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In urban areas, organisms are exposed to high pollutant levels, especially element trace metals that may impact host-parasite interactions. Indeed, parasites have been reported to reduce the negative effects of pollutants on their hosts. The fitness of parasitized organisms in polluted environments may therefore be greater than that of unparasitized organisms. In our study, we used an experimental approach to test this hypothesis on feral pigeons (Columba livia), which are endemically parasitized by nematodes and exposed to high levels of lead in urban areas. We tested the combined effects of lead exposure and helminth parasitism on different pigeon fitness components: preening, immunocompetence, abundance of lice (Columbicola columbae) and haemosporidian parasites (Heamoproteus spp., Plasmodium spp.), reproduction investment, and oxidative stress. Our results show that among pigeons exposed to lead treatment, individuals harboring nematode parasites exhibit more preening activity and have fewer ectoparasites lice than nematode-free individuals. Benefits for nematode-parasitized individuals exposed to lead were not detected for other fitness parameters. Further studies are required to confirm the "parasite detoxification hypothesis" in pigeons and to identify the mechanisms by which this detoxification occurs. [ABSTRACT FROM AUTHOR]

The European Turtle Dove Streptopelia turtur is a trans‐Saharan migratory species that has been declining for decades. This study reports nesting habitat, nest‐site characteristics, nesting success (38.6%) and productivity (2.40 young per pair per season) of European Turtle Doves radiotracked in a deciduous forest of western France. A matrix population model based on our results suggests that the average productivity reported would need to be increased by about 0.18 additional young per pair to achieve a population growth rate equal to one. However, elasticity analysis suggests that increasing adult survival would have the highest impact on population growth compared with increased productivity or first‐year survival. [ABSTRACT FROM AUTHOR]

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This review collated existing data on the occurrence, distribution, and prevalence of haemoparasites of poultry in sub-Saharan Africa. A literature search was conducted on three electronic search databases using search terms and Boolean operators (AND, OR). The results recorded 16 haemoparasites, viz., Leucocytozoon spp., L. marchouxi, L. neavei, L. sabrazesi, L. schoutedeni, Haemoproteus columbae, H. pratasi, Haemoproteus spp., Plasmodium spp., P. gallinaceum, P. circumflexum, P. juxtanucleare, Trypanosoma avium, T. gallinarum, T. numidae, and Hepatozoon spp. from a wide range of poultry species distributed across Nigeria, Kenya, South Africa, Tanzania, Uganda, Botswana, Zimbabwe, Ghana, Cameroon, and Zambia. Infections due to Haemoproteus and Leucocytozoon species were the most common and documented in eight of the ten reviewed countries. The presence of mixed infections was observed in quails, pigeons, chickens, ducks, turkeys, and guineafowls, but predominantly in chickens. Co-infections by Plasmodium spp. and Haemoproteus spp. were the most common, which may be attributed to the distribution of these species, coupled with the availability of vectors they are associated with in areas from which they were documented. The information generated in this review is essential for improving existing preventive and control measures of these parasites in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

Investigation of the negative impacts of stress on reproduction has largely centered around the effects of the adrenal steroid hormone, corticosterone (CORT), and its influence on a system of tissues vital for reproduction-the hypothalamus of the brain, the pituitary gland, and the gonads (the HPG axis). Research on the action of CORT on the HPG axis has predominated the stress and reproductive biology literature, potentially overshadowing other influential mediators. To gain a more complete understanding of how elevated CORT affects transcriptomic activity of the HPG axis, we experimentally examined its role in male and female rock doves (Columba livia). We exogenously administrated CORT to mimic circulating levels during the stress response, specifically 30 min of restraint stress, an experimental paradigm known to increase circulating CORT in vertebrates. We examined all changes in transcription within each level of the HPG axis as compared to both restraint-stressed birds and vehicle-injected controls. We also investigated the differential transcriptomic response to CORT and restraint-stress in each sex. We report causal and sex-specific effects of CORT on the HPG transcriptomic stress response. Restraint stress caused 1567 genes to uniquely differentially express while elevated circulating CORT was responsible for the differential expression of 304 genes. Only 108 genes in females and 8 in males differentially expressed in subjects that underwent restraint stress and those who were given exogenous CORT. In response to elevated CORT and restraint-stress, both sexes shared the differential expression of 5 genes, KCNJ5, CISH, PTGER3, CEBPD, and ZBTB16, all located in the pituitary. The known functions of these genes suggest potential influence of elevated CORT on immune function and prolactin synthesis. Gene expression unique to each sex indicated that elevated CORT affected more gene transcription in females than males (78 genes versus 3 genes, respectively). To our knowledge, this is the first study to isolate the role of CORT in HPG genomic transcription during a stress response. We present an extensive and openly accessible view of the role corticosterone in the HPG transcriptomic stress response. Because the HPG system is well conserved across vertebrates, these data have the potential to inspire new therapeutic strategies for reproductive dysregulation in multiple vertebrate systems, including our own.

Hormones mediate physiological and behavioral changes in adults as they transition into reproduction. In this study, we characterize the circulating levels of five key hormones involved in reproduction in rock doves (Columba livia): corticosterone, progesterone, estradiol, testosterone, and prolactin using univariate and multivariate approaches. We show similar patterns as previous studies in the overall patterns in circulating levels of these hormones, i.e., testosterone (males) and estradiol (females) high during nest-building or egg-laying, prolactin increasing at mid-incubation and peaking at hatching (both sexes), and elevated corticosterone levels in later incubation and early nestling development. In our investigation of hormone co-variation, we find a strong correlation between prolactin and corticosterone across sampling stages and similarities in earlier (early to mid-incubation) compared to later (late incubation to nestling d9) sampling stages in males and females. Finally, we utilized experimental manipulations to simulate nest loss or altered caregiving lengths to test whether external cues, internal timing, or a combination of these factors contributed most to hormone variation. Following nest loss, we found that both males and females responded to the external cue. Males generally responded quickly following nest loss by increasing circulating testosterone, but this response was muted when nest loss occurred early in reproduction. Similar treatment type, e.g., removal of eggs, clustered similarly in hormone space. These results suggest internal drivers limited male response early in reproduction to nest loss. In contrast, circulating levels of these hormones in females either did not change or decreased following nest manipulation suggesting responsiveness to external drivers, but unlike males, this result suggests that reproductive processes were decreasing.

