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1.
Nat Commun ; 11(1): 2250, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32418985

RESUMO

Explanations for the Upper Pleistocene extinction of megafauna from Sahul (Australia and New Guinea) remain unresolved. Extinction hypotheses have advanced climate or human-driven scenarios, in spite of over three quarters of Sahul lacking reliable biogeographic or chronologic data. Here we present new megafauna from north-eastern Australia that suffered extinction sometime after 40,100 (±1700) years ago. Megafauna fossils preserved alongside leaves, seeds, pollen and insects, indicate a sclerophyllous forest with heathy understorey that was home to aquatic and terrestrial carnivorous reptiles and megaherbivores, including the world's largest kangaroo. Megafauna species diversity is greater compared to southern sites of similar age, which is contrary to expectations if extinctions followed proposed migration routes for people across Sahul. Our results do not support rapid or synchronous human-mediated continental-wide extinction, or the proposed timing of peak extinction events. Instead, megafauna extinctions coincide with regionally staggered spatio-temporal deterioration in hydroclimate coupled with sustained environmental change.


Assuntos
Mudança Climática/história , Extinção Biológica , Fósseis , Animais , Austrália , Carnivoridade , Classificação , Clima , Dromaiidae , Ecossistema , Florestas , História Antiga , Humanos , Macropodidae , Marsupiais , Nova Guiné , Paleontologia , Datação Radiométrica , Répteis , Urânio
2.
Braz J Biol ; 80(1): 66-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31116295

RESUMO

Emus are large flightless birds in the ratite group and are native to Australia. Since the mid-1980s, there has been increased interest in the captive breeding of emus for the production of leather, meat and oil. The aim of this study was to identify gastrointestinal parasites in the feces of emus Dromaius novaehollandiae from a South American scientific breeding. Fecal samples collected from 13 birds were examined by direct smears, both with and without centrifugation, as well as by the fecal flotation technique using Sheather's sugar solution. Trophozoites, cysts and oocysts of protozoa and nematode eggs were morphologically and morphometrically evaluated. Molecular analysis using PCR assays with specific primers for the genera Entamoeba, Giardia and Cryptosporidium were performed. Trophozoites and cysts of Entamoeba spp. and Giardia spp., oocysts of Eimeria spp. and Isospora dromaii, as well as eggs belonging to the Ascaridida order were found in the feces. Three animals were diagnosed with Giardia spp., and three were positive for Entamoeba spp. based on PCR techniques. After analyzing the data, we concluded that emus were infected enzootically by nematode and protozoan species.


Assuntos
Criptosporidiose , Cryptosporidium , Dromaiidae , Parasitos , Animais , Brasil , Fezes
3.
Curr Biol ; 29(21): R1131-R1133, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31689398

RESUMO

The vestigial wings of emus are a striking illustration of morphological evolution. A new study points to reduced activity of an essential signaling pathway as a factor in the evolution of the emu's stunted wings.


Assuntos
Dromaiidae , Animais , Membro Anterior , Transdução de Sinais , Asas de Animais
4.
Curr Biol ; 29(21): 3681-3691.e5, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31668620

RESUMO

Powered flight was fundamental to the establishment and radiation of birds. However, flight has been lost multiple times throughout avian evolution. Convergent losses of flight within the ratites (flightless paleognaths, including the emu and ostrich) often coincide with reduced wings. Although there is a wealth of anatomical knowledge for several ratites, the genetic mechanisms causing these changes remain debated. Here, we use a multidisciplinary approach employing embryological, genetic, and genomic techniques to interrogate the mechanisms underlying forelimb heterochrony in emu embryos. We show that the initiation of limb formation, an epithelial to mesenchymal transition (EMT) in the lateral plate mesoderm (LPM) and myoblast migration into the LPM, occur at equivalent stages in the emu and chick. However, the emu forelimb fails to subsequently proliferate. The unique emu forelimb expression of Nkx2.5, previously associated with diminished wing development, initiates after this stage (concomitant with myoblast migration into the LPM) and is therefore unlikely to cause this developmental delay. In contrast, RNA sequencing of limb tissue reveals significantly lower Fgf10 expression in the emu forelimb. Artificially increasing Fgf10 expression in the emu LPM induces ectodermal Fgf8 expression and a limb bud. Analyzing open chromatin reveals differentially active regulatory elements near Fgf10 and Sall-1 in the emu wing, and the Sall-1 enhancer activity is dependent on a likely Fgf-mediated Ets transcription factor-binding site. Taken together, our results suggest that regulatory changes result in lower expression of Fgf10 and a concomitant failure to express genes required for limb proliferation in the early emu wing bud.


