distortion of the gizzard in cyprus pigeons (columba livia) associated with hadjelia truncata infestation.hadjelia truncata is well recognised as an avian parasite but is rarely reported as pathogenic. this paper describes severe disease in pigeons due to this parasite and is the first to describe the condition in cyprus. the morphology of the parasite and the associated lesions are described and illustrated and the pathogenesis of the condition is discussed.19957676581
regional differences along the small intestine of the pigeon (columba livia): histobiochemical evidences.mucosal surface area, protein, dna and rna content, [3h]-thymidine incorporation, total activity of glucosidases, peptidases, phosphatases and transaminases were measured in the duodenum and in the middle and lower parts of the small intestine of the domestic pigeon columba livia. mucosal surface area, protein, nucleic acid content and [3h]-thymidine incorporation were significantly higher in the duodenum and in the middle part of the small intestine than in the lower part. whereas the activitie ...19937691216
tunis virus: a new phlebovirus from argas reflexus hermanni ticks in tunisia.a new phlebovirus provisionally named tunis virus has been isolated from argas reflexus hermanni ticks parasitizing domestic pigeons. it is the first isolation of an arbovirus from tunisia and the fourth tick-borne virus to be isolated from the moghreb following soldado, essaouira and kala iris in morocco. the pathogenic potential of this virus is briefly discussed according to the behaviour of its vector and previous serosurveys in the country.19947726003
isolation of cryptococcus neoformans from pigeon (columba livia) droppings in mexico determine the ecological and epidemiological significance of pigeon excrement in cryptococcosis in mexico city, 251 samples of pigeon droppings were studied. these were collected from houses, public buildings, churches, parks and pigeon nests. each sample was suspended 1:10 in isotonic saline solution and then cultured in staib medium. identification of cryptococcus neoformans was performed based on the development of brown-coloured colonies and the presence of encapsulated yeasts. of 251 sam ...19947746290
hepatic microsomal ethoxyresorufin o-deethylase-inducing potency in ovo and cytosolic ah receptor binding affinity of 2,3,7,8-tetrachlorodibenzo-p-dioxin: comparison of four avian species.the hepatic microsomal ethoxyresorufin o-deethylase (erod)-inducing potency in ovo of 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) was determined in the domestic chicken (gallus gallus), domestic pigeon (columba livia), great blue heron, and double-crested cormorant. dose-response curves were produced by injecting various doses of [3h]tcdd into the air sac of developing eggs during the latter third part of incubation. hepatic erod activities were measured in day-old hatchlings. liver, yolk, and wh ...19957747276
serial learning with a wild card by pigeons (columba livia): effect of list length.pigeons (columba livia) learned 3-, 4- or 5-item lists prior to subset and wild card tests. on the latter, a novel item replaced 1 of the list items. pigeons who learned 3-item lists responded accurately on all subset pairs (ab, bc, and ac) and on all types of 3-item wild card trials (wbc, awc, & abw). pigeons who learned 4- and 5-item lists responded at chance levels of accuracy on all subsets that did not contain a start or an end item (bc, bd, & cd, respectively, on 4- and 5-item subset tests ...19957758291
plasma volume conservation in pigeons: effects of air temperature during dehydration.we assessed the effects of the ambient air temperature prevailing during dehydration, which included complete water and food deprivation, on plasma volume (pv) conservation in pigeons (columba livia) exposed to air temperatures of 25 degrees c (n = 7), 36 degrees c (n = 12), and 40 degrees c (n = 24). the pigeons were dehydrated for 65.4, 32.3, and 27.7 h, on average, at 25, 36, and 40 degrees c, respectively. dehydration rates averaged 5, 10, and 15.2% of initial total body water (tbw) per day ...19947810752
amino acid sequence of the alpha a- and beta-polypeptide chains of the ryukyu rufous turtle dove (streptopelia orientalis stimpsoni) hemoglobin.only one hemoglobin component is recognized in the erythrocytes of the adult ryukyu rufous turtle dove. we have determined the amino acid sequence of the alpha a-globin and the beta-globin by conventional protein sequence analysis. the sequences of both the alpha a- and the beta-globins were highly similar to domestic pigeon hemoglobin. the alpha a-globin has 6 exchanges and beta-globin has 4 exchanges compared with the corresponding domestic pigeon chains.19947811396
diurnal rhythms of plasma corticosterone concentrations in racing pigeons (columba livia domestica) exposed to different light regimens, and the influence of frequent blood sampling.the effects of two different light regimens and the frequency of blood sampling on the diurnal plasma corticosterone concentrations in racing pigeons (columba livia domestica) were investigated. the daily light regimens tested were a period of light during the day (dl; lights on 0515-2215) and shifting of the light period by 12 hours (sl; lights on 1715-1015). in the first experiment, the influence of the frequency of blood sampling was investigated by comparing plasma corticosterone concentrati ...19947832694
sensitivity of the hypothalamic-pituitary-adrenal system of pigeons (columba livia domestica) to suppression by dexamethasone, cortisol, and prednisolone.the sensitivity of the hypothalamic-pituitary-adrenal system in pigeons (columba livia domestica) to glucocorticoid feedback was studied after single intravenous administration of dexamethasone (500, 100, 50, 10, 5, 1, 0.5, and 0.1 micrograms/kg), cortisol (15,000, 3000, 1500, 300, 150, 30, 15, and 3 micrograms/kg), and prednisolone (3500, 700, 350, 70, 35, 7, 3.5, 0.7, and 0.35 micrograms/kg). dose responses, the threshold doses, and the onset of maximum suppression were determined by measuring ...19947832695
salmonella contamination of the environment and its incidence in wild 1984-1991, the incidence of salmonellas was studied in wild birds from various sites in the czech republic. on an agricultural farm with salmonellosis in calves, salmonellae were isolated from eight birds (seven passer domesticus, one serinus serinus) of 31 birds examined. on various agricultural farms with no salmonellosis in farm animals, salmonellae were found in two birds (columba livia f. domestica) of 2186 birds examined. of 35 birds caught at a municipal waste-dump site, salmonellae we ...19947839754
a direct connection between visual wulst and tectum opticum in the pigeon (columba livia) demonstrated by horseradish peroxidase.labelled neurons were observed bilaterally in part of the visual wulst (hyperstriatum accessorium and hyperstriatum intercalatum superior) following unilateral injection of the enzyme horseradish peroxidase into the tectum opticum of pigeons. no labelling was observed in hyperstriatum dorsale. horseradish peroxidase positive fibres running through the tractus septomensencephalicus and ending bilaterally in the tectum opticum were found following injection of the enzyme into hyperstriatum accesso ...19807458532
