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1.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204472

RESUMO

The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration.


Assuntos
Lactonas/isolamento & purificação , Lactonas/farmacologia , Struthioniformes/metabolismo , Administração Oral , Administração Tópica , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Diclofenaco/administração & dosagem , Diclofenaco/farmacologia , Edema/tratamento farmacológico , Emulsões/farmacologia , Formaldeído/efeitos adversos , Ibuprofeno/administração & dosagem , Ibuprofeno/farmacologia , Masculino , Paleógnatas/metabolismo , Ratos , Ratos Wistar , Pele/efeitos dos fármacos
2.
Zootaxa ; 4951(2): zootaxa.4951.2.6, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33903405

RESUMO

The nine currently recognized subspecies in the Brown Tinamou (Crypturellus obsoletus) complex are disjunctly widespread in South America, and at least three of them occur in Brazil. Morphological diagnosis of most of these taxa is imprecise, in contrast with consistent vocal differences described in the literature. We conducted a taxonomic review of two Amazonian taxa, C. o. griseiventris and C. o. hypochraceus, using morphological, morphometric, and vocal characters. Our results indicate that C. o. hypochraceus (Miranda-Ribeiro, 1938) is a junior synonym of C. o. griseiventris (Salvadori, 1895), and that Crypturellus griseiventris (Salvadori, 1895) must be treated as a full species, based on unique and fully diagnosable plumage and vocal patterns.


Assuntos
Paleógnatas , Animais , Aves , Classificação , Paleógnatas/classificação , Filogenia
3.
PLoS Comput Biol ; 17(4): e1008843, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33793558

RESUMO

The arrangement and physiology of muscle fibres can strongly influence musculoskeletal function and whole-organismal performance. However, experimental investigation of muscle function during in vivo activity is typically limited to relatively few muscles in a given system. Computational models and simulations of the musculoskeletal system can partly overcome these limitations, by exploring the dynamics of muscles, tendons and other tissues in a robust and quantitative fashion. Here, a high-fidelity, 26-degree-of-freedom musculoskeletal model was developed of the hindlimb of a small ground bird, the elegant-crested tinamou (Eudromia elegans, ~550 g), including all the major muscles of the limb (36 actuators per leg). The model was integrated with biplanar fluoroscopy (XROMM) and forceplate data for walking and running, where dynamic optimization was used to estimate muscle excitations and fibre length changes throughout both gaits. Following this, a series of static simulations over the total range of physiological limb postures were performed, to circumscribe the bounds of possible variation in fibre length. During gait, fibre lengths for all muscles remained between 0.5 to 1.21 times optimal fibre length, but operated mostly on the ascending limb and plateau of the active force-length curve, a result that parallels previous experimental findings for birds, humans and other species. However, the ranges of fibre length varied considerably among individual muscles, especially when considered across the total possible range of joint excursion. Net length change of muscle-tendon units was mostly less than optimal fibre length, sometimes markedly so, suggesting that approaches that use muscle-tendon length change to estimate optimal fibre length in extinct species are likely underestimating this important parameter for many muscles. The results of this study clarify and broaden understanding of muscle function in extant animals, and can help refine approaches used to study extinct species.


Assuntos
Simulação por Computador , Extinção Biológica , Membro Posterior/fisiologia , Locomoção , Modelos Biológicos , Fibras Musculares Esqueléticas/fisiologia , Paleógnatas/fisiologia , Algoritmos , Animais , Fenômenos Biomecânicos , Membro Posterior/anatomia & histologia , Tendões/fisiologia
4.
Parasit Vectors ; 14(1): 85, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509249

