Avian malaria in a feral-pet pigeon: a case report.

BACKGROUND: Avian malaria is caused by diverse parasite species of the genus Plasmodium, and it affects various bird species. The occurrence of this disease in some wild bird species is sparsely documented due to the scarce availability of samples. Hence the pathogenicity in some hosts is not completely known. In addition, feral birds may act as reservoirs bridging the transmission cycle from wild migratory birds to domestic and zoo-kept bird species. CASE PRESENTATION: An owner of pigeons adopted a feral pigeon (Columba livia forma domestica) and housed it together with his other pet-pigeons. The bird died unexpectedly a few weeks after a surgical procedure and necropsy revealed a severely anaemic carcass, with pale organs and hydropericardium. Histopathologic analysis revealed inflammatory infiltrates in the lung and liver, and monocytes and Kupffer cells contained haemozoin pigment indicative of phagocytosis of Plasmodium-infected erythrocytes. A high erythrocytic infection rate of 18% was evident in tissues and blood vessels in various organs. Furthermore, the thyroid had masses classified as thyroid carcinomas. Immunohistochemistry with anti- Plasmodium falciparum HSP70 antibody revealed positive signals in erythrocytes and intravascular leucocytes. Further microscopy analysis using a Hemacolor-stained impression smear revealed a high parasitaemia with an asynchronous infection showing all erythrocytic stages. Molecular diagnosis by PCR identified Plasmodium relictum, lineage GRW11 as the aetiological agent. The bird presented died most likely due to an acute infection as evidenced by the high blood parasitaemia, leading to major erythrocyte destruction. Further analyses of feral pigeons (n = 22) did not reveal any additional cases of Plasmodium infections. CONCLUSION: This study reports the first mortality associated with P. relictum lineage GRW11. The study supports previous studies, suggesting that Plasmodium infections are not frequent in pigeons. Host conditions like immunosuppression due to the tumour may have influenced the infection outcome in this fatal case. Use of anti-P. falciparum HSP70 antibody for detection of P. relictum antigens for immune assays in blood and tissue samples will be a useful tool for future studies.

Phylogenetic analysis, genetic diversity, and epidemiology of pigeon paramyxovirus type 1 in China.

Pigeon paramyxovirus type 1 (PPMV-1) poses significant economic challenges to the pigeon industry in China. However, information about the prevalence, genetic diversity, and epidemiology of PPMV-1 in China is still lacking. In this study, we isolated six strains of PPMV-1 from Hubei and Zhejiang provinces in 2022. All six isolates were found to belong to subgenotype VI.2.1.1.2.2. Five of them were identified as mesogenic and one as lentogenic. Multiple mutations were observed in the F and HN proteins of these isolates. Comprehensive analysis of global PPMV-1 strains highlighted the dominance of genotype VI, showing that VI.2.1.1.2.2 has been the dominant subgenotype since 2011. We also identified 36 host-specific amino acid substitutions that are unique to PPMV-1 in comparison to chicken-origin NDVs. The data reported here contribute to our understanding of the epidemiology, genetic diversity, and prevalence of PPMV-1 and serve as a valuable reference for the prevention and control of PPMV-1.

The problem with two-event sequence learning by pigeons.

Bonobos appear to show little evidence of learning to make one response (R1) to an AB sequence and a different response (R2) to sequences BB, AA, and BA (Lind et al. PLoS ONE 18(9):e0290546, 2023), yet under different conditions, pigeons can learn this (Weisman et al. Exp Psychol Anim Behav Process 6(4):312, 1980). Aspects of the bonobo procedure may have contributed to this failure. Most important, no response was required in the presence of the stimuli to encourage attention to them. Furthermore, learning to make one response to the target sequence and another to the other sequences involves a bias that allows for better than chance responding. With the two-alternative forced-choice procedure used with the bonobos, the R1 response is correct for one sequence, whereas the R2 response is correct for three sequences. To correct for this, there are three times as many AB trials as each of the other sequences. However, this correction allows a bias to develop in which reinforcement often can be obtained by using only the last stimulus seen as the basis of choice (e.g., when the last stimulus is B respond R1 when the last stimulus is A respond R2). This solution yields reinforcement on five out of six, or 83%, of the trials. In the present experiment with pigeons, using this two-alternative forced choice procedure, most subjects tended to base their choice on the last-seen stimulus. This design allowed subjects to use a suboptimal but relatively effective choice strategy.

