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1.
Sheng Li Xue Bao ; 73(3): 518-526, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34230953

RESUMO

Cyclic adenosine monophosphate (cAMP) is one of the significant and conserved second messengers in mammals, and it participates in regulating the developmental and physiological functions of various organs and tissues through transducting extracellular signals. Studies have shown that the process of meiosis in female mammalian oocytes is closely related to the level of cAMP and strictly regulated. In oocytes, cAMP is mainly synthesized by adenylate cyclase 3 (AC3) and degraded by phosphodiesterase 3A (PDE3A), both of which jointly regulate the level of cAMP in oocytes and play important roles in the follicular development and oogenesis of female ovaries. It has been well illuminated that high level of cAMP in the cytoplasm of oocytes in growing follicles could maintain the arrest of the first meiotic of oocytes for a long time. The oocytes will resume meiosis and mature either when the synthesis of cAMP is down-regulated, or when cAMP is degraded by PDE3A. In recent years, the novo physiological functions of cAMP in oogenesis have been reported. To better understand the regulatory role and mechanism of cAMP in mammalian gametogenesis, this paper reviews the relevant research regarding the relationship between cAMP and germ cell development.


Assuntos
AMP Cíclico , Meiose , Monofosfato de Adenosina , Animais , Feminino , Mamíferos , Oócitos , Oogênese
2.
Emerg Infect Dis ; 27(8): 2073-2080, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34286685

RESUMO

Wild animals have been implicated as the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but it is largely unknown how the virus affects most wildlife species and if wildlife could ultimately serve as a reservoir for maintaining the virus outside the human population. We show that several common peridomestic species, including deer mice, bushy-tailed woodrats, and striped skunks, are susceptible to infection and can shed the virus in respiratory secretions. In contrast, we demonstrate that cottontail rabbits, fox squirrels, Wyoming ground squirrels, black-tailed prairie dogs, house mice, and racoons are not susceptible to SARS-CoV-2 infection. Our results expand the knowledge base of susceptible species and provide evidence that human-wildlife interactions could result in continued transmission of SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Animais Selvagens , Suscetibilidade a Doenças , Humanos , Mamíferos , Camundongos
3.
Adv Exp Med Biol ; 1208: 99-114, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260024

RESUMO

Autophagy, a highly conserved metabolic process in eukaryotes, is a widespread degradation/recycling system. However, there are significant differences (as well as similarities) between autophagy in animals, plants, and microorganisms such as yeast. While the overall process of autophagy is similar between different organisms, the molecular mechanisms and the pathways regulating autophagy are different, which is manifested in the diversity and specificity of the genes involved. In general, the autophagy system is much more complicated in mammals than in yeast. In addition, there are some differences in the types of autophagy present in animals, plants, and microorganisms. For example, there is a unique type of selective autophagy called the cytoplasm-to-vacuole targeting (Cvt) pathway in yeast, and a special kind of autophagy, chloroplast autophagy, exists in plants. In conclusion, although autophagy is highly conserved in eukaryotes, there are still many differences between autophagy of animals, plants, and microorganisms.


Assuntos
Autofagia , Vacúolos , Animais , Citoplasma , Mamíferos/genética , Saccharomyces cerevisiae
4.
Adv Exp Med Biol ; 1208: 175-190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260027

RESUMO

Macroautophagy (referred to as autophagy hereafter) is a highly conserved catabolic process in eukaryotic cells. Autophagy is essential for cellular homeostasis through elimination and recycling of large cytoplasmic components, such as abnormal protein aggregates and damaged organelles, via lysosomal degradation. Since being originally identified by genetic screening in yeast, autophagy-related (ATG) genes have played a central role in autophagy research in different organisms, including plants, worms, flies, and mammals. Mouse models for monitoring autophagic activity or clarifying its biological functions have also been established. These mice are powerful tools to investigate roles of autophagy in vivo. Owing to the rapid technological advances in molecular biology, it is ever more efficient and simpler to manipulate autophagy-associated genes. Herein, we will introduce some commonly used approaches of gene silencing in mammalian cells, including CRIPSR/Cas9-mediated gene knockout and siRNA- and shRNA-mediated gene knockdown. We also summarized the common mouse models used for assessing autophagy. We hope to bring the researchers some useful information as they study autophagy.