Assuntos
Proteínas Aviárias/genética , Dromaiidae/genética , Transição Epitelial-Mesenquimal/genética , Fator 10 de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento , Asas de Animais/embriologia , Animais , Proteínas Aviárias/metabolismo , Dromaiidae/embriologia , Fator 10 de Crescimento de Fibroblastos/metabolismo , Botões de Extremidades/embriologia , Transdução de Sinais
6.
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
7.
Rev Bras Parasitol Vet ; 28(1): 177-179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30810663

RESUMO

The study aimed to identify species of ticks present in the environment and among captive animals, in Mangaratiba, Rio de Janeiro, Brazil. Ticks were isolated from captive animals by manual examination and free-living ticks in the environment were captured using the flannel drag technique. A total of 91 ticks were obtained (51 adults, 25 nymphs and 15 larvae). The specimens were identified morphologically as Amblyomma sp., Amblyomma dubitatum, Amblyomma ovale and Amblyomma sculptum , and were distributed among five species of native mammals and an exotic bird. This study also reports the first case of infestation of the Australian emu (Dromaius novaehollandiae) by A. sculptum.


Assuntos
Dromaiidae/parasitologia , Infestações por Carrapato/veterinária , Animais , Animais Selvagens , Brasil , Dromaiidae/classificação , Infestações por Carrapato/diagnóstico , Infestações por Carrapato/parasitologia
8.
Sci Rep ; 9(1): 1966, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30760849

RESUMO

Many ideas have been put forward for the adaptive value of the cassowary casque; and yet, its purpose remains speculative. Homeothermic animals elevate body temperature through metabolic heat production. Heat gain must be offset by heat loss to maintain internal temperatures within a range for optimal performance. Living in a tropical climate, cassowaries, being large bodied, dark feathered birds, are under thermal pressure to offload heat. We tested the original hypothesis that the casque acts as a thermal window. With infrared thermographic analyses of living cassowaries over an expansive range of ambient temperatures, we provide evidence that the casque acts as a thermal radiator, offloading heat at high temperatures and restricting heat loss at low temperatures. Interestingly, at intermediate temperatures, the casque appears thermally heterogeneous, with the posterior of the casque heating up before the front half. These findings might have implications for the function of similar structures in avian and non-avian dinosaurs.


Assuntos
Temperatura Corporal/fisiologia , Dromaiidae/fisiologia , Termogênese/fisiologia , Termografia/veterinária , Animais , Aves , Tempo (Meteorologia)
9.
J Zoo Wildl Med ; 49(4): 967-976, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30592921

RESUMO

The husbandry and medical records, and necropsy reports, of 1,002 captive Struthioniformes that died at the Réserve Africaine de Sigean (France) from 1974 to 2015 were examined. The goal of this study was to determine the most common causes of mortality in ostriches ( Struthio camelus), emus ( Dromaius novaehollandiae), and American rheas ( Rhea americana), in order to highlight common causes of mortality, as well as the influence of age, gender, and rearing methods on mortality. The most prevalent cause of mortality was pathology of digestive origin in the neonates of all three species, especially yolk-sac infections, which accounted for 41% of all deaths in this captive neonate population and was especially prevalent in hand-reared neonates. Other causes included musculoskeletal disorders in emus (particularly hand-reared) and rheas; trauma in neonate ostriches, mainly due to crushing by parents; leg deformities in emu chicks and juveniles; general sepsis in hand-reared ratite chicks due to a chlamydiosis outbreaks (1989-1990); trauma by conspecifics in subadult ostriches and emus; stress myopathy in subadult rheas, particularly after introduction to a new enclosure; evisceration inflicted by herbivorous enclosure mates on adult male ostriches; fatal peritonitis following salpingitis in adult female ostriches; and death associated with ocular disorder in adult male emus. Although this study was conducted at one institution, and its results reflect this zoo's management and zootechnical practices, its findings could well have implications for management practices involving other captive Struthioniforme populations.