Molecular identification and biological characterization of Eimeria columbarum from domestic pigeons (Columba livia domestica) in Guangdong, China.

Pigeon coccidiosis caused by Eimeria spp. is an important veterinary disease with a significant economic impact on the pigeon industry. Preventive measures for Eimeria columbarum in pigeons have been hampered by the lack of extensive genetic, morphological, and biological data on the oocysts. In this study, we examined the prevalence and identity of Eimeria spp. in domestic pigeons from seven cities in Guangdong Province, China. Data show that coccidiosis was prevalent in domestic pigeons in Guangdong Province, with an overall Eimeria spp. detection rate of 73.4%. Five Eimeria species were identified, including E. columbarum (73.4%), Eimeria kapotei (25.6%), Eimeria labbeana (19.6%), Eimeria duculai (19.6%), and Eimeria tropicalis (6.7%). We obtained single oocyst-derived lines of the dominant E. columbarum from fecal specimens. E. columbarum oocysts measured 20.06 ± 0.69 µm × 18.63 ± 1.03 µm, and sporocysts measured 10.29 ± 0.82 µm × 85.38 ± 0.46 µm. In infection experiment using obtained E. columbarum isolates, 60-day-old coccidia-free pigeons exhibited a prepatent period of 105 h and patent period of 9-10 days followed by severe diarrhea, depression, anorexia, and emaciation. Endogenous development of the parasite was observed mainly in the cytoplasm of epithelial cells in the duodenum, jejunum, ileum, and rectum. Two generations of meronts developed on days 3 and 4 after infection, respectively, while gamont and gamete developed on day 5 after infection. The morphological, genetic, and biological data are expected to be useful in elucidating the biological characterization of pigeon coccidiosis to develop measures against the treatment and containment of this disease.

Evolution and biological characteristics of H11 avian influenza viruses isolated from migratory birds and pigeons.

The emergence of novel avian influenza reassortants in wild birds in recent years is a public health concern. However, the viruses that circulate in migratory birds are not fully understood. In this study, we summarized and categorized global H11 avian influenza viruses and reported that waterfowl and shorebirds are the major reservoirs of the identified H11 viruses. The surveillance data of the 35,749 faecal samples collected from wild bird habitats in eastern China over the past seven years revealed a low prevalence of H11 viruses in birds, with a positive rate of 0.067% (24 isolates). The phylogenetic analysis of the twenty viruses indicated that H11 viruses have undergone complex reassortment with viruses circulating in waterfowl and shorebirds. These tested viruses do not acquire mammalian adaptive mutations in their genomes and preferentially bind to avian-type receptors. Experimental infection studies demonstrated that the two tested H11N9 viruses of wild bird origin replicated and transmitted more efficiently in ducks than in chickens, whereas the pigeon H11N2 virus isolated from a live poultry market was more adapted to replicate in chickens than in ducks. In addition, some H11 isolates replicated efficiently in mice and caused body weight loss but were not lethal. Our study revealed the role of waterfowl and shorebirds in the ecology and evolution of H11 viruses and the potential risk of introducing circulating H11 viruses into ducks or chickens, further emphasizing the importance of avian influenza surveillance at the interface of migratory birds and poultry.

Investigation of Glandula Uropygialis in Different Avian Species Using Morphometric and Histological Methods.