Assuntos
Autofagia , Lisossomos , Animais , Autofagia/genética , Mamíferos , Camundongos , Proteínas , Saccharomyces cerevisiae
5.
Mem Inst Oswaldo Cruz ; 116: e200427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259735

RESUMO

BACKGROUND: Trypanosomatids are widespread and cause diseases - such as trypanosomiasis, sleeping sickness, Chagas disease, and cutaneous and visceral leishmaniasis - in animals and humans. These diseases occur in both rural and urban regions due to unplanned growth and deforestation. Thus, wild and synanthropic reservoir hosts living in residential areas are risk factors. OBJECTIVE: We aimed to evaluate the diversity of small mammals (rodents and marsupials), and the occurrence of trypanosomatids, especially Leishmania, in the rural settlement of Presidente Figueiredo, Amazonas. METHODS: Animals were collected using Sherman, Tomahawk, and Pitfall traps along 16 trails in four landscapes: continuous forest, forest with planting, planting, and peridomiciliar. Leishmania sp. was detected in liver samples by polymerase chain reaction targeting kDNA. FINDINGS: Diversity was higher in forests with planting and lower around residences. In total, 135 mammals (81 rodents and 54 marsupials covering 14 genera) were captured. Rodents presented infection rates (IR) of 74% and marsupials of 48%. Rodents in domicile landscapes presented a higher IR (92.9%), while marsupials showed a higher IR in forests (53.3%). MAIN CONCLUSIONS: The results suggest high prevalence of trypanosomatids across 12 mammalian genera possibly involved as reservoir hosts in the enzootic transmission of leishmaniasis in the Amazon's rural, peridomiciliar landscape.


Assuntos
Leishmania , Marsupiais , Animais , Brasil/epidemiologia , Leishmania/genética , Mamíferos , Roedores
6.
Adv Exp Med Biol ; 1332: 85-105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34251640

RESUMO

Arginine is a key amino acid in pregnant females as it is the precursor for nitric oxide (NO) via nitric oxide synthase and for polyamines (putrescine, spermidine, and spermine) by either arginase II and ornithine decarboxylase to putrescine or via arginine decarboxylase to agmatine and agmatine to putrescine via agmatinase. Polyamines are critical for placental growth and vascularization. Polyamines stabilize DNA and mRNA for gene transcription and mRNA translation, stimulate proliferation of trophectoderm, and formation of multinucleated trophectoderm cells that give rise to giant cells in the placentae of species such as mice. Polyamines activate MTOR cell signaling to stimulate protein synthesis and they are important for motility through modification of beta-catenin phosphorylation, integrin signaling via focal adhesion kinases, cytoskeletal organization, and invasiveness or superficial implantation of blastocysts. Physiological levels of arginine, agmatine, and polyamines are critical to the secretion of interferon tau for pregnancy recognition in ruminants. Arginine, polyamines, and agmatine are very abundant in fetal fluids, fetal blood, and tissues of the conceptus during gestation. The polyamines are thus available to influence a multitude of events including activation of development of blastocysts, implantation, placentation, fetal growth, and development required for the successful establishment and maintenance of pregnancy in mammals.


Assuntos
Agmatina , Poliaminas , Animais , Arginina , Feminino , Mamíferos , Camundongos , Placenta , Gravidez
7.
Zootaxa ; 4975(2): 201252, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34186567

RESUMO

Type material of 12 mammal taxa originally proposed as species or subspecies are housed in the former Macleay Museum (now Macleay Collections, Chau Chak Wing Museum), University of Sydney and consist of seven holotypes and 12 syntypes. These were published from 1875 to 1887, five by N.N. Miklouho-Maclay and seven by E.P. Ramsay, of which six are currently considered valid taxa. Six type specimens are identified in the Collection for the first time. This includes rediscovery of the holotype skull of the New Guinean forest wallaby Dorcopsis chalmersii Miklouho-Maclay not reported since its description in 1884, a likely syntype of the bandicoot Perameles macroura torosa Ramsay, and three additional syntypes of the flying fox Pteropus (Epomops?) epularius Ramsay. The holotype of the dasyurid Antechinus (Podabrus) froggatti Ramsay, housed at the Australian Museum since before 1959, is also discussed. Limited specimen data currently prevents validation of an additional six specimens identified here as suspected syntypes of four further names: the macropodoids Halmaturus mastersii Krefft, Halmaturus crassipes Ramsay and Hypsiprymnodon moschatus Ramsay, and the bandicoot Perameles moresbyensis Ramsay. Individual accounts are given for a total of 21 proposed names. Type material of four of these remain unlocated in world collections and it is not known if they were ever in the Macleay Collections: the bandicoot Brachymelis garagassi Miklouho-Maclay, 1884; the wallaby Macropus tibol Miklouho-Maclay, 1885; the cuscus Cuscus chrysorrhous var. goldiei Ramsay and the giant rat Hapalotis papuanus Ramsay. The nomenclatural status of the possum Phalangista pinnata Ramsay, 1877, a possible nomen nudum, is also discussed. No nomenclatural actions are taken in this paper.


