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1.
Vet Res Commun ; 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39302550

ABSTRACT

This study reports a granulomatous hepatitis caused by Mycobacterium avium in an Atlantic yellow-nosed albatross (Thalassarche chlororhynchos) found dead on Brazil southern coast. At necropsy, the albatross was cachectic and the liver was severely enlarged with multifocal to coalescing white nodules. Histopathological evaluation revealed multifocal to coalescing granulomas with caseous necrosis, surrounded by an infiltrate of macrophages and multinucleated giant cells, and a thin capsule of fibrous connective tissue. The Fite-Faraco staining technique revealed multiple acid-fast bacilli (AFB) stained in magenta, predominantly in the areas of necrosis. Bacterial culture and polymerase chain reaction (PCR) analysis confirmed the presence of Mycobacterium avium in liver samples. This case underscores the importance of wildlife surveillance in coastal regions. Pelagic birds like the Atlantic yellow-nosed albatross can harbor pathogenic agents that represent a threat to wildlife and domestic animals. Enhanced monitoring and research are essential to understand the epidemiology and potential risks associated with such infections in coastal ecosystems.

2.
Mar Pollut Bull ; 207: 116805, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39128230

ABSTRACT

The Amazonian coastal ecosystems face a significant threat from plastic contamination, posing a major risk to their biodiversity. Here, we provide the first evidence of using plastics in nest building by Yellow-cacique Cacique (Cacicus cela) and Greater Kiskadee (Pitangus sulphuratus). During 2023 and 2024, 15 nests built with ropes and fishing lines were recorded in the Brazilian Amazon Coast, a colony of 12 nests in the State of Amapá and one nest in Pará for C. cela, and one nest for P. sulphuratus was observed in Maranhão during the fieldwork, covering all Brazilian Amazon Coast. These nests were observed on the edge of mangroves, built with solid waste from fishing activities, pointing out how environmental pollution can be incorporated into wildlife this issue. Our records emphasize the effect of plastic pollution on two passerine species associated with mangrove forests and the need for conservation measures and further research.


Subject(s)
Environmental Monitoring , Plastics , Animals , Brazil , Plastics/analysis , Nesting Behavior , Fisheries
3.
J Evol Biol ; 37(9): 1064-1075, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39044333

ABSTRACT

Prey often rely on multiple defences against predators, such as flight speed, attack deflection from vital body parts, or unpleasant taste, but our understanding on how often and why they are co-exhibited remains limited. Eudaminae skipper butterflies use fast flight and mechanical defences (hindwing tails), but whether they use other defences like unpalatability (consumption deterrence) and how these defences interact have not been assessed. We tested the palatability of 12 abundant Eudaminae species in Peru, using training and feeding experiments with domestic chicks. Further, we approximated the difficulty of capture based on flight speed and quantified it by wing loading. We performed phylogenetic regressions to find any association between multiple defences, body size, and habitat preference. We found a broad range of palatability in Eudaminae, within and among species. Contrary to current understanding, palatability was negatively correlated with wing loading, suggesting that faster butterflies tend to have lower palatability. The relative length of hindwing tails did not explain the level of butterfly palatability, showing that attack deflection and consumption deterrence are not mutually exclusive. Habitat preference (open or forested environments) did not explain the level of palatability either, although butterflies with high wing loading tended to occupy semi-closed or closed habitats. Finally, the level of unpalatability in Eudaminae is size dependent. Larger butterflies are less palatable, perhaps because of higher detectability/preference by predators. Altogether, our findings shed light on the contexts favouring the prevalence of single versus multiple defensive strategies in prey.


Subject(s)
Butterflies , Flight, Animal , Predatory Behavior , Animals , Butterflies/physiology , Peru , Tail/physiology , Wings, Animal/anatomy & histology , Phylogeny
4.
Glob Chang Biol ; 30(7): e17421, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39034889

ABSTRACT

Current knowledge about the impacts of urbanisation on bird assemblages is based on evidence from studies partly or wholly undertaken in the breeding season. In comparison, the non-breeding season remains little studied, despite the fact that winter conditions at higher latitudes are changing more rapidly than other seasons. During the non-breeding season, cities may attract or retain bird species because they offer milder conditions or better feeding opportunities than surrounding habitats. However, the range of climatic, ecological and anthropogenic mechanisms shaping different facets of urban bird diversity in the non-breeding season are poorly understood. We explored these mechanisms using structural equation modelling to assess how urbanisation affects the taxonomic, phylogenetic and functional diversity of avian assemblages sampled worldwide in the non-breeding season. We found that minimum temperature, elevation, urban area and city age played a critical role in determining taxonomic diversity while a range of factors-including productivity, precipitation, elevation, distance to coasts and rivers, socio-economic (as a proxy of human facilitation) and road density-each contributed to patterns of phylogenetic and functional diversity. The structure and function of urban bird assemblages appear to be predominantly shaped by temperature, productivity and city age, with effects of these factors differing across seasons. Our results underline the importance of considering multiple hypotheses, including seasonal effects, when evaluating the impacts of urbanisation on biodiversity.


