Captive Pigeons Research Articles

Genetic diversity of Cryptosporidium spp., Encephalitozoon spp. and Enterocytozoon bieneusi in feral and captive pigeons in Central Europe.

Cryptosporidium spp., Enterocytozoon bieneusi and Encephalitozoon spp. are the most common protistan parasites of vertebrates. The results show that pigeon populations in Central Europe are parasitised by different species of Cryptosporidium and genotypes of microsporidia of the genera Enterocytozoon and Encephalitozoon. A total of 634 and 306 faecal samples of captive and feral pigeons (Columba livia f. domestica) from 44 locations in the Czech Republic, Slovakia and Poland were analysed for the presence of parasites by microscopy and PCR/sequence analysis of small subunit ribosomal RNA (18S rDNA), 60kDa glycoprotein (gp60) and internal transcribed spacer (ITS) of SSU rDNA. Phylogenetic analyses revealed the presence of C. meleagridis, C. baileyi, C. parvum, C. andersoni, C. muris, C. galli and C. ornithophilus, E. hellem genotype 1A and 2B, E. cuniculi genotype I and II and E. bieneusi genotype Peru 6, CHN-F1, D, Peru 8, Type IV, ZY37, E, CHN4, SCF2 and WR4. Captive pigeons were significantly more frequently parasitised with screened parasite than feral pigeons. Cryptosporidium meleagridis IIIa and a new subtype IIIl have been described, the oocysts of which are not infectious to immunodeficient mice, whereas chickens are susceptible. This investigation demonstrates that pigeons can be hosts to numerous species, genotypes and subtypes of the studied parasites. Consequently, they represent a potential source of infection for both livestock and humans.

Multidrug resistant Escherichia coli in backyard poultry and captive pigeons in Chattogram, Bangladesh

Bovine babesiosis is the most economically important haemoprotozoan disease caused by Babesia spp. The present study was conducted in selected hilly, coastal and plain areas of Bangladesh to determine the prevalence and identification of risk factors along with the molecular characterization of Babesia spp. Using traditional blood smear examination and Giemsa staining, 1.43% (n=1680) of cattle were was found positive for Babesia infection during this study. The prevalence of babesiosis was 1.17% (7 out of 600 cases) in the hilly areas; 1.67% (10 out of 600 cases) in the coastal areas and 1.46% (7 out of 480 cases) in the plain areas. The prevalence of Babesia spp. was found higher (P>0.05) in crossbred cattle compared to local or indigenous cattle. Seasonal variation of disease prevalence indicated that babesiosis was significantly higher (P

Seasonal effect on semen availability and quality of racing pigeon in Thailand.

Background and Aim:Seasonal variations among geographical regions could influence pigeon semen quality differently. This study aimed to determine the seasonal effect on semen availability and quality of racing pigeons in Thailand to understand and improve breeding management in the country.Materials and Methods:Semen was collected from six fertile captive pigeons once a week during summer (March-June), monsoon (July-October), and winter (November-February) during 2019-2020. The success rate of semen collection and semen quality was determined in each season – by which changes in average temperature, humidity, and photoperiod were obtained.Results:Comparable success rates of semen collection were acquired among different seasons, while varied semen qualities were revealed. The percentages of total motility and progressive motility score of sperm were significantly lowest in summer (66.35±3.40 and 3.88±0.15, respectively) compared to monsoon (85.45±2.91 and 4.67±0.10, respectively) and winter (79.29±1.96 and 4.37±0.10, respectively), while its concentration (×109 sperm/mL) and outputs (×106 sperm) were significantly highest in winter (7.62±0.54 and 91.44±10.83, respectively) compared to summer (4.23±0.41 and 48.45±6.35, respectively) and monsoon (3.57±0.30 and 51.45±7.21, respectively). Besides, semen samples collected from birds housing at an average temperature of <29.5°C demonstrated better sperm motility sperm concentration and total sperm counts than those from at a higher temperature.Conclusion:Winter was regarded as the best season contributing the best semen quality, while summer was the worst. Due to the fluctuation of temperature during summer and winter, the seasonal temperature was implied as the major factor contributing to changes in sperm quality of racing pigeons in Thailand.

Is Allopreening a Stimulus-Driven Defense Against Ectoparasites?

Allopreening occurs when 1 bird preens another bird. The behavior is normally directed at the head and neck of the recipient, i.e., regions that the bird cannot self-preen. Studies of penguins, pigeons, and other groups of birds suggest that allopreening plays a role in the control of ectoparasites, such as ticks and feather lice. However, it is not known whether allopreening increases in response to increases in parasite load, or whether it is a programmed response that occurs independently of parasite load. We conducted a laboratory experiment using wild-caught rock pigeons (Columba livia) to test the relationship between ectoparasite load and allopreening rate. We added feather lice (Columbicola columbae) to captive pigeons and tested for changes in allopreening rates compared to control birds with no lice added. Allopreening rates did not change in response to the addition of lice. Interestingly, however, our data revealed a negative correlation between allopreening and self-preening rates.