BackgroundThe process of alternative splicing provides a unique mechanism by which eukaryotes are able to produce numerous protein products from the same gene. Heightened variability in the proteome has been thought to potentiate increased behavioral complexity and response flexibility to environmental stimuli, thus contributing to more refined traits on which natural and sexual selection can act. While it has been long known that various forms of environmental stress can negatively affect sexual behavior and reproduction, we know little of how stress can affect the alternative splicing associated with these events, and less still about how splicing may differ between sexes. Using the model of the rock dove (Columba livia), our team previously uncovered sexual dimorphism in the basal and stress-responsive gene transcription of a biological system necessary for facilitating sexual behavior and reproduction, the hypothalamic-pituitary-gonadal (HPG) axis. In this study, we delve further into understanding the mechanistic underpinnings of how changes in the environment can affect reproduction by testing the alternative splicing response of the HPG axis to an external stressor in both sexes.ResultsThis study reveals dramatic baseline differences in HPG alternative splicing between males and females. However, after subjecting subjects to a restraint stress paradigm, we found a significant reduction in these differences between the sexes. In both stress and control treatments, we identified a higher incidence of splicing activity in the pituitary in both sexes as compared to other tissues. Of these splicing events, the core exon event is the most abundant form of splicing and more frequently occurs in the coding regions of the gene. Overall, we observed less splicing activity in the 3'UTR (untranslated region) end of transcripts than the 5'UTR or coding regions.ConclusionsOur results provide vital new insight into sex-specific aspects of the stress response on the HPG axis at an unprecedented proximate level. Males and females uniquely respond to stress, yet exhibit splicing patterns suggesting a convergent, optimal splicing landscape for stress response. This information has the potential to inform evolutionary theory as well as the development of highly-specific drug targets for stress-induced reproductive dysfunction.

Correction to: Feather stable isotopes ( 2 Hf and 13Cf) identify the Sub-Saharan wintering grounds of turtle doves from Europe Here, we converted the Hobson et al. ([1]) equation to derive a I i SP 2 sp H SB f sb isoscape and incorporated it into a multivariate assignment to origin analysis with I i SP 13 sp C SB f sb as described in Marx et al. ([2]) to determine possible regions of moult origin of turtle doves. 1Revised (A) and original (B) assignment to likely wintering origin (moulting areas of winter-grown primary feathers) of European turtle doves (n = 181) sampled in seven different European countries (see Fig. [Extracted from the article]

Background and Aim: Avian metapneumovirus (aMPV) is a recently discovered respiratory virus in chickens. Avian metapneumovirus has been linked to respiratory syndromes, reproductive failure in affected chickens and turkeys, swollen head syndrome in chickens, and rhinotracheitis in turkeys. Wild birds are considered potential reservoirs of aMPV, particularly aMPV-C. However, little is known about the prevalence of aMPV in Saudi Arabia. Considering the relevance of backyard chickens in the transmission and sustainability of certain avian viral diseases, this study aimed to assess aMPV exposure in backyard chickens and wild birds circulating near selected locations. Materials and Methods: We collected 368 serum samples from unvaccinated backyard chickens in ten locations in Eastern Saudi Arabia. Furthermore, we collected 78 serum samples from species of free-ranging birds belonging to the Columbidae family, such as pigeons and doves, captured from the same areas. Using commercial enzyme-linked immunosorbent assay kits, we tested the sera of domestic backyard chickens and wild birds for antibodies against aMPV. Results: Our results showed that 74/368 birds were positive for aMPV-related antibodies. Conversely, none of the tested wild birds seroconverted to aMPV. Conclusion: The antibody titers detected in the backyard chickens suggested recent exposure to aMPV. Considering these results, further large-scale serological and molecular studies are needed to evaluate the prevalence of aMPV in these birds and characterize the circulating strains of aMPV in this region. [ABSTRACT FROM AUTHOR]

While hunting wild animals may be considered a problem for conserving native fauna, they can represent an essential part of the diet for some human communities, such as those living in rural areas. Therefore, regulations to combat overhunting should be designed to accommodate the needs of local communities dependent on hunting as a source of food and income in a sustainable way. We interviewed local residents in three communities and wildlife specialists in Sergipe, NE Brazil, where the hunting of columbids is common both for subsistence and leisure, about their perceptions of Columbidae hunting using a semi-structured questionnaire. Most residents defend hunting and make regular use of columbids, suggesting quota hunting as a way of reconciling the practice with the conservation of the species while also noting that columbid populations are decreasing. The wildlife and conservation specialists are opposed to hunting and propose improvement of the socioeconomic status of the residents to mitigate the hunting problem, while also noting that the national environmental agency (IBAMA) is understaffed and underfunded, and there is a lack of adequate reliable data on columbid populations to adequately assess the impact of hunting. [ABSTRACT FROM AUTHOR]

The conventional wisdom in international relations holds that an actor's past record of keeping her word determines her cooperative credibility, and that mutual perceptions of credibility are essential in sustaining cooperation. Yet competing reputation-skeptic and psychological perspectives dispute this conventional wisdom, suggesting that assessments of cooperative credibility result from observers' judgments about the other's capabilities and interests or observers' foreign policy orientations. How do observers assess others' cooperative credibility? We field a nationally representative survey experiment asking 2,953 Americans to evaluate a hypothetical coercer's commitment to lift sanctions on a would-be proliferator in exchange for the latter dismantling its nascent nuclear program. We vary the coercer's previous behavior plus several other contextual factors. We find that respondents' hawkishness interacts with the coercer's past actions to shape respondents' credibility assessments and their support for the proliferator accepting the proposal, with substantial implications for theories of misperception and bargaining. [ABSTRACT FROM AUTHOR]

Objective: The study investigated the gut content and recorded morphometric and hematological parameters in the Eurasian collared dove (Streptopelia decaocto). Materials and Methods: 24 samples of healthy birds (12 from each sex) were collected from different wetlands in Punjab, Pakistan, from December 2022 until February 2023. Birds were captured live for blood samples, morphometric, and gut analyses. Results: The current study revealed that mensural measurements showed no significant differences in all parameters except tail length, which was significantly longer in males (14.59 ± 0.30) compared to females (12.88 ± 0.43). Hematological parameters were hemoglobin, 23.95 gm/dl; red blood cells, 3.97 × 106 /µl; white blood cells, 429.9.67 × 10³ /µl; hematocrit, 72.14%; mean corpuscular volume, 183.24 FL; mean corpuscular hemoglobin, 61.70 pg; mean corpuscular hemoglobin concentration, 32.37 pg; platelets, 7.01/µl; and red cell distribution width, 110.86/µl. The percentages of neutrophils, lymphocytes, monocytes, and eosinophils were 71.33%, 23.03%, 3.30%, and 1.43%, respectively. The gut content of the Eurasian collared dove mainly consisted of rice, wheat, corn, and millet seeds. Some stony materials were also present. Conclusion: Our study concluded that male and female Eurasian collared doves are alike in biometrics (except tail length) and hematological profiles. Gut content and weight were also similar. Males were slightly larger than females. The gut content showed that the Eurasian collared dove mainly feeds on rice, wheat, corn, and millet seeds. In this study, hematological parameters were also studied. [ABSTRACT FROM AUTHOR]