Subject(s)
Biodiversity , Birds , Cities , Seasons , Urbanization , Animals , Birds/physiology , Phylogeny
5.
J Toxicol Environ Health A ; 87(17): 675-686, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38828979

ABSTRACT

The aviation sector is believed to be responsible for considerable environmental damage attributed to emission of a large number and amount of pollutants. Airports are often surrounded by forest fragments and humid areas that attract birds of prey and hence may potentially serve as useful bioindicators. The aim of the present study was to examine genotoxic potential in raptors exposed to airport pollution using the micronucleus (MN) test and morphological changes as evidenced by bilateral symmetry. This investigation was conducted at Salgado Filho International Airport of Porto Alegre - RS as well as in private and zoological breeding grounds. The presence of metals was measured in the blood cells of the collected birds. Seventeen birds (Caracara (Polyborus) plancus) were used in this study 11 from exposed and 6 from non-exposed group. The nuclear alterations clearly indicate that organisms exposed to airport pollution exhibited a significantly higher frequency of genetic damage compared to non-exposed birds. Further, manganese and chromium were detected exclusively in the blood of the exposed group. In contrast, the analysis of bilateral symmetry did not detect any significant morphologic differences between the two groups. Therefore, data indicate that blood genotoxic stress occurs in birds of prey living in civil aviation areas as evidenced by MN frequency increase and presence of manganese and chromium.


Subject(s)
Airports , Micronucleus Tests , Animals , Brazil , Environmental Monitoring , Micronuclei, Chromosome-Defective/chemically induced , DNA Damage , Cell Nucleus/drug effects , Raptors , Male
6.
Proc Biol Sci ; 291(2023): 20240866, 2024 May.
Article in English | MEDLINE | ID: mdl-38808444

ABSTRACT

Patterns of habitat use directly influence a species' fitness, yet for many species an individual's age can influence patterns of habitat use. However, in tropical rainforests, which host the greatest terrestrial species diversity, little is known about how age classes of different species use different adjacent habitats of varying quality. We use long-term mist net data from the Amazon rainforest to assess patterns of habitat use among adult, adolescent (teenage) and young understory birds in forest fragments, primary and secondary forest at the Biological Dynamics of Forest Fragments Project in Brazil. Insectivore adults were most common in primary forest, adolescents were equally likely in primary and secondary forest, and all ages were the least common in forest fragments. In contrast to insectivores, frugivores and omnivores showed no differences among all three habitat types. Our results illustrate potential ideal despotic distributions among breeding populations of some guilds of understory birds where adult insectivores may competitively exclude adolescent individuals from primary forest. Secondary forest recovery appears to hold promise as a breeding habitat for frugivore and omnivore species but only as a pre-breeding habitat for insectivores, but as the forest ages, the demographic structure of bird populations should match that of primary forest.


Subject(s)
Birds , Ecosystem , Rainforest , Animals , Birds/physiology , Brazil , Age Factors , Feeding Behavior
7.
Front Vet Sci ; 11: 1387040, 2024.
Article in English | MEDLINE | ID: mdl-38756514

