Publications

prey species as possible sources of pbde exposures for peregrine falcons (falco peregrinus) nesting in major california cities.	our earlier findings indicate that (1) peregrine falcons (falco peregrinus anatum bonaparte) nesting in major california cities have among the highest polybrominated diphenyl ether (pbde) levels in the world (max ∑pbdes=100 ppm), and (2) big city peregrines have higher levels and proportions of the higher-brominated congeners (hepta- to deca-bdes) than do their coastal counterparts. in this study we classified the prey species (n =185) from the remains of prey (feathers) at 38 peregrine nest sit ...	2011	20514482
epidemiology of west nile in europe and in the mediterranean basin.	in the last 30 years several cases of west nile (wn) virus infection were reported in horses and humans in europe and in the mediterranean basin. most of them were determined by strains of the lineage 1 included in the european mediterranean/kenyan cluster. strains of this cluster are characterised by a moderate pathogenicity for horses and humans and limited or no pathogenicity for birds. in recent years, however, wn cases determined by strains grouped in the israeli/american cluster of lineage ...	2010	20517490
navigation-induced zenk expression in the olfactory system of pigeons (columba livia).	a large body of evidence indicates that pigeons use olfactory cues to navigate over unfamiliar areas with a differential contribution of the left and right hemispheres. in particular, the right nostril/olfactory bulb (ob) and left piriform cortex (cpi) have been demonstrated to be crucially involved in navigation. in this study we analysed behaviour-induced activation of the olfactory system, indicated by the expression of the immediate early gene zenk, under different homing conditions. one exp ...	2010	20529114
asymmetry of different brain structures in homing pigeons with and without navigational experience.	homing pigeons (columba livia f.d.) are well-known for their homing abilities, and their brains seem to be functionally adapted to homing as exemplified, e.g. by their larger hippocampi and olfactory bulbs. their hippocampus size is influenced by navigational experience, and, as in other birds, functional specialisation of the left and right hemispheres ('lateralisation') occurs in homing pigeons. to show in what way lateralisation is reflected in brain structure volume, and whether some lateral ...	2010	20543120
screening for several potential pathogens in feral pigeons (columba livia) in madrid.	pathogens with the zoonotic potential to infect humans, such as campylobacter jejuni, campylobacter coli and chlamydophila psittaci, can be found in feral pigeons (columba livia). given the high density of these birds in the public parks and gardens of most cities, they may pose a direct threat to public health.	2010	20569487
differential impact of west nile virus on california birds.	the strain of west nile virus (wnv) currently epidemic in north america contains a genetic mutation elevating its virulence in birds, especially species in the family corvidae. although dead american crows (corvus brachyrhynchos) have been the hallmark of the epidemic, the overall impact of wnv on north america's avifauna remains poorly understood and has not been addressed thoroughly in california. here, we evaluate variation by species in the effect of wnv on california birds from 2004 to 2007 ...	2009	20589226
antibiotic resistance in faecal bacteria (escherichia coli, enterococcus spp.) in feral pigeons.	to determine the presence of antibiotic-resistant faecal escherichia coli and enterococcus spp. in feral pigeons (columba livia forma domestica) in the czech republic.	2010	20602656
characterization of the complete mitochondrial genome of the rock pigeon, columba livia (columbiformes: columbidae).	the rock pigeon (columba livia), or rock dove, is a member of the bird family columbidae. we mapped the complete mitochondrial genome of the rock pigeon. the mitochondrial genome of this species is a circular molecule of 17,229 bp in length, encoding a standard set of 13 protein-coding genes, two ribosomal rna genes, and 22 transfer rna genes, plus a putative control region, demonstrating a structure very similar to that of other birds. as found in other vertebrates, most of these genes are code ...	2010	20603809
metastatic melanoma appearing to originate from the beak of a racing pigeon (columba livia).	a 12-year-old male pigeon (columba livia) was reported to have a small lesion on the lower beak, which was diagnosed as malignant melanoma. after surgery to remove it, the general condition of the bird worsened and the bird died. post mortem examination revealed gross, black-colored lesions in the liver, kidney, spleen, and femur bone marrow. lesions were not found in the adrenals. histopathologically, the neoplastic cells had a large amount of melanin pigment and showed severe anisokaryosis and ...	2010	20608548
an adaptive annual rhythm in the sex of first pigeon eggs.	when the reproductive value of male and female offspring varies differentially, parents are predicted to adjust the sex ratio of their offspring to maximize their fitness (trivers and willard, science 179:90-92, 1973). two factors have been repeatedly linked to skews in avian offspring sex ratio. first, laying date can affect offspring sex ratio when the sexes differ in age of first reproduction, such that the more slowly maturing sex is overproduced early in the season. second, position of the ...	2010	20730075
mutagenesis of tgcn5 core region reveals two critical surface residues f90 and r140.	tetrahymena general control non-derepressor 5 (tgcn5) is a critical regulator of gene transcription via acetylation of histones. since the acetylation ability has been attributed to the "core region", we perform mutagenesis of residues within the tgcn5 "core region" in order to identify those critical for function and stability. residues that do not participate in catalysis are identified, mutated and characterized for activity, structure and thermodynamic stability. variants i107v, q114l, a121t ...	2010	20732305
pineal-adrenal interactions in domestic male pigeon exposed to variable circadian light regimes and exogenous melatonin.	this study was aimed to see the histophysiological changes of the pineal and adrenal glands under altered photoperiodic conditions due to the administration of melatonin in the male domestic pigeon, columba livia gmelin.	2010	20799855
effect of a commercial paratyphus vaccine on the development of pigeon circovirus infection in young pigeons (columba livia domestica).	infection with pigeon circovirus (picv) has been associated with young pigeon disease syndrome (ypds), which is considered to be a multifactorial disease. the factors that determine whether birds succumb to clinical disease are not known. to evaluate the potential effect of vaccination with a commercial paratyphus vaccine on the progression of picv infection in young pigeons, forty 6-week-old pigeons naturally infected with picv were randomly assigned to two equal groups. the pigeons of one grou ...	2010	20806655