Assuntos
Doenças das Aves/mortalidade , Dromaiidae , Reiformes , Struthioniformes , Animais , Animais de Zoológico , Doenças das Aves/etiologia , França , Estudos Retrospectivos
10.
PLoS One ; 13(6): e0198956, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29949597

RESUMO

Allogeneic lung transplant is limited both by the shortage of available donor lungs and by the lack of suitable long-term lung assist devices to bridge patients to lung transplantation. Avian lungs have different structure and mechanics resulting in more efficient gas exchange than mammalian lungs. Decellularized avian lungs, recellularized with human lung cells, could therefore provide a powerful novel gas exchange unit for potential use in pulmonary therapeutics. To initially assess this in both small and large avian lung models, chicken (Gallus gallus domesticus) and emu (Dromaius novaehollandiae) lungs were decellularized using modifications of a detergent-based protocol, previously utilized with mammalian lungs. Light and electron microscopy, vascular and airway resistance, quantitation and gel analyses of residual DNA, and immunohistochemical and mass spectrometric analyses of remaining extracellular matrix (ECM) proteins demonstrated maintenance of lung structure, minimal residual DNA, and retention of major ECM proteins in the decellularized scaffolds. Seeding with human bronchial epithelial cells, human pulmonary vascular endothelial cells, human mesenchymal stromal cells, and human lung fibroblasts demonstrated initial cell attachment on decellularized avian lungs and growth over a 7-day period. These initial studies demonstrate that decellularized avian lungs may be a feasible approach for generating functional lung tissue for clinical therapeutics.


Assuntos
Bioengenharia/métodos , Galinhas , Dromaiidae , Pulmão/citologia , Tecidos Suporte , Animais , Apoptose , Proliferação de Células , Matriz Extracelular/metabolismo , Humanos
11.
Biol Lett ; 14(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618519

RESUMO

Australia's iconic emu (Dromaius novaehollandiae novaehollandiae) is the only living representative of its genus, but fossil evidence and reports from early European explorers suggest that three island forms (at least two of which were dwarfs) became extinct during the nineteenth century. While one of these-the King Island emu-has been found to be conspecific with Australian mainland emus, little is known about how the other two forms-Kangaroo Island and Tasmanian emus-relate to the others, or even the size of Tasmanian emus. We present a comprehensive genetic and morphological analysis of Dromaius diversity, including data from one of the few definitively genuine Tasmanian emu specimens known. Our genetic analyses suggest that all the island populations represent sub-populations of mainland Dnovaehollandiae Further, the size of island emus and those on the mainland appears to scale linearly with island size but not time since isolation, suggesting that island size-and presumably concomitant limitations on resource availability-may be a more important driver of dwarfism in island emus, though its precise contribution to emu dwarfism remains to be confirmed.


Assuntos
Dromaiidae/anatomia & histologia , Dromaiidae/genética , Nanismo/genética , Fósseis , Variação Genética , Animais , Austrália , Ilhas
12.
J Oleo Sci ; 67(4): 471-477, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29526880