Assuntos
Mamíferos/classificação , Animais , Austrália , Museus
8.
Zootaxa ; 4979(1): 7094, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34187013

RESUMO

Zootaxa came as a new and innovative publication medium for taxonomy, amidst a scenario of devaluation of this important biological science. After 20 years, it has ascertained itself as one of the main journals in animal taxonomy. However, the contribution of the journal to the taxonomy of Mammalia (mammals), one of the most studied groups of animals with a long-standing, dedicated spectrum of specialized journals (mammalogy), could have been expected as minor. All the current and former editors of the Mammalia section of Zootaxa analyzed the relative contribution of the journal to the description of new species of mammals since 2001. We also analyzed the contribution of Zootaxa by taxon, geographic origin of taxa, and geographic origin of first authors. The taxonomic methodology of authors in species description is described as well as the temporal trends in publications and publication subjects. We highlight the editors' picks and eventually, the challenges for the future. We found that Zootaxa has had a significant contribution to mammalogy, being the second journal (the first being Journal of Mammalogy) in terms of number of new species described (76; 10.6% of the new mammalian species described between 2001 and 2020). The majority of the new species were described following an integrative taxonomic approach with at least two sources of data (86%). The analysis of published taxa, their geographic origin, and the country of origin of first authors shows a wide coverage and exhaustive representation, except for the species from the Nearctic. We conclude that Zootaxa has likely responded to a repressed demand for an additional taxonomic journal in mammalogy, with as possible appeals the absence of publication fees and an established publication speed. With 246 articles published in the past 20 years, the Mammalia section of Zootaxa embraces a large spectrum of systematic subjects going beyond alpha taxonomy. The challenges for the future are to encourage publications of authors from the African continent, still poorly represented, and from the palaeontology community, as the journal has been open to palaeontology since its early days.


Assuntos
Mamíferos/classificação , Animais , Publicações Periódicas como Assunto
9.
Nat Commun ; 12(1): 3694, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140481

RESUMO

Various prioritisation strategies have been developed to cope with accelerating biodiversity loss and limited conservation resources. These strategies could become more engaging for decision-makers if they reflected the positive effects conservation can have on future projected biodiversity, by targeting net positive outcomes in future projected biodiversity, rather than reflecting the negative consequences of further biodiversity losses only. Hoping to inform the post-2020 biodiversity framework, we here apply this approach of targeting net positive outcomes in future projected biodiversity to phylogenetic diversity (PD) to re-identify species and areas of interest for conserving global mammalian PD. We identify priority species/areas as those whose protection would maximise gains in future projected PD. We also identify loss-significant species/areas as those whose/where extinction(s) would maximise losses in future projected PD. We show that our priority species/areas differ from loss-significant species/areas. While our priority species are mostly similar to those identified by the EDGE of Existence Programme, our priority areas generally differ from previously-identified ones for global mammal conservation. We further highlight that these newly-identified species/areas of interest currently lack protection and offer some guidance for their future management.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecologia/métodos , Espécies em Perigo de Extinção , África Austral , Animais , Ásia Central , Ásia Sudeste , Evolução Biológica , Espécies em Perigo de Extinção/estatística & dados numéricos , Extinção Biológica , Madagáscar , Mamíferos , Filogenia
10.
Environ Pollut ; 284: 117452, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077898