The aim of this study was to identify the glandula uropygialis's macroanatomical and histological structure in male and female birds (stork, goose, eagle, pigeon, crow and sparrowhawk) that belong to different populations. A total of 58 specimens were used in the study. The study materials were delivered to our laboratory by nature conservation and national parks, and no animals were euthanised for this study. The longitudinal and transversal lengths, dorsoventral heights and feather length of the glandula uropygialis and papilla uropygialis were measured with a digital calliper. Haematoxylin-eosin and Masson trichrome staining were performed for histological examinations. The shape of the glandula uropygialis was found to be pear-shaped in pigeons and sparrowhawks, heart-shaped in geese, kidney-shaped in eagles and oval-fascule-shaped in storks. In the crow, the shape of the glandula uropygialis was different from the other species in that it was located dorso-caudally. Histomorphological examination of the glands of these species revealed that the gland generally consisted of two lobes, right and left, surrounded by connective tissue from the outside. The parenchyma of these lobes consisted of tubulo-alveolar secretory glands with a radial arrangement from the periphery to the centre. The glands within the lobes differed from the periphery to the centre and although the general histomorphological appearance was similar between bird species, some differences were observed between species. Similar stromal structure was observed in all bird species evaluated in the study. However, the reticular connective tissue forming the roof of the gland was found to be more developed in pigeons, especially in Masson's trichroma staining. The degenerative layer in the glands was more prominent in the eagle, followed by the goose and crow. Although a common general histological structure was observed among bird species, simple histomorphological differences were found between these formations, but no differences were found between the sexes. The results obtained will be compared with the findings of the aves class and will provide a data source for this special gland specific to birds. It is thought that the results obtained may help to determine the functional properties of the gland and contribute to the science of ornithology.

A new glycoprotein from pigeon egg: Study on its structure and digestive characteristics.

Pigeon egg white (PEW) is widely recognized as a promising source of bioactive proteins, with a high degree of glycosylation. This study focused on the characterization of a novel glycoprotein extracted from PEW, known as ovalbumin-related protein Y (OVAY). Our investigation included an analysis of the N-glycan and protein structures of OVAY, as well as an examination of simulated gastrointestinal digestive products and the transmembrane transport mechanism of OVAY-digested peptides. The results revealed that OVAY contains two glycosylation sites (Asn 62, 215) and consists of 30 N-linked glycoforms, with the top three glycans being N6H3, N6H7S1, and N6H5. Additionally, OVAY is rich in Gal and sialic acid and exhibits a rod-like molecular structure. Furthermore, it was found that OVAY demonstrates resistance to gastric digestion, with its digested peptides primarily transported via PepT1 and endocytosis. This study provides insight into the glycoprotein structure of OVAY and elucidates its physiological activity, providing a theoretical reference for the development of a novel sialate-rich protein.

[Three-dimensional positioning and trajectory tracking of pigeons in large indoor spaces].

Animal localization and trajectory tracking are of great value for the study of brain spatial cognition and navigation neural mechanisms. However, traditional optical lens video positioning techniques are limited in their scope due to factors such as camera perspective. For pigeons with excellent spatial cognition and navigation abilities, based on the beacon positioning technology, a three-dimensional (3D) trajectory positioning and tracking method suitable for large indoor spaces was proposed, and the corresponding positioning principle and hardware structure were provided. The results of in vitro and in vivo experiments showed that the system could achieve centimeter-level positioning and trajectory tracking of pigeons in a space of 360 cm × 200 cm × 245 cm. Compared with traditional optical lens video positioning techniques, this system has the advantages of large space, high precision, and high response speed. It not only helps to study the neural mechanisms of pigeon 3D spatial cognition and navigation, but also has high reference value for trajectory tracking of other animals.

Pathological and immunohistochemical studies of lymphoid leukosis in pigeons in Egypt.