group decisions and individual differences: route fidelity predicts flight leadership in homing pigeons (columba livia).	how social-living animals make collective decisions is currently the subject of intense scientific interest, with increasing focus on the role of individual variation within the group. previously, we demonstrated that during paired flight in homing pigeons, a fully transitive leadership hierarchy emerges as birds are forced to choose between their own and their partner's habitual routes. this stable hierarchy suggests a role for individual differences mediating leadership decisions within homing ...	2011	20810431
high-throughput gender identification of three columbidae species using melting curve analysis.	the objective was to perform high-throughput gender identification of three columbidae species (columba livia, columba pulchricollis, and streptopelia tranquebarica). although the chromo-helicase-dna binding protein (chd)-based griffiths p2/p8 primer set resolved the amplicon products of these species in 3% agarose gel electrophoresis, it was unsuitable for molecular gender identification using the melting curve analysis (mca) curve for high-throughput analysis. after sequencing the chd-z and ch ...	2011	20833415
route selection by pigeons (columba livia) in "traveling salesperson" navigation tasks presented on an lcd screen.	navigation tasks using the "traveling salesperson problem (tsp)" were presented to pigeons (columba livia) to determine their strategy on spatial tasks with 2 to 3 goals. in experiment 1, a simple tsp task with 2 goals was presented. in experiment 2, 3 goals were presented so that each of the goals and the starting location of the target held each corner of a square. in experiment 3, 3 goals were aligned along a straight line. in experiment 4, 3 goals were placed so that the 2 of them were in cl ...	2010	20836595
topographic arrangement of the rotundo-entopallial projection in the pigeon (columba livia).	the tectofugal pathway (retina--optic tectum--nucleus rotundus--entopallium) is a prominent route mediating visual discrimination in diurnal birds. several lines of evidence have shown that at the tecto-rotundal stage this pathway is composed of multiple parallel channels. anatomical studies show that the nucleus rotundus is composed of at least four subdivisions, according to differences in cytoarchitectonic, histochemical, and hodological properties. each of these subdivisions is in receipt of ...	2010	20853511
effects of immune supplementation and immune challenge on oxidative status and physiology in a model bird: implications for ecologists.	one route to gain insight into the causes and consequences of ecological differentiation is to understand the underlying physiological mechanisms. we explored the relationships between immunological and oxidative status and investigated how birds cope physiologically with the effects of immune-derived oxidative damage. we successively implemented two experimental manipulations to alter physiological status in a model bird species: the homing pigeon (columba livia). the first manipulation, an imm ...	2010	20889833
a slowing effect on visual search by advance information in pigeons (columba livia): a comparison with humans (homo sapiens).	a comparative study was conducted to investigate whether the search for a target letter was facilitated when the target and prime (preceding stimulus) letters were identical. pigeons (section 2) and human participants (section 3) were first trained to search for "a" among "y"s and "e" among "d"s in a condition in which a square shape appeared as the prime (neutral condition). in subsequent testing, a prime was identical either to the corresponding target (target-priming condition) or to the dist ...	2010	20920555
unusual biphasic disease in domestic pigeons (columba livia f. domestica) following experimental infection with sarcocystis calchasi.	a novel sarcocystis species has recently been reported in the domestic pigeon (columba livia f. domestica) as intermediate host, causing severe central nervous signs similar to paramyxovirus-1 or salmonella typhimurium var. cop. infection. transmission of the parasite via the northern goshawk (accipiter gentilis) as definitive host has been established. experimental infection of domestic pigeons with sporocysts excreted by experimentally infected northern goshawks reproduced the natural infectio ...	2010	20945785
molecular characterization of avian paramyxovirus type 1 (newcastle disease) viruses isolated from pigeons between 2000 and 2008 in slovenia.	fourteen avian paramyxovirus type 1 (apmv-1; newcastle disease) viruses isolated from dead free-living and domestic pigeons in slovenia between 2000 and 2008 were analyzed by a molecular characterization of a part of the fusion protein gene, which included the region encoding the fusion protein cleavage site. phylogenetic analysis indicated that the slovene pigeon paramyxovirus type 1 (ppmv-1) viruses do not cluster together but instead are divided into two groups--4bi and 4bii--of sublineage 4b ...	2010	20945791
representation of serial order in pigeons (columba livia).	in experiment 1, 2 groups of pigeons were trained to respond to either a 4-item (a→b→c→d) or 5-item (a→b→c→d→e) list. after learning their respective list, half of the subjects were trained on a positive pair with reinforcement provided when pairs were responded to in the order true to that of the original sequence (4-item: b→c; 5-item: b→d). the remaining subjects were trained on a negative pair with reinforcement provided for responding to the pairs in the order opposite to that learned in the ...	2010	20973610
[cloning and characterization of caveolin-1 gene in pigeon, columba livia domestica].	caveolins, a class of principal proteins forming the structure of caveolae in plasmalemma, were encoded by caveolins gene family. caveolin-1 gene is a member of caveolins gene family. in the present study, a full-length of 2605 bp caveolin-1 cdna sequence in columba livia domestica, which included a 537 bp complete orf encoding a 178 amino acids long putative peptide, were obtained by using rt-pcr and race technique. the columba livia domestica caveolin-1 cds shared 80.1% - 93.4% homology with b ...	2010	20979249
use of feathers of feral pigeons (columba livia) as a technique for metal quantification and environmental monitoring.	this study quantifies metal concentrations in washed and unwashed feathers of feral pigeons (columba livia). the material was collected in two different sites: goiânia (capital of goiás state), with high anthropic activities, and jataí (a city in goiás), with low anthropic activities. results revealed that metals such as pb, cr, and cd were deposited in the feathers originating from air and soil (exogenous process). other metals such as cu, fe, mn, and zn, which are part of the tissue constituti ...	2010	20981568
a type of psychopathy in the domestic pigeon.		1945	21005109
virological and molecular epidemiological investigations into the role of wild birds in the epidemiology of influenza a/h5n1 in central thailand.	a serological and virological surveillance program to investigate the hpai h5n1 virus in wild bird populations was undertaken from february 2007 to october 2008. the purpose of the survey was to investigate the infection status in free ranging wild birds in banglane district, nakhon pathom province, central thailand. samples from wild birds were collected every two months. choanal and cloacal swabs, serum and tissue samples were collected from 421 birds comprising 44 species. sero-prevalence of ...	2010	21041042