intratelencephalic projections of the visual wulst in pigeons (columba livia).the visual wulst is the telencephalic target of the thalamofugal visual pathway of birds, and thus the avian equivalent of the striate cortex of mammals. the anterograde tracer phaseolus vulgaris leucoagglutinin was used to follow the intratelencephalic connections of the major constituents of the visual wulst in pigeons. in particular, efferent pathways from the granular layer (intercalated nucleus of the hyperstriatum accessorium, iha), supragranular layer (hyperstriatum accessorium, ha), and ...19957499547
comparative effects of mites and lice on the reproductive success of rock doves (columba livia).we report experimental data comparing the effects of mesostigmatid mites and ischnoceran lice on the reproductive performance of a single group of captive rock doves (columba livia). several components of host reproductive success were compared for the two groups, including number of eggs laid, hatching success, nestling growth rates, fledging success, post-fledging body mass and survival. adult body mass and survival were also compared. there was a dramatic difference in the effects of the mite ...19957885738
extraction of haemoproteus columbae (haemosporina: haemoproteidae) antigen from rock dove pigeons (columba livia) and its use in an antibody elisa.erythrocytic stages of haemoproteus columbae were extracted from the cytoplasm of nucleated red blood cells (rbc) of rock dove pigeons (columba livia) using cationic detergent (n,n',n'-polyoxyethylene(10)-n-tallow-1,3-diaminopropane [edta-20]) and discontinuous percoll gradient density. crude rbc extract (crbce) antigen was prepared. parasitized rbcs were more resistant to edta-20 action than unparasitized cells. an enzyme-linked immunosorbent assay (elisa) was developed for detection of anti-h. ...19947931906
[ethology of the pigeon (columba livia)].an ethometrical analysis of street pigeons showed that most social interactions under conditions of overpopulation are of an aggressive nature. through various mechanisms this frequent aggressive behaviour leads to "slumlike" living conditions characterized by intraspecific stress. it is possible to characterize street pigeons in their urban environment by calculating the frequencies of the most important aggressive and sexually-motivated social interactions. behavioral patterns adapted to their ...19947940514
the nmda-receptor antagonist mk-801 impairs navigational learning in homing pigeons.the present study employed the n-methyl-d-aspartate (nmda) receptor antagonist mk-801 to investigate the possible importance of nmda receptor activation for naturally occurring spatial learning in birds by exploiting the navigational ability of homing pigeons (columba livia). control pigeons released from two unfamiliar release sites displayed vanishing bearings that were poorly oriented. however, when released a second time from the same sites they displayed improved homeward orientation. the c ...19947945145
avian tuberculosis which occurred in an imported pigeon and pathogenicity of the isolates.a tubercular lesion (15 mm in diameter) was found on the skin of the caudal part of the cloaca in a 2-year-old male carrier-pigeon. mycobacterium avium serovar 2 was isolated from the tubercular lesion on the skin and in the feces. the smooth and dome (smd) variant (4.9 x 10(6) cfu) and rough and granular (rg) variant (3.7 x 10(7) cfu) of the isolates were injected into chickens intravenously. the chickens inoculated with the rg variant died on the 39th day and the one with the smd variant died ...19947948399
hippocampal lesions in pigeons (columba livia) disrupt reinforced preexposure but not overshadowing or blocking.three experiments examined the effects of hippocampal lesions in pigeons on overshadowing, blocking, and a latent inhibition treatment (non-differential reinforced preexposure) using a simultaneous visual discrimination paradigm. the results showed that hippocampal damage did not influence overshadowing (experiment 1) or blocking (experiment 2) but did attenuate the retardation in conditioning associated with non-differential reinforced preexposure to to-be-discriminated stimuli (experiment 3). ...19947972889
filariasis (pelecitus sp.) in the cervical subcutaneous tissue of a pigeon with trichomoniasis.filariasis due to pelecitus was found in the subcutaneous tissue of the neck of a domestic pigeon from spain that died from trichomoniasis. macroscopically, filariae were observed in the congested and hemorrhagic cervical connective tissue. microscopically, a particular distribution of parasites with no inflammatory infiltrates was observed. adult nematodes were located in peritracheal connective tissue and in the deep zone of the subcutaneous tissue. microfilariae were mainly located in the sup ...19947980294
[epizootiology and pathogenesis of avian mycobacteriosis in domestic pigeons (columba livia f. domestica)].the occurrence and expansion of avian mycobacteriosis in the pigeon, its sensitivity to infection and epizootological importance as a source of m. avium were investigated. a total of 470 pigeons were examined coming from seven localities with different epizootological situation in avian tuberculosis. tuberculous lesions were found out in 2 birds (0.43%) and mycobacteria were isolated from five birds (1.06%). four out of the five isolated strains of mycobacteria were pathogenic to the domestic fo ...19947992471
neuroactive substances in the developing dorsomedial telencephalon of the pigeon (columba livia): differential distribution and time course of maturation.the avian hippocampal formation has previously been shown to contain many of the same neurotransmitters and related enzymes that are found in mammals. in order to determine whether the relatively delayed development of the mammalian hippocampus is typical of other vertebrates, we investigated the maturation of a variety of neuroactive substances in the hippocampal formation of the homing pigeon. the distribution of two transmitter-related enzymes, choline acetyltransferase (chat) and tyrosine hy ...19947525663
three new recessive behavior mutants in the domestic pigeon.descriptions and breeding tests are reported for three new mutants producing uncoordinated behavior in the domestic pigeon, columba livia. they were discovered by fanciers separately and have been named "erratic," "wobbly," and "crazy." the affected birds can survive and breed in cages, with some difficulty. all have shown simple autosomal recessive inheritance, and at least "erratic" and "crazy" are not alleles. maintenance of the mutants is generally best from matings of heterozygotes. gene sy ...19948024535
memory for pictures of upright and inverted primate faces in humans (homo sapiens), squirrel monkeys (saimiri sciureus), and pigeons (columba livia).humans (homo sapiens) and squirrel monkeys (saimiri sciureus) were tested for memory of upright and inverted primate faces. working memory was tested in experiment 1 with a delayed matching-to-sample procedure, and reference memory was examined in experiment 2 by requiring subjects to learn to discriminate between successive pairs of upright or inverted pictures. both human and monkey subjects showed better working memory for upright than for inverted human faces and better reference memory for ...19948026162