The low-down on sleeping down low: pigeons shift to lighter forms of sleep when sleeping near the ground.

Sleep in birds is composed of two distinct sub-states, remarkably similar to mammalian slow-wave sleep (SWS) and rapid eye movement (REM) sleep. However, it is unclear whether all aspects of mammalian sleep are present in birds. We examined whether birds suppress REM sleep in response to changes in sleeping conditions that presumably evoke an increase in perceived predation risk, as observed previously in rodents. Although pigeons sometimes sleep on the ground, they prefer to sleep on elevated perches at night, probably to avoid nocturnal mammalian ground predators. Few studies to date have investigated how roosting sites affect sleep architecture. We compared sleep in captive pigeons on days with and without access to high perches. On the first (baseline) day, low and high perches were available; on the second day, the high perches were removed; and on the third (recovery) day, the high perches were returned. The total time spent sleeping did not vary significantly between conditions; however, the time spent in REM sleep declined on the low-perch night and increased above baseline when the pigeons slept on the high perch during the recovery night. Although the amount of SWS did not vary significantly between conditions, SWS intensity was lower on the low-perch night, particularly early in the night. The similarity of these responses between birds and mammals suggests that REM sleep is influenced by at least some ecological factors in a similar manner in both groups of animals.

Captive and free-living urban pigeons (Columba livia) from Brazil as carriers of multidrug-resistant pathogenic Escherichia coli

Thirty Escherichia coli isolates from captive and free-living pigeons in Brazil were characterised. Virulence-associated genes identified in pigeons included those which occur relatively frequently in avian pathogenic E. coli (APEC) from commercial poultry worldwide. Eleven of 30 E. coli isolates from pigeons, belonging mainly to B1 and B2 phylogenetic groups, had high or intermediate pathogenicity for 1-day-old chicks. The frequency of multi-drug resistant (MDR) E. coli in captive pigeons was relatively high and included one isolate positive for the extended-spectrum β-lactamase (ESBL) gene blaCTX-M-8. Pulsed field gel electrophoresis (PFGE) showed high heterogeneity among isolates. There is potential for pigeons to transmit antibiotic resistant pathogenic E. coli to other species through environmental contamination or direct contact.

Does allopreening control avian ectoparasites?

For birds, the first line of defence against ectoparasites is preening. The effectiveness of self-preening for ectoparasite control is well known. By contrast, the ectoparasite control function of allopreening-in which one birds preens another-has not been rigorously tested. We infested captive pigeons with identical numbers of parasitic lice, and then compared rates of allopreening to the abundance of lice on the birds over time. We documented a negative relationship between rates of allopreening and the number of lice on birds. Moreover, we found that allopreening was a better predictor of louse abundance than self-preening. Our data suggest that allopreening may be a more important means of ectoparasite defence than self-preening when birds live in groups. Our results have important implications for the evolution of social behaviour.

Molecular characterization and genotyping of human related microsporidia in free-ranging and captive pigeons of Tehran, Iran

Microsporidia are opportunistic pathogens in nature infecting all animal phyla. Samples of intestinal content from 147 pigeons from various regions of Tehran (Iran) were analyzed for occurred microsporidia by PCR and sequencing. The DNA isolated from 31 samples (21%) of microsporidia-positive was amplified with specific primers for the four most frequent human microsporidia. Enterocytozoon bieneusi was the most common species and was recognized in thirteen pigeons (42%). Four pigeons were positive for Encephalitozoon intestinalis (12.9%), six for Encephalitozoon hellem (19.3%) and two for Encephalitozoon cuniculi (6.4%). Mixed infections were detected in six another pigeons: E. bieneusi and E. hellem were detected in two cases (4.8%); E. bieneusi was associated with E. intestinalis in one case (0.8%); E. hellem and E. intestinalis coexisted in one; and E. hellem and E. cuniculi were identified in two pigeons. The genotypes of internal transcribed spacer (ITS) of the rRNA gene were determined for all isolates with single infections. Six isolates of E. bieneusi belonged to the genotype D (46.2%), three to the genotype M (23%), and four to the genotype J (30.8%). Sequences of four E. hellem isolates were same to genotype 1A and two were identical with genotype 3. In two cases of the pigeons, E. cuniculi genotype I, II were identified. This study implicates pigeons as potential sources of microsporidia infection for humans.

Development of Nicarbazin Bait for Managing Rock Pigeon Populations

Effective methods for managing populations of rock pigeons and other overabundant avian species are limited. An alternative to lethal control is reproductive inhibition. Nicarbazin is a widely used additive in poultry feed that also reduces hatchability of eggs. It is the active ingredient in OvoControl ® G, a bait product recently registered as a means for reducing hatchability of eggs of urban Canada geese. In a series of trials with captive pigeons, we evaluated the effectiveness of several nicarbazin bait formulations to determine effects on reproduction and to quantify levels of nicarbazin absorbed into the blood. Although pigeons readily accepted a scaled-down version of the OvoControl goose bait, this formulation did not adequately reduce hatchability because of insufficient absorption of nicarbazin into the blood. Other bait formulations that contained 2,500 ppm nicarbazin produced similar results. Only bait formulated with 5,000 ppm nicarbazin produced sufficient amounts of the active ingredient in blood plasma of test birds. Eventual registration of the nicarbazin pigeon bait will provide additional management options for limiting growth of unwanted pigeon populations.