determination of an oral aflatoxin dose that acutely impairs hepatic function in domestic pigeons (columba livia).	aflatoxin b1 is a common hepatotoxin in birds. the goal of this study was to establish an acute model for hepatotoxicosis and decreased hepatic function in the white carneaux pigeon (columba livia) via oral administration of this mycotoxin. aflatoxin b1 was orally administered at a dose of 3 mg/kg dissolved in dimethyl sulfoxide to 3 groups of pigeons every 24 hours for 2, 4, and 6 consecutive days, respectively. diagnostic modalities used to evaluate hepatic damage and impaired hepatic function ...	2010	21046941
chlamydophila psittaci and toxoplasma gondii infection in pigeons (columba livia) from são paulo state, brazil.	pigeons (columba livia) cohabit with humans in urban and rural areas, representing a public health problem since microorganisms are transmitted through the inhalation of dust from their dry feces (chlamydiosis) and through ingestion of their undercooked or poorly refrigerated meat (toxoplasmosis). this study aimed to evaluate the presence of chlamydophila psittaci and toxoplasma gondii in pigeons from four cities in são paulo state, brazil. c. psittaci was evaluated through hemi-nested polymeras ...	2010	21055877
genetic diversity of newcastle disease viruses isolated from domestic poultry species in eastern china during 2005-2008.	seventy-nine newcastle disease viruses (ndv) isolated from clinical specimens of different poultry species including chickens, pigeons (columba livia), geese and ostriches in eastern china during 2005-2008 were characterized biologically and phylogenetically. the results showed genetic diversity of these viruses: three class i viruses and one genotype i and 12 genotype ii viruses of class ii circulating in chickens were avirulent; four genotype vib viruses isolated from pigeons were moderately v ...	2010	21061026
[study of the protective effects of exogenous heat shock protein 70 kda in the model of sleep deprivation in pigeons columba livia].	electroencephalographic methods were used to study effects of the preparation of the exogenous heat shock protein with molecular mass 70 kda (hsp70i/hsc70) on the time characteristics of sleep and waking, brain temperature, peripheral vasomotor reactions and thoracic muscle contractile activity after the 5-hour sleep deprivation in pigeons (columba livia). the microinjections of hsp70i/hsc70 were performed into the third brain ventricle after the end of sleep deprivation. it was shown that hsp70 ...	2010	21061648
high prevalence of sarcocystis calchasi sporocysts in european accipiter hawks.	the emerging sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (columba livia f. domestica). experimental studies have identified the northern goshawk (accipiter g. gentilis) as final host. phylogenetically closely related european sparrowhawks (accipiter n. nisus) and wood pigeons (columba palumbus) have been found to harbor genetically closely related sarcocystis spp. however, data on the prevalence and potential interspecies ...	2010	21074324
evaluation of the polymorphic d-loop of columba livia in forensic applications.	we report on the polymorphisms exhibited by three hypervariable regions within the d-loop of columba livia (pigeon) mitochondrial dna. a total of 131 samples were taken from 131 randomly selected birds and used in the analyses of snps, a variable number of tandem repeats (vntr) and an str locus using ce. the number of repeats for the vntr ranged from 2 to 8 producing 21 haplotypes, with 54 individuals exhibiting heteroplasmy. the str locus exhibited multiple and continuous repeats within each in ...	2010	21080373
toxoplasma gondii: diagnosis of experimental and natural infection in pigeons (columba livia) by serological, biological and molecular techniques.	this study aimed to diagnose experimental and natural toxoplasma gondii infection in pigeons (columba livia) by serological, biological and molecular techniques. twelve pigeons, free of infection, were inoculated with 50 sporulated oocysts of t. gondii (veg sample) and four remained uninfected controls. four birds (three infected and one control) were euthanized at 15, 30, 45 and 60 days post-infection (dpi), and their tissues were used to perform a bioassay in mice and nested-pcr using b1 gene ...	2010	21184701
seroprevalence of toxoplasma gondii infection in domestic pigeons (columba livia) in guangdong province of southern china.	little information on epidemiology of toxoplasma gondii infection in pigeons was available in people's republic of china. in the present study, sera from 275 pigeons raised in different commercial flocks in guangdong province of southern china were evaluated using modified agglutination test (mat). specific antibodies were found in sera of 8.7% of 275 pigeons (mat titer ≥ 1:5), and the seropositivity of eight herds we surveyed varied ranging from 0 to 18.2%. the results demonstrated the circulat ...	2010	21208745
conceptual thresholds for same and different in old-(macaca mulatta) and new-world (cebus apella) monkeys.	learning of the relational same/different (s/d) concept has been demonstrated to be largely dependent upon stimulus sets containing more than two items for pigeons and old-world monkeys. stimulus arrays containing several images for use in same/different discrimination procures (e.g. 16 identical images vs. 16 nonidentical images) have been shown to facilitate and even be necessary for learning of relational concepts (flemming et al., 2007; wasserman et al., 2001; young et al., 1997). in the pre ...	2011	21238555
interpreting the effects of image manipulation on picture perception in pigeons (columba livia) and humans (homo sapiens).	the effects of picture manipulations on humans' and pigeons' performance were examined in a go/no-go discrimination of two perceptually similar categories, cat and dog faces. four types of manipulation were used to modify the images. mosaicization and scrambling were used to produce degraded versions of the training stimuli, while morphing and cell exchange were used to manipulate the relative contribution of positive and negative training stimuli to test stimuli. mosaicization mainly removes in ...	2011	21244138
[components of the pigeon tectothalamic visual pathway, revealed with aid of study of cytochrome oxidase and immunoreactivity to calcium-binding proteins].	distribution of activity of cytochrome oxidase (co) and immunoreactivity to parvalbumin (pv) and calbindin (cb) was studied in the optic tectum of the pigeon (columba livia). in the first link of the tectofugal pathway in the central gray layer (sgc = layer 13), small amounts of the co-active and pv-immunoreactive (pv-ir) cellular bodies were revealed in its internal part (sublayer 13b). some of these neurons located along the sgc lower boundary had long dendritic processes ascending into the su ...	2010	21268883
behavioral profile and fos activation of serotonergic and non-serotonergic raphe neurons after central injections of serotonin in the pigeon (columba livia).	central injections of serotonin (5-ht) in food-deprived/refed pigeons evoke a sequence of hypophagic, hyperdipsic and sleep-like responses that resemble the postprandial behavioral sequence. fasting-refeeding procedures affect sleep and drinking behaviors "per se". here, we describe the behavioral profile and long-term food/water intake following intracerebroventricular (icv) injections of 5-ht (50, 150, 300 nmol/2 µl) in free-feeding/drinking pigeons. the patterns of fos activity (fos+) in sero ...	2011	21310184