self-control across species (columba livia, homo sapiens, and rattus norvegicus).data from six previous studies of self-control behavior were compared against predictions made by the matching law and by molar maximization. the studies involved pigeons (columba livia), rats (rattus norvegicus), and 3-year-old, 5-year-old, and adult humans (homo sapiens) who had received food as the reinforcer, and adult humans who had received points exchangeable for money as the reinforcer. neither theory proved to be an accurate or better predictor for all groups. in contrast to the predict ...19948026163
transfer of a discrimination by pigeons (columba livia) between pictured locations and the represented experiment 1, pigeons (columba livia) were trained in a successive slide presentation procedure to discriminate between pictures of 2 ends of a room and then trained to find food in the actual room. a congruent-transfer (ct) group learned the spatial discrimination more quickly than an incongruent-transfer (it) group. in experiment 2's replication we used a simultaneous slide presentation procedure and added a control group. the it group required significantly more trials than the ct or contr ...19948026171
connections of the piriform cortex in homing pigeons (columba livia) studied with fast blue and wga-hrp.the piriform cortex in homing pigeons receives a projection from the olfactory bulb and is necessary for the operation of those aspects of the navigational map based on olfactory stimuli in these animals. the afferent and efferent projections of the piriform cortex were studied using retrograde migration of wheat-germ agglutinin horseradish peroxidase (wga-hrp) and fast blue, and anterograde migration of wga-hrp. the piriform cortex was found to receive projections from, and send projections to, ...19948038984
the course and morphology of efferent nerve fibres in the papilla basilaris of the pigeon (columba livia).this paper describes the course and morphology of efferent fibres in an avian cochlea. horseradish peroxidase stained efferent fibres in the pigeon papilla basilaris were identified by nomarski optics and camera lucida drawings. there are at least two types of efferent fibres: large thick fibres take mainly a transversal course and contact short and intermediate hair cells over the free basilar membrane as well as hyaline cells. large efferent fibres contact both hair cells and hyaline cells. sm ...19948040096
distribution of choline acetyltransferase immunoreactivity in the pigeon brain.we have investigated the distribution of cholinergic perikarya and fibers in the brain of the pigeon (columba livia). with this aim, pigeon brain sections were processed immunohistochemically by using an antiserum specific for chicken choline acetyltransferase. our results show cholinergic neurons in the pigeon basal telencephalon, the hypothalamus, the habenula, the pretectum, the midbrain tectum, the dorsal isthmus,the isthmic tegmentum, and the cranial nerve motor nuclei. cholinergic fibers w ...19948040363
ectoparasite virulence is linked to mode of transmission.theory suggests that the evolution of parasite virulence is linked to the dynamics of parasite transmission. all else being equal, parasites transmitted vertically from parents to offspring should be less virulent than parasites capable of horizontal transmission to unrelated hosts. this is because the fitness of vertically transmitted parasites is tightly linked to the reproductive success of the host, whereas the fitness of horizontally transmitted parasites is relatively independent of host r ...19948058799
administration of total parenteral nutrition in pigeons.venous access devices connected to jugular vein catheters were implanted sc in 2 groups of 6 white carneau pigeons (columba livia). total parenteral nutrition (tpn), or a control solution (lactated ringer's solution) was infused as a bolus 4 times daily. physiologic, hematologic, and biochemical variables were monitored over 5 days. complications in the tpn-treated pigeons included 8.7% weight loss during the 5-day trial, hyperglycemia for up to 90 minutes after infusion, and glucosuria after in ...19948067614
feeding rhythms in constant light and constant darkness: the role of the eyes and the effect of melatonin infusion.exposure to constant light abolishes circadian behavioral rhythms of locomotion and feeding as well as circulating melatonin rhythms in pigeons (columba livia). to determine if feeding rhythmicity could be maintained in pigeons exposed to constant light, periodic infusions; (10 h/day) of melatonin were administered to pinealectomized and bilaterally retinectomized/pinealectomized pigeons under conditions of both constant darkness and constant light. the infusions were sufficient to entrain rhyth ...19948083848
visual and somatosensory inputs to the avian song system via nucleus uvaeformis (uva) and a comparison with the projections of a similar thalamic nucleus in a nonsongbird, columba livia.nucleus uvaeformis (uva), previously identified as a component of song control circuitry in songbirds, and nucleus dorsolateralis posterior thalami, pars caudalis (dlpc) in pigeon, were compared with respect to their relative positions in the dorsolateral part of the posterior thalamus, their cell types, and their afferent and efferent projections. both nuclei are closely related to the habenulointerpeduncular tract, have similar cell types, and receive a dense projection from deep layers of the ...19947860787
nucleus of the solitary tract and dorsal motor nucleus of the vagus nerve of the pigeon: localization of peptide and 5-hydroxytryptamine immunoreactive fibers.the distribution of peptide and serotonin fibers in the nucleus of the solitary tract (nts) and the dorsal motor nucleus of the vagus nerve (dmnx) in the pigeon (columba livia) was investigated immunocytochemically. this information was correlated with the viscerotopic organization of the nuclei and with central nts circuitry to suggest the role of the neurochemical containing fibers in the regulation of organ function. the distribution of fibers containing cholecystokinin (cck), calcitonin gene ...19938132859
an unusual outbreak of streptococcus bovis septicaemia in racing pigeons (columba livia).in december 1991, an outbreak of streptococcus bovis septicaemia occurred in a belgian pigeon loft where 25 male and 25 female racing pigeons were housed. the main clinical signs included inability to fly and poor breeding results. none of the female pigeons and only one male pigeon was able to fly. nine affected pigeons were necropsied. histologically a tenosynovitis of the tendon of the deep pectoral muscle was observed in most of them and s bovis was isolated from the canalis triosseus or the ...19948135007
vitread proliferation of filamentous processes in avian müller cells and its putative functional order to examine to what extent the neuronal and metabolic activities of avascular vertebrate retinae are reflected in the morphology of their müller cells we have studied (by using several monoclonal antibodies) the morphology of müller cells in two species of diurnal birds (chicken, gallus domesticus, and pigeon, columba livia) and one species of nocturnal saltwater crocodiles (crocodylus porosi). in all three species, the outer nuclear layer is relatively thin and the müller cell trunks di ...19947860802
jaw muscle (emg) activity and amplitude scaling of jaw movements during eating in pigeon (columba livia)during each phase of the pigeon's eating sequence, jaw opening amplitude (gape) is adjusted to the size of the food object; first prior to contact (grasping), again in positioning the food (stationing), and finally, during its movement through the oral cavity (intraoral transport). part i of this study examined jaw movement kinematics during ingestion of different size food pellets to determine the relative contribution of velocity and rise time variables. part ii specified the muscle activity p ...19948182561