RESUMO

Pharmaceuticals are considered emerging contaminants in terms of impacts on wildlife. One chemical group of concern is euthanasia agents used in veterinary medicine. Here we present data on the occurrence of barbiturate intoxication using samples collected from 2004 to 2020 of suspected wildlife and domestic animal poisoning cases in Spain (n = 3210). Barbiturate intoxication was seen in 3.4% (45/1334) of the total number of confirmed intoxicated animals. Barbiturates were detected in 0.2% (1/448) of baits containing detectable poisons. The most frequently detected barbiturate was pentobarbital (42/45, 93.3%), but we also detected phenobarbital, barbital, and thiopental (2.2% prevalence for each). Avian scavengers were most frequently affected by barbiturate intoxication (n = 36), especially Eurasian griffon vultures (Gyps fulvus) (n = 28). Median pentobarbital concentrations detected in intoxicated griffon vultures was 27.3 mg kg-1 in gastric content and 38.1 mg kg-1 in liver, which highlights the acute effect of the chemical soon after ingestion. At least two large intoxication events affecting griffon vultures were related to the consumption of carcasses from euthanized livestock. We also found phenobarbital in a prepared bait linked to the intoxication of one Eurasian buzzard (Buteo buteo). This study highlights the need for stronger regulation of barbiturates to avoid secondary intoxications due to improper disposal of euthanized livestock.


Assuntos
Falconiformes , Animais , Barbitúricos , Incidência , Mamíferos , Espanha/epidemiologia
11.
FASEB J ; 35(7): e21732, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34143450

RESUMO

Acid ceramidase (murine gene code: Asah1) (50 kDa) belongs to N-terminal nucleophile hydrolase family. This enzyme is located in the lysosome, which mediates conversion of ceramide (CER) into sphingosine and free fatty acids at acidic pH. CER plays an important role in intracellular sphingolipid metabolism and its increase causes inflammation. The mammalian target of rapamycin complex 1 (mTORC1) signaling on late endosomes (LEs)/lysosomes may control cargo selection, membrane biogenesis, and exosome secretion, which may be fine controlled by lysosomal sphingolipids such as CER. This lysosomal-CER-mTOR signaling may be a crucial molecular mechanism responsible for development of arterial medial calcification (AMC). Torin-1 (5 mg/kg/day), an mTOR inhibitor, significantly decreased aortic medial calcification accompanied with decreased expression of osteogenic markers like osteopontin (OSP) and runt-related transcription factor 2 (RUNX2) and upregulation of smooth muscle 22α (SM22-α) in mice receiving high dose of Vitamin D (500 000 IU/kg/day). Asah1fl/fl /SMCre mice had markedly increased co-localization of mTORC1 with lysosome-associated membrane protein-1 (Lamp-1) (lysosome marker) and decreased co-localization of vacuolar protein sorting-associated protein 16 (VPS16) (a multivesicular bodies [MVBs] marker) with Lamp-1, suggesting mTOR activation caused reduced MVBs interaction with lysosomes. Torin-1 significantly reduced the co-localization of mTOR vs Lamp-1, increased lysosome-MVB interaction which was associated with reduced accumulation of CD63 and annexin 2 (exosome markers) in the coronary arterial wall of mice. Using coronary artery smooth muscle cells (CASMCs), Pi -stimulation significantly increased p-mTOR expression in Asah1fl/fl /SMCre CASMCs as compared to WT/WT cells associated with increased calcium deposition and mineralization. Torin-1 blocked Pi -induced calcium deposition and mineralization. siRNA mTOR and Torin-1 significantly reduce co-localization of mTORC1 with Lamp-1, increased VPS16 vs Lamp-1 co-localization in Pi -stimulated CASMCs, associated with decreased exosome release. Functionally, Torin-1 significantly reduces arterial stiffening as shown by restoration from increased pulse wave velocity and decreased elastin breaks. These results suggest that lysosomal CER-mTOR signaling may play a critical role for the control of lysosome-MVB interaction, exosome secretion and arterial stiffening during AMC.


Assuntos
Ceramidase Ácida/metabolismo , Exossomos/metabolismo , Mamíferos/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteogênese/fisiologia , Sirolimo/metabolismo , Animais , Aorta/metabolismo , Cálcio/metabolismo , Ceramidas/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Vasos Coronários/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Corpos Multivesiculares/metabolismo , Análise de Onda de Pulso/métodos , Transdução de Sinais/fisiologia , Esfingolipídeos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Calcificação Vascular/metabolismo
12.
Nat Commun ; 12(1): 3954, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172731

RESUMO

Our knowledge of viral host ranges remains limited. Completing this picture by identifying unknown hosts of known viruses is an important research aim that can help identify and mitigate zoonotic and animal-disease risks, such as spill-over from animal reservoirs into human populations. To address this knowledge-gap we apply a divide-and-conquer approach which separates viral, mammalian and network features into three unique perspectives, each predicting associations independently to enhance predictive power. Our approach predicts over 20,000 unknown associations between known viruses and susceptible mammalian species, suggesting that current knowledge underestimates the number of associations in wild and semi-domesticated mammals by a factor of 4.3, and the average potential mammalian host-range of viruses by a factor of 3.2. In particular, our results highlight a significant knowledge gap in the wild reservoirs of important zoonotic and domesticated mammals' viruses: specifically, lyssaviruses, bornaviruses and rotaviruses.