Background: Pigeon leukosis is primarily caused by avian leukosis virus subgroup A (ALV-A). It infects and transforms lymphoid cells, leading to the development of tumors in various lymphoid tissues and other organs especially the liver. Aim: This study was conducted to diagnose lymphoid leukosis in a naturally infected pigeon flock in Egypt. Methods: Tissue specimens from the liver, spleen, thymus, kidney, lung, proventriculus, gizzard, intestine, pancreas, heart, pectoral muscle, ovary, and testes were collected from infected birds for pathological and immunohistochemical examinations. Results: Clinical signs were generally nonspecific and comprised weakness, dehydration, and emaciation. Gross lesions were mostly in the liver and spleen, in the form of minute white nodules scattered on the liver surface. Microscopic examination of the liver, spleen, and kidneys showed masses of uniform sizes and the presence of differentiated lymphoid cells. These cells appeared as large mononuclear cells with poorly defined cell membranes. Immunohistochemical investigation exhibited that the ALV-A positive indicators were chiefly accessible in the liver, ovary, spleen, and kidney. Conclusion: Lymphoid leukosis in pigeons could be provisionally diagnosed by a pathological picture of characteristic tumors and confirmed by immunoreactivity of viral antigens in different tissues.

Phylogenetic position of the pigeon mite, Ornithonyssus sylviarum, with amplification of its immunogenetic biomarkers in Egypt.

Ornithonyssus sylviarum (O. sylviarum) is an obligatory, blood-sucking ectoparasite widely distributed among poultry and other mammals, causing significant economic losses. This study represented the first report of molecular genotypic identification of O. sylviarum from pigeons, Columba livia domestica, in Egypt. PCR and sequencing of the 28S rRNA gene were conducted. The resulting mite sequences were subjected to BLAST analysis, revealing 90-100% similarity to O. sylviarum in all tested samples. The sequences were deposited in GenBank under the accession numbers PP049086 and PP033720. A phylogenetic tree was constructed to compare the obtained species with related species worldwide. Additionally, infected pigeons showed increased expression of IL-1, IL-10, IFN-γ, and TGF-ß3 genes and elevated serum levels of stress biomarkers. The increased level of these cytokines indicates there was a disturbance in the immune status of the infected host with parasite compared with control healthy ones. This increases the susceptibility to infection with other pathogens.

Molecular detection and characterization of Trichomonas gallinae isolated from ornamental birds in Tehran, Iran.

Trichomonas gallinae is a widespread protozoan parasite that primarily affects birds, causing a disease known as avian trichomonosis. The present study aimed to investigate the prevalence and genetic diversity of T. gallinae, a parasite causing avian trichomoniasis in feral pigeons, budgerigars, and finches in Tehran, Iran. The 5.8S ribosomal RNA locus, along with the internal transcribed spacer 2 (ITS2) region, has been extensively utilized for genotype identification and for determining inter- and intra-specific diversity. More recently, the Fe-hydrogenase (Fe-Hyd) gene has been suggested as an additional genetic marker to enhance the accuracy of strain subtyping discrimination. In the present study, a total of 12% (12/100) birds examined were infected with T. gallinae using microscopy and PCR methods. Infection was found in seven of 30 (23.3%) feral pigeons, three of 40 (7.5%) budgerigars, and two of 30 (6.66%) finches. Analysis of the ITS2 region of T. gallinae isolates revealed two highly similar sequences. The first sequence (GenBank: OQ689964-OQ689970) was found in five feral pigeons and two budgerigars, whereas the second sequence (GenBank: OQ689971-OQ689975) was identified in two feral pigeons, one budgerigar, and two finches. Phylogenetic analysis confirmed the presence of two distinct clusters (cluster I and cluster II) within the trichomonads based on the ITS2 region. However, further analysis using Fe-Hyd revealed greater diversity, with three subtypes identified (A1, A2, and C1). One isolate identified in the present study (GenBank accession number: OQ694508.1) belonged to subtype A1. Combining ITS2 and Fe-Hyd markers holds promise for a more comprehensive understanding of the population structure of T. gallinae and the potential role of ITS2 in host adaptation.

Fine-scale tracking reveals visual field use for predator detection and escape in collective foraging of pigeon flocks.