What prolonged implications does conflict escalation have on voting behavior? The literature focuses primarily on the immediate effect of violent events on voting in nearby elections, leaving open questions about longer-term consequences. This article examines this question by studying Israel, where violent escalation in the Israeli–Palestinian conflict in the early 2000s was followed by an unexpected electoral outcome: the emergence and consolidation of a new centrist bloc that transformed a longstanding Left-Right partisan divide into a three-bloc system. Using two decades of survey data, it is argued that this shift is best explained by a long-term attitudinal change toward the conflict by many Israelis after the escalation. Rather than a strictly hawkish shift, many voters have become 'Doubtful Doves': supportive of territorial compromise in principle, but skeptical about reaching an agreement with the Palestinians in practice. This underdiscussed attitudinal structure, dovish but doubtful, has formed a new electoral base for centrist parties, breaking the traditional Left-Right dichotomy. These findings illustrate that violent periods in conflicts can cause non-trivial long-term changes in popular attitude structures and voting patterns, which, under the right conditions, can trigger electoral re-equilibration. [ABSTRACT FROM AUTHOR]

The native breed of chicken is one of the most income-producing species in the poultry sector in the Egyptian governorate of Ismailia. Thus, the objective of the current study was to identify the collected parasites using a light microscope and estimate the prevalence and seasonal dynamics of the collected helminths using the newly introduced molecular biology methods. 120 chickens out of 170 recorded (70.59%) prevalence of helminth infestation during the period from September 2021 until the end of August 2022. Four nematodes with a prevalence of 44.12 %, which were Ascaridia galli, Heterakis gallinarum, Subulura brumpti, Trichostrongylus tenuis, and four cestodes with 26.47 %, which were Raillietina tetragona, R. echinobothrida, Hymenolepis carioca, and Choanotaenia infundibulum. Eimeria spp. infestation (11.18%), which were E. tenella, E. maxima, E. mitis, and E. brunetti. Ectoparasites (15.88%) were Echidnophaga gallinacea, Lipeurus caponis, Menopon gallinae, Columbicola columbae, and Dermanyssus gallinae. The identities of the certainly recovered nematode and cestode species were confirmed by the blast test using DNA sequence data. Thus, it is advised to use the molecular approach as the primary methodology for the accurate identification of helminths, particularly in closely related species. [ABSTRACT FROM AUTHOR]

Penentuan jenis kelamin pada beberapa spesies burung cukup sulit dilakukan dikarenakan jantan dan betina memiliki ciri morfologi yang sama (monomorfik), salah satunya famili Columbidae. Teknik penentuan jenis kelamin burung secara molekuler yang populer adalah metode Polymerase Chain Reaction (PCR) dengan gen target Chromo Helicase DNA-binding (CHD), namun keberhasilan amplifikasi gen target pada PCR tersebut dipengaruhi salah satunya kesesuaian DNA template dengan primer yang digunakan. Penelitian ini bertujuan untuk mengevaluasi 5 jenis primer PCR P2/P8, 2550F/2718R, CHD1F/CHD1R, 1237L/1272H dan CHD1LF/CHD1LR untuk menentukan jenis kelamin famili Columbidae. Penelitian ini dilakukan dengan menguji 5 jenis primer tersebut di atas pada sampel DNA tiap pasang jantan dan betina dari burung merpati, balam jambi, punai, derkuku, dan perkutut. Hasil penelitian diketahui primer CHD1LF/CHD1LR menunjukkan hasil terbaik dan direkomendasikan untuk menentukan jenis kelamin famili Columbidae.

This study aimed to evaluate the spatial microdistribution and temporal microdistribution of the North African subspecies of the globally threatened Turtle Doves in Morocco. From the end of February to early September, we monitored the migration dates, counting arrival and departure dates, and breeding chronology, to clarify if the breeding season is divided into sub-breeding phases or not. Equally, the spatial distribution of nests following potential breeding phases was surveyed weekly in Beni Mellal province following a map of a selected orange orchard. Doves arrived in Beni Mellal in the third week of March and left in mid-October, according to the results. The first nests occurred in the second week of April, followed by the first eggs in the third week of April and the first chicks in the first week of May. PCA analysis showed that the nesting and laying stages were achieved principally during the last two weeks of April and the first three weeks of May, the hatching stage between the fourth week of May and the second week of July, and fledging between the fourth week of July and the first week of September. Further, the breeding season was divided into two phases: the first breeding phase, from the first week of April to the first week of June, and the second phase, between the second week of June and the second week of August. The DCA analysis and orchard-created map indicated that the first wave of breeders colonized the marginal trees located on the orchard sides, surrounded by foraging cereals and legumes, and the second breeding-phase nests were constructed in flocks next to the nests of the first breeding phase. According to this strategy, the first breeders prospect the orchard and select nesting trees near foraging resources, while the second breeders' wave colonizes trees near successfully used prospector sites. These findings are of great importance for comparative investigations and habitat-scale conservation management. [ABSTRACT FROM AUTHOR]

The current study was conducted to investigate the efficacy and stability of D‐limonene (DL) and its nanoemulsion (DLN) against pigeon feather lice (Columbicola columbae) and their mode of action. DL pure form and DLN were prepared and characterized freshly and after storage for 50 days. In vitro bioassay on live lice was conducted with different concentrations of DL, DLN, and deltamethrin (DM). The results revealed significant mortality rates in the DL‐, DLN‐, DM‐treated groups when compared with the control (p < 0.05). The scanning electron micrographs of lice treated with DL and DLN revealed collapsed bodies with destruction in the cuticle of the mouthparts and damaged antennae. The 50 days stored DLN showed stability in their effectiveness when compared with the freshly prepared formulation. DL and DLN caused significant inhibition (p ≤ 0.05) in acetylcholinesterase activity (AchE). Malondialdehyde level (MDA) was significantly increased while glutathione was significantly decreased in DL‐ and DLN‐treated lice. In conclusion, DL and DLN have significant lousicidal activities. DLN showed better stability than DL after storage for 50 days. In addition, the mode of action of DL may associate with its effect on the cuticle of the lice body, inhibition of AchE, and increasing oxidative stress in the treated lice. [ABSTRACT FROM AUTHOR]