genetic diversity of avian infectious bronchitis virus isolated from domestic chicken flocks and coronaviruses from feral pigeons in brazil between 2003 and 2009.	to detect the presence of infectious bronchitis virus or avian coronavirus, a nested reverse transcriptase pcr (rt-pcr) method was developed with the aim of amplifying a fragment of 530 bases, comprising the gene coding s1 protein. in the first step, all samples were submitted to rna extraction, rt-pcr, and nested pcr. next, only the positive nested-pcr samples were propagated in specific-pathogen-free (spf) embryonated chicken eggs for virus isolation. positive samples were then sequenced and a ...	2010	21313839
characterization of new medium-chain alcohol dehydrogenases adds resolution to duplications of the class i/iii and the sub-class i genes.	four additional variants of alcohol and aldehyde dehydrogenases have been purified and functionally characterized, and their primary structures have been determined. the results allow conclusions about the structural and evolutionary relationships within the large family of mdr alcohol dehydrogenases from characterizations of the pigeon (columba livia) and dogfish (scyliorhinus canicula) major liver alcohol dehydrogenases. the pigeon enzyme turns out to be of class i type and the dogfish enzyme ...	2011	21329683
prevalence of salmonella spp. antibodies to toxoplasma gondii, and newcastle disease virus in feral pigeons (columba livia) in the city of jaboticabal, brazil.	the rock pigeon (columba livia) may serve as a reservoir for several pathogenic agents that can be transmitted to poultry, wildlife, domesticated pets, and/or humans via excreta, secretions, or dust from feathers. in addition, ingestion of infected pigeons by wild and domestic animals can also transmit these pathogenic agents. the health status of 126 free-living pigeons in an urban area was evaluated by microbiologic culture for salmonella and serologic testing for the presence of antibodies fo ...	2010	21370639
characterization of velogenic newcastle disease viruses isolated from dead wild birds in serbia during 2007.	avian paramyxoviruses type 1 or newcastle disease viruses (ndv) are frequently recovered from wild birds and such isolates are most frequently of low virulence. velogenic ndv are usually recovered from poultry and only occasionally from wild birds. five ndv isolates were obtained from carcasses of four wild bird species during 2007 in serbia: mallard (anas platyrhynchos), eurasian sparrowhawk (accipiter nisus), feral rock pigeon (columba livia), and eurasian collared dove (streptopelia decaocto) ...	2011	21441197
[dynamics of balanced polymorphism morphs in blue rock pigeon (columba livia) from moscow].	analysis of the 30-year dynamics (from 1978 to 2008) of phenotype frequencies in the moscow blue rock pigeon population revealed changes in the frequency distribution of several plumage color phenotypes. the frequency of the melanistic phenotype decreased as a result of the decrease in the total population size and, consequently, population density in colonies. this decrease in the pressure of the melanistic phenotype led to increased proportions of wild-type and aberrantly colored birds through ...	2011	21446187
calcium-binding protein distributions and fiber connections of the nucleus accumbens in the pigeon (columba livia).	until recently, the exact location of the avian nucleus accumbens within the basal forebrain had not been well established (reiner et al. [2004] j comp neurol 473:377-414). while a number of previous studies have shown afferents and efferents of the presumptive "nucleus accumbens," detailed and accurate connection patterns of this newly recognized area are still lacking. we set out to clarify these connections using small, localized injections of cholera toxin subunit b and biotinylated dextran ...	2011	21452202
[activity of cytochrome oxidase in centers of tectofugal and thalamofugal channels of the visual system of pigeon columba livia].	by using a histochemical method of determination of activity of cytochrome oxidase (co), the level of metabolic activity in pigeons has been shown to be higher in centers of the tectofugal visual channel (pretectal nuclei: pr, sp, sp/ips, thalamic nucleus rot, telencephalic entopallidum) than in centers of the thalamofugal visual channel (gld, visual area of the hyperpallium wulst). these data agree with the concept of the dominating role of the tectofugal visual channel in organization of the b ...	2011	21469344
carbonic anhydrase inhibitors: purification and inhibition studies of pigeon (columba livia var. domestica) red blood cell carbonic anhydrase with sulfonamides.	a carbonic anhydrase (ca, ec 4.2.1.1) from red blood cells of pigeons (columba livia var. domestica), clca, was purified to homogeneity. its kinetic parameters for the co(2) hydration reaction were measured. with a k(cat)/k(m) of 1.1 × 10(8) m(-1) s(-1), and a k(cat) of 1.3 × 10(6) s(-1), clca has a high activity, similar to that of the human isoform hca ii. a group of 25 aromatic/heterocyclic sulfonamides incorporating the sulfanilamide, homosulfanilamide, benzene-1,3-disulfonamide, and acetazo ...	2011	21476925
feather keratin gene polymorphism (f-ker) in domestic pigeons.	1. a 525-bp fragment of a feather keratin (f-ker) gene was amplified. four pcr products were sequenced. 2. two substitutions in the amplified region were observed, one of them in the coding region of the gene (cysteine to glycine substitution in the protein). a new acrs-pcr test for avai enzyme was designed. a total of 344 domestic pigeons (columba livia var. domestica) were genotyped. 3. there were significant differences in the frequencies of alleles and genotypes between homing and non-homing ...	2011	21491240
fatal columbid herpesvirus-1 infections in three species of australian birds of prey.	we document columbid herpesvirus-1 (cohv-1) infection in two barking owls (ninox connivens), a powerful owl (ninox strenua) and an australian hobby (falco longipennis). antemortem signs of infection were non-specific and the birds either died soon after they were identified as ill or were found dead unexpectedly. gross postmortem findings were also not specific. microscopically, marked to massive splenic and hepatic necrosis with the presence of eosinophilic inclusion bodies in remaining splenoc ...	2011	21495992
susceptibility of pigeons to clade 1 and 2.2 high pathogenicity avian influenza h5n1 virus.	to assess the susceptibility of pigeons (columba livia) to infection with h5n1 high pathogenicity avian influenza virus (hpaiv), four groups of 1-yr-old and 4-wk-old racing pigeons (10 birds in each group) were inoculated oculonasally with 106 50% egg infectious dose (eid50) of a/crested eagle/belgium/01/2004 (clade 1) or a/swan/poland/305-135v08/2006 (clade 2.2). contact specific-pathogen-free (spf) chickens were kept in the same isolators as young pigeons (two chickens per group). at 3, 5, 7, ...	2011	21500645
cryptosporidium spp. in pet birds: genetic diversity and potential public health significance.	to characterize the prevalence and assess the zoonotic transmission burden of cryptosporidium species/genotypes in pet birds in henan, china, 434 fecal samples were acquired from 14 families of birds in pet shops. the overall prevalence of cryptopsoridium was 8.1% (35/434) by the sheather's sugar flotation technique. the cryptosporidium-positive samples were analyzed by dna sequence analysis of the small subunit (ssu) rrna gene. three cryptosporidium species and two genotypes were identified, in ...	2011	21557938