During collective vigilance, it is commonly assumed that individual animals compromise their feeding time to be vigilant against predators, benefiting the entire group. One notable issue with this assumption concerns the unclear nature of predator 'detection', particularly in terms of vision. It remains uncertain how a vigilant individual utilizes its high-acuity vision (such as the fovea) to detect a predator cue and subsequently guide individual and collective escape responses. Using fine-scale motion-capture technologies, we tracked the head and body orientations of pigeons (hence reconstructed their visual fields and foveal projections) foraging in a flock during simulated predator attacks. Pigeons used their fovea to inspect predator cues. Earlier foveation on a predator cue was linked to preceding behaviors related to vigilance and feeding, such as head-up or down positions, head-scanning, and food-pecking. Moreover, earlier foveation predicted earlier evasion flights at both the individual and collective levels. However, we also found that relatively long delay between their foveation and escape responses in individuals obscured the relationship between these two responses. While our results largely support the existing assumptions about vigilance, they also underscore the importance of considering vision and addressing the disparity between detection and escape responses in future research.

Most animals have to compromise between spending time foraging for food and other resources and keeping careful watch for approaching predators or other threats. Many are thought to address this trade-off by living in a group where they rely on the vigilance of others to free up more time for foraging. If one individual animal detects a threat, they alert the whole group so that every individual can respond. However, it remains unclear how individuals use vision to detect a threat and how they communicate the threat to the rest of the group. Pigeons are a useful animal model to address this question because they tend to live in groups and their vision is well understood. A pit at the back of their eye called the fovea is responsible for building clear, detailed images of the centre of the field of vision. When pigeons attend to something of interest, they typically direct their gaze by moving their whole head instead of moving their eyes, making head orientation a good proxy for researchers to track where they are looking. To better understand how pigeons detect potential threats and communicate them to the rest of the flock, Delacoux and Kano used motion capture technology to track the head movements of groups of pigeons. To encourage the pigeons to forage, grain was scattered in the centre of an enclosed room. A plastic sparrowhawk (representing a potential predator) would then emerge and move across the room before disappearing again. Analysis of the imaging data revealed that pigeons use their fovea to spot predators. Individuals that were looking around before the potential predator emerged directed their fovea towards it more quickly than pigeons that were eating. These pigeons also took flight more quickly, and this likely triggered the rest of the group to follow. Due to improvements in the tracking technologies, these findings may help scientists understand in finer detail how animals in a group detect and respond to threats and other cues in their environment. Therefore, the experimental approach used by Delacoux and Kano could also be used to investigate how information is passed among groups of other animal species.

Anatomical, histological, and scanning electron microscopic features of the esophagus and crop in young and adult domestic pigeons (Columba livia Domestica).

BACKGROUND: Pigeons (Columba livia) are mainly raised as a source of animal protein, racing, leisure and as an experimental animal. The present study investigated the morphology of the esophagus in the young and adult domestic pigeon, Columba livia domestica. METHODS: Ten young and ten adult, normal, and healthy pigeons were collected from the local breeders. Samples from different parts of esophagus and crop were examined grossly, by stereomicroscopy, scanning and light microscopy. RESULTS: The esophagus consisted of a long cervical part, a crop, and a short thoracic part. The crop was represented by a thin-walled outpouching with two lateral diverticula. The mucosa presented wavy fine folds in the cervical esophagus, irregular folds in the lateral diverticula giving it a corrugated appearance, and prominent longitudinal folds with several gland openings in the middle and lower parts of the crop, as well as in the thoracic esophagus. The density of gland openings was higher in adult pigeons than that in young pigeons. The mucosa of the esophagus was lined by non-keratinized stratified squamous epithelium. The shape, height, and branching of the mucosal folds differed between young and adult pigeons. Mucous-secreting alveoli were detected in the middle part of the crop as well as in the thoracic esophagus, but not in the cervical esophagus or lateral diverticula of the crop. CONCLUSION: The variations between the young and adult pigeons suggest a functional adaptation of adult pigeons to their diet compared to young pigeons.

Innovative molecular and immunological approaches of heterophyiasis infecting some Egyptian marketed fishes.