The identification of migration dates and wintering zones for migratory birds are key elements for the understanding of the Afro‐Palearctic migration system. From 2015 to 2022, a large‐scale survey of Turtle Doves Streptopelia turtur, a vulnerable species, was established in Northwest Africa, including Morocco, Algeria, and Tunisia. We monitored migration dates and wintering individuals using the line‐transect method. We found that Turtle Doves arrived in the last week of March and left the North African region in mid‐October. Compared with Morocco, Doves arrived significantly earlier in Algeria and Tunisia. Moreover, Doves were discovered wintering on nine Northwest African sites, from October to February, where individuals feed in groups. We found that the occurrence probability of wintering Turtle Doves decreased significantly with increasing temperature and rainfall. Birds wintered most often close to wetlands since the overwintering probability decreased with the increasing distance from the recording area to the nearest water body. These are the first and only detailed findings on the migration phenology of the globally vulnerable Turtle Dove in north western Africa. [ABSTRACT FROM AUTHOR]

Molting is an important process in which old and worn feathers are exchanged for new ones. Plumage color is determined by pigments such as carotenes, melanin and by the ultrastructure of the feather. The importance of plumage coloration has been widely studied in different groups of birds, generally at a particular time of the year. However, plumage coloration is not static and few studies have addressed the change in plumage color over time and its relationship to reproductive tasks. The Eared Dove (Zenaida auriculata, Des Murs, 1847) has a melanistic coloration with sexual dichromatism in different body regions. The Eared Dove´s crown is the most exposed body region during the bowing display. Our objective was therefore to accurately determine the molting period of the crown feathers and study the seasonal variation in their coloration in females and males. Our findings indicate a molting period of 6 months (January to June). The new feathers are undergoing changes in their coloration from July to December. During that period we apply an avian vision model then enabled us to reveal a seasonal variation in the coloration of the crown feathers in both sexes, as given by a change in the chromatic distances. The highest values in the chromatic distances towards the reproductive period are given by a change in the UV-violet component of the spectrum, indicating changes in the microstructure of the feather. This change in crown coloration towards the breeding season could be linked to reproductive behaviors. [ABSTRACT FROM AUTHOR]

Simple Summary: The European turtle dove (Streptopelia turtur) is a migratory species that overwinters in sub-Saharan Africa, migrating to Europe each spring to breed. Over the past four decades, turtle dove populations have declined by as much as 79%, making the species vulnerable to extinction. A major threat to the species is illegal killing (poaching) during its spring migration through the Mediterranean coasts of Europe. According to the international action plan for the conservation of the species, eradicating this threat is key for reversing the European turtle dove population declines by 2028. In this study, we used a network of acoustic sensors to record the gun hunting pressure at known hunting sites in the Ionian Islands, Greece—a known poaching hot-spot—over four spring migrations (2019–2022). Based on the number of gunshots recorded, we estimate that up to 57,095 turtle doves were killed or injured across the region in 2021. We anticipate that these findings will generate the resolve needed among responsible authorities to eradicate the spring migration in the Ionian Islands, and propose the roll out acoustic monitoring grids in additional poaching hot-spots along the migration routes of the turtle dove. The European turtle dove (Streptopelia turtur) is an Afro-Palearctic migrant whose populations have declined by 79% from 1980 to 2014. In 2018, the International Single Species Action Plan for the Turtle Dove (ISSAP) was developed with the goal of enabling, by 2028, an increase in turtle dove numbers along each of the three migration flyways (western, central, eastern). To achieve this, the illegal killing of turtle doves, a critical threat to the species, has to be eradicated. The Ionian Islands off the west coast of Greece lie on the eastern flyway and are considered a major turtle dove poaching hot-spot during spring migration. Quantifying wildlife crime, however, is challenging. In the absence of a reliable protocol for monitoring spring poaching levels, the agencies tasked with tackling the problem have no means of assessing the effectiveness of the anti-poaching measures and adapting them if required. Using passive acoustic monitoring (PAM) methods, we recorded gun hunting intensity at known turtle dove poaching sites during the 2019–2022 spring migrations (2–10 sites/season) with unprecedented spatial and temporal resolution. Based on published gunshot to killed/injured bird ratio for similar species (corroborated with discussions with local hunters) and an estimate of the proportion of hunting sites monitored by our PAM grid (using gunshot detection range estimates from control gunshots), we estimated that in 2021, up to 57,095 turtle doves were killed or injured across five Ionian Islands (Zakynthos, Paxi, Antipaxi, Othoni, and Mathraki). The 2022 estimate was almost half, but it is unclear as to whether the change is due to a decline in poachers or turtle doves. We propose ways of improving confidence in future estimates, and call for a temporary moratorium of autumn turtle dove hunting in Greece—as per ISSAP recommendation—until spring poaching is eradicated and the eastern flyway population shows signs of a full recovery. Finally, we hope our findings will pave the way for the development of PAM grids at turtle dove poaching hot-spots across all migration flyways, contributing to the global conservation of the species. [ABSTRACT FROM AUTHOR]

Human disturbance might be perceived as a threat by animals and interfere in their vital activities. Urbanisation generates changes in habitat structure that allows only a low number of species to adapt, which results in a decrease of species richness and an increase of the abundance of a few dominant species. To survive in urbanised areas, animals need to be highly tolerant to human approximation. One key characteristic of successful invasive species is their high behavioural plasticity. This plasticity could translate to higher chances of surviving in urbanised areas and becoming tough competitors for native species. The Eurasian collared-dove is a successful invader in Europe, it arrived to México during the nineties and has been spreading in the country since. We compared its tolerance to human approximation to that of the already well-established feral pigeon and other native species in agricultural and urban sites. We found the Eurasian collared-dove is less tolerant to humans than the feral pigeon, but more tolerant than native species. Also, we observed that birds showed higher tolerance to humans in urban areas than in agricultural sites, regardless of the species. Interestingly, feral pigeons restrained their distribution to human settlements, and acting as a counterpart, common ground doves were only found in rural sites. However, the Eurasian collared-dove was present also in agricultural areas, which could suggest the Eurasian collared-dove represents a higher threat than the feral pigeon for native species in our study area. We highlight the importance to further understand the behavioural traits that could promote the Eurasian collared-dove invasion to better design management plans for dove diversity in urban areas. [ABSTRACT FROM AUTHOR]

The European turtle dove Streptopelia turtur (hereafter turtle dove), is a widespread species in the Palearctic. Due to a large and rapid decline in its abundance, it was classified as "vulnerable" on the International Union for Conservation of Nature's Red List in 2015 and is now regarded as a globally threatened species. The objective of this study was to provide new information on the flyways of this turtle dove population by analyzing available ring recoveries and citizen science sightings data from the Global Biodiversity Information Facility. A new flyway (possibly stretching through the Black and Caspian Seas, Turkey, the Middle East, and Egypt toward the Eastern Sahel) is suggested for turtle doves breeding in Northern and Eastern Europe. [ABSTRACT FROM AUTHOR]