aerodynamics of tip-reversal upstroke in a revolving pigeon wing.	during slow flight, bird species vary in their upstroke kinematics using either a 'flexed wing' or a distally supinated 'tip-reversal' upstroke. two hypotheses have been presented concerning the function of the tip-reversal upstroke. the first is that this behavior is aerodynamically inactive and serves to minimize drag. the second is that the tip-reversal upstroke is capable of producing significant aerodynamic forces. here, we explored the aerodynamic capabilities of the tip-reversal upstroke ...	2011	21562173
sunk cost: pigeons (<i>columba livia</i>), too, show bias to complete a task rather than shift to another.	the sunk cost effect involves the bias to stay with an alternative because one has already invested resources, even when there is a better alternative available. in a series of experiments, at various points during a 30-peck requirement, pigeons (columba livia) could choose between completing the response requirement (at a different location in experiment 1 or the same location in experiments 3 and 4) and switching to a constant number of pecks. in three experiments, the pigeons showed a bias to ...	2011	21574688
flexible serial response learning by pigeons (columba livia) and humans (homo sapiens).	experimental tasks designed to involve procedural memory are often rigid and unchanging, despite many reasons to expect that implicit learning processes can be flexible and support considerable variability. a version of the serial response time (srt) task was developed, in which the locations of targets were probabilistically determined. targets appeared in locations according to both a structured sequence and a cue validity parameter, and the time to respond to each target was measured. pigeons ...	2011	21574691
flexible learning and use of multiple-landmark information by pigeons (columba livia) in a touch screen-based goal searching task.	three touch screen-based experiments were conducted to investigate whether pigeons would learn to use configural information about a goal's location in relation to a multiple-landmark array. in experiment 1, 4 pigeons (columba livia) were trained to peck a computer monitor at a location that constituted the third vertex of a hypothetical triangle defined by 2 different landmarks. the landmarks appeared in 3 orientations during the training, and the pigeons' goal-searching ability easily transfer ...	2011	21574692
evidence that the human pathogenic fungus cryptococcus neoformans var. grubii may have evolved in africa.	most of the species of fungi that cause disease in mammals, including cryptococcus neoformans var. grubii (serotype a), are exogenous and non-contagious. cryptococcus neoformans var. grubii is associated worldwide with avian and arboreal habitats. this airborne, opportunistic pathogen is profoundly neurotropic and the leading cause of fungal meningitis. patients with hiv/aids have been ravaged by cryptococcosis - an estimated one million new cases occur each year, and mortality approaches 50%. u ...	2011	21589919
prevalence and chemo-therapeutical investigations of gastrointestinal nematodes in domestic pigeons in lahore, pakistan.	the prevalence of gastrointestinal nematodes was studied in 143 (80 male and 63 female) domestic pigeons. faecal samples were collected to determine the gastrointestinal nematodes of domestic pigeons through qualitative and quantitative faecal examinations. a total of 48 (male 33 and 25 female) naturally infected domestic pigeons were divided into g1 (albendzdole) and g2 (fenbendazole) treatment-groups along with one control group (c). the overall prevalence of gastrointestinal nematodes was 40. ...	2011	21602775
induction of zenk protein expression within the nucleus taeniae of the amygdala of pigeons following tone and shock stimulation.		2011	21603778
prevalence of toxoplasma gondii infection in wild birds in durango, mexico.	abstract there is a lack of information concerning the prevalence of toxoplasma gondii infection in wild birds in mexico. in the present study serum samples and tissues from 653 birds from durango state, mexico were evaluated for t. gondii infection. antibodies to t. gondii (modified agglutination test, mat, titer 1:25 or higher) were found in 17 (2.6%) of the 653 birds including 1 of 2 curve-billed thrashers (toxostoma curvirostre), 2 (1 anas platyrhynchos, 1 anas diazi) of 4 ducks, 1 of 2 eagl ...	2011	21612413
do secretions from the uropygial gland of birds attract biting midges and black flies?	bird susceptibility to attacks by blood-sucking flying insects could be influenced by urogypial gland secretions. to determine the effect of these secretions on biting midges and black flies, we set up a series of tests. first, we placed uropygial gland secretions from blue tit cyanistes caeruleus broods inside empty nest boxes while empty nest boxes without gland secretions were treated as controls. blue tit broods, from which we had obtained uropygial secretions, were affected by biting midges ...	2011	21614548
prevalence of toxoplasma gondii antibodies in domestic (columba livia domestica) and wild (columba livia livia) pigeons in niğde region, turkey.	objective: the present study was conducted to investigate the prevalence of toxoplasma gondii specific antibodies in domestic (columba livia domestica) and wild (columba livia livia) pigeons between october 2003-june 2004. methods: blood samples were collected from 216 pigeons, consisting of 105 (55 female, 50 male) domestic pigeons and 111 (53 female, 58 male) wild pigeons. the sera were tested for t. gondii antibodies using the sabin feldman dye test (sfdt). results: one of the 105 (0.95%) dom ...	2011	21618187
immunohistochemical localization of vesicular glutamate transporter 2 (vglut2) in the central nervous system of the pigeon (columba livia).	glutamatergic neurons are distributed widely in the telencephalic pallium of birds, but their targets are unknown. in the present study, a polyclonal antibody was produced against pigeon vesicular glutamate transporter 2 (vglut2) and was used for western blot and immunohistochemistry to detect projection targets of glutamatergic neurons in the pigeon central nervous system. the molecular weight of vglut2 was measured at 65 kda. vglut2 immunoreactivity was observed in neuropil, but not in neurona ...	2011	21618220
the origins of species-specific facial morphology: the proof is in the pigeon.	one of the principal objectives of developmental research is to understand morphogenesis and in doing so, gain insights into the genetic basis of variation observed throughout the animal kingdom. in this review we take an approach, first popularized by darwin, to understanding how diversity is created by using the domesticated pigeon as a model organism. nearly 3000 years of selective breeding has produced an astonishing array of feather patterns, behaviors, skeletal shapes, and body sizes. cumu ...	2007	21672843
the broad range of contractile behaviour of the avian pectoralis: functional and evolutionary implications.	wing-assisted incline running (wair) in birds combines the use of the wings and hindlimbs to ascend otherwise insurmountable obstacles. it is a means of escape in precocial birds before they are able to fly, and it is used by a variety of juvenile and adult birds as an alternative to flight for exploiting complex three-dimensional environments at the interface of the ground and air. wair and controlled flapping descent (cfd) are the bases of the ontogenetic-transitional wing hypothesis, wherein ...	2011	21697427