Heterophyiasis is a highly endemic disease in the Nile Delta, Egypt, where people consume raw or undercooked Oreochromis niloticus and Mugil cephalus. Birds and rats play a crucial role in fish-borne zoonotic trematode transmission since they serve as natural and experimental hosts. This study aimed to update the epidemiological information, morphological description, molecular identification and gene expression of two distinct heterophyid metacercariae in Giza, Wadi Al-Rayan, and Lake Manzala, Egypt, whereas various heterophyid infections could be expected. The present Centrocestus formosanus, Heterophyes heterophyes, and Heterophyes nocens with accession numbers OR947651.1, OR947700.1, and OR947719.1, respectively, matched with those recorded in the GenBank. Findings of the current investigation indicated that various cytokines like IL-1ß, MHC-II, and TNF-α rapidly elevated in the infected pigeon's intestines. Additionally, the infection expanded due to the parasite's ejection from the host and the host's clinical affliction, which induced humoral immune responses. Interestingly, investigation of other trematode species is in extreme demand in terms of zoonoses. We suggest controlling snails, managing migratory birds, and examining and frying fishes to the point when the encysted metacercariae is destroyed.

Virulence and host specificity of staphylococci from Staphylococcus intermedius group of pigeon origin with an emphasis on Staphylococcus intermedius.

The Staphylococcus intermedius group (SIG) includes coagulase-positive staphylococci commonly found in animals. The taxonomic classification within the SIG has evolved with molecular techniques distinguishing five species. Despite their similarities, these species exhibit varied host affinities, with unclear implications for virulence and host interaction. This study aimed to investigate the presence of coagulase-positive staphylococci in pigeons and to detect genes encoding for selected virulence factors in isolated strains. Another goal was to determine the adhesion capabilities of randomly selected pigeon S. intermedius, S. delphini, and canine S. pseudintermedius strains to canine and pigeon corneocytes and their adhesion and invasion abilities to canine keratinocytes in vitro. In total, 121 coagulase-positive strains were isolated from domestic and feral pigeons. The most prevalent species were S. delphini B and S. intermedius in domestic and feral pigeons, respectively. We proved that pigeon strains carried genes encoding for exfoliative toxin SIET and leukotoxin Luk-I. Moreover, we found that S. intermedius showed higher adherence to pigeon than to canine corneocytes, aligning with its presumed natural host. No difference in adherence abilities of S. pseudintermedius to canine and pigeon corneocytes was observed. In this study, we also observed that S. pseudintermedius could successfully invade the canine keratinocytes, in contrary to S. delphini and S. intermedius. Moreover, only S. intermedius was not able to invade canine keratinocytes at all. These findings highlight the complex interplay between SIG bacteria, and their hosts, underscoring the need for further research to understand the mechanisms of host adaptation and pathogenicity within this group.

Medetomidine-vatinoxan-midazolam provides similar sedation depth with reduced bradycardia compared to dexmedetomidine-midazolam in pigeons (Columba livia domestica).

OBJECTIVE: To determine if sedation with medetomidine-vatinoxan (Zenalpha; Dechra Veterinary Products) and midazolam (Alvogen) (ZM) would cause less cardiovascular depression and maintain similar depth and duration of sedation in pigeons (Columba livia domestica) compared to dexmedetomidine and midazolam (DM). METHODS: In a blinded crossover study, 15 healthy adult domestic pigeons were sedated IM with either dexmedetomidine (0.08 mg/kg) and midazolam (2 mg/kg) or medetomidine (0.16 mg/kg), vatinoxan (3.2 mg/kg), and midazolam (2 mg/kg) from November through December 2023. Each subject was monitored for 60 minutes, then the sedation was reversed with atipamezole (0.8 mg/kg) and flumazenil (0.1 mg/kg) as needed. Sedation scores, heart rates, and respiratory rates were compared. RESULTS: There was no significant difference in the peak sedation score between DM and ZM groups, with both exhibiting median scores of 4 (heavy sedation). Mean heart rate was significantly higher for ZM than DM at 5, 10, 20, 30, 45, 60, and 65 minutes postinjection. Bradycardia occurred in both groups at 5 and 10 minutes postinjection and persisted for DM until reversal with atipamezole. Arrhythmias were auscultated in both groups. Bradypnea was not observed in either group, and all birds resumed normal behavior following recovery and the following day. CONCLUSIONS: Medetomidine-vatinoxan-midazolam provides a similar depth of sedation to DM but with less incidence of bradycardia. Further study is needed to determine the clinical applicability of this sedative in birds. CLINICAL RELEVANCE: Medetomidine-vatinoxan may be considered for short-term sedation and restraint in cardiovascularly stable pigeons.

