning to their loft and that their magnetic compass is based, at least in part, on the perception of magnetic inclination. magnetic inclination has also been hypothesized in pigeons and other long-distance navigators, such as sea turtles, to play a role providing positional information as part of a map. here we developed a behavioral paradigm which allows us to c ... | 2014 | 25278470 |
| magnetic field-driven induction of zenk in the trigeminal system of pigeons (columba livia). | magnetoreception remains one of the few unsolved mysteries in sensory biology. the upper beak, which is innervated by the ophthalmic branch of the trigeminal nerve (v1), has been suggested to contain magnetic sensors based on ferromagnetic structures. recently, its existence in pigeons has been seriously challenged by studies suggesting that the previously described iron-accumulations are macrophages, not magnetosensitive nerve endings. this raised the fundamental question of whether v1 is invol ... | 2014 | 25232052 |
| a three-stimulus midsession reversal task in pigeons with visual and spatial discriminative stimuli. | in a two-stimulus visual discrimination task with a reversal in reward contingencies midway through each session, pigeons produce a surprising number of both anticipatory (i.e., before the reversal) and perseverative (i.e., after the reversal) errors. in the current work, we examined pigeons' (columba livia) patterns of responding on a 90-trial, three-stimulus visual or spatial discrimination task with two changes in reward contingency (one after trial 30 and one after trial 60) during each sess ... | 2015 | 25227939 |
| the pigeon (columba livia) model of spontaneous atherosclerosis. | multiple animal models have been employed to study human atherosclerosis, the principal cause of mortality in the united states. each model has individual advantages related to specific pathologies. initiation, the earliest disease phase, is best modeled by the white carneau (wc-as) pigeon. atherosclerosis develops spontaneously in the wc-as without either external manipulation or known risk factors. furthermore, susceptibility is caused by a single gene defect inherited in an autosomal recessiv ... | 2014 | 25214557 |
| the change in heat shock protein expression in avermectin induced neurotoxicity of the pigeon (columba livia) both in vivo and in vitro. | the expression of heat shock proteins (hsps) commonly increases to provide neuroprotection when brain tissues are under stress conditions. residues of avermectins (avms) have neurotoxic effects on a number of non-target organisms. the aim of this study was to investigate the effects of avm exposure on the expression levels of hsp 60, hsp 70 and hsp 90 for pigeon (columba livia) neurons both in vivo and in vitro. the results showed that in general, the mrna and protein levels of hsps were increas ... | 2014 | 25202854 |
| effects of avermectin on microsomal cytochrome p450 enzymes in the liver and kidneys of pigeons. | residues of avermectin (avm) drugs have toxic effects on non-target organisms. analyses of cytochrome p450 enzymes are among the most frequently employed indicators in pharmacology and toxicology studies. in this study, the responses of cytochrome p450 enzymes and pathological changes in the liver and kidney tissues of king pigeons (columba livia) following subchronic exposure to avermectin for 30, 60 and 90d were investigated. dose- and time-dependent decreases in the activities of p450 enzymes ... | 2014 | 25194326 |
| reward context determines risky choice in pigeons and humans. | whereas humans are risk averse for monetary gains, other animals can be risk seeking for food rewards, especially when faced with variable delays or under significant deprivation. a key difference between these findings is that humans are often explicitly told about the risky options, whereas non-human animals must learn about them from their own experience. we tested pigeons (columba livia) and humans in formally identical choice tasks where all outcomes were learned from experience. both speci ... | 2014 | 25165453 |
| transfer between local and global processing levels by pigeons (columba livia) and humans (homo sapiens) in exemplar- and rule-based categorization tasks. | the present experiment investigated pigeons' and humans' processing styles-local or global-in an exemplar-based visual categorization task in which category membership of every stimulus had to be learned individually, and in a rule-based task in which category membership was defined by a perceptual rule. group intact was trained with the original pictures (providing both intact local and global information), group scrambled was trained with scrambled versions of the same pictures (impairing glob ... | 2015 | 25150965 |
| discrimination of holograms and real objects by pigeons (columba livia) and humans (homo sapiens). | the type of stimulus material employed in visual tasks is crucial to all comparative cognition research that involves object recognition. there is considerable controversy about the use of 2-dimensional stimuli and the impact that the lack of the 3rd dimension (i.e., depth) may have on animals' performance in tests for their visual and cognitive abilities. we report evidence of discrimination learning using a completely novel type of stimuli, namely, holograms. like real objects, holograms provi ... | 2014 | 25133466 |
| inhibition of the reproductive system by deslorelin in male and female pigeons (columba livia). | veterinary practitioners frequently encounter disorders of the reproductive system in avian patients. management of these disorders relies on manipulating reproduction by modifying the environment, diet, and social interactions, and by the use of pharmacologic agents and surgery, with varying levels of success and side effects. an alternative is to use the gonadotropin-releasing hormone (gnrh) agonist deslorelin to suppress the pituitary-gonadal axis. to determine the efficacy of deslorelin in d ... | 2014 | 25115038 |