flexible route selection by pigeons (columba livia) on a computerized multi-goal navigation task with and without an "obstacle".	the ability to select efficient routes while reaching several locations, in situations addressed as the "traveling salesperson problem (tsp)", seems to play an important role in the lives of nonhuman species as well as humans. one of our previous studies with pigeons (columba livia) used different variations of computerized navigation tasks to move a target to one or more goals, and showed that the birds consistently exhibited tendencies to visit the nearest goal first (miyata & fujita, 2010). i ...	2011	21707140
septal area lesions impair spatial working memory in homing pigeons (columba livia).	the septo-hippocampal system in birds resembles that of mammals, motivating research into the function of the avian hippocampus while surprisingly little attention has been given to the septum. to investigate a possible role of the avian septum in memory, the effects of septal area lesions on a spatial working memory (spwm) task was tested in homing pigeons. after preoperative training on an analogue eight-arm (feeders) radial maze, now sham-operated control and septal lesioned pigeons were then ...	2011	21742046
physiological trade-offs in self-maintenance: plumage molt and stress physiology in birds.	trade-offs between self-maintenance processes can affect life-history evolution. integument replacement and the stress response both promote self-maintenance and affect survival in vertebrates. relationships between the two processes have been studied most extensively in birds, where hormonal stress suppression is down regulated during molt in seasonal species, suggesting a resource-based trade-off between the two processes. the only species found to differ are the rock dove and eurasian tree sp ...	2011	21795575
Stable panoramic views facilitate snap-shot like memories for spatial reorientation in homing pigeons.	Following spatial disorientation, animals can reorient themselves by relying on geometric cues (metric and sense) specified both by the macroscopic surface layout of an enclosed space and prominent visual landmarks in arrays. Whether spatial reorientation in arrays of landmarks is based on explicit representation of the geometric cues is a matter of debate. Here we trained homing pigeons (Columba livia) to locate a food-reward in a rectangular array of four identical or differently coloured pipe ...	2011	21818360
some causes of the variable shape of flocks of birds.	flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost). particularly amazing in this respect are the aerial displays of huge flocks of starlings (sturnus vulgaris) above the sleeping site at dawn. the causes of this variability are hardly known, however. here we hypothesise that variability of shape increases when there are larger local differences in movement behaviour in the flock. we investigate this hypothesis with the he ...	2011	21829627
telencephalic organization of the olfactory system in homing pigeons (columba livia).	pigeons use olfactory cues to navigate over unfamiliar areas, and any impairment of the olfactory system generates remarkable reduction of homing performance. lesion and deprivation studies suggest a critical involvement of the right nostril and thus, the right olfactory bulb (ob) and the left piriform cortex (cpi) for initial orientation. this functional pattern suggests that ob and cpi are asymmetrically connected with a stronger projection from the right ob to the left cpi. however, the struc ...	2011	21846495
sarcocystis calchasi-associated neurologic disease in a domestic pigeon in north america.	tissue cysts of a protozoan parasite were present in the skeletal muscle of a domestic pigeon (columba livia f. domestica) with neurologic disease in minnesota, usa. the animal had a severe granulomatous meningoencephalitis. the cysts were slender, up to 1 mm long and up to 0.03 mm in diameter. the cysts had a smooth wall without projections. size and wall morphology were compatible with sarcocystis calchasi. polymerase chain reaction using s. calchasi-specific primers resulted in a specific amp ...	2011	21848932
[Peculiarities of secondary structure of serum albumin of some representatives of the animal kingdom].	Methods of infrared (IR) spectroscopy and circular dichroism (CD) are suitable techniques for detection of proteins structural changes. These methods were used for determinating peculiarities of the secondary structure of serum albumins in some representatives of two classes of reptiles: Horsfield's tortoise (Testudo horsfieldi), water snake (Natrix tessellata) and grass snake (Natrix natrix) and birds: domestic goose (Anser anser), domestic chicken (Gallus domesticus), domestic duck (Anas platy ...	2011	21888056
finding the best angle: pigeons (columba livia) weight angular information more heavily than relative wall length in an open-field geometry task.	pigeons were trained to locate food in two geometrically equivalent corners of a parallelogram-shaped enclosure. both the angular amplitude of the corners and the length of the walls alone were sufficient for successfully completing the task. following training, birds were tested in three separate conditions that manipulated the geometric information available. during tests in both a rectangular-shaped enclosure that preserved the wall length information but not the angular amplitude, and a rhom ...	2011	21918871
prevalence of chlamydia psittaci in the feral pigeon population of basel, switzerland.	feral pigeons (columba livia) are commonly infected with chlamydia psittaci, the agent of psittacosis in humans. to assess the zoonotic risk posed by feral pigeons in the urban environment, we examined the presence of the chlamydia psittaci outer membrane protein a (ompa) gene in pharyngeal and cloacal samples of 202 feral pigeons present in a loft in basel, switzerland. additionally, we examined 620 fresh faecal droppings of feral pigeons at 6 public sites in basel. the ompa gene of c. psittaci ...	2011	21921110
Impact of urban environment and host phenotype on the epidemiology of Chlamydiaceae in feral pigeons (Columba livia).	Chlamydiaceae are obligate intracellular Gram-negative bacteria found all over the world and known to cause various forms of disease in animals and humans. Urban pigeons are known to be an important reservoir of Chlamydia psittaci, the agent of human psittacosis. In this study, we examined the influence of pigeon houses used to regulate pigeon populations and of melanin-based coloration on several epidemiological parameters of Chlamydiaceae in 708 urban pigeons in Paris. We also identified speci ...	2011	21933318
afferent and efferent projections of the mesopallium in the pigeon (columba livia).	the mesopallium is a thick cell plate occupying a substantial portion of the avian dorsal pallium, but its hodology is incompletely known. in pigeons we examined fiber connections of the frontodorsal (mfd) and frontoventral mesopallium (mfv), the ventrolateral mesopallium (mvl), the lateral (mivl) and medial (mivm) parts of the intermediate ventral mesopallium, and the caudal mesopallium (mc). mfv, mivl, and mc connect reciprocally with secondary centers of the trigeminal, tectofugal, and audito ...	2011	21935938