In vitro antibacterial activity of danofloxacin against Escherichia coli isolated from pigeons and its pharmacokinetic in pigeons.

This experiment aimed to investigate the in vitro antimicrobial activity of danofloxacin against Escherichia coli (E. coli) isolated from pigeons, as well as the pharmacokinetics of danofloxacin in pigeons following oral (PO), intramuscular (IM), and intravenous (IV) administration. The minimum inhibitory concentration (MIC) of danofloxacin was first determined for 38 clinical E. coli strains using the micro broth dilution method. Subsequently, 30 healthy pigeons were weighed and randomly divided into 3 groups: IM, IV, and PO, with 10 pigeons in each group. Danofloxacin was given at 5 mg/kg body weight (BW) through 3 different routes. Blood was collected, and plasma was separated at various time points from 0 to 48 h. Plasma samples were analyzed for danofloxacin concentrations using a validated HPLC method. Pharmacokinetic analysis was performed using Phoenix software and a noncompartmental analytical (NCA) method. The results indicated that danofloxacin had a strong antibacterial effect on E. coli, with a MIC50 of 0.5 µg/mL. The noncompartmental analysis showed that after PO and IM administration at 5 mg/kg in pigeons, peak plasma concentrations (Cmax) of 0.61 and 1.62 µg/mL were reached at 4.5 and 0.53 h, respectively. The oral and intramuscular bioavailability (F) were 68.08% ± 24.82% and 87.82% ± 25.36%, respectively. Following IV administration, danofloxacin was widely distributed in pigeons, with volume of distribution (VZ) and volume of distribution at steady state (VSS) values of 6.11 ± 2.01 and 4.65 ± 1.62 L/kg, respectively, and was eliminated slowly, with an elimination half-life (t1/2λz) of 6.41 ± 2.15 h. Based on the calculated ratio values of AUC/MIC, the current IV, IM, and PO doses of 5 mg/kg of danofloxacin would be expected to effectively treat pigeons infected with E. coli strains with MIC values equal to or less than 0.5 µg/mL.

Research Note: Study on the in-situ preservation of pigeons based on the level of endangerment of genetic resources.

The large-scale and intensive development of the meat pigeon breeding industry have resulted in the replacement of a large number of low-performance local breeds by a few breeds with excellent production performance. However, due to the characteristics of pigeon species that are monogamous, for which the W chromosome cannot be recovered and for which semen cannot be cryopreserved, the preservation of pigeon species is still mainly based on in-situ preservation. In this study, pigeons were classified into 6 classes of endangerment based on the criteria of the 100-year inbreeding coefficient of poultry populations in the "Assessment of Endangered Poultry Genetic Resources" (NY/T 2996-2016). The results show that when the generation interval was 1.5 yr, the number of ideal populations with the same gene frequency variance or the same heterozygosity decay rate of pigeons in class 1 to 5 was ≤149, 150 to 204, 205 to 316, 317 to 649 and ≥650. In random-reserved breeding, when the generation interval was 1.5 yr, the number of male (female) pigeons corresponding to class 1 to 5 was ≤74, 75 to 102, 103 to 157, 158 to 324 and ≥325. In family-equal-reserved breeding, when the generation interval was 1.5 yr, the number of male (female) pigeons corresponding to class 1 to 5 was ≤36, 37 to 50, 51 to 78, 79 to 162 and ≥163. When the generation interval was 1.5 yr, the inbreeding increments corresponding to class 1 to 5 were ≥0.00335, 0.00244 to 0.00334, 0.00159 to 0.00243, 0.00078 to 0.00158 and ≤0.00077; with the same population size, the inbreeding coefficient and inbreeding increment decreased with the increase of generation interval; the population effective content, inbreeding coefficient and inbreeding increment of family-equal-reserved pigeons were lower than those of random-reserved pigeons. The results of this study have certain reference value for analyzing the status quo of local and endangered species, constructing live gene banks and breeding farms of poultry genetic resources, and rescuing endangered species.