RESUMO

Emu is the second-largest extant bird native to Australia. Emu oil, obtained from the emu's fat deposits, is used as an ingredient in cosmetic skincare products. Emu oil has been reported to improve several inflammatory symptoms; however, the mechanisms of these anti-inflammatory effects are largely unknown. This study investigated the effects of emu oil on the inflammatory macrophage response in vitro. A murine macrophage cell line, RAW 264, was incubated in culture media supplemented with or without emu oil and stimulated with lipopolysaccharide (LPS). We determined phagocytic activity by measuring the number of fluorescent microspheres taken up by the cells. The phagocytic activity of RAW 264 cells in the presence of LPS was unaffected by emu oil. We also determined production of nitric oxide (NO) and tumor necrosis factor (TNF)-α in the culture medium using the Griess reaction and an enzyme-linked immunosorbent assay, respectively, and the protein expression of inducible NO synthase (iNOS) using western blotting. The results indicated that emu oil reduced the LPS-induced production of NO, TNF-α, and iNOS expression in a dose-dependent manner. The results suggested that emu oil does not reduce the phagocytic clearance rate of inflammatory matter; however, it does reduce the production of NO and TNF-α in macrophages. These latter products enhance the inflammatory response and emu oil thereby demonstrated anti-inflammatory properties.


Assuntos
Anti-Inflamatórios , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óleos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Relação Dose-Resposta a Droga , Dromaiidae , Ensaio de Imunoadsorção Enzimática/métodos , Camundongos , Fagocitose/efeitos dos fármacos , Células RAW 264.7
13.
J Comp Pathol ; 159: 31-35, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29599003

RESUMO

A 17-year-old female emu (Dromaius novaehollandiae) was presented for clinical evaluation due to a 3-week history of anorexia and progressive weight loss. The emu died after sedation. At necropsy examination, the ovary and the majority of the oviduct were effaced by a multinodular cystic mass and accompanied by 6 l of coelomic effusion. Histopathology revealed a neoplasm composed of well-differentiated, poorly organized tissues derived from ectoderm, mesoderm and endoderm. Tissues within the neoplasm expressed glial fibrillary acidic protein, desmin and cytokeratins AE1/AE3, respectively, confirming the diagnosis of teratocarcinoma.


Assuntos
Dromaiidae , Neoplasias Ovarianas/veterinária , Teratocarcinoma/veterinária , Animais , Feminino
14.
Poult Sci ; 97(4): 1117-1119, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29300990

RESUMO

Male and female emus are nearly identical both as chicks and as adults. Although morphological differences of the internal genital tract can be used to distinguish the sexes, a high degree of diagnostic skill is required for accurate sexing. DNA-based sexing methods are highly accurate and can be used to diagnose sex without requiring a high degree of technical skill. However, conventional PCR-RFLP is time consuming and costly, requiring the digestion of PCR products. In this study, we simplified the protocol for sexing the emu by using multiplex PCR without restriction enzyme treatment. Multiplex PCR based on a W-specific primer, with the commonly designed primer set on both Z and W chromosomes, amplified both 197-bp and 272-bp bands in the female, and only the 272-bp band in the male. Sexing results obtained in this way were completely concordant with results obtained using the conventional PCR-RFLP method. Thus, we succeeded in simplifying the protocol for sexing the emu, and suggest that our protocol improves production efficiency by facilitating rapid pairing and selection of individuals to establish high-quality pedigrees.


Assuntos
Dromaiidae , Reação em Cadeia da Polimerase Multiplex/veterinária , Análise para Determinação do Sexo/veterinária , Animais , Primers do DNA/análise , Dromaiidae/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Análise para Determinação do Sexo/métodos
15.
Avian Pathol ; 47(1): 100-107, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28911234

RESUMO

Clinicopathological diagnosis of mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome B), an inherited autosomal recessive lysosomal storage disease, as a cause of losses in a commercial emu flock and screening breeders using a mutation-specific DNA test are described. Between 2012 and 2015, ∼5-10 juvenile emus from a few weeks to several months of age developed progressive neurological signs and died while others in the flock remained healthy. Necropsy of two affected siblings revealed multiple sites of haemorrhage, cytoplasmic periodic acid-Schiff and Luxol fast blue-positive inclusions in neurons, and aggregates of foamy macrophages in visceral organs. Affected emus were homozygous for the two-base deletion in the α-N-acetylglucosaminidase gene that causes MPS IIIB in emus. Mutation-specific DNA tests for MPS IIIB in emus were developed. Screening blood samples from 78 breeding emus revealed 14 (18%; 9 males, 4 females, and 1 unknown gender) carriers; an overall 0.09 mutant α-N-acetylglucosaminidase allele frequency. A "test and cull male carriers" programme, in which carrier males are culled but carrier females are retained, was proposed to avoid breeding affected emus together, ultimately eliminating the disease from future broods, and preserving the gene pool with as much breeding stock as possible. Molecular genetic diagnostic tests are simple, precise, and permit screening of all breeders for the mutant allele in any flock and can be used to eliminate MPS IIIB-related emu losses through informed breeding.