RESUMO

BACKGROUND: Numerous laboratory and fewer field-based studies have found that ixodid ticks develop more quickly and survive better at temperatures between 18 °C and 26 °C and relative humidity (RH) between 75 and 94%. Ixodes anatis Chilton, 1904, is an endophilic, nidicolous species endemic to North Island brown kiwi (Apteryx mantelli) (NIBK) and the tokoeka (Apteryx australis), and little is known about the environmental conditions required for its development. The aims of this study were to determine and compare the conditions of temperature and RH that ensure the best survival of the kiwi tick and the shortest interstadial periods, in laboratory conditions and outdoors inside artificial kiwi burrows. METHODS: Free-walking engorged ticks were collected off wild kiwi hosts and placed in the laboratory under various fixed temperature and humidity regimes. In addition, sets of the collected ticks at different developmental stages were placed in artificial kiwi burrows. In both settings, we recorded the times taken for the ticks to moult to the next stage. RESULTS: Larvae and nymphs both showed optimum development at between 10 °C and 20 °C, which is lower than the optimum temperature for development in many other species of ixodid ticks. However, larvae moulted quicker and survived better when saturation deficits were < 1-2 mmHg (RH > 94%); in comparison, the optimum saturation deficits for nymph development were 1-10 mmHg. CONCLUSIONS: Our results suggest that the kiwi tick has adapted to the stable, but relatively cool and humid conditions in kiwi burrows, reflecting the evolutionary consequences of its association with the kiwi.


Assuntos
Ixodes , Paleógnatas/parasitologia , Animais , Temperatura Baixa , Interações Hospedeiro-Parasita , Umidade , Ixodes/crescimento & desenvolvimento , Ixodes/fisiologia , Laboratórios , Estágios do Ciclo de Vida , Muda , Nova Zelândia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Estações do Ano , Temperatura
5.
Parasitology ; 148(1): 1-30, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33070787

RESUMO

Toxoplasma gondii infections are common in humans and animals worldwide. Wild and domestic avian species are important in the epidemiology of T. gondii infections because felids prey on them and excrete millions of oocysts in the environment, disseminating the infection. Herbivorous birds are also excellent sentinels of environmental contamination with T. gondii oocysts because they feed on the ground. Toxoplasma gondii infections in birds of prey reflect infections in intermediate hosts. Humans can become infected by consuming undercooked avian tissues. Here, the authors reviewed prevalence, persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from turkeys, geese, ducks, ratites and avian species (excluding chickens) worldwide 2009-2020. Genetic diversity of 102 T. gondii DNA samples isolated worldwide is discussed. The role of migratory birds in dissemination of T. gondii infection is discussed.


Assuntos
Aves/parasitologia , Toxoplasma , Toxoplasmose Animal/epidemiologia , Migração Animal , Animais , Animais Selvagens/parasitologia , Doenças das Aves/epidemiologia , Galinhas/parasitologia , DNA de Protozoário , Reservatórios de Doenças/parasitologia , Patos/parasitologia , Variação Genética , Humanos , Oocistos , Paleógnatas/parasitologia , Prevalência , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Perus/parasitologia
6.
Anat Rec (Hoboken) ; 304(3): 461-479, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32558300

RESUMO

Extant cassowaries (Casuarius) are unique flightless birds found in the tropics of Indo-Australia. They have garnered substantial attention from anatomists with focus centered on the bony makeup and function of their conspicuous cranial casques, located dorsally above the orbits and neurocranium. The osteological patterning of the casque has been formally described previously; however, there are differing interpretations between authors. These variable descriptions suggest that an anatomical understanding of casque anatomy and its constituent elements may be enhanced by developmental studies aimed at further elucidating this bizarre structure. In the present study, we clarify casque osteology of the southern cassowary (C. casuarius) by detailing casque anatomy across an extensive growth series for the first time. We used micro-computed tomography (µCT) imaging to visualize embryonic development and post-hatching ontogeny through adulthood. We also sampled closely related emus (Dromaius novaehollandiae) and ostriches (Struthio camelus) to provide valuable comparative context. We found that southern cassowary casques are comprised of three paired (i.e., nasals, lacrimals, frontals) and two unpaired elements (i.e., mesethmoid, median casque element). Although lacrimals have rarely been considered as casque elements, the contribution to the casque structure was evident in µCT images. The median casque element has often been cited as a portion of the mesethmoid. However, through comparisons between immature C. casuarius and D. novaehollandiae, we document the median casque element as a distinct unit from the mesethmoid.