Research Article: Genetic monogamy in captive pigeons (Columba livia) assessed by DNA fingerprinting

Abstract Many socially monogamous birds have been shown to be genetically polygamous, and such behavior can be enhanced in captivity. We verified the monogamous behavior of pigeons (Columba livia) in a captive population using DNA fingerprinting with multilocus minisatellite (Jeffreys') probes. No extra pair offspring were detected when 25 chicks from unique matings were analyzed. Two potentially extra-pair offspring were detected among 43 chicks from matings of socially established pairs produced during a two-year period. That the social pair bond remained unbroken throughout the two years of our study was confirmed by molecular analysis of offspring from sequential matings.

In vivo strains in pigeon flight feather shafts: implications for structural design

To evaluate the safety factor for flight feather shafts, in vivo strains were recorded during free flight from the dorsal surface of a variety of flight feathers of captive pigeons (Columba livia) using metal foil strain gauges. Strains recorded while the birds flew at a slow speed (approximately 5-6 m s-1) were used to calculate functional stresses on the basis of published values for the elastic modulus of feather keratin. These stresses were then compared with measurements of the failure stress obtained from four-point bending tests of whole sections of the rachis at a similar location. Recorded strains followed an oscillatory pattern, changing from tensile strain during the upstroke to compressive strain during the downstroke. Peak compressive strains were 2.2+/-0. 9 times (mean +/- s.d.) greater than peak tensile strains. Tensile strain peaks were generally not as large in more proximal flight feathers. Maximal compressive strains averaged -0.0033+/-0.0012 and occurred late in the downstroke. Bending tests demonstrated that feather shafts are most likely to fail through local buckling of their compact keratin cortex. A comparison of the mean (8.3 MPa) and maximum (15.7 MPa) peak stresses calculated from the in vivo strain recordings with the mean failure stress measured in four-point bending (137 MPa) yields a safety factor of between 9 and 17. Under more strenuous flight conditions, feather stresses are estimated to be 1.4-fold higher, reducing their safety factor to the range 6-12. These values seem high, considering that the safety factor of the humerus of pigeons has been estimated to be between 1.9 and 3.5. Several hypotheses explaining this difference in safety factor are considered, but the most reasonable explanation appears to be that flexural stiffness is more critical than strength to feather shaft performance.

Germination of miro (Prumnopitys ferruginea) seeds after consumption by New Zealand pigeons (Hemiphaga novaeseelandiae)

Abstract Fruits of miro (Prumnopitys ferruginea), a large podocarp tree, are commonly eaten by New Zealand pigeons (Hemiphaga novaeseelandiae), and defecated as intact seeds. To test if germination is affected by passage of seeds through a pigeon gut, ripe miro fruit were fed to captive pigeons and defecated seeds were collected. These seeds were planted and their germination rates were compared with those of uneaten ripe fruits, planted at the same time. No seeds germinated for 18 months, but thereafter germination continued for over 4 years from planting. There was considerable variation (5-100%) in germination rate between replicates and no significant difference in overall germination rate between seeds which had and had not passed through a pigeon gut.

Seed Selection By Pigeons

The food preferences of 59 captive Pigeons Columbia livia were tested in a series of experiments in which each bird was given a 25 g. seed mixture. This consisted of 5 g. each of Maize, Millet, Grain (Wheat, Oats and Barley), and two varieties of Field Pea (Big Peas and Small Peas). There was a wide range of individual variation. Most birds preferred Peas, and took little Maize; however, others actually preferred minority seeds such as Maize. These individual preferences were stable over short periods, though there were gradual, long-term changes in birds tested repeatedly over a period of four months. There were also individual differences in feeding technique, though these could not be correlated with the differences in seed preference. The origins of these individual variations are discussed. It was not possible to relate them to individual differences in bill size, nor to the proportions of the seeds in the birds' normal feed. When the total quantity of the experimental seed mixture was increased from 25 g. to 50 g., the birds increased their total intake while keeping constant the proportions of the different seeds in it. Since the seeds differ in nutritional composition, it is suggested that the birds were maintaining a nutritionally balanced diet. It is possible that the variations in seed preference may reflect individual differences in metabolism. Individual birds also maintained a constant ratio of Big Peas to Small Peas in their seed intake, even though these differ little, if at all, in nutritional content. It is suggested that such apparently arbitrary food choices might increase the efficiency of the birds' food-finding tactics. Some ecological implications are briefly outlined. If feeding is controlled by the quality as well as the quantity of available food, this could influence the extent to which the birds exploit their environment, and the degree to which their numbers are limited by the food supply.