Assuntos
Doenças das Aves/genética , Dromaiidae , Mucopolissacaridose III/veterinária , Acetilglucosaminidase/genética , Acetilglucosaminidase/metabolismo , Animais , Doenças das Aves/patologia , Feminino , Deleção de Genes , Regulação Enzimológica da Expressão Gênica , Predisposição Genética para Doença , Genótipo , Masculino , Mucopolissacaridose III/genética , Mucopolissacaridose III/patologia
16.
Avian Pathol ; 47(1): 58-62, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28862888

RESUMO

An adult female emu (Dromaius novaehollandiae) presented with anorexia, maldigestion, weight loss, and various subtle nervous deficits. After four months of unrewarding diagnostics, treatments, and supportive care, the emu was euthanized due to lack of clinical improvement and progressive weight loss. Gross pathology revealed a very narrow pylorus and multiple flaccid diverticula of the small intestines. Histopathological findings included severe lymphoplasmacytic encephalomyelitis and multifocal lymphocytic neuritis associated with the gastrointestinal tract. Immunohistochemistry and polymerase chain reaction on the brain were positive for an avian bornavirus (ABV), and partial sequencing of the matrix gene identified aquatic bird bornavirus-1 (ABBV-1), 100% identical to viruses circulating in wild Canada geese (Branta canadensis). As wild geese frequently grazed and defaecated in the emu's outdoor exhibit, natural transmission of ABBV-1 from free-ranging waterfowl to the emu was presumed to have occurred.


Assuntos
Doenças das Aves/virologia , Bornaviridae/genética , Dromaiidae , Infecções por Mononegavirales/veterinária , Animais , Animais de Zoológico , Anseriformes/virologia , Feminino , Infecções por Mononegavirales/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
17.
Poult Sci ; 97(3): 1032-1040, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253213

RESUMO

In this study, we analyzed selected morphological traits of eggs, as well as structure, strength, and protein composition of the vitelline membrane (VM) of ostrich, emu, and greater rhea eggs. Ninety eggs (30 for species) were analyzed for the following parameters: egg weight, yolk weight, yolk ratio, and yolk index. In addition, pH value, water activity, consistency index, and flow behavior index were determined. The strength of VM was measured using the TA.HDPlus Texture Analyzer. Micrograph images were taken via a scanning electron microscope. Polyacrylamide gel electrophoresis was conducted under denaturing conditions. Ostrich eggs were characterized by the highest egg and yolk weight compared with those of emu and greater rhea eggs, whereas emu eggs had the highest yolk ratio compared with those of ostrich and greater rhea eggs (P > 0.05). Yolk content differed among the species in terms of water activity; it was found to be higher in emu eggs than in ostrich and greater rhea eggs (P > 0.05). Based on flow curves, yolks of the ratites were classified as pseudoplastic non-Newtonian fluids. The consistency index was significantly higher in yolks of ostrich and emu than that of greater rhea eggs, whereas the VM of yolks of greater rhea eggs was the most resistant (had the highest breaking force = 26.4 g). All species differed significantly regarding the structure of VM, the outer layer (OL) in particular, which was found to constitute fibers of various thicknesses that were differently arranged. Fibers of the OL of the VM of emu, whose fibers were the least differentiated but formed the most compact network, were the most diverse in characterization. An electropherogram of the VM of ostrich revealed 11 primary protein bands: 6 for the OL and 5 for the inner layer (IL), that of emu revealed 9 bands: 5 for the OL and 4 for the IL, and that of greater rhea revealed 10 bands: 6 for the OL and 4 for the IL.