drinking behavior and jaw muscle (emg) activity in the pigeon (columba livia).the relation between jaw movements and jaw muscle activity was examined during two different types of drinking in pigeons: "tip" and "rictus" drinking. the amplitude and duration of jaw opening is greater for "rictus" than for "tip" drinking, but both types involve individual cycles of jaw-opening and closing movements, organized into bouts. cycle duration increases gradually over the initial portion of the bout and is relatively constant thereafter. each drinking cycle is composed of an initial ...19948182562
oral and dermal toxicity of organophosphate pesticides in the domestic pigeon (columba livia). 19948186631
structural and functional divergences of the columbid annexin i-encoding cp37 and cp35 genes.annexin-i proteins in the pigeon are encoded by two genes. one encodes a constitutively expressed cp37 protein, and the other encodes a major prolactin (prl)-regulated protein (cp35). as one goal in understanding the differential regulation of these genes, we have determined a 10.8-kb genomic sequence of the cp37 gene containing 1.3 kb of 5'-flanking region and the first six exons. the promoters of cp37 and cp35 are 84% identical over the first 210 bp upstream from the transcription start point ...19948206371
the visual acuity for the lateral visual field of the pigeon (columba livia).previous studies on pigeons indicated that the visual acuity for the frontal visual field was much higher than that for the lateral one. suspecting that the poor values for the lateral field were due to suboptimal testing conditions, we determined the lateral field acuity in eight head-fixed pigeons with high-contrast square-wave gratings. an instrumental conditioning task with water as reinforcer and mandibulation as an operant was used. subjects achieved a mean acuity value of 12.6 c/deg. the ...19938236853
connections of the auditory forebrain in the pigeon (columba livia).ascending auditory efferents in birds terminate mainly within field l2, a cytoarchitectonically distinct region of the caudomedial telencephalon. the organization of field l2, and that of its flanking regions, l1 and l3, was investigated with 14c-2-deoxyglucose (14c-2-dg), cytochrome oxidase, and both retrograde and anterograde tracing techniques. field l2 was found to contain a high concentration of cytochrome oxidase. following auditory stimulation, 14c-2-dg autoradiography revealed that field ...19938276991
visual acuity and hemispheric asymmetries in pigeons.pigeons and domestic chicks tested under monocular conditions in pattern distinction tasks generally show higher discrimination performances with the right eye seeing. at least two different mechanisms could mediate this asymmetry: the dominance of the right eye could either be due to hemispheric differences in the cognitive operations performed during these tasks, or may reflect a lateralization in the spatial frequency discrimination capacity of the left and the right eye system. the aim of th ...19948003246
roles of adrenal and gonadal steroids and season in uropygial gland function in male pigeons, columba gauge the relative regulative roles of adrenal, gonadal, and thyroid hormones on uropygial gland of male adult pigeons, morphometric, histological, and histochemical observations have been made on a seasonal basis in normal as well as experimentally manipulated birds. normal birds showed a parallel adrenal-gonadal-uropygial relationship and inverse adrenal-thyroid, thyroid-gonadal, and thyroid-uropygial relationships. induced hypocorticalism by dexamethasone in the breeding season and hyperco ...19938282171
food deprivation- vs. intraventricular adrenaline-induced feeding and postprandial behaviors in the pigeon (columba livia).the present study was designed to investigate possible similarities between the feeding and postprandial behavioral profile observed after different periods of food deprivation and after intracerebroventricular (icv) injections of adrenaline (a) (30 nmol/microliter) in satiated pigeons (columba livia). the results indicate that the postprandial sleep-like behavior increases observed after a treatment are similar only to those observed after prolonged periods of fasting. these parallel behavioral ...19938295943
the visual response properties of neurons in the nucleus of the basal optic root of the northern saw-whet owl (aegolius acadicus).the nucleus of the basal optic root (nbor) in birds is a component of the accessory optic system (aos) which is involved in the analysis of visual flowfields normally resulting from self-motion. using standard extracellular techniques, we recorded from 81 single-unit and multi-unit clusters in the nbor of the northern saw-whet owl, aegolius acadicus, an avian species that has a visual system with frontal emphasis. these cells responded best to large patterns of random dots moving either upward ( ...19948306188
[peliás, columba livia, the rock pigeons, as nomenclature]. 19938333009
whole-body exposures to a phosphoric acids aerosol: ii. food/water/weight effects in wild rodent and avian species.separate inhalation-chamber studies were conducted to assess acute/subacute food intake (g), water intake (ml), and body weight (g) effects of four whole-body phosphoric-acids-aerosol exposures in black-tailed prairie dogs (cynomys ludovicianus); subacute effects of two exposures were studied in rock doves (columba livia). a 95% red phosphorus/5% butyl rubber (rp/br) mixture was burned to produce the aerosol. each study involved (1) 3 rp/br target concentration groups (0.0, 1.0, and 4.0 mg/l), ( ...19938345534
pharmacokinetics and anthelmintic efficacy of febantel in the racing pigeon (columba livia).this paper reports on the pharmacokinetics and the efficacy of febantel against capillaria obsignata and ascaridia columbae in the racing pigeon. febantel was rapidly cleared from the circulation and highly metabolized. the efficacy of febantel against capillaria and ascaridia was studied on lightly and heavily infected pigeons. the efficacy against ascaridia was 100% for the faecal egg count reduction (fecr) as well as for the worm reduction in all treated pigeons. after two treatments with feb ...19938345572
potassium currents in mammalian and avian isolated type i semicircular canal hair cells.1. type i vestibular hair cells were isolated from the cristae ampullares of the semicircular canals of the mongolian gerbil (meriones unguiculatus) and the white king pigeon (columba livia). dissociated type i cells were distinguished from type ii hair cells by their neck to plate ratio (npr) and their characteristic amphora shape. 2. the membrane properties of gerbil and pigeon type i hair cells were studied in whole-cell voltage- and current-clamp using the perforated patch technique with amp ...19948158233
variations of glycolytic kinases and pentose-phosphate pathway dehydrogenases in response to lead accumulation in hemopoietic cells of rock doves (columba livia). 19938387841