ABSTRACT

Introduction: Highly pathogenic avian influenza A H5N1 clade 2.3.4.4b (hereafter H5N1) is causing vast impacts on biodiversity and poultry around the globe. In Chile, lethal H5N1 cases have been reported in a wide range of wild bird species, marine mammals, backyard and industrial poultry, and humans. This study describes the spatio-temporal patterns of the current epizootic of H5N1 in Chile and test drivers that could be associated with outbreak occurrence. Methods: We used H5N1 cases reported by the Chilean National Animal Health Authority from 5 December 2022 to 5 April 2023. These included wild bird cases confirmed through an avian influenza-specific real-time reverse transcription PCR assay (RT-qPCR), obtained from passive and active surveillance. Data were analyzed to detect the presence of H5N1 clusters under space-time permutation probability modeling, the association of H5N1 with distance and days since the first outbreak through linear regression, and the correlation of H5N1 presence with a number of ecological and anthropogenic variables using general linear modeling. Results: From 445 H5N1 identified outbreaks involving 613 individual cases in wild birds, a consistent wave-like spread of H5N1 from north to south was identified, which may help predict hotspots of outbreak risk. For instance, seven statistically significant clusters were identified in central and northern Chile, where poultry production and wildlife mortality are concentrated. The presence of outbreaks was correlated with landscape-scale variables, notably temperature range, bird richness, and human footprint. Discussion: In less than a year, H5N1 has been associated with the unusual mortality of >100,000 individuals of wild animals in Chile, mainly coastal birds and marine mammals. It is urgent that scientists, the poultry sector, local communities, and national health authorities co-design and implement science-based measures from a One Health perspective to avoid further H5N1 spillover from wildlife to domestic animals and humans, including rapid removal and proper disposal of wild dead animals and the closure of public areas (e.g., beaches) reporting high wildlife mortalities.

8.
New Phytol ; 243(1): 440-450, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38655668

ABSTRACT

Hybrid zones provide natural experimental settings to test hypotheses about species divergence. We concentrated on a hybrid swarm in which oil-collecting bees and flower-pecking birds act as pollinators of two Calceolaria species. We asked whether both pollinators contributed to flower divergence by differentially promoting prezygotic fitness at the phenotypic extremes that represent parentals. We studied pollinator-mediated selection on phenotypic traits critical in plant-pollinator mechanical interaction, namely plant height, reward-to-stigma distance, and flower shape. We utilised the quantity and quality of pollen deposited as fitness measures and distinguished between the contribution of the two pollinator types. Results showed uni- and bivariate disruptive selection for most traits through pollen grains deposited by both pollinators. Bird-mediated fitness favoured low plants with a long reward-to-stigma distance and a straight corolla, while bee-mediated fitness favoured tall plants with a short reward-to-stigma distance and curved corolla. In addition, stabilising selection at one end of the phenotypic range showed a bird-mediated reproductive asymmetry within the swarm. The disruptive pattern was countered, albeit weakly, by hybrids receiving higher-quality pollen on the stigmas. Results suggest that pollinator-mediated selection promotes divergence of integrated flower phenotypes mechanically adjusted either to bees or birds underscoring the importance of pollinator specialisation in diversification.


Subject(s)
Flowers , Genetic Fitness , Phenotype , Pollination , Selection, Genetic , Pollination/physiology , Animals , Bees/physiology , Flowers/physiology , Flowers/anatomy & histology , Birds/physiology , Pollen/physiology , Hybridization, Genetic , Species Specificity
9.
Animals (Basel) ; 14(8)2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38672354

ABSTRACT

Birds, including canaries and other birds, have become increasingly popular as pets. Bird fairs, where breeders gather and show their production in a championship setting, present a setting for possible Salmonella spp. contamination and transmission. Therefore, this study estimated the rate of Salmonella spp. isolation from cage papers, located in the bottom of cages of exotic pet birds, including canaries. Collected Salmonella isolates were used to determine the antimicrobial resistance profile to 52 antibiotics and 17 commercial disinfectants, based on pure or a mixture of acids, alcohols, aldehydes, alkalis, halogens, peroxygen, and quaternary ammonium compounds. The samples consisted of 774 cage papers taken in the 2015 Argentinean canary breeder championship, pooling three cage papers into one sterile sampling bag. Only one pool of the cage papers was positive for Salmonella spp. (0.4%), which belonged to the sample from three frill canary cages. Two strains of Salmonella serotype Glostrup were isolated, which were only resistant to sulfonamides and erythromycin and sensitive to alkali-based product PL301 AS. Although the rate of Salmonella spp. isolation from cage papers in an Argentinean canary breeder championship is low, it should not be discounted because Salmonella ser. Glostrup can be a source of human Salmonella outbreaks and they show high resistance to disinfecting products.

10.
Animals (Basel) ; 14(8)2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38672377

ABSTRACT

The study was conducted within a well-managed beef cattle operation in northeastern Mexico. Each nest was weighed and dissected to obtain the plant and animal material used to build the nests. The number of materials present per nest and relative frequency were determined. Twenty-one building materials were used. Over the years, Muhlenbergia torreyi represented 85.5% of the total biomass of the nests, and Aristida longiseta, Bouteloua gracilis, Brickellia canescens, Purshia mexicana and Cirsium ehrenbergii constituted 2.45, 2.80, 2.44, 1.34 and 1.11% of the total biomass, respectively. The above-mentioned grasses represented 95.62% of the total biomass. Material of animal origin was horse and cow hair, which represented 0.84 and 0.58% of the total biomass, respectively. It was concluded that, at the study site, Muhlenbergia torreyi was a key nest-building material for the Worthen sparrow nest.