The Swahili poem of "The Hawk and the Dove" (Kozi na Ndiwa) has long been popular along the Swahili coast. In brief, the poem tells the story of the prophet Musa, who is put to the test by the angels Mikaili and Jibrili, disguised as a dove and a hawk. The dove, fleeing the famished hawk, finds refuge in the folds of Musa's clothes. The bird of prey, approaching Musa, claims its right to the dove, since it is hungry. Musa faces a dilemma: he understands the hawk's argument but is also full of pity for the dove. When he finally offers to cut off a part of his own right thigh to feed the hawk, the birds reveal themselves as the two angels and praise the prophet. "The Hawk and the Dove" has been a travelling Islamic poem par excellence : like many other popular Swahili Islamic poems dating back to the eighteenth, but mostly the nineteenth century – the heyday of Swahili Islamic poetry, having flourished amid the Sufi movements and their emphasis on poetry in vernacular languages as a means to ignite religious zeal in wider audiences – the poem is also based on sources that have widely travelled the Indian Ocean. Swahili poets creatively adapted them into Swahili verse, just as other Muslim poets in North Africa, West Africa, and, earlier, the Iberian Peninsula did for the discourses relevant to their own contexts. This contribution takes the double optic of providing a first text edition of the most ancient surviving Swahili manuscript of the poem. Secondly, I view the poem amid a longer history of circulation beyond the Swahili coast, as well as compare it with other popular, vernacular versions in the Arabic dialect of Algeria, Hausa in Nigeria, and the earlier adaptations by moriscos from the Iberian Peninsula in Aljamiado. This kaleidoscope of various rewritings of the story allows me to see the Swahili-specific readings more clearly in contrast. [ABSTRACT FROM AUTHOR]

On 13 January 2019, an individual Oriental turtle dove (Streptopelia orientalis Latham, 1790) was recorded. The species is shortly observed during tree-perching in an intensive agricultural landscape near Temerin Town, Vojvodina Province, Northern Serbia. The observed dove was a putative juvenile bird belonging to the subspecies meena. This finding represents the first observation of the Oriental turtle dove and the sixth native species from the order of Columbiformes recorded in Serbia. [ABSTRACT FROM AUTHOR]

Arab women bear the struggle of their local tradition in their countries and the tradition of the Westerns when they live between them. They are victims of gender discrimination and racism. Ethnocentrism is the inclination of people who consider their customs, civilizations, culture, skin, and colour superior, demanding others to follow and imitate them. This paper examined the influence of ethnocentrism on Arab women in Arabian and Western countries by analysing Fadia Faqir’s The Cry of the Dove (2007). The framework in this study is guided by ethnocentrism as a concept in postcolonial theory. The findings revealed that (i) due to ethnocentrism, Arab women suffer gender discrimination, violence, marginalisation, slavery, and death, (ii) Western ethnocentrism abuses and dehumanises the Arab women immigrants, and (iii) ethnocentrism creates many chronic social and political diseases in the minds of people (colonizers, colonized and decolonized people, men and women ), (iv) and some Arab women view the Western world as a unique model that should be imitated. [ABSTRACT FROM AUTHOR]

Adopting a combination of qualitative textual analysis, human-based content analysis, and machine learning–based data mining, we propose a procedure to analyze user-generated content (UGC) on social media using Dove's "Campaign for Real Beauty" as a case for demonstration. We provide a guideline to explicate all six steps of the analysis procedure: topic identification through qualitative textual analysis, generation of labeled data through human coding, data preprocessing, evaluation of machine learning–based classifiers, topic classification of unlabeled data, and conducting research. The study has important methodological implications for advertising scholars and practitioners. [ABSTRACT FROM AUTHOR]

The Order of March 13, 2024, approved by the Minister of Economic Development, Sustainability and Environment, establishes the Management Plan for the European turtle dove (Streptopelia turtur) in the Autonomous Community of the Basque Country. The European turtle dove has been included in Annex II of the Birds Directive 2009/147/EC, which allows for its hunting within the framework of national legislation. However, a decrease in the breeding population of this species has been observed in the Basque Country, leading to its inclusion in the category of "Endangered". Factors that have contributed to this situation include the conversion of agricultural systems, the use of phytosanitary products, and excessive urbanization of countryside areas. The management plan aims to protect and conserve the European turtle dove in the region. [Extracted from the article]

Não se decepcionem os que ao compulsarem o presente trabalho, e os outros que por ventura Ihe venham a seguir a esteira, nada encontrem capaz de lembrar as grandes monografias que a intervalos vemos enriquecer a literatura ornitológica, abrindo às vezes perspectivas imprevistas ao estudo cientifico das Aves, ou trançando novos rumos ao progresso dos conhecimentos relacionados com o seu domínio. Verdade é que, inicialmente, prendeu-se ele a ideia, longo tempo acarinhada, de um tratado descritivo das Aves do Brasil, do qual o Catálogo por nos publicado anos atrás seria o arcabouço e alicerce. Mas, a vista da manifesta impossibilidade, criada pelas circunstancias, de levar avante a tentadora empresa, imaginamos imprimir aos nossos trabalhos orientação nova, apresentando em forma singela, e sem grandes compromissos com as praxes rigidamente seguidas pelos especialistas, o compendio da historia natural de alguns grupos, cingindo-nos a sua representação no solo pátrio e escolhendo-os entre os que a experiência. demonstra interessarem mais particularmente, por este ou aquele motivo, os amantes de nossa natureza e os poucos entre nos afeiçoados ao seu estudo. Neste sentido e este esboço da fauna brasileira de Columbidas a primeira tentativa; tentativa ainda assim algo frusta, porque entre os fatores a conspirar contra o seu melhor acabamento esteve sempre à hostilidade constante de estranhas preocupa?6es, e a escassez de tempo para uma aplicação continuada.