Assuntos
Paleógnatas/anatomia & histologia , Crânio/anatomia & histologia , Animais , Austrália , Osteologia , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
7.
BMC Genomics ; 21(1): 874, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287726

RESUMO

BACKGROUND: Bird mitogenomes differ from other vertebrates in gene rearrangement. The most common avian gene order, identified first in Gallus gallus, is considered ancestral for all Aves. However, other rearrangements including a duplicated control region and neighboring genes have been reported in many representatives of avian orders. The repeated regions can be easily overlooked due to inappropriate DNA amplification or genome sequencing. This raises a question about the actual prevalence of mitogenomic duplications and the validity of the current view on the avian mitogenome evolution. In this context, Palaeognathae is especially interesting because is sister to all other living birds, i.e. Neognathae. So far, a unique duplicated region has been found in one palaeognath mitogenome, that of Eudromia elegans. RESULTS: Therefore, we applied an appropriate PCR strategy to look for omitted duplications in other palaeognaths. The analyses revealed the duplicated control regions with adjacent genes in Crypturellus, Rhea and Struthio as well as ND6 pseudogene in three moas. The copies are very similar and were subjected to concerted evolution. Mapping the presence and absence of duplication onto the Palaeognathae phylogeny indicates that the duplication was an ancestral state for this avian group. This feature was inherited by early diverged lineages and lost two times in others. Comparison of incongruent phylogenetic trees based on mitochondrial and nuclear sequences showed that two variants of mitogenomes could exist in the evolution of palaeognaths. Data collected for other avian mitogenomes revealed that the last common ancestor of all birds and early diverging lineages of Neoaves could also possess the mitogenomic duplication. CONCLUSIONS: The duplicated control regions with adjacent genes are more common in avian mitochondrial genomes than it was previously thought. These two regions could increase effectiveness of replication and transcription as well as the number of replicating mitogenomes per organelle. In consequence, energy production by mitochondria may be also more efficient. However, further physiological and molecular analyses are necessary to assess the potential selective advantages of the mitogenome duplications.


Assuntos
Genoma Mitocondrial , Paleógnatas , Animais , Aves/genética , Evolução Molecular , Rearranjo Gênico , Filogenia
8.
Parasitol Res ; 119(12): 4287-4290, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33043419

RESUMO

Coccidia (Eimeria spp.) in brown kiwi (Apteryx mantelli) cause significant morbidity and mortality in captive rearing facilities. Monitoring the abundance of this parasite in individual birds is crucial for successful management of kiwi. This research compares the abilities of centrifugal faecal flotations (CFF) and a modified Mini-FLOTAC protocol to detect oocysts. We hypothesised that the Mini-FLOTAC would detect higher oocyst counts. Kiwi dropping samples (n = 10) were homogenized in MgSO4 (SG 1.28) and oocyst counts made with CFFs and Mini-FLOTAC counting chambers, with three replicates for each method. For CFF, 0.5 g of droppings were examined using standard methods. Mini-FLOTAC counts were made using a modified sample preparation compared with the manufacturer's protocol but still used a 1:20 dilution of droppings. Oocysts were quantified using light microscopy at ×100-300 magnification. A linear mixed-effects model by REML showed that oocyst per gram estimates via the Mini-FLOTAC method were 3.2 times higher (95% CI 2.4-4.5, p < 0.01) than the CFF results. This increased detection likely represents a more accurate estimation of parasite shedding and should be considered for use in research or applications requiring more accuracy, cost-effectiveness, or accessibility than the CFF provides.


Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Eimeria/fisiologia , Paleógnatas/parasitologia , Contagem de Ovos de Parasitas/veterinária , Animais , Coccidiose/parasitologia , Fezes/parasitologia , Oocistos/fisiologia , Contagem de Ovos de Parasitas/métodos , Manejo de Espécimes
9.
Genes (Basel) ; 11(10)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007827