11.
Rev. peru. biol. (Impr.) ; 31(2): e27481, abr.-jun 2024. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1576651

ABSTRACT

Resumen Reportamos seis nuevos casos de aves silvestres con aberración cromática provenientes de cuatro provincias de Ecuador. Los registros fotográficos provienen de observaciones oportunistas. El presente es el primer registro de plumaje aberrante para Anas bahamensis, Florisuga mellivora, Opisthocomus hoazín, Dendrocincla fuliginosa y Asemospiza obscura; mientras que se suman casos de individuos aberrantes en Turdus fuscater. El caso de F. mellivora es el más relevante por su rareza y evidencia patrones de coloración en la especie. Resaltamos la importancia de documentar y publicar el encuentro de estos eventos.


Abstract We report six new cases of wild birds with chromatic aberration from four provinces of Ecuador. The photographic records come from opportunistic observations. This is the first record of aberrant plumage for Anas bahamensis, Florisuga mellivora, Opisthocomus hoazín, Dendrocincla fuliginosa y Asemospiza obscura; while cases of aberrant individuals are added in Turdus fuscater. The case of F. mellivora is the most relevant due to its rarity and evidence of coloration patterns in the species. We highlight the importance of documenting and publishing the encounter of these events.

13.
Animals (Basel) ; 14(4)2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38396616

ABSTRACT

Urbanization is one of the more important phenomena affecting biodiversity in the Anthropocene. Some organisms can cope with urban challenges, and changes in birds' acoustic communication have been widely studied. Although changes in the timing of the daily organization of acoustic communication have been previously reported, there is a significant gap regarding possible variations in song structure between dawn and dusk choruses. Considering that urbanization imposes different soundscapes for dawn and dusk choruses, we postulate two hypotheses: (i) there are variations in song parameters between dawn and dusk choruses, and (ii) such parameters within the city will vary in response to urban noise. We studied urban and extra-urban populations of Chiguanco Thrush in La Paz, Bolivia, measuring in dawn and dusk choruses: song length; song sound pressure level; minimum, maximum, range and dominant frequency; and the number of songs per individual. The results support our two hypotheses: there were more songs, and songs were louder and had larger band widths at dawn than at dusk in urban and extra-urban populations. Urban Chiguanco Thrushes sing less, the frequency of the entire song rises, and the amplitude increases as compared with extra-urban Chiguanco Thrushes. Understanding variations between dawn and dusk choruses could allow for a better interpretation of how some bird species cope with urban challenges.

14.
Vet Parasitol Reg Stud Reports ; 48: 100981, 2024 02.
Article in English | MEDLINE | ID: mdl-38316508

ABSTRACT

Platynosomum spp. are parasites that inhabit the gallbladder and bile ducts of various mammals and birds worldwide. Most studies of Platynosomum spp. in birds focus on the observation and morphological characterization of the parasite through parasitological or molecular examinations, with scarce literature describing anatomopathological alterations, mainly histopathological. We report the case of a male barn owl infected with Platynosomum spp.. At necropsy, the barn owl showed dilation with parasites and fibrosis of the intrahepatic bile ducts and gallbladder. Microscopically, it was possible to identify trematodes in the bile ducts associated with a lymphoplasmacytic inflammatory infiltrate. The morphological structures of the worms were described on histopathology and direct examination. The presence of parasitism that is usually cosmopolitan in wild animals represents a risk to the biodiversity of fauna in the region, as well as a warning about the spread and maintenance of the biological cycle of the worm in humans and domestic animals.