Interspecific hybridization occurs among birds, and closely related sister taxa tend to hybridize at a high rate. Genomic hybridization markers are useful for understanding the patterns and processes of hybridization and for conserving endangered species in captivity and the wild. In this study, we developed genomic hybridization markers for the F1 progeny of the sister taxa feral pigeons (Columba livia var. domestica) and endangered hill pigeons (Columba rupestris) (family Columbidae). Using whole-genome re-sequencing data, we performed genome-wide analysis for insertion/deletion (InDel) polymorphisms and validated using primers. We conducted polymerase chain reaction (PCR) and agarose gel electrophoresis to identify species-specific InDels. We produced eight F1 hybrids of hill and feral pigeons, and their samples were tested by re-performing analyses and sequencing using 11 species-specific InDel polymorphisms. Eight InDel markers simultaneously amplified two DNA fragments from all F1 hybrids, and there was no abnormality in the sequencing results. The application of genomic tools to detect hybrids can play a crucial role in the assessment of hybridization frequency in the wild. Moreover, systematic captive propagation efforts with hybrids can help control the population decline of hill pigeons. [ABSTRACT FROM AUTHOR]

We made an analysis of the osteological remains of prey that had been captured by the peregrine falcon (Falco peregrinus) and was collected from eyries perched high in rocky cliffs of Slovakia. Birds dominated the 7,233 vertebrates identified (class Aves, with minimum of 98 species and 97.2% of the total). Bones from mammals (class Mammalia, 24 species, 2.5%) were rarely found, and sporadic remains from lower vertebrate species (classes Amphibia, Reptilia, Pisces, 0.3%) were also noted. The collected specimens were divided over three distinct periods. Before domestic pigeons became a major component in the juvenile peregrine falcon diet (Period A), wild pigeons and doves were the most common prey; specifically stock doves (Columba oenas) caught at lower elevations, and wood pigeons (Columba palumbus) in mountainous areas. The Eurasian woodcock (Scolopax rusticola) was a frequent prey. The diversity of peregrine falcon diet reached its maximum between the 1930s and the 1950s (Period B), with the domestic pigeon (Columba livia domestica) present in the diet at a similar abundance (16.1%) to wild pigeons and doves. The peregrine falcon population tailed off in the 1960s as pesticides became more commonly used in agriculture. A new population started expanding from Western Europe during the 1990s and has stabilised at around 150 breeding pairs in recent years. Since the turn of the millennium (Period C), domestic pigeons have become the dominant prey (51.1%) along with smaller songbirds such as hawfinches (Coccothraustes coccothraustes) and common starlings (Sturnus vulgaris), at 15.5% and 14.6% of total osteological remains collected, respectively. [ABSTRACT FROM AUTHOR]

The Common Wood Pigeon (Columba palumbus Linnaeus, 1758) has very large populations in the European cities. However, the urbanisation of the species in the Maros–Körös köze region (Maros–Körös Interfluve) is recent and is happening before our eyes. In our study, we summarized our observations on the urbanised populations of the species in the region. Populations of the species in populated areas are currently spreading rapidly in the Maros–Körös köze region. In the past, it was a breeding species in the landscape of suburban areas far from populated areas. In recent years, it has appeared in towns and villages. It did not gradually arrive from the outer area of the settlements towards the interior of populated areas, but it was precisely in the park areas of the centres of settlements that the first pairs in these areas appeared and spread outwards. During the study, we also surveyed the nesting populations of the Eurasian Collared Dove (Streptopelia decaocto [Frivaldszky, 1838]) in the sampling areas, using the same methodology, so that we could also examine the proportion of both urbanised species. The population of that species was decreasing during the study period. The pairs of Common Wood Pigeons were more common in the central, more parked parts of the settlements, while the Eurasian Collared Dove was mainly found in peripheral areas. The increase in the population of the Common Wood Pigeons will cause major problems for agriculture, for which there is no solution at present. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The wedge-tailed green pigeon (Treron sphenurus) has a protective value in the evolution of the family Columbidae. In this study, the complete mitogenome of T. sphenurus from Baise City, China, which represents the first sequenced species of the genus Treron in Tribe Treronini, is reported. This was accomplished using PCR-based methods and a primer-walking sequencing strategy with genus-specific primers. The mitogenome was found to be 18,919 bp in length comprising 37 genes, including 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and one control region. In terms of structure and composition, many similarities were found between the T. sphenurus and Hemiphaga novaeseelandiae (New Zealand pigeon) mitogenomes. This was further supported by phylogenetic analysis showing that T. sphenurus has a close evolutionary relationship with H. novaeseelandiae. The complete mitogenome of T. sphenurus reported here is expected to provide valuable molecular information for further studies on the phylogeny of the genus Treron and for analyses of the taxonomic status of the family Columbidae. [ABSTRACT FROM AUTHOR]

Fulfilling, he says, a request from monks abroad that he should write about St Antony, Athanasius did so, and two Latin translations of his Greek I Life i soon followed. Over 300 years later, Adomnán drew on Evagrius's I Life of Antony i in his I Life of Columba i . To the best of my knowledge, no-one has ever suggested that Adomnán read either, but the antithesis in the first, I in exordiis meritorum eius ... sequenti uita i , shows how readers of Evagrius or Adomnán might have expected the narrative to continue. [Extracted from the article]

Background: The turtle dove is a migratory species that has suffered a rapid decline principally across its Northern ranges, despite pronounced conservation measures. Consequently, it has been categorized as 'Near Threatened' in Europe. Degradation of breeding habitats and a decrease in food resources are listed as principal causes of this decline. Despite its importance, the productivity of the North African population is widely unknown. Here we present the first estimation of the density of the breeding population and the superior reproductively of Streptopelia turtur arenicola in Morocco and entire North Africa. Methods: This study was carried out for two seasons 2018-2019 in the Saïss plain, central Morocco. Based on previous data, doves were monitored weekly, from early March to late August, in aquatic ecosystems (two dams and one river) and farmlands (cereals and orchards). The breeding population was censused using the "pointcount" method, following a walked transect of 5 km in orchards, 7 km in cereal fields, and 3 km along the river. Equally, nests were searched in natural habitats counting riparian trees, forests, and ornamental trees, and in orchards based on the Common Birds Census (CBC) methodology, in which the singing doves, mating pairs, nesting, and/or feeding behavior were the most monitored signs to discover nests. In orchards, nests were searched line-by-line based on the rows of fruit trees. For each recorded nest, we note the breeding chronology, clutch size and incubation period, success and failure factors, dimensions, and vertical placement on trees. To evaluate the predictors of doves' occurrence, we noted at each site the presence of cereals, water, human disturbance, presence of nesting trees, and predators. Results and Discussion: In total, 3,580 turtle doves (22.37 birds/ha), including 240 breeding pairs, were documented. Nesting occurred mainly in olive groves, cereals were used for forage, and aquatic ecosystems for water sources. The nesting period lasted from late April to July (last fledglings). All nests were located on olive trees at a height of 225.30 ± 48.87 cm. The clutch size was 1.98 ± 0.13 (laid eggs/built nests), the incubation period lasted 14.16 ± 1.32 days, and the rearing period lasted 16.54 ± 1.76 days. The breeding success among the 240 monitored nests accounted for 73.84% during the nesting phase and 87.42% during the incubation phase; 71.5%% of nestlings have fledged, which is the highest success rate for turtle doves in Europe and Northwest Africa. Clutches were aborted mostly due to predation from snakes (7.5% of nests, 16.12% of eggs, and 5.63% of chicks), nest desertion (9.16% of nests and 5.37% of eggs), and marginally by the destruction of nests through farming activities. These findings are important for conservation plans, to restore turtle doves' habitats in Europe, where the species is widely declining. [ABSTRACT FROM AUTHOR]