RESUMO

The hallmark of sex chromosome evolution is the progressive suppression of recombination which leads to subsequent degeneration of the non-recombining chromosome. In birds, species belonging to the two major clades, Palaeognathae (including tinamous and flightless ratites) and Neognathae (all remaining birds), show distinctive patterns of sex chromosome degeneration. Birds are female heterogametic, in which females have a Z and a W chromosome. In Neognathae, the highly-degenerated W chromosome seems to have followed the expected trajectory of sex chromosome evolution. In contrast, among Palaeognathae, sex chromosomes of ratite birds are largely recombining. The underlying reason for maintenance of recombination between sex chromosomes in ratites is not clear. Degeneration of the W chromosome might have halted or slowed down due to a multitude of reasons ranging from selective processes, such as a less pronounced effect of sexually antagonistic selection, to neutral processes, such as a slower rate of molecular evolution in ratites. The production of genome assemblies and gene expression data for species of Palaeognathae has made it possible, during recent years, to have a closer look at their sex chromosome evolution. Here, we critically evaluate the understanding of the maintenance of recombination in ratites in light of the current data. We conclude by highlighting certain aspects of sex chromosome evolution in ratites that require further research and can potentially increase power for the inference of the unique history of sex chromosome evolution in this lineage of birds.


Assuntos
Paleógnatas/genética , Cromossomos Sexuais/genética , Animais , Eucromatina , Evolução Molecular , Feminino , Heterocromatina , Masculino , Filogenia , Recombinação Genética , Seleção Genética , Cromatina Sexual , Cromossomos Sexuais/fisiologia
10.
Biol Reprod ; 102(6): 1261-1269, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32179898

RESUMO

Aromatase (P450arom, CYP19A1) is the terminal enzyme in the synthesis of the steroid hormone family of estrogens. Not surprisingly, this enzyme has structural similarities between the limited number of species studied thus far. This study examined the structure of aromatases from four diverse Australian species including a marsupial (tammar wallaby; Macropus eugenii), monotreme (platypus; Ornithorhynchus anatinus), ratite (emu; Dromaius novaehollandiae) and lizard (bearded dragon; Pogona vitticeps). We successfully built homology models for each species, using the only crystallographically determined structure available, human aromatase. The amino acid sequences showed high amino acid sequence identity to the human aromatase: wallaby 81%, platypus 73%, emu 75% and bearded dragon at 74%. The overall structure was highly conserved among the five species, although there were non-secondary structures (loops and bends) that were variable and flexible that may result in some differences in catalytic activity. At the N-terminal regions, there were deletions and variations that suggest that functional distinctions may be found. We found that the active sites of all these proteins were identical, except for a slight variation in the emu. The electrostatic potential across the surfaces of these aromatases highlighted likely variations to the protein-protein interactions of these enzymes with both redox partner cytochrome P450 reductase and possibly homodimerization in the case of the platypus, which has been postulated for the human aromatase enzyme. Given the high natural selection pressures on reproductive strategies, the relatively high degree of conservation of aromatase sequence and structure across species suggests that there is biochemically very little scope for changes to have evolved without the loss of enzyme activity.


Assuntos
Aromatase/metabolismo , Lagartos/metabolismo , Marsupiais/metabolismo , Paleógnatas/metabolismo , Ornitorrinco/metabolismo , Sequência de Aminoácidos , Animais , Aromatase/genética , Regulação Enzimológica da Expressão Gênica , Genoma , Humanos , Lagartos/genética , Marsupiais/genética , Modelos Moleculares , Paleógnatas/genética , Ornitorrinco/genética , Conformação Proteica , Especificidade da Espécie
11.
Proc Biol Sci ; 287(1921): 20193005, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32070251

RESUMO

Tinamous host the highest generic diversity of lice of any group of birds, as well as hosting representatives of all four avian feather louse ecomorphs. Although the generic diversity of tinamou feather lice is well documented, few attempts have been made to reconstruct the phylogenetic relationships among these lice. To test whether tinamou feather lice form a monophyletic group as a whole, we used whole-genome sequencing to estimate a higher-level phylogeny of tinamou feather lice, together with a broad diversity of other avian feather louse groups. In total, we analysed sequences from over 1000 genes for 48 genera of avian lice using both concatenated and coalescent approaches to estimate the phylogeny of this diverse group of avian feather lice. Although the body louse ecomorph of tinamou feather lice formed a monophyletic group, they did not strictly form a monophyletic group together with the other three ecomorphs of tinamou feather lice. In particular, a clade comprised of several feather louse genera, mainly from South America, is nested phylogenetically within tinamou lice, which also have their main centre of diversity in South America. These results suggest in situ radiation of these parasites in South America.