helminth community composition, structure, and pattern in six dove species (columbiformes: columbidae) of south texas.	abstract abstract: the helminth community composition and structure of 6 species of columbids residing in south texas are reported and compared herein. sixty rock pigeons, columba livia (rp), mourning doves, zenaida macroura (md), eurasian collared-doves, streptopelia decaocto (ecd), white-winged doves, zenaida asiatica (wwd), common ground doves, columbina passerina (cgd), and 48 inca doves, columbina inca (id), were collected during the summer of 2006 and examined for helminths. twelve he ...	2011	21955248
biased sex ratio and niche restriction in baruscapillaria obsignata (madsen 1945) (nematoda, capillariidae) from columba livia (aves, columbidae).	in the present study populations of the avian nematode species baruscapillaria obsignata are described from columba livia. male and female individuals were obtained from 27 birds, fixed in alcohol/formalin/acetic acid (afa) and preserved in 70% ethanol. nematodes were identified and then counted under a stereoscopic microscope. baruscapillaria obsignata were much more frequent in the anterior third of the small intestine, and females were more abundant than males in all infra populations. the pr ...	2011	22004684
[avian diversity and bird strike risk at fuyang airport].	from june 2008 to january 2010, a survey of avian communities was conducted in five habitats (grassland, farmland, town, wetland, and woodland) at fuyang airport and its surrounding areas, with the diversity indices in different seasons and different habitats analyzed. a total of 122 avian species belonging to 15 orders and 40 families were recorded. at fuyang airport, the avian species number was significantly higher in summer and autumn than in winter and spring, the avian density was the high ...	2011	22007473
Influenza A virus monitoring in urban and free-ranging pigeon populations in Germany, 2006-2008.	Tracheal and cloacal swabs as well as blood samples from 408 feral urban (Columba livia forma domestica) and 170 free-ranging wood pigeons (Columba palumbus) in Germany were tested for infection with avian influenza viruses (AIVs). Neither influenza A virus was isolated in the swab samples nor influenza A virus RNA detected using real-time reverse transcriptase-PCR (RT-qPCR). In three urban feral pigeons, avian paramyxovirus (APMV) serotype 1 was isolated. Two of 123 serum samples from hunted fr ...	2011	22017045
outbreak of mycobacterium avium subsp. avium infection in one flock of domestic pigeons.	an outbreak of mycobacterium avium subsp. avium infection was diagnosed in one breed of domestic pigeons (columba livia f. domestica) in the czech republic. nodular granulomatous lesions were found in 42 (9.7%) pigeons of the 435 examined; histopathologic examination of livers with gross lesions of mycobacteriosis from 15 randomly selected pigeons revealed granulomatous inflammation typical for avian mycobacteriosis in all samples. direct ziehl-neelsen (zn) microscopy and conventional culture we ...	2011	22017056
possible cues driving context-specific adaptation of optocollic reflex in pigeons (columba livia).	context-specific adaptation (shelhamer m, clendaniel r. neurosci lett 332: 200-204, 2002) explains that reflexive responses can be maintained with different "calibrations" for different situations (contexts). which context cues are crucial and how they combine to evoke context-specific adaptation is not fully understood. gaze stabilization in birds is a nice model with which to tackle that question. previous data showed that when pigeons (columba livia) were hung in a harness and subjected to a ...	2011	22049337
comparison of assessment of pigeon sperm viability by contrast-phase microscope (eosin-nigrosin staining) and flow cytometry (sybr-14/propidium iodide (pi) staining) [evaluation of pigeon sperm viability].	the aim of these experiments was to compare the conventional, microscopic method of evaluating pigeon sperm viability to sperm assessed by flow cytometry. semen was collected twice a week from two groups of pigeons. in every group were 20 males (group i: meat-type breed; group ii: fancy pigeon breed). semen was collected using the lumbosacral and cloacal region massage method. ejaculates collected from each group were pooled and diluted to 10 × 10(6) sperm/ml in bpse solution. samples were divid ...	2012	22056017
plasma and whole brain cholinesterase activities in three wild bird species in mosul, iraq: in vitro inhibition by insecticides.	plasma and brain cholinesterase activities were determined in three wild bird species to assess their exposure to organophosphate and carbamate insecticides which are used in agriculture and public health. in the present study, we used an electrometric method for measurement of cholinesterase activities in the plasma and whole brain of three indigenous wild birds commonly found in northern iraq. the birds used were apparently healthy adults of both sexes (8 birds/species, comprising 3-5 from eac ...	2011	22058655
Indirect evidence for microbiota reduction through dietary mannanoligosaccharides in the pigeon, an avian species without functional caeca.	A feeding trial was conducted to evaluate the effects of mannanoligosaccharides (MOS) on nutrient digestibility, intestinal pH, gut morphology and faecal bacteriology of pigeons, as model for birds without functional caeca. Sixteen adult pigeons (Columba livia domestica) were randomly allotted to either an extruded pellet diet with or without 0.4% MOS. After an adaptation period of 24 days, excreta were collected during 4 days. Apparent nutrient digestibility coefficients were determined using t ...	2011	22074297
diseases of racing pigeon: an update.		1996	22074541
biodiversity and prevalence of parasites of domestic pigeons (columba livia domestica) in a selected semiarid zone of south khorasan, iran.	five species of nematodes and cestodes were collected from alimentary canals of pigeons: the nematodes were two species: ascaridia colombae (16.66%) and hadjelia truncata (1.96%), while the cestodes were cotugnia digonopora (13.79%), raillietina magninumida (18.62%) and raillietina achinobothridia (32.35%); fecal examination revealed: eimeria spp. (40.19%) and cryptosporidium oocysts (2.94%); and blood smears showed: haemoproteus cloumbae (47/05%); in mouth, throat and larynx: trichomonans galli ...	2012	22081317
Serotonin 5-HT(1A) receptor binding sites in the brain of the pigeon (Columba livia).	Present knowledge about the serotonergic system in birdbrains is very limited, although the pigeon was used as an animal model in various studies focused on the behavioral effects of serotonergic transmission. In the mammalian brain the 5-HT(1A) receptor is the most widespread serotonin receptor type, and is involved in various functions. Less is known about the distribution of 5-HT(1A) receptors in the avian species. Therefore, we analyzed serotonin 5-HT(1A) receptor binding sites in the pigeon ...	2012	22100786