stimulatory effects on lactotrophs and crop-sac of interleukin-1 and interleukin-2 in pigeons (columba livia).the ultrastructural effects of human-recombinant interleukin-1 beta (il-1 beta) and human-recombinant interleukin-2 (il-2) on the crop-sac (the target organ for prolactin secretion in birds) and the anterior pituitary lactotrophs, were studied in pigeons (columba livia). the intraventricular microinfusion of the two interleukins produced maximal crop-sac stimulation with milk-like secretion, as demonstrated by the observation of ultrastructural changes in the lactiferous areas through scanning a ...19938406140
the object-line inferiority effect in pigeons.eight pigeons (columba livia) were trained to discriminate between diagonal lines presented alone or embedded in a redundant l-shape right-angle form. the stimuli were white and were presented in an environment that was otherwise totally dark. numerous experiments done with human observers have shown a strong superiority effect when the diagonal lines are embedded in redundant contexts. however, in experiment 1 of the present study, the pigeons discriminated significantly better between the two ...19938433900
discrimination of duration ratios by pigeons (columba livia) and humans (homo sapiens).humans (homo sapiens) were trained on 2 versions of a 2-alternative, forced-choice procedure. first, subjects judged which of 2 successive stimulus durations was longer. second, subjects judged whether the ratio of the 2 durations was less or greater than a criterion ratio (e.g., 2:1). accuracy was significantly lower for the task in which the judgment was made according to the ratio of the 2 durations. this result is different than that obtained by fetterman, dreyfus, and stubbs (1989), who tra ...19938444016
photocurrents in retinal rods of pigeons (columba livia): kinetics and spectral sensitivity.1. membrane photocurrents were recorded from outer segments of isolated retinal rods of pigeons (columba livia), the first such measurements on the photoreceptors of a bird. the amplitude of the response to 20 ms flashes of narrow wavelength bands of light increases linearly with intensity at low photon fluxes and saturates at higher intensities. the maximum (saturating) photocurrent observed in forty-nine rod cells was 50 pa. larger responses with less variability in the intensity for half-maxi ...19938120835
an experimental test of the site specificity of preening to control lice in feral specificities of ectoparasites on the host may have evolved due to the selective pressure exerted by host grooming. the present study demonstrates that the efficiency of avian preening varies among sites on the host. the study relies on the simple idea that the effectiveness of preening behavior to control lice can be quantified by the removal rate of dead lice glued onto the feathers of living birds. two treatments were done to document site-specific differences in the efficiency of preeni ...19938277395
whole body exposures to a phosphoric acids aerosol: i. spontaneous activity effects in wild rodent and avian species.two inhalation-chamber studies were conducted to assess acute (2-h out-of-chamber) and subacute (< or = 6 d postexposure) spontaneous activity effects of whole-body phosphoric acids aerosol exposure(s) in black-tailed prairie dogs (cynomys ludovicianus) and rock doves (columba livia). the aerosol was generated using a red phosphorus/butyl rubber (rp/br) mixture under development as a military obscurant. each study involved (1) 3 rp/br target concentration groups [0.0 (controls), 1.0, and 4.0 mg/ ...19938501771
antibody prevalence and isolation of chlamydia psittaci from pigeons (columba livia).the isolation of chlamydia psittaci and serological detection of chlamydia-specific antibodies in racing pigeons and pigeons from public parks is described. several serological methods (complement fixation test, indirect microimmunofluorescence test, and enzyme-linked immunosorbent assay) were compared with bacteriological techniques (isolation both in embryonated eggs and mccoy cell monolayers). tests confirmed that 28.6%, 33.5%, and 35.9% of the pigeons, respectively, were seropositive by the ...19938363515
immunohistochemical characteristics of cutaneous herbst corpuscles from beak and rictus in domestic pigeon.herbst corpuscles are the avian equivalent to the mammalian pacinian corpuscles. in this study we used indirect peroxidase-anti peroxidase (pap) immunohistochemistry to analyze the distribution in the pigeon cutaneous herbst corpuscles, of several markers which are known to specifically label the axon, the schwann-related and perineurial-related cells in pacinian corpuscles. the distribution of the assessed antigens on herbst corpuscles was as follows: i) the central axon displayed positive immu ...19958534581
present state of research on house dust mites (pyroglyphidae) in the czech republic.systematic research on house dust mites in the czech republic started in the early seventies, when mite fauna of human dwellings and distribution of pyroglyphid mites were studied. special attention was paid to old-age-pensioners' homes and children's sanatoria. pyroglyphidae were found also in the city air and in the dust of city pavements, especially in localities with high occurrence of domestic pigeons. while d. pteronyssinus and d. farinae mostly occurred in permanently inhabited flats, eur ...19958553663
[tick-transmitted arbovirus in maghreb].the problem of arbovirus infections in maghreb has been relatively neglected in the pst in spite of a rich diversity of biotopes, the presence of potential reservoirs and vectors, and their position on the flight path of the palearctic-african bird migration systems, western branch. moreover, west nile virus has been isolated from southern algeria since 1968. from 1979 to 1989, ticks were collected from wild birds, pigeons, bats, rodents, poultry, camels, wild boars, domestic mammals and man, an ...19958555772
serum levels of prolactin and alpha-melanotrophin and structure of the ovary during the reproductive cycle of columba livia (domestic pigeon).given the importance of the hormones prolactin and alpha-melanotrophin in the regulation of the mammalian reproductive cycle, it was decided to assess their serum levels during the reproductive cycle of columba livia (domestic pigeon). female pigeons were utilized in the stages of egg-laying, incubation and rearing. simultaneously, the structural changes of the ovary in the aforementioned periods were studied. the levels of prolactin and alpha-melanotrophin showed similar behaviour. the low conc ...19948560068
anatomical evidence of a retino-thalamo-hippocampal pathway in the pigeon (columba livia).the aim of the present study was to demonstrate the existence of a retino-thalamo-hippocampal pathway in the pigeon and, more specifically, to identify its thalamic relay (n. superficialis parvocellularis: spc). fluorescence axonal tracing techniques were used combining the orthograde axonal transport of ritc after its intraocular injection and the retrograde axonal transport of various other fluorescent tracers (fb, fg, eb) injected into the hippocampal complex. since the n.spc has also been sh ...19958568219
borrelia in pigeons: no serological evidence of borrelia burgdorferi order to clarify the supposed involvement of urban pigeons (columba livia livia) in the epidemiology of lyme disease, the presence of antibodies against borrelia burgdorferi and borrelia anserina in pigeons' sera, collected in 12 areas of northern and central italy, was evaluated. this evaluation was carried out using a classic immunofluorescence assay (ifa), a surface immunofluorescence assay (sifa) and a standard western blot (wb) assay. a total of 104 out of 3,186 (3.26%) serum samples wer ...19958578924