Assuntos
Paleógnatas/parasitologia , Animais , Evolução Biológica , Aves/parasitologia , Plumas/parasitologia , Interações Hospedeiro-Parasita , Ftirápteros , Filogenia , América do Sul
12.
Trop Anim Health Prod ; 52(1): 243-247, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31313019

RESUMO

This study was carried out to estimate genetic parameters for morphology, body weight, and tonic immobility traits in the red-winged tinamou (Rhynchotus rufescens). Information on 690 birds was used and genetic parameters were estimated using Bayesian methods under a multi-trait animal model. The following traits were considered in this study: tarsal length (TL), bill length (BL), wing length (WL), head width (HW), bill width (BW), mature weight (MW), weight at 90 days (W90), and tonic immobility (TI). The heritability showed estimates between 0.15 for wing length and 0.56 for bill length. Positive and negative genetic correlations were estimated, ranging from - 0.33 to 0.81. All the morphological, production, and behavioral traits studied will have moderate to high response to selection. The body weight at 90 days is a better alternative for use in breeding programs and its selection would not lead to an increase in the time of tonic immobility. Both the selection for weight gain and for reduction of tonic immobility time would lead to an increase in the size of the legs of the red-winged tinamou, which could be advantageous for thermal control of these birds in tropical systems.


Assuntos
Peso Corporal/genética , Resposta de Imobilidade Tônica , Paleógnatas/genética , Animais , Cruzamento , Hereditariedade , Paleógnatas/anatomia & histologia , Paleógnatas/fisiologia
13.
Anat Rec (Hoboken) ; 303(4): 1035-1042, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31313482

RESUMO

Lithornithids are volant stem palaeognaths from the Paleocene-Eocene. Except for these taxa and the extant neotropical tinamous, all other known extinct and extant palaeognaths are flightless. Investigation of properties of the lithornithid wing and its implications for inference of flight style informs understood locomotor diversity within Palaeognathae and may have implications for estimation of ancestral traits in the clade. Qualitative comparisons with their closest extant volant relatives, the burst-flying tinamous, previously revealed skeletal differences suggesting lithornithids were capable of sustained flight, but quantitative work on wing morphology have been lacking. Until comparatively recently, specimens of lithornithids preserving wing feather remains have been limited. Here, we reconstruct the wing of an exceptionally preserved specimen of the Early Eocene lithornithid Calciavis grandei and estimate body mass, wing surface area, and wing span. We then estimate flight parameters and compare our estimates with representatives from across Aves in a statistical framework. We predict that flight in C. grandei was likely marked by continuous flapping, and that lithornithids were capable of sustained flight and migratory behavior. Our results are consistent with previous hypotheses that the ancestor of extant Palaeognathae may also have been capable of sustained flight. Anat Rec, 303:1035-1042, 2020. © 2019 Wiley Periodicals, Inc.


Assuntos
Voo Animal/fisiologia , Paleógnatas/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Evolução Biológica , Fósseis , Paleógnatas/fisiologia , Filogenia , Asas de Animais/fisiologia
14.
BMC Evol Biol ; 19(1): 233, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881941

RESUMO

BACKGROUND: Palaeognathae is a basal clade within Aves and include the large and flightless ratites and the smaller, volant tinamous. Although much research has been conducted on various aspects of palaeognath morphology, ecology, and evolutionary history, there are still areas which require investigation. This study aimed to fill gaps in our knowledge of the Southern Cassowary, Casuarius casuarius, for which information on the skeletal systems of the syrinx, hyoid and larynx is lacking - despite these structures having been recognised as performing key functional roles associated with vocalisation, respiration and feeding. Previous research into the syrinx and hyoid have also indicated these structures to be valuable for determining evolutionary relationships among neognath taxa, and thus suggest they would also be informative for palaeognath phylogenetic analyses, which still exhibits strong conflict between morphological and molecular trees. RESULTS: The morphology of the syrinx, hyoid and larynx of C. casuarius is described from CT scans. The syrinx is of the simple tracheo-bronchial syrinx type, lacking specialised elements such as the pessulus; the hyoid is relatively short with longer ceratobranchials compared to epibranchials; and the larynx is comprised of entirely cartilaginous, standard avian anatomical elements including a concave, basin-like cricoid and fused cricoid wings. As in the larynx, both the syrinx and hyoid lack ossification and all three structures were most similar to Dromaius. We documented substantial variation across palaeognaths in the skeletal character states of the syrinx, hyoid, and larynx, using both the literature and novel observations (e.g. of C. casuarius). Notably, new synapomorphies linking Dinornithiformes and Tinamidae are identified, consistent with the molecular evidence for this clade. These shared morphological character traits include the ossification of the cricoid and arytenoid cartilages, and an additional cranial character, the articulation between the maxillary process of the nasal and the maxilla. CONCLUSION: Syrinx, hyoid and larynx characters of palaeognaths display greater concordance with molecular trees than do other morphological traits. These structures might therefore be less prone to homoplasy related to flightlessness and gigantism, compared to typical morphological traits emphasised in previous phylogenetic studies.