The distribution of zebrin immunoreactive purkinje cell terminals in the cerebellar and vestibular nuclei of birds.	Zebrin II (aldolase C) is expressed in a subset Purkinje cells in the mammalian and avian cerebella such that there is a characteristic parasagittal organization of zebrin immunopositive stripes alternating with zebrin immunonegative stripes. Zebrin is not only expressed in the soma and dendrites of Purkinje cells, but also in their axonal terminals. Here, we describe the distribution of zebrin immunoreactivity in both the vestibular and cerebellar nuclei of pigeons (Columbia livia) and hummingb ...	2011	22105608
Identification of shiga toxin and intimin coding genes in Escherichia coli isolates from pigeons (Columba livia) in relation to phylotypes and antibiotic resistance patterns.	Shiga toxin-producing Escherichia coli (STEC) strains are responsible for outbreaks of human intestinal diseases worldwide. Pigeons are distributed in public areas and are potential reservoirs for pathogenic bacteria. One hundred fifty-four fresh fecal samples were obtained from trapped pigeons in southeast of Iran and were cultured for isolation of E. coli. The isolates were examined to determine the prevalence of stx1, stx2, and eae genes, antimicrobial resistance, and their phylotypes. The co ...	2012	22105907
mechanical properties of the avian acrocoracohumeral ligament and its role in shoulder stabilization in flight.	control of movement in the avian shoulder joint is fundamental to understanding the avian wingstroke. the acrocoracohumeral ligament (ahl) is thought to play a key role in stabilizing the glenoid and balancing the pectoralis in gliding flight. if the ahl has to be taut to balance the pectoralis, then it must constrain glenohumeral motion during flapping flight as well. however, birds vary wing kinematics depending on flight speed and behavior. how can a passive ligament accommodate such varying ...	2011	22105988
newcastle disease in the european union 2000 to 2009.	newcastle disease (nd) is a devastating disease of poultry that has to some extent been neglected by those working in the field in the past 10 to 15 years while attention has been focused on the emergence and spread of highly pathogenic avian influenza caused by a h5n1 subtype virus. during 2000 to 2009 in the european union (eu) member states, nd viruses virulent for chickens have been detected in wild birds, domesticated pigeons and poultry. based on these isolations it appears that the epizoo ...	2011	22107088
[medico-legal assessment of the injuries of fatal victims of building collapse at katowice international fair in katowice/chorzów on january 28, 2006].	on january 28, 2006, during an exhibition of carrier pigeons, the roof of one of the buildings at katowice international fair collapsed. at the time of accident, there were 700 people in the building--65 died and 171 were injured. it was the biggest building disaster in the history of modern poland. the aim of this study was to present the type (character) of the observed injuries, the cause of death of 48 fatal victims and the range of activities and medico-legal examinations performed in the d ...	2015	22117484
adapting the buccal micronucleus cytome assay for use in wild birds: age and sex affect background frequency in pigeons.	micronucleus (mn) formation has been used extensively as a biomarker of damage from genotoxic exposures. the buccal mn cytome (bmcyt) assay provides a noninvasive means of quantifying mn frequency in humans, but it has not been developed for use in wildlife. we adapted the bmcyt assay for use in wild birds, with a focus on feral pigeons (columba livia) as a potential indicator species. five of six urban bird species sampled using oral cavity swabs produced sufficient buccal cells for the bmcyt a ...	2011	22121057
pigeons steer like helicopters and generate down- and upstroke lift during low speed turns.	turning is crucial for animals, particularly during predator-prey interactions and to avoid obstacles. for flying animals, turning consists of changes in (i) flight trajectory, or path of travel, and (ii) body orientation, or 3d angular position. changes in flight trajectory can only be achieved by modulating aerodynamic forces relative to gravity. how birds coordinate aerodynamic force production relative to changes in body orientation during turns is key to understanding the control strategies ...	2011	22123982
genetic diversity of the japanese wood pigeon, columba janthina, endemic to islands of east asia, estimated by newly developed microsatellite markers.	the japanese wood pigeon columba janthina is endemic to islands of east asia and is listed as near threatened by the international union for conservation of nature (iucn). one subspecies, c. janthina nitens, in particular, is at the greatest risk of extinction due to its small population size. to reduce the extinction risk of c. janthina, it is important to understand the species' present genetic status and to develop an appropriate conservation plan based on genetic data. we developed seven new ...	2011	22132786
West nile virus infection of birds, Mexico.	West Nile virus (WNV) has caused disease in humans, equids, and birds at lower frequency in Mexico than in the United States. We hypothesized that the seemingly reduced virulence in Mexico was caused by attenuation of the Tabasco strain from southeastern Mexico, resulting in lower viremia than that caused by the Tecate strain from the more northern location of Baja California. During 2006-2008, we tested this hypothesis in candidate avian amplifying hosts: domestic chickens, rock pigeons, house ...	2011	22172633
clinicopathologic, gross necropsy, and histologic findings after intramuscular injection of carprofen in a pigeon (columba livia) model.	to evaluate the pathologic effects of carprofen in a pigeon model (columba livia), 52 young adult pigeons were used in a randomized control study design. sixteen pigeons were randomly assigned to 1 of 3 treatment groups and received carprofen by intramuscular injection at dosages of either 2, 5, or 10 mg/kg once daily for 7 days. four pigeons served as saline-injected controls. four pigeons from each group and 1 control pigeon were randomly selected on days 2, 4, 6, and 8 to obtain blood samples ...	2011	22216717
eighteen polymorphic microsatellites for domestic pigeon columba livia var. domestica developed by cross species amplification of chicken markers.		2011	22232198
flexural stiffness of feather shafts: geometry rules over material properties.	flight feathers of birds interact with the flow field during flight. they bend and twist under aerodynamic loads. two parameters are mainly responsible for flexibility in feathers: the elastic modulus (young's modulus, e) of the material (keratin) and the geometry of the rachises, more precisely the second moment of area (i). two independent methods were employed to determine young's modulus of feather rachis keratin. moreover, the second moment of area and the bending stiffness of feather shaft ...	2012	22246249
attentional capture? synchronized feedback signals from the isthmi boost retinal signals to higher visual areas.	when a salient object in the visual field captures attention, the neural representation of that object is enhanced at the expense of competing stimuli. how neural activity evoked by a salient stimulus evolves to take precedence over the neural activity evoked by other stimuli is a matter of intensive investigation. here, we describe in pigeons (columba livia) how retinal inputs to the optic tectum (teo, superior colliculus in mammals), triggered by moving stimuli, are selectively relayed on to t ...	2012	22262908