Copyright of Ornitologia Colombiana is the property of Asociacion Colombiana de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Davidia involucrata is a significant living fossil with high abiotic stress tolerance. Although heat shock protein 20 (HSP20) has already been linked to heat stress, nothing is known about HSP20 family protein activities in D. involucrata. The functional dynamics of the D. involucrata HSP20 (DiHSP20) gene family were identified and characterized using a thorough genome-wide investigation. From the genome of D. involucrata, a total of 42 HSP20 genes were identified, which are distributed across 16 chromosomes. The DiHSP20 proteins were grouped into seven separate subfamilies by our phylogenetic analysis, which was validated by the conserved motif composition and gene structure studies. Segmental duplication events were shown to play a crucial role in the expansion of the DiHSP20 gene family. Synteny analysis revealed that 19 DiHSP20 genes of D. involucrata shared a syntenic connection with Arabidopsis genes, 39 with C. acuminata genes, and just 6 with O. sativa genes. Additionally, heat stress differently enhanced the expression levels of D. involucrata HSP20 genes. After 1 hour of heat treatment, the expression levels of most DiHSP20 genes, particularly DiHSP20-7, DiHSP20-29, DiHSP20-30, DiHSP20-32, and DiHSP20-34, were dramatically increased, suggestted that they might be employed as heat tolerance candidate genes. Overall, these findings add to our knowledge of the HSP20 family genes and provide helpful information for breeding heat stress resistance in D. involucrata. [ABSTRACT FROM AUTHOR]

Urbanization influences food quality and availability for many avian species, with increased access to human refuse and food subsidies in built environments. In relation to such nutritional intakes and their presumed impact on microbes harbored in the intestinal tract and metabolic profiles of host physiological systems, our overall knowledge of the role of gut microbiome (GM) and metabolomic expression in the avian host lags far behind our understanding of mammals. Therefore, the objective of this investigation was to examine the potential differential effect of an urban modeled versus control (i.e., bird seed) diet on the GM, the metabolic profiles of plasma, liver, adipose, kidney, and muscle tissues, and circulating endotoxin and inflammatory factors in urban-caught mourning doves (Zenaida macroura). We hypothesized that the urban diet would differently impact the profiles of the GM and tissue metabolomes and increase plasma lipopolysaccharide (LPS) and proinflammatory factors compared with animals fed a seed diet. After a 4- wk-diet period, contents of the large intestine were sequenced to profile the microbiome, metabolomic analyses were performed on plasma and tissue homogenates, and circulating LPS and inflammatory markers were assessed. The composition of the GM was significantly dissimilar between diets, with greater abundance of Erysipelatoclostridiaceae, Sanguibacteraceae, Oribacterium, and Sanguibacter and decreased circulating LPS in the urban-fed birds. These differences were largely not reflected in the surveyed metabolomes and plasma inflammatory markers. This research supports the notion that the microbial composition in urban doves is impacted by diet, though may only weakly associate with host physiology. [ABSTRACT FROM AUTHOR]

Enteropathies are a serious concern in racing pigeons as they significantly impair performance in races and their training, and viruses are suspected to be one of the main factors. Astroviruses are well-known to be responsible for causing enteric disease in humans and various other animals including birds, although their prevalence and pathogenicity in pigeons is poorly understood. In this study, we investigated 2 groups of young racing pigeons (sick—study group and healthy—control group) to assess the correlation between the number of astrovirus genome copies in cloacal swabs and the occurrence of enteropathy. To determine this, we developed a novel TaqMan quantitative PCR (qPCR) and digital droplet PCR (ddPCR) methods for astrovirus detection and absolute quantitative analysis. We also performed high-throughput sequencing to obtain the complete genome sequences and establish the genetic similarity of the obtained strains to known astroviruses of poultry and other avian species. Two new complete genome sequences of pigeon astroviruses in the Avastrovirus genus were identified, representing 2 new species. These were found most closely related to astroviruses identified in Columbidae species and chickens. They share an average of 75.8% genome-wide pairwise identity and 57.6% and 64.6% capsid protein sequence identity with other unclassified columbid avastrovirus sequences in GenBank. Although the difference in prevalence of astrovirus in the study and control group was found statistically insignificant, there was a significant difference between the number of genome copies in positive samples from both groups. These unambiguous results leave the role of astroviruses as enteropathogenic factors in pigeons still undetermined. [ABSTRACT FROM AUTHOR]

We've shown that pigeons can integrate separately acquired spatial maps into a cognitive map. Integration requires an element shared between maps. In two experiments using a spatial-search task in pigeons, we test spatial combination rules when no shared element was present during training. In all three experiments, pigeons first learned individual landmark-target maps. In subsequent tests involving combinations of landmarks, we found evidence that landmarks collaborate in guiding spatial choice at test (Experiment 1). In Experiment 2, pigeons were trained on two landmarks with different proximities to the target. On tests on a compound of both landmarks, pigeons showed stronger spatial control by the more proximal landmark, a performance overshadowing effect. Extinction of the proximal landmark shifted spatial control to the non-extinguished distal landmark. This reveals that the performance overshadowing effect was associative in nature, and not due to perceptual or spatial biases. This emphasis on spatial control during performance reflects the emphasis on performance processes that were a major focus in Ralph Miller's lab.

Registramos dos casos de leucismo en la paloma de collar Asiática (Streptopelia decaocto) en dos localidades del norte de México. Ambos individuos fueron los primeros registros de leucismo en esta especie para los estados de Nuevo León y Durango. Los dos ejemplares presentaban la mayor parte del cuerpo con plumaje blanco, patas rosadas y pico grisáceo (comparado con los individuos normales), pero mantuvieron los ojos con su color característico. Ambos individuos fueron observados solo una vez y en solitario.