Assuntos
Laringe/anatomia & histologia , Paleógnatas/anatomia & histologia , Paleógnatas/genética , Filogenia , Animais , Evolução Biológica , Feminino , Glote/anatomia & histologia , Masculino , Orofaringe/anatomia & histologia , Paleógnatas/classificação , Vocalização Animal
15.
J Parasitol ; 105(5): 733-737, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31584862

RESUMO

The prevalence of anti-Toxoplasma gondii antibodies was investigated among 104 ratites: 68 rheas (Rhea americana), 16 emus (Dromaius novaehollandiae), and 20 ostriches (Struthio camelus) in 4 Brazilian states. The prevalence in rheas was 26.5% (18 of 68), and titers were 1:100 (n = 8), 1:200 (n = 1), 1:400 (n = 4), 1:800 (n = 4), and 1:1,600 (n = 1). In emus, the prevalence was 50% (8 of 16), and titers were 1:50 (n = 1) and 1:100 (n = 7). The ostriches were slaughtered for human consumption, and 80% (16 of 20) were seropositive with titers of 1:200 (n = 1), 1:400 (n = 9), and 1:800 (n = 6). Sera were tested with a modified agglutination test, and the results confirmed the distribution of the parasite in ratite species from Brazil. The data obtained in this study show that T. gondii is prevalent among ratites from Brazil, and therefore ratite meat should also be considered a potential source of human infection. This is the first report of T. gondii seroprevalence in emus.


Assuntos
Doenças das Aves/parasitologia , Paleógnatas/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/imunologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Doenças das Aves/epidemiologia , Doenças das Aves/imunologia , Brasil/epidemiologia , Dromaiidae/parasitologia , Feminino , Masculino , Carne/normas , Prevalência , Reiformes/parasitologia , Distribuição por Sexo , Struthioniformes/parasitologia
16.
PLoS Biol ; 17(10): e3000448, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31577791

RESUMO

The development of an organism involves the formation of patterns from initially homogeneous surfaces in a reproducible manner. Simulations of various theoretical models recapitulate final states of natural patterns, yet drawing testable hypotheses from those often remains difficult. Consequently, little is known about pattern-forming events. Here, we surveyed plumage patterns and their emergence in Galliformes, ratites, passerines, and penguins, together representing the three major taxa of the avian phylogeny, and built a unified model that not only reproduces final patterns but also intrinsically generates shared and varying directionality, sequence, and duration of patterning. We used in vivo and ex vivo experiments to test its parameter-based predictions. We showed that directional and sequential pattern progression depends on a species-specific prepattern: an initial break in surface symmetry launches a travelling front of sharply defined, oriented domains with self-organising capacity. This front propagates through the timely transfer of increased cell density mediated by cell proliferation, which controls overall patterning duration. These results show that universal mechanisms combining prepatterning and self-organisation govern the timely emergence of the plumage pattern in birds.