| pigeon (columba livia) and rat (rattus norvegicus) performance in the midsession reversal procedure depends upon cue dimensionality. | pigeons (columba livia) produce many anticipatory and perseverative errors on discrimination tasks with a reversal of reward contingencies partway through the session. prior comparative research has suggested that rats (rattus norvegicus) do not show the same number of errors and produce results that more closely resemble those of humans. we examined pigeons' performance on a visual-spatial discrimination with the reversal point randomized within the session and found that they showed remarkably ... | 2014 | 25111628 |
| age-related spatial working memory deficits in homing pigeons (columba livia). | the hippocampus is particularly susceptible to age-related degeneration that, like hippocampal lesions, is thought to lead to age-related decline in spatial memory and navigation. lesions to the avian hippocampal formation (hf) also result in impaired spatial memory and navigation, but the relationship between aging and hf-dependent spatial cognition is unknown. to investigate possible age-related decline in avian spatial cognition, the current study investigated spatial working memory performan ... | 2014 | 25111336 |
| temporal and contextual consistency of leadership in homing pigeon flocks. | organized flight of homing pigeons (columba livia) was previously shown to rely on simple leadership rules between flock mates, yet the stability of this social structuring over time and across different contexts remains unclear. we quantified the repeatability of leadership-based flock structures within a flight and across multiple flights conducted with the same animals. we compared two contexts of flock composition: flocks of birds of the same age and flight experience; and, flocks of birds o ... | 2014 | 25054203 |
| retinal projection to the pretectal nucleus lentiformis mesencephali in pigeons (columba livia). | in birds, the nucleus of the basal optic root (nbor) and the nucleus lentiformis mesencephali (lm) are retinal-recipient nuclei involved in the analysis of optic flow and the generation of the optokinetic response. the nbor receives retinal input from displaced ganglion cells (dgcs), which are found at the margin of the inner nuclear and inner plexiform layers, rather than the ganglion cell layer. the lm receives afferents from retinal ganglion cells, but whether dgcs also project to lm remains ... | 2014 | 25044056 |
| evidence for perceptual neglect of environmental features in hippocampal-lesioned pigeons during homing. | the importance of the vertebrate hippocampus in spatial cognition is often related to its broad role in memory. however, in birds, the hippocampus appears to be more specifically involved in spatial processes. the maturing of gps-tracking technology has enabled a revolution in navigation research, including the expanded possibility of studying brain mechanisms that guide navigation in the field. by gps-tracking homing pigeons released from distant, unfamiliar sites prior to and after hippocampal ... | 2014 | 25039270 |
| practice makes proficient: pigeons (columba livia) learn efficient routes on full-circuit navigational traveling salesperson problems. | visiting multiple locations and returning to the start via the shortest route, referred to as the traveling salesman (or salesperson) problem (tsp), is a valuable skill for both humans and non-humans. in the current study, pigeons were trained with increasing set sizes of up to six goals, with each set size presented in three distinct configurations, until consistency in route selection emerged. after training at each set size, the pigeons were tested with two novel configurations. all pigeons a ... | 2015 | 24966123 |
| molecular cloning and tissue distribution of peroxisome proliferator-activated receptor-alpha (pparα) and gamma (pparγ) in the pigeon (columba livia domestica). | 1. peroxisome proliferator-activated receptors (ppar) are involved in lipid metabolism through transcriptional regulation of target gene expression. the objective of the current study was to clone and characterise the pparα and pparγ genes in pigeon. 2. the full-length of 1941-bp pparα and 1653-bp pparγ were cloned from pigeons. the two genes were predicted to encode 468 and 475 amino acids, respectively. both proteins contained two c4-type zinc fingers, a nuclear hormone receptor dna-binding re ... | 2014 | 24844133 |
| estimating the surface area of birds: using the homing pigeon (columba livia) as a model. | estimation of the surface area of the avian body is valuable for thermoregulation and metabolism studies as well as for assessing exposure to oil and other surface-active organic pollutants from a spill. the use of frozen carcasses for surface area estimations prevents the ability to modify the posture of the bird. the surface area of six live homing pigeons in the fully extended flight position was estimated using a noninvasive method. an equation was derived to estimate the total surface area ... | 2014 | 24812356 |
| through the eyes of a bird: modelling visually guided obstacle flight. | various flight navigation strategies for birds have been identified at the large spatial scales of migratory and homing behaviours. however, relatively little is known about close-range obstacle negotiation through cluttered environments. to examine obstacle flight guidance, we tracked pigeons (columba livia) flying through an artificial forest of vertical poles. interestingly, pigeons adjusted their flight path only approximately 1.5 m from the forest entry, suggesting a reactive mode of path p ... | 2014 | 24812052 |
| following the sun: a mathematical analysis of the tracks of clock-shifted homing pigeons. | we analysed the tracks of clock-shifted pigeons from six releases to determine how they cope with the conflict between their sun compass and other navigational cues. time-lag embedding was used to calculate the short-term correlation dimension, a parameter that reflects the complexity of the navigational system, and with it, the number of factors involved. initially, while pigeons were still at the release site, the short-term correlation dimension was low; it increased as the birds left the sit ... | 2014 | 24803461 |