visual search for natural grains in pigeons (columba livia): search images and selective attention.the experiments reported here were designed to test the suggestion of many researchers that selective attention to visual features of a prey can account for search-image effects. in 3 experiments pigeons ate wheat and vetch grains presented on multicolored and gray gravel trays. in experiment 1 search-image effects were evident when grains were cryptic but not when they were conspicuous. experiment 2 demonstrated that search images can be activated when the grains encountered are either cryptic ...19968618099
search images: selective attention to specific visual features of 3 experiments, pigeons (columba livia) searched a digitized image of a gravel patch on a computer monitor for cryptic grains. experiment 1 demonstrated that the bird's ability to detect a type of grain improved over successive encounters, and detection of alternative targets was attenuated when a search image was active. experiment 2 demonstrated search-image effects independently for the 2 grains. perception was biased to detect wheat grains after wheat encounters and was biased to detect be ...19968618100
operant discrimination learning in detelencephalated pigeons (columba livia).operant discrimination learning was analyzed in pigeons after massive telencephalic lesions. twenty-one pigeons were divided into three groups: non-lesioned (n = 6), sham-lesioned (n = 5) and telencephalon lesioned (n = 10). lesion surgeries were carried out before any experimental training. learning procedures were run in the same sequence for all groups and under a food deprivation of 80% of the ad libitum weight. successive discrimination was programmed by the alteration of red and yellow lig ...19958634682
centrifugal projections upon the retina: an anterograde tracing study in the pigeon (columba livia).previous work has shown that the avian retina receives two types of centrifugal fibers from the brain. these types can be distinguished based on the size and the morphology of their terminal endings and have been termed convergent and divergent. the centrifugal fibers arise from the isthmooptic nucleus (ion) and the surrounding ectopic cell region (ecr). we used injections of anterograde tracers either to the ion/ecr or to the ecr only to determine the morphology, depth of termination, and regio ...19958636463
[the morphofunctional characteristics of the interstitial endocrinocytes (leydig cells) of the testes in vertebrates under conditions of seasonal change in reproductive activity].by means of light and electron microscopy the structural organization of leydig cells was studied in rana ridibunda, lacerta agilis, columba livia in the periods of reproductive activity and reproductive break. the dynamics of structural changes of some parameters of the testicles (interstitial tissue square, endocrinocytes number, state of the cytoplasm, structural components and the volume of nuclei) was shown in the process of the reproductive activity seasonal changes. nuclear volume and the ...19958688941
central projections and somatotopic organisation of trigeminal primary afferents in pigeon (columba livia).injections of cholera toxin b-chain conjugated to horseradish peroxidase into individual peripheral branches of the trigeminal nerve or into the trigeminal ganglion showed that an ascending trigeminal tract (tta) terminated in distinct ventral and dorsal divisions of the principal sensory nucleus (prvv and prvd, respectively), and a descending tract (ttd) terminated within pars oralis, pars interpolaris, and pars caudalis divisions of the nucleus of ttd (nttd) and within the dorsal horn of the f ...19968725298
projection of the nucleus pretectalis to a retinorecipient tectal layer in the pigeon (columba livia).the avian optic tectum is composed of at least 15 separate laminae that are distinguishable on the basis of their morphological features and patterns of afferent and efferent connectivity. layer 5b, a major retinorecipient layer, exhibits dense, dust-like, neuropeptide y-positive (npy+) immunoreactive labeling, whereas sparse, larger caliber npy+ fibers are found in laminae 4 and 7. anterograde and retrograde labeling techniques, immunohistochemistry, and retinal lesion studies were used to dete ...19968725349
measurement of circadian rhythms of ocular melatonin in the pigeon by in vivo microdialysis.ocular melatonin rhythms were measured in pigeons (columba livia) by in vivo microdialysis. the birds were placed in light-dark cycles with 12 h of light and 12 h of darkness (ld12:12) or continuous dim light (lldim) after ld12:12. under ld12:12, melatonin levels were low during the light and high during the dark. the rhythms persisted under lldim with lower levels during the subjective day and higher levels during the subjective night. two hours of light exposure in the middle of the night acut ...19958742471
responsiveness of the glucocorticoid-suppressed pituitary-adrenocortical system of pigeons (columba livia domestica) to stimulation with arginine vasopressin.this paper reports on the duration of the suppressive effects of single high and low doses of dexamethasone, cortisol, and prednisolone on the pituitary-adrenocortical (pa) system in pigeons. in addition, the effects of long-term daily administration of a high dose of dexamethasone are reported. in expt. 1, low and high doses of dexamethasone (0.5 microgram/kg and 0.5 mg/kg), cortisol (15 micrograms/kg and 1.5 mg/kg), and prednisolone (3.5 micrograms/kg and 3.5 mg/kg) were administered around th ...19968790880
no evidence for diurnal variation in the responsiveness of the pituitary-adrenocortical axis of the pigeon (columba livia domestica) to stimulation with adrenocorticotrophin and vasopressin.the responsiveness of the pituitary-adrenocortical axis of the pigeon (columba livia domestica) to intravenous administration of high and low doses of adrenocorticotrophic hormone (acth) and following arginine vasopressin (avp) was investigated at two different moments of the diurnal rhythm. administrations of acth and avp were performed at the moment of low plasma corticosterone concentration and during high plasma corticosterone concentration. plasma corticosterone concentrations following adm ...19968790898
effect of subchronic and chronic exposure to 5-hydroxytryptophan (5-htp) on the aggressive behavior induced by food competition in undernourished dominant and submissive pigeons (columba livia).the acute administration of 5-htp was reported to block in undernourished dominant pigeons the aggressive attacks induced in a submissive partner by food competition. in the present study, undernourished pigeons with previously consolidated dominance were submitted to subchronic and chronic 5-htp treatment. adult males (n = 28) were kept at 80% of their body weight by a restricted diet. these were divided in pairs made of a previously ranked dominant subject (total time spent in aggression highe ...19968800647
effect of the i.c.v. injection of 5,7-di-hydroxytryptamine on the aggressive behavior of dominant and submissive pigeons (columba livia).the acute and chronic treatment with 5-htp was reported to block the aggressive reaction induced by food competition in undernourished dominant pigeons. such treatment was not effective, however, in submissive pigeons. in this report we describe the effect of the neurotoxine 5, 7-dht on aggression, defense, emotion, feeder control, and other behaviors in dominant and submissive male pigeons maintained at 80% of their normal weight. these were ranked through daily food competition trials. to obta ...19968801602