Assuntos
Aprendizado de Máquina , Mamíferos/virologia , Fenômenos Fisiológicos Virais , Animais , Reservatórios de Doenças/virologia , Especificidade de Hospedeiro , Humanos , Mamíferos/classificação , Mamíferos/fisiologia , Reprodutibilidade dos Testes , Viroses/transmissão , Viroses/virologia , Vírus/classificação , Zoonoses/transmissão , Zoonoses/virologia
13.
Nat Commun ; 12(1): 3616, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127663

RESUMO

Protein dynamics are often invoked in explanations of enzyme catalysis, but their design has proven elusive. Here we track the role of dynamics in evolution, starting from the evolvable and thermostable ancestral protein AncHLD-RLuc which catalyses both dehalogenase and luciferase reactions. Insertion-deletion (InDel) backbone mutagenesis of AncHLD-RLuc challenged the scaffold dynamics. Screening for both activities reveals InDel mutations localized in three distinct regions that lead to altered protein dynamics (based on crystallographic B-factors, hydrogen exchange, and molecular dynamics simulations). An anisotropic network model highlights the importance of the conformational flexibility of a loop-helix fragment of Renilla luciferases for ligand binding. Transplantation of this dynamic fragment leads to lower product inhibition and highly stable glow-type bioluminescence. The success of our approach suggests that a strategy comprising (i) constructing a stable and evolvable template, (ii) mapping functional regions by backbone mutagenesis, and (iii) transplantation of dynamic features, can lead to functionally innovative proteins.


Assuntos
Luciferases/química , Luciferases/genética , Luciferases/metabolismo , Simulação de Dinâmica Molecular , Engenharia de Proteínas , Animais , Sítios de Ligação , Catálise , Estabilidade Enzimática , Cinética , Luciferases de Renilla/química , Luciferases de Renilla/genética , Luciferases de Renilla/metabolismo , Mamíferos , Camundongos , Mutagênese , Mutação , Células NIH 3T3 , Conformação Proteica , Temperatura
14.
Nat Commun ; 12(1): 3808, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155206

RESUMO

Reproductive success depends on efficient sperm movement driven by axonemal dynein-mediated microtubule sliding. Models predict sliding at the base of the tail - the centriole - but such sliding has never been observed. Centrioles are ancient organelles with a conserved architecture; their rigidity is thought to restrict microtubule sliding. Here, we show that, in mammalian sperm, the atypical distal centriole (DC) and its surrounding atypical pericentriolar matrix form a dynamic basal complex (DBC) that facilitates a cascade of internal sliding deformations, coupling tail beating with asymmetric head kinking. During asymmetric tail beating, the DC's right side and its surroundings slide ~300 nm rostrally relative to the left side. The deformation throughout the DBC is transmitted to the head-tail junction; thus, the head tilts to the left, generating a kinking motion. These findings suggest that the DBC evolved as a dynamic linker coupling sperm head and tail into a single self-coordinated system.


Assuntos
Motilidade Espermática/fisiologia , Animais , Centríolos/fisiologia , Centríolos/ultraestrutura , Humanos , Masculino , Mamíferos , Microtúbulos/fisiologia , Microtúbulos/ultraestrutura , Cabeça do Espermatozoide/fisiologia , Cauda do Espermatozoide/fisiologia , Cauda do Espermatozoide/ultraestrutura
15.
Proc Biol Sci ; 288(1952): 20210173, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34074121