Subject(s)
Dicrocoeliidae , Strigiformes , Trematoda , Trematode Infections , Humans , Male , Animals , Trematode Infections/diagnosis , Trematode Infections/epidemiology , Trematode Infections/veterinary , Brazil , Mammals
15.
Animals (Basel) ; 14(2)2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38254390

ABSTRACT

Induced pluripotent stem cells (iPSCs) were first generated by Yamanaka in 2006, revolutionizing research by overcoming limitations imposed by the use of embryonic stem cells. In terms of the conservation of endangered species, iPSC technology presents itself as a viable alternative for the manipulation of target genetics without compromising specimens. Although iPSCs have been successfully generated for various species, their application in nonmammalian species, particularly avian species, requires further in-depth investigation to cover the diversity of wild species at risk and their different protocol requirements. This study aims to provide an overview of the workflow for iPSC induction, comparing well-established protocols in humans and mice with the limited information available for avian species. Here, we discuss the somatic cell sources to be reprogrammed, genetic factors, delivery methods, enhancers, a brief history of achievements in avian iPSC derivation, the main approaches for iPSC characterization, and the future perspectives and challenges for the field. By examining the current protocols and state-of-the-art techniques employed in iPSC generation, we seek to contribute to the development of efficient and species-specific iPSC methodologies for at-risk avian species. The advancement of iPSC technology holds great promise for achieving in vitro germline competency and, consequently, addressing reproductive challenges in endangered species, providing valuable tools for basic research, bird genetic preservation and rescue, and the establishment of cryobanks for future conservation efforts.

16.
Emerg Infect Dis ; 30(3): 619-621, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38290826

ABSTRACT

We report 4 highly pathogenic avian influenza A(H5N1) clade 2.3.4.4.b viruses in samples collected during June 2023 from Royal terns and Cabot's terns in Brazil. Phylodynamic analysis revealed viral movement from Peru to Brazil, indicating a concerning spread of this clade along the Atlantic Americas migratory bird flyway.


Subject(s)
Charadriiformes , Influenza A Virus, H5N1 Subtype , Influenza in Birds , Influenza, Human , Animals , Humans , Influenza in Birds/epidemiology , Animals, Wild , Brazil/epidemiology , Birds , Phylogeny
17.
Anat Histol Embryol ; 53(1): e13011, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38230831

ABSTRACT

This study aimed to evaluate radiographic and sonographic features, and histogram parameters based on grayscale ultrasound of the liver and spleen in healthy toco toucans. Fifteen adult toco toucans (Ramphastos toco), seven females and eight males, weighing approximately 650 g, were enrolled in the study. On the right lateral radiographic view, the liver was visualized in the midventral region of the coelomic cavity; ultrasonographically, the liver was located in the middle portion of the coelomic cavity in close relationship to the heart, and thoracic and abdominal air sacs. Two hepatic lobes were identified; the right lobe was larger than the left one. The spleen was visualized in 10 toco toucans on radiographs and only in eight toucans on ultrasound exams. The gallbladder was identified only on ultrasound. On the right lateral radiographic view, the spleen was visualized dorsal to the proventriculus and ventral to the lungs/air sacs as an oval shape. Ultrasonographically, the spleen was observed caudal to the liver, cranial to the proventriculus and craniodorsal to the ventriculus. There was no significant difference in spleen length for either radiographic or ultrasound measurements. The brightness intensity (BI) for mean gray level (G) and standard deviation of gray levels (SG ) in the liver were 101.315 (± 16.170) and 12.453 (± 2.616), respectively. Mean G and SG levels in the spleen were 63.940 (± 18.321) and 7.494 (± 3.595), respectively. In conclusion, the sonographic features and histogram parameters indicated that the liver is more echogenic and heterogeneous than the spleen, which must be considered for diagnosing alterations in these organs.


Subject(s)
Abdomen , Spleen , Female , Male , Animals , Spleen/diagnostic imaging , Liver/diagnostic imaging , Ultrasonography/veterinary , Heart , Birds
18.
Rev. peru. biol. (Impr.) ; 31(1): e26729, Jan.-Mar. 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1565774

ABSTRACT

Abstract Beak deformity have a frequency of 0.5% in wild bird populations. In addition to being rare, beak deformities are also poorly reported in the Brazilian scientific literature. Here we report beak deformities in the species: Dendrocincla merula, Amazona ochrocephala and Pheugopedius genibarbis, all of which occurred in southwestern Brazilian Amazon. Dendrocolaptids make intensive use of their beaks in the search for insects and small vertebrates, where they explore in cracks in wood with lateral blows. In the case presented here, this behaviour may have been the cause of the breakage of the tip of this individual's maxilla. In Brazilian territory, few species of parrots were recorded with deformity in the beak and in the individual in this work, everything indicates that Amazona ochrocephala was a captive animal, as it was excessively thin and its diet probably had a low content of vitamins and calcium, where their deficiency even when the animal was a puppy may have contributed to the deformity of the maxilla. Cases of beak deformities in species of the Troglodytidae family are rare, but the individual in this work presented an unusual curvature in the maxilla not observed in other individuals in museum collections. Only with more reports will we be able to better understand the occurrence and causes of these beak deformities in wild birds.