Characteristics of changes in volatile organic compounds and bacterial communities in physically preserved pigeon breast meat.

To understand the relationship between changes in aroma and bacteria in pigeon breast meat (PBM) during preservation, bacterial communities and volatile compounds in PBM were analyzed using high-throughput sequencing and gas chromatography-ion mobility spectrometry. Analyses of total viable bacteria counts revealed that modified atmospheric packaging (MAP) and electron beam irradiation (EBI) could be used to extend the shelf-life of PBM to 10 d and 15 d, respectively. Furthermore, Lactococcus spp. and Psychrobacter spp. were the dominant bacterial genera of the MAP and EBI groups, respectively. The results of the study revealed 91 volatile organic compounds, one of which, butanal, was the most intense volatile organic compound while being an important source of aroma differences between the physical preservation techniques. Alpha-terpinolene, acetoin-M, gamma-butyrolactone, 1-hexanol-M, and 2,6-dimethyl-4-heptanone may be markers of PBM spoilage. During preservation, the MA group (treatment with 50 % CO2 + 50 % N2) demonstrated greater stabilization of PBM aroma. A Spearman correlation analysis showed that Lactococcus spp., Psychrobacter spp., and Pseudomonas spp. were the dominant bacterial genera of PBM during preservation and were closely related to an increase in the intensity of anisole, 2-methyl-3-furanthiol, and 5-methyl-2-furanmethanol, respectively. Lactococcus spp. and Psychrobacter spp. play crucial roles in the sensory degradation of PBM. In this study, we analyzed the changes in bacterial genera and volatile organic compounds of PBM under different physical preservation techniques to identify a suitable method for preserving PBM and evaluating its freshness.

Geometric morphometric analysis of beak shape of Columbimorphae (Columbas, Van, Mardin and Dönek).

Selective breeding over centuries has led to the emergence of numerous pigeon breeds from the single species Columba livia, showcasing unparalleled phenotypic diversity. In Eastern Turkey, Van pigeons originate, while Tumbler pigeon varieties thrive countrywide, reflecting local traditions. The avian beak, vital for survival, offers insights into domestication and traits influenced by natural selection. Geometric morphometrics, a shape analysis method, allows for a comprehensive examination of beak shapes among domestic pigeons, providing a nuanced understanding of their complexity. Understanding beak diversity in pigeons, especially those found in Turkey, enhances our knowledge of avian evolution and adaptation processes. The study utilized 48 skulls from 4 pigeon breeds, including wild rock pigeons and domestic pigeons of Tumbler, Mardin and Van breeds, all free from pathological lesions and adults. Geometric morphometric analyses of beak shape were conducted using dorsal and lateral photographs, with landmarks placed using tpsDig software. MorphoJ software facilitated procrustes analysis and principal component analysis (PCA) to assess morphological variability and differentiate pigeon breeds based on shape patterns, with significance set at p < 0.05. PCA revealed significant shape variations among pigeon breeds, with 47 principal components identified for lateral beak views and 36 principal components for dorsal views. Canonical variates analysis further distinguished morphological patterns among breeds, indicating distinct shape variations in both dorsal and lateral views, elucidating the unique characteristics of each breed's beak morphology. Our results demonstrate statistically significant differences in pigeon beak shape, particularly in the lateral view, confirming the importance of these variations (p < 0.05) and suggesting that such differences occur less than 5% of the time under the null hypothesis.