RESUMO

The Eocene-Oligocene transition (EOT) represents a period of global environmental changes particularly marked in Europe and coincides with a dramatic biotic turnover. Here, using an exceptional fossil preservation, we document and analyse the diversity dynamics of a mammal clade, Cainotherioidea (Artiodactyla), that survived the EOT and radiated rapidly immediately after. We infer their diversification history from Quercy Konzentrat-Lagerstätte (south-west France) at the species level using Bayesian birth-death models. We show that cainotherioid diversity fluctuated through time, with extinction events at the EOT and in the late Oligocene, and a major speciation burst in the early Oligocene. The latter is in line with our finding that cainotherioids had a high morphological adaptability following environmental changes throughout the EOT, which probably played a key role in the survival and evolutionary success of this clade in the aftermath. Speciation is positively associated with temperature and continental fragmentation in a time-continuous way, while extinction seems to synchronize with environmental change in a punctuated way. Within-clade interactions negatively affected the cainotherioid diversification, while inter-clade competition might explain their final decline during the late Oligocene. Our results provide a detailed dynamic picture of the evolutionary history of a mammal clade in a context of global change.


Assuntos
Fósseis , Mamíferos , Animais , Teorema de Bayes , Evolução Biológica , Europa (Continente) , França , Filogenia
16.
Science ; 372(6548)2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34140356

RESUMO

Echolocation is the use of reflected sound to sense features of the environment. Here, we show that soft-furred tree mice (Typhlomys) echolocate based on multiple independent lines of evidence. Behavioral experiments show that these mice can locate and avoid obstacles in darkness using hearing and ultrasonic pulses. The proximal portion of their stylohyal bone fuses with the tympanic bone, a form previously only seen in laryngeally echolocating bats. Further, we found convergence of hearing-related genes across the genome and of the echolocation-related gene prestin between soft-furred tree mice and echolocating mammals. Together, our findings suggest that soft-furred tree mice are capable of echolocation, and thus are a new lineage of echolocating mammals.


Assuntos
Ecolocação , Roedores/fisiologia , Animais , Evolução Biológica , Osso e Ossos/anatomia & histologia , Quirópteros/anatomia & histologia , Quirópteros/fisiologia , Genoma , Audição/genética , Laringe/anatomia & histologia , Laringe/fisiologia , Mamíferos/anatomia & histologia , Mamíferos/genética , Mamíferos/fisiologia , Roedores/anatomia & histologia , Roedores/genética , Transportadores de Sulfato/genética , Osso Temporal/anatomia & histologia
17.
J Zoo Wildl Med ; 52(2): 427-436, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130384

RESUMO

The Association of Zoos and Aquariums Reproductive Management Center (RMC) in the US and the European Association of Zoos and Aquaria Reproductive Management Group (RMG) in Europe monitor efficacy of contraceptive products in participating institutions and use those results to inform contraceptive recommendations. This study used the joint RMC-RMG Contraception Database to analyze efficacy of deslorelin implants (Suprelorin®), a contraceptive used in a wide range of mammalian taxa. More recently its use has increased in birds and in some reptiles and fish. Deslorelin, a gonadotropin-releasing hormone (GnRH) agonist, stimulates the reproductive system before downregulating receptors on pituitary cells that produce hormones that stimulate gonadal steroids in both males (testosterone) and females (estradiol and progesterone), interrupting sperm production and ovulation, respectively. Nevertheless, it has been used mostly in females. Efficacy has been high in mammals, with failures resulting in offspring in only 1.3% of treated individuals and 0.5% of treatment bouts. The failure rate has been higher in birds, with 14.7% of individuals in 7.2% of bouts producing eggs, perhaps reflecting differences in avian GnRH molecules. Too few reptiles and fish have been treated for meaningful analysis. Although deslorelin appears very safe, a possible exception exists in carnivores, because the stimulatory phase can result in ovulation and subsequent sustained progesterone secretion that may cause endometrial pathology. However, the stimulatory phase can be prevented by treatment with megestrol acetate for 7 d before and 7 d after implant insertion. The two current formulations of Suprelorin are effective for minimums of 6 (4.7 mg) or 12 mo (9.4 mg). The data indicate that Suprelorin is an effective and safe contraceptive option for female mammals, although it may not be effective in males of some mammalian species. Further research is needed to ascertain its usefulness in nonmammalian taxa.