Assuntos
Dromaiidae/fisiologia , Óvulo/fisiologia , Reiformes/fisiologia , Struthioniformes/fisiologia , Membrana Vitelina/fisiologia , Animais , Gema de Ovo/química , Gema de Ovo/fisiologia
18.
Exp Appl Acarol ; 73(1): 103-107, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28849543

RESUMO

For the first time, infestation of the Australian emu by a native tick is recorded based on an engorged adult female specimen of the southern paralysis tick (Ixodes cornuatus) taken from a captive emu at Healesville sanctuary, Victoria, Australia. Tick paralysis in Australian birds is discussed.


Assuntos
Doenças das Aves/parasitologia , Dromaiidae , Ixodidae/fisiologia , Infestações por Carrapato/veterinária , Paralisia por Carrapato/veterinária , Animais , Austrália , Infestações por Carrapato/parasitologia , Paralisia por Carrapato/parasitologia , Vitória
19.
Nat Commun ; 8(1): 132, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743862

RESUMO

The ratites are a distinctive clade of flightless birds, typified by the emu and ostrich that have acquired a range of unique anatomical characteristics since diverging from basal Aves at least 100 million years ago. The emu possesses a vestigial wing with a single digit and greatly reduced forelimb musculature. However, the embryological basis of wing reduction and other anatomical changes associated with loss of flight are unclear. Here we report a previously unknown co-option of the cardiac transcription factor Nkx2.5 to the forelimb in the emu embryo, but not in ostrich, or chicken and zebra finch, which have fully developed wings. Nkx2.5 is expressed in emu limb bud mesenchyme and maturing wing muscle, and mis-expression of Nkx2.5 throughout the limb bud in chick results in wing reductions. We propose that Nkx2.5 functions to inhibit early limb bud expansion and later muscle growth during development of the vestigial emu wing.The transcription factor Nkx2.5 is essential for heart development. Here, the authors identify a previously unknown expression domain for Nkx2.5 in the emu wing and explore its role in diminished wing bud development in the flightless emu, compared with three other birds that have functional wings.


Assuntos
Proteínas Aviárias/genética , Proteína Homeobox Nkx-2.5/genética , Fatores de Transcrição/genética , Asas de Animais/metabolismo , Animais , Proteínas Aviárias/metabolismo , Dromaiidae , Membro Anterior/embriologia , Membro Anterior/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ , Botões de Extremidades/embriologia , Botões de Extremidades/metabolismo , Mesoderma/embriologia , Mesoderma/metabolismo , Músculo Esquelético/embriologia , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Asas de Animais/embriologia
20.
Br Poult Sci ; 58(5): 471-479, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28604099

RESUMO

1. The aim of this study was to present selected elements of emu behaviour in three different seasons (the non-breeding season, the pre-breeding season and the breeding season) and in the morning and afternoon. The study focused on feed, water and sand intake; plumage care; resting; agonistic behaviour and other activities, mostly standing still, aimless walking or observing the surroundings. 2. The troop consisted of 11 emus (5 females and 6 males) aged 12 years, kept in a free-range system. Observations were carried out during a period of 3 weeks in each season, during which 60-min observation sessions took place on 3 randomly chosen days. 3. A significant effect was found of each season on the behaviour patterns related to feeding, sand intake, plumage care, resting and agonistic behaviour. 4. Time of day affected the behaviour associated with the collection of food and water, foraging, pecking and ingesting sand and plumage preening. 5. Most of the time, regardless of season and time of day, the emus were standing still, walking aimlessly or observing the surrounding area.


Assuntos
Criação de Animais Domésticos , Comportamento de Ingestão de Líquido , Dromaiidae/fisiologia , Comportamento Alimentar , Atividade Motora , Comportamento Agonístico , Animais , Feminino , Asseio Animal , Masculino , Estações do Ano
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