Animals defend themselves against parasites in many ways. Defenses, such as physiological immune responses, are capable of clearing some infections. External parasites that do not feed on blood, however, are not controlled by the physiological immune system. Instead, ectoparasites like feather-feeding lice (Phthiraptera: Ischnocera) are primarily controlled by behavioral defenses such as preening. Here we test the hypothesis that birds able to preen are capable of clearing infestations of feather lice. We experimentally manipulated preening ability in a captive population of rock pigeons (Columba livia) that were infested with identical numbers of feather lice (Columbicola columbae or Campanulotes compar or both). We then monitored the feather louse infestations for 42 wk. Birds with impaired preening remained infested throughout the experiment; in contrast, the prevalence of lice on birds that could preen normally decreased by 50%. These data indicate that it is indeed possible for birds to clear themselves of feather lice, and perhaps other ectoparasites, by preening. We note, however, that captive birds spend more time preening than wild birds, and that they are less likely to be reinfested than wild birds. Thus, additional studies are necessary to determine under what circumstances wild birds can clear themselves of ectoparasites by preening. [ABSTRACT FROM AUTHOR]

Ectoparasitic fauna of 397 conveniently sampled domestic birds consisting of 213 chickens, 128 turkeys, 21 ducks, 19 guinea fowls, 8 pigeons and 8 geese were investigated in Maiduguri, Borno State. A total of one hundred and fifty-two 152 (38.29%) birds were infested with one ectoparasitic species or the other comprising of 115 (54.00%) chickens, 33 (25.78%) turkeys, 1 (5.26%) guinea fowl and 3 (37.50%) pigeons. No infestation was encountered among geese and ducks examined. The infestation rate differed significantly based on sex and age (p<0.05), but not the management system. Similarly, the occurrence varied significantly (p<0.05) based on locations of sampling (p<0.00001) and species of poultry examined (p<0.000049). Furthermore, 116 (29.21%) of the total birds examined had a single infestation with either louse, tick or mite species, while 36(9.06%) birds had mixed infestation with species from two or more of these ectoparasitic groups. Among the parasites encountered, lice present on 146 (36.77%) birds were the most prevalent, followed by mites 28(7.05%) and ticks 15(3.78%). Nine different species of ectoparasites belonging to the orders Mallophaga and Acarina were identified in the study. Menopon gallinae, Lipeurus caponis, Menacanthus stramineus, Goniodes gigas, Goniocotes gallinae and Columbicola columbae were the lice identified, while Cnemidocoptes mutans and Ornithonyssus bursa were the only species of mite identified. The poultry tick, Argas persicus was the only tick species found. Conclusively, the study revealed a high but variable burden of ectoparasitic infestation among poultry species examined, and that ectoparasites are common in minor poultry species as they do occur in chickens under different management systems in the study area. The need to investigate the diverse effects of ectoparasitism on the different poultry species is suggested here. [ABSTRACT FROM AUTHOR]

Sex ratio is an important parameter influencing the demography of wildlife species. Sex ratios are categorized as primary (sex at fertilization), secondary (sex at birth through immaturity), tertiary (sex at adulthood), and quaternary (sex at post-reproductive age). Herein, we examined the secondary1 (hatchling), secondary2 (juvenile or subadult), and tertiary (adult) sex ratios of white-winged doves (Zenaida asiatica). Also, because white-winged doves typically hatch two eggs, we also evaluated the secondary sex ratio of co-occurring nestlings. Interestingly, secondary and juvenile sex ratios were significantly male biased, whereas tertiary sex ratios were not biased. Additionally, the ratio of same-sex nestlings was also male biased. The lack of bias at the tertiary level supports Fisher's principle that differential selection for sex ratios of 1:1 exist and lead to more stable populations. Therefore, we conclude that there is some selection mechanism present in this species that selects against males reaching adult status given our findings at the secondary and juvenile sex ratio levels. La proporción de sexos es un parámetro importante que influye en la demografía de las especies silvestres. Las proporciones de sexos se clasifican en primarias (sexo en la fecundación), secundarias (sexo al nacer/inmaduro), terciarias (sexo en la edad adulta) y cuaternarias (sexo en la edad pos reproductiva). Aquí, examinamos la secundaria1 (cría), secundaria2 (juveniles o subadultos) y terciarios (adultos) de las palomas aliblancas (Zenaida asiatica). Además, debido a que las palomas aliblancas suelen incubar dos huevos, también evaluamos la proporción de sexos secundarios de los polluelos coexistentes. Curiosamente, las proporciones de sexos secundarios y de juveniles fueron significativamente sesgadas por los machos, mientras que las proporciones de sexos en el terciario no lo fueron. Además, la proporción de polluelos del mismo sexo también estaba sesgada por los machos. La falta de sesgo en la proporción terciaria apoya al principio de Fisher, que existe la selección diferencial para la proporción de sexo de 1:1 y conducen a poblaciones más estables. Por lo tanto, llegamos a la conclusión de que existe algún mecanismo de selección presente en esta especie que selecciona para que los machos no alcancen el estado adulto, dados nuestros hallazgos en la proporción de sexos secundaria y de juveniles. [ABSTRACT FROM AUTHOR]

Avian metaavulavirus 2 (AMAV-2) previously known as the avian paramyxovirus-2 causes mild to severe respiratory disease, reduced hatchability and infertility of eggs, including increase in white-shelled eggs in chickens and Turkey breeders. When exacerbated by secondary pathogens and environmental stresses, infection is more severe leading to significant economic losses. This study was conducted to determine, if any, the presence of antibodies to Avian metaavulavirus 2 (AMAV-2) in peri-domestic birds in Bauchi State, Nigeria. In all, one hundred sera samples from pigeons (n = 10) and doves (n = 90 were collected in Bauchi, Nigeria. Based on hemagglutination-inhibition (HI) test, overall seroprevalence of 27.0% (27/100) was recorded. In pigeon, the seroprevalence was 80.0% while 21.1% was recorded for dove with HI antibody titers ranging from 3log2 to 8log2. There was statistical significance obtained between dove and pigeon sera tested (p <.05). Until now and to the best of our knowledge, there are no reports on AMAV-2 in poultry or wild birds in Nigeria. This study, thus, provides preliminary information on AMAV-2 seroprevalence in Nigerian peri-domestic birds. The need to conduct further studies in other avian species and wild birds in Nigeria is highlighted. [ABSTRACT FROM AUTHOR]

Successful reproduction in avian species requires considerable parental care, and for most species the efforts of both parents are necessary for the survival of offspring. Here we make the case that in these species reproductive interactions are enhanced when neurochemical activity reinforces critical stimuli and behaviors through associative learning. Drawing from research on several different species, we describe evidence for the role of associative learning in the reproductive behaviors of ring neck doves (Streptopelia risoria). A hypothetical mechanism involving a combination of classical and operant conditioning is proposed to explain the formation and maintenance of the pair bond, nest fidelity, and incubation behavior. The role of the opiate system in reinforcing various aspects of reproductive behavior in this and other species is discussed. [ABSTRACT FROM AUTHOR]