Assuntos
Animais de Zoológico , Anticoncepcionais/administração & dosagem , Pamoato de Triptorrelina/análogos & derivados , Animais , Aves , Coleta de Dados , Implantes de Medicamento , Feminino , Masculino , Mamíferos , América do Norte , Pamoato de Triptorrelina/administração & dosagem
18.
J Exp Biol ; 224(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100541

RESUMO

Giant land vertebrates have evolved more than 30 times, notably in dinosaurs and mammals. The evolutionary and biomechanical perspectives considered here unify data from extant and extinct species, assessing current theory regarding how the locomotor biomechanics of giants has evolved. In terrestrial tetrapods, isometric and allometric scaling patterns of bones are evident throughout evolutionary history, reflecting general trends and lineage-specific divergences as animals evolve giant size. Added to data on the scaling of other supportive tissues and neuromuscular control, these patterns illuminate how lineages of giant tetrapods each evolved into robust forms adapted to the constraints of gigantism, but with some morphological variation. Insights from scaling of the leverage of limbs and trends in maximal speed reinforce the idea that, beyond 100-300 kg of body mass, tetrapods reduce their locomotor abilities, and eventually may lose entire behaviours such as galloping or even running. Compared with prehistory, extant megafaunas are depauperate in diversity and morphological disparity; therefore, turning to the fossil record can tell us more about the evolutionary biomechanics of giant tetrapods. Interspecific variation and uncertainty about unknown aspects of form and function in living and extinct taxa still render it impossible to use first principles of theoretical biomechanics to tightly bound the limits of gigantism. Yet sauropod dinosaurs demonstrate that >50 tonne masses repeatedly evolved, with body plans quite different from those of mammalian giants. Considering the largest bipedal dinosaurs, and the disparity in locomotor function of modern megafauna, this shows that even in terrestrial giants there is flexibility allowing divergent locomotor specialisations.


Assuntos
Dinossauros , Animais , Evolução Biológica , Fenômenos Biomecânicos , Dinossauros/anatomia & histologia , Fósseis , Mamíferos
19.
J Zoo Wildl Med ; 52(2): 638-647, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130407

RESUMO

To determine the diagnostic value of fecal bacterial enteric pathogen cultures (FBEPC) as part of routine preventive medicine protocols in terrestrial mammals housed in a zoological collection, this study investigated the clinical utility of FBEPC results in context of subsequent clinical actions and how its use was rationalized after adjunct use of fecal cytology as a first-line diagnostic tool. Retrospective results (n = 692) that included a routine FBEPC panel of a commercial diagnostic laboratory, including Aeromonas, Salmonella, Campylobacter, Plesiomonas, Shigella, Yersinia, and Edwardsiella, of 417 mammals were organized into preventive (P; n = 485), diagnostic (D; n = 177), or recheck (R; n = 30) samples; for P and D samples, findings were assigned a "clinical significance factor" of 1 to 5 according to culture results and subsequent clinical actions. A score of 3 or higher indicated positive growth of potentially pathogenic bacterial organisms, of which there were 50 FBEPC (P n = 27, D n = 20, R n = 3). The difference in mean clinical significance factor for P versus D samples was significant. Aeromonas spp. were most frequently isolated (n = 32), followed by Salmonella spp. (n = 8) and Plesiomonas shigelloides (n = 8), then Campylobacter spp. (n = 5). There was no growth of Yersinia enterocolitica, Shigella spp., or Edwardsiella spp. In the absence of clinical evidence of gastrointestinal disease, treatment was initiated in only two cases with isolated Campylobacter spp. Implementation of fecal cytology as an initial step in fecal evaluation resulted in a prompt, substantial reduction in number of ordered FBEPC (mean n = 12/month before and n = 5/month after implementation). The findings in this study suggest that FBEPC for these bacterial species has limited value as a screening tool in preventive medicine protocols for the mammalian orders best represented in this study. The use of fecal cytology led to a more targeted and cost-effective use of FBEPC. Fecal cytology as an initial step in preventative and diagnostic testing protocols is recommended.


Assuntos
Animais de Zoológico , Bactérias/isolamento & purificação , Infecções Bacterianas/veterinária , Fezes/microbiologia , Enteropatias/veterinária , Mamíferos , Animais , Bactérias/classificação , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Fezes/citologia , Enteropatias/diagnóstico , Enteropatias/microbiologia , Estudos Retrospectivos
20.
Rev Bras Parasitol Vet ; 30(2): e001921, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133615

RESUMO

Toxoplasma gondii is a zoonotic parasite of worldwide distribution that can infect several species of homeothermic animals. Few studies have evaluated the exposure of captive wild animals to T. gondii. This study involved a serological survey of anti-T. gondii antibodies in mammals kept in Cuba's National Zoo (PZN) and in the Rio de Janeiro Zoo (RIOZOO