Assuntos
Galliformes/genética , Modelos Estatísticos , Paleógnatas/genética , Passeriformes/genética , Pigmentação/genética , Spheniscidae/genética , Animais , Cor , Embrião não Mamífero , Plumas/citologia , Plumas/crescimento & desenvolvimento , Plumas/metabolismo , Galliformes/anatomia & histologia , Galliformes/classificação , Galliformes/crescimento & desenvolvimento , Padrões de Herança , Morfogênese/genética , Paleógnatas/anatomia & histologia , Paleógnatas/classificação , Paleógnatas/crescimento & desenvolvimento , Passeriformes/anatomia & histologia , Passeriformes/classificação , Passeriformes/crescimento & desenvolvimento , Filogenia , Pele/citologia , Pele/crescimento & desenvolvimento , Pele/metabolismo , Spheniscidae/anatomia & histologia , Spheniscidae/classificação , Spheniscidae/crescimento & desenvolvimento
17.
J Anat ; 235(6): 1045-1056, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31432515

RESUMO

Kiwi (Aves; genus Apteryx) are famous for laying an enormous egg in comparison with their relatively small body size. Considering the peculiar gait of this flightless bird, we suspected the existence of morpho-functional trade-offs between reproduction and locomotion. To understand how structural constraints, imposed by a large egg size, might influence the terrestrial locomotion of Apteryx, we analysed the anatomy of the limb osteomuscular system in two species of kiwi (Apteryx mantelli and Apteryx owenii). We performed detailed dissections and brought to light specific anatomical features of kiwi, in comparison with other ratites and neognathous birds. Our osteological study revealed a strongly curved pelvis, a rigid tail, and enlarged ribs. Our myology study showed an unusual location of the caudofemoralis muscle origin and insertion. The insertion of the pars pelvica along the entire caudal face of the femur, contrasts with the proximal insertion usually seen in other birds. Additionally, the pars caudalis originates along the entire tail, whereas it only inserts on the uropygium in the other birds. To interpret these specificities from a functional point of view, we built three-dimensional osteomuscular models based on computed tomography scans, radiographies and our dissections. We chose three postures associated with reproductive constraints: the standing position of a gravid compared with a non-gravid bird, as well as the brooding position. The 3D model of the brooding position suggested that the enlarged ribs could support the bodyweight when leaning on the huge egg in both males and females. Moreover, we found that in gravid females, the unusual shape of the pelvis and tail allowed the huge egg to sit ventrally below the pelvis, whereas it is held closer to the rachis in other birds. The specific conformation of the limb and the insertions of the two parses of the caudofemoralis help to maintain the tail flexed, and to keep the legs adducted when carrying the egg. The caudal location of the hip and its flexed position explains the long stance phase during the strange gait of kiwi, revealing the functional trade-off between reproduction and locomotion in this emblematic New Zealand bird.


Assuntos
Fêmur/anatomia & histologia , Paleógnatas/anatomia & histologia , Pelve/anatomia & histologia , Reprodução/fisiologia , Caminhada/fisiologia , Animais , Evolução Biológica , Feminino , Músculo Esquelético/anatomia & histologia , Cauda/anatomia & histologia
18.
Syst Biol ; 68(6): 937-955, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31135914

RESUMO

Palaeognathae represent one of the two basal lineages in modern birds, and comprise the volant (flighted) tinamous and the flightless ratites. Resolving palaeognath phylogenetic relationships has historically proved difficult, and short internal branches separating major palaeognath lineages in previous molecular phylogenies suggest that extensive incomplete lineage sorting (ILS) might have accompanied a rapid ancient divergence. Here, we investigate palaeognath relationships using genome-wide data sets of three types of noncoding nuclear markers, together totaling 20,850 loci and over 41 million base pairs of aligned sequence data. We recover a fully resolved topology placing rheas as the sister to kiwi and emu + cassowary that is congruent across marker types for two species tree methods (MP-EST and ASTRAL-II). This topology is corroborated by patterns of insertions for 4274 CR1 retroelements identified from multispecies whole-genome screening, and is robustly supported by phylogenomic subsampling analyses, with MP-EST demonstrating particularly consistent performance across subsampling replicates as compared to ASTRAL. In contrast, analyses of concatenated data supermatrices recover rheas as the sister to all other nonostrich palaeognaths, an alternative that lacks retroelement support and shows inconsistent behavior under subsampling approaches. While statistically supporting the species tree topology, conflicting patterns of retroelement insertions also occur and imply high amounts of ILS across short successive internal branches, consistent with observed patterns of gene tree heterogeneity. Coalescent simulations and topology tests indicate that the majority of observed topological incongruence among gene trees is consistent with coalescent variation rather than arising from gene tree estimation error alone, and estimated branch lengths for short successive internodes in the inferred species tree fall within the theoretical range encompassing the anomaly zone. Distributions of empirical gene trees confirm that the most common gene tree topology for each marker type differs from the species tree, signifying the existence of an empirical anomaly zone in palaeognaths.