Resumen La deformidad del pico es una característica rara y tiene una frecuencia baja, con 0.5% de casos en poblaciones de aves silvestres. Además de ser raras, las deformidades del pico también son escasamente reportadas en la literatura científica brasileña. Reportamos aquí deformidades en los picos de aves de las especies: Dendrocincla merula, Amazona ochrocephala y Pheugopedius genibarbis, en los cuales todos los registros ocurrieron en el sudoeste de la Amazonia brasileña. Los dendrocoláptidos hacen uso intensivo del pico en la búsqueda de insectos y pequeños vertebrados, explorando en grietas de la madera con golpes laterales. En el caso aquí presentado, este comportamiento de exploración pudo haber sido la causa de la rotura de la punta del maxilar de este individuo. En el territorio brasileño, pocas especies de loros fueron registradas con deformidad en el pico y en el individuo de este trabajo, todo indica que Amazona ochrocephala era un animal de cautiverio, ya que estaba excesivamente delgado y su dieta probablemente tenía un bajo contenido de vitaminas y calcio, donde su deficiencia incluso cuando el animal era un joven puede haber contribuido a la deformidad del maxilar. Los casos de deformidades del pico en especies de la familia Troglodytidae son raros, pero el individuo de este trabajo presentaba una curvatura inusual en el maxilar no observada en otros individuos de esta especie depositados en la colección científica. Sólo con más informes podremos entender mejor la ocurrencia y las causas de estas deformidades del pico en aves silvestres.

19.
Vet Res Commun ; 48(1): 607-613, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37815657

ABSTRACT

Monensin poisoning is uncommon and has been rarely reported in birds. This work aimed to described clinical-pathological aspects of an outbreak of monensin poisoning in captive and free-ranging birds. Thirty-seven of 600 captive birds fed a diet containing 893.19 mg/kg of monensin died within 10 days (mortality 6.17%). There was no ionophore antibiotics on the feed label supplied to captive birds, which established an error in feed production. Necropsies were performed on twelve animals: Muscovy duck (Cairina moschata) (2/12), greater rhea (Rhea americana) (2/12), black-necked swan (Cygnus melancoryphus) (2/12), garganey (Anas querquedula) (1/12), ostrich (Struthio camelus) (1/12), and common pigeon (Columbus livia) (4/12). These four common pigeons were free-ranging birds and died after eating the same contaminated feed. Birds were mainly found dead, however in animals which clinical signs were observed (Columba livia, Rhea americana, Cairina moschata, Anas querquedula, and Struthio camelus), they included incoordination, inability to stand, and intense prostration, that ranged from 24 to 72 h until death. Grossly, five birds had focally extensive pale firm areas in the myocardium and two had in the skeletal muscles, one being concomitant lesions. Histologically, muscle necrosis and degeneration were observed in striated musculature (skeletal and/or heart) in all birds analyzed. Monensin poisoning outbreaks can affect free-ranging birds that are fed on external feeders, as well as captive birds, due to an error in the feed formulation.


Subject(s)
Monensin , Muscular Diseases , Animals , Columbidae , Myocardium , Muscular Diseases/veterinary , Heart
20.
Anat Histol Embryol ; 53(1): e12987, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37850266

ABSTRACT

The common pauraque Nyctidromus albicollis (Gmelin, 1789) is a widespread avian species; however due to its nocturnal habits and reclusive behaviour, little is known about their vision and ecology. Most avian species are visually dependent with advanced visual systems providing high spatial resolution, on the species needs. Each ocular structure has a specific role in contributing towards high visual function, and the cornea is the first refractive structure in the visual process. However, the common pauraque cornea had not been described until the present data. Therefore, this study aims to describe the morphology and morphometry of the common pauraque cornea by means of light and scanning electron microscopy to evaluate the cross-sectional anatomy as well as the ultrastructure of the endothelial cells. Histological similarities with the cornea of other birds have been observed, but the thickness of the common pauraque cornea is much smaller than the other described corneas. A better understanding of the common pauraque cornea can help us better explain the physiology of vision and the visual requirements of this species. In turn, this will help us better understand how this species successfully interacts with its environment, and will improve our knowledge on how to interpret pathological changes in their cornea in a clinical setting.


Subject(s)
Endothelial Cells , Strigiformes , Animals , Microscopy, Electron, Scanning/veterinary , Cornea
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