in ovo 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure in three avian species. 1. effects on thyroid hormones and growth during the perinatal period.thyroid hormones are important in the perinatal growth and development of avian species, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) and related compounds have been shown to cause alterations in these hormones in laboratory animals. since the decreased reproductive success in certain fish-eating bird populations exposed to tcdd and related compounds is characterized by high embryo and hatchling mortality, we examined the effects of in ovo tcdd exposure on plasma thyroid hormone concentrations ...19968806844
in ovo 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure in three avian species. 2. effects on estrogen receptor and plasma sex steroid hormones during the perinatal opposed to mammals, the heterogametic sex in birds is female, and sexual differentiation of the central nervous system away from the intrinsic male pattern is dependent on ovarian estrogen secretions during the perinatal period. the contamination of aquatic systems with 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) and related compounds has been suggested to be responsible for decreased reproductive success in certain wild fish-eating bird populations. since tcdd has been shown to alter estrogen ...19968806845
effects of ablation of the presumed equivalent of the mammalian prefrontal cortex on pigeon homing.pigeons (columba livia) with bilateral ablation of the postero-dorsolateral neostriatum and the overlying corticoid were compared with unoperated control subjects in homing from both familiar and unfamiliar sites. before the operation all the pigeons were subjected to 8 training flights from a site destined to be the familiar one. postoperatively, the groups did not differ in orientation from the familiar site. in their releases from unfamiliar sites, however, the operated birds oriented in the ...19938484893
the relative importance of location and feature cues for homing pigeon (columba livia) goal recognition.homing pigeons were raised and trained in two lofts that differed with respect to their color features and location in space. during training, pigeons displayed accurate site preference for a particular loft. when tested for loft preference with the feature cues switched between the 2 lofts, the pigeons returned to the loft that occupied the correct location. in a 2nd experiment, pigeons were trained to find food hidden in 1 of 4 color bowls (feature cues) located next to a landmark beacon (prox ...19968851555
transmission of antibodies to chlamydia psittaci and coxiella burnetii through eggs and "crop milk" in pigeons.young semi-domesticated pigeons captured or hatched from eggs gathered in bratislava during 1989-1991 were examined for complement fixing antibodies to chlamydia psittaci and agglutinating antibodies to coxiella burnetii. antibodies to ch. psittaci were present in 76% of birds younger than 24 h, in 47.7% between 1 and 10 days of age and in 12% of nestlings over 10 days old. antibodies to ch. psittaci were also detected in "crop milk" of 4.1% of 1 to 10 day old birds and in 4.5% of specimens olde ...19938519359
distribution of serotonin-immunoreactivity in the brain of the pigeon (columba livia).the distribution of serotonin (5-ht)-containing perikarya, fibers and terminals in the brain of the pigeon (columba livia) was investigated, using immunohistochemical and immunofluorescence methods combined with retrograde axonal transport. twenty-one different groups of 5-ht immunoreactive (ir) cells were identified, 2 of which were localized at the hypothalamic level (periventricular organ, infundibular recess) and 19 at the tegmental-mesencephalic and rhombencephalic levels. ten of the cell g ...19968881471
the muscarinic acetylcholine antagonist scopolamine impairs short-distance homing pigeon navigation.the present study employed intramuscular (i.m.) injections of the acetylcholine (ach) receptor antagonist scopolamine hydrobromide (0.10 mg/kg) to investigate the possible involvement of ach in naturally occurring spatial navigation in homing pigeons (columba livia). control pigeons receiving injections of saline or scopolamine methylbromide, an ach antagonist that does not cross the blood-brain barrier, were oriented in a homeward direction when released from a location 8 km from home. in contr ...19968884933
lateral hyperstriatal lesions disrupt simultaneous but not successive conditional discrimination learning of pigeons (columba livia).in 2 experiments we explored the effects of lateral versus medial laminar lesions of the hyperstriatum in pigeons (columba livia); medical lesions were largely confined to the hyperstriatum accessorium, and lateral lesions to the hyperstriatum dorsale and hyperstriatum ventrale. in experiment 1, lateral, but not medial, lesions disrupted acquisition of a simultaneous conditional discrimination; both medial and lateral lesions disrupted reversal of the discrimination. the reversal deficits of the ...19938484894
excitatory and inhibitory neurotransmitters in the nucleus rotundus of pigeons.rotundal neurons in pigeons (columba livia) were examined for the effects of glutamate and its agonists nmda and ampa, antagonists cpp and cnqx, as well as of gaba and its antagonist bicuculline, on visual and tectal stimulation-evoked responses. glutamate applied by iontophoresis excited all 48 rotundal cells tested, and this excitation was blocked by cnqx but not by cpp in 98% of cases, with 2% of cells being blocked by either cnqx or cpp. out of 21 cells excited by ampa, 20 were also excited ...19958924406
visually elicited head rotation in pigeons (columba livia).horizontal rotational head movements were video-taped from pigeons standing freely in a rotating cylinder. the cylinder carried vertically striped patterns approximating a sinusoidally modulated horizontal intensity distribution. we altered systematically various stimulus parameters: spatial wavelength and contrast of the pattern, angular velocity of the pattern motion and mode of motion onset. we found: (1) both gradual acceleration of the patterned cylinder as well as immediate onset of patter ...19968944291
age-related changes in the medullary reticular epithelial cells of the pigeon bursa of fabricius.the medulla of the avian bursal lymphoid follicles contains heterogeneous cell populations, including the so-called medullary reticular epithelial cells (rec). these cells may contribute to the bursal microenvironment for b-lymphocyte differentiation and maturation. the bursa of fabricius undergoes well-characterized posthatching developmental changes, but the age-related changes of the medullary rec have not been studied. the present study approaches this topic by analyzing hallmarks of epithel ...19968955787
[mallophaga of pigeons in cracow].infestation of columba livia domestica gmelin with mallophaga has been investigated in both, breeding and feral pigeons. all pigeons came from the area of cracow. five species of mallophaga have been distinguished: columbicola columbae columbae (l.), campanulotes bidentatus compar (burm.), coloceras damicornis fahrenholzi eichler, hohorstiella gigantea lata (piag.), neocolpocephalum (neocolpocephalum) turbinatum (denny). it appeared that the first two of the above-mentioned species showed the hi ...19968967083