Assuntos
Genoma/genética , Paleógnatas/classificação , Paleógnatas/genética , Filogenia , Animais , Genômica
19.
Ticks Tick Borne Dis ; 10(4): 754-760, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31031164

RESUMO

Ixodes anatis is a species of endophilic (nidicolous) tick species parasitizing brown kiwi (Apteryx mantelli). Even though they are endemic to New Zealand like their host, very little is known about these ticks or their population dynamics and relationships with their hosts. We conducted a study from May 2013 to June 2014 to evaluate the effect of shelter location (one of three gullies), habitat (forest, scrub and pasture) and type (tree, soil and surface) on the abundance of the different life stages of I. anatis. In total, 12,172 ticks were collected from 63 shelters, which were sampled monthly for 11 months over the 14 month period. Un-engorged larvae predominated over other stages accounting for 87.2% of the samples collected. We found that location, habitat in which the shelters were located, and the type of shelter were significant predictors of I. anatis abundance. Tree shelters in forests had significantly higher tick abundance than those in scrub and pasture. Tree and soil shelters in general had significantly more ticks than surface shelters. Shelters located in Kauri Bush a drier site, had higher abundances than those in wetter sites. While some of these changes can be explained with the movement of the host, we believe more research needs to be done on the effect of shelters' microclimate on I. anatis' life cycle.


Assuntos
Ecossistema , Ixodes/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Paleógnatas/parasitologia , Infestações por Carrapato/veterinária , Animais , Feminino , Florestas , Ixodes/fisiologia , Larva , Masculino , Nova Zelândia/epidemiologia , Dinâmica Populacional , Infestações por Carrapato/epidemiologia , Árvores
20.
J Hum Evol ; 130: 126-140, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31010539

RESUMO

Fundamental disagreements remain regarding the relative importance of climate change and human activities as triggers for Madagascar's Holocene megafaunal extinction. We use stable isotope data from stalagmites from northwest Madagascar coupled with radiocarbon and butchery records from subfossil bones across the island to investigate relationships between megafaunal decline, climate change, and habitat modification. Archaeological and genetic evidence support human presence by 2000 years Before Common Era (BCE). Megafaunal decline was at first slow; it hastened at ∼700 Common Era (CE) and peaked between 750 and 850 CE, just before a dramatic vegetation transformation in the northwest that resulted in the replacement of C3 woodland habitat with C4 grasslands, during a period of heightened monsoonal activity. Cut and chop marks on subfossil lemur bones reveal a shift in primary hunting targets from larger, now-extinct species prior to ∼900 CE, to smaller, still-extant species afterwards. By 1050 CE, megafaunal populations had essentially collapsed. Neither the rapid megafaunal decline beginning ∼700 CE, nor the dramatic vegetation transformation in the northwest beginning ∼890 CE, was influenced by aridification. However, both roughly coincide with a major transition in human subsistence on the island from hunting/foraging to herding/farming. We offer a new hypothesis, which we call the "Subsistence Shift Hypothesis," to explain megafaunal decline and extinction in Madagascar. This hypothesis acknowledges the importance of wild-animal hunting by early hunter/foragers, but more critically highlights negative impacts of the shift from hunting/foraging to herding/farming, settlement by new immigrant groups, and the concomitant expansion of the island's human population. The interval between 700 and 900 CE, when the pace of megafaunal decline quickened and peaked, coincided with this economic transition. While early megafaunal decline through hunting may have helped to trigger the transition, there is strong evidence that the economic shift itself hastened the crash of megafaunal populations.


Assuntos
Agricultura , Extinção Biológica , Mamíferos , Paleógnatas , Animais , Arqueologia , Biodiversidade , Ecossistema , Humanos , Madagáscar
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