[ultrastructural surface properties in columbicola columbae s. str. (esthiopteridae, mallophaga-ischnocera) from domestic pigeons].all post-embryonal stages of columbicola columbae columbae (l.), the common parasite of pigeon, were investigated with regard to morphology, particularly surface ultrastructures. many qualitative characters differing c. columbae s. str. from the investigated up to now species of mallophaga were found in sem. they are among others double lateral protuberances of head (clavus and clavulus) as well as parallel sculpture of pore organs on the last two segments of antennae. the structures showed at t ...19968967084
nocturnal digestion, cloacal excretion, and digestion-related thermogenesis in pigeons (columba livia).two indicators of nocturnal digestive activity were identified in pigeons. experiment 1 showed that a sizable amount of food empties from the crop while pigeons are inactive during the night. experiment 2 showed that the number and volume of cloacal droppings during the night were directly related to the volume of food consumed during the day. the temporal pattern of cloacal droppings in the night was systematically related to features of the nocturnal body temperature (tb) curves, suggesting th ...19978976537
molecular characterization of the pigeon p-opsin gene.the chicken gene encoding pineal gland-specific opsin (p-opsin) has been previously characterized. we report here the orthologous pigeon (columba livia) p-opsin gene. the deduced pigeon p-opsin lacks a potential n-glycosylation site in the n-terminus, but has multiple phosphorylation sites in the c-terminus, which are opposite from the characteristics of the chicken p-opsin.19968982090
pigeons do not complete partly occluded of the most common obstacles to object perception is the fact that objects often occlude parts of themselves and parts of other objects. perceptual completion has been studied extensively in humans, and researchers have shown that humans do complete partly occluded objects. in an effort to understand more about the mechanisms underlying completion, recent research has extended the study of perceptual completion to other mammalian species. monkeys and mice also seem to complete two-dimensiona ...19968983050
projections of the dorsomedial nucleus of the intercollicular complex (dm) in relation to respiratory-vocal nuclei in the brainstem of pigeon (columba livia) and zebra finch (taeniopygia guttata).injections of neuronal tracers were made into the dorsomedial nucleus of the intercollicular complex (dm) of pigeons and zebra finches in order to investigate the projections of this nucleus which has long been implicated in respiratory-vocal control. despite the fact that pigeons are nonsongbirds and zebra finches are songbirds, the projections were very similar in both species. most descended throughout the brainstem, taking ventral and dorsal trajectories, which merged in the medulla. those d ...19978989654
pharmacokinetics and anti-trichomonal efficacy of a dimetridazole tablet and water-soluble powder in homing pigeons (columba livia).the anti-trichomonal efficacy and pharmacokinetics of dimetridazole were investigated in the homing pigeon (columba livia). dimetridazole was formulated for drinking water medication and as a prolonged-release tablet. to suppress a trichomonas gallinae infection successfully, medicated drinking water containing dimetridazole (400 mg/l) had to be administered for at least 3 days. a two-day treatment with a dimetridazole tablet (20 mg/tablet) in fasted, as well as in fed, pigeons was shown to be i ...19968992028
capacity of birds for transitive inference: the solution of the gillan test by corvids and pigeons.a system of four to five differentiations forming a series, in which the magnitude of the reinforcement (r) of each succeeding color stimulus was greater than the preceding by one unit, was formed in pigeons (columba livia l.) and crows (corvus corone cornix l.). the number of units of the r that was associated with each of the stimuli increased successively from stimulus pair to stimulus pair from one up to four to five (1st series) and from five to ten (2nd series). after the development of th ...19969000218
mnemonics for variability: remembering food delay.three experiments with white carneaux pigeons (columba livia) investigated memory and decision processes under fixed and variable reinforcement intervals. response rate was measured during the unreinforced trials in the discrete-trial peak procedure in which reinforced trials were mixed with long unreinforced trials. two decision models differing in assumptions about memory constraints are reviewed. in the complete-memory model (j. gibbon, r.m. church, s. fairhurst, & a. kacelnik, 1988), all int ...19979008863
transcription of lampbrush chromosomes of a centromerically localized highly repeated dna in pigeon (columba) relates to sequence arrangement.a highly repetitive, centromerically localized dna sequence (pr1) has been isolated from the genomic dna of two species of pigeon (columba livia and c. palumbus). pr1 is approximately 900 bp long. it includes a sequence that is similar to the cenp-b box of mammals. it represents about 5% of the genome in c. livia and 2% in c. palumbus. in both species, tandem arrays of pr1 form part of larger repeating units. the organization of pr1 repeats and the larger repeating units is strikingly different ...19969024976
distribution and connections of inspiratory premotor neurons in the brainstem of the pigeon (columba livia).we have recorded extracellular, inspiratory-related (ir) unit activity in the medulla at locations corresponding to those of neurons retrogradely labeled by injections of retrograde tracers in the lower brachial and upper thoracic spinal cord, injections that covered cell bodies and dendrites of motoneurons innervating inspiratory muscles. bulbospinal neurons were distributed throughout the dorsomedial and ventrolateral medulla, from the spinomedullary junction through about 0.8 mm rostral to th ...19979067829
existence of parvalbumin and biochemical characterization in quail and pigeon skeletal muscles with different fiber type compositions.the localization of parvalbumin was determined in skeletal muscles with different fiber type compositions from quails (coturnix japonica) and pigeons (columba livia) by sandwich elisa. the biochemical profiles of these muscles were evaluated by the assay of total lactate dehydrogenase (ldh) activity as well as the ldh isozymes for anaerobic metabolism, and by the analysis of myoglobin for aerobic metabolism. the quail fast posterior latissimus dorsi (pld) with a lower myoglobin content and highe ...19979097460
development of the retinotectal system in the pigeon: a cytoarchitectonic and tracing study with cholera toxin.the optic tectum of the pigeon (columba livia) is marked by morphological dorso-ventral and left-right differences. both features seem to be related to functional specializations, but the responsible developmental mechanisms are unclear. since the visual system becomes functional only after hatching, the developmental processes might be extended into the post-hatching period. the development of the asymmetries in the tectofugal system, however, depends on an asymmetric light stimulation acting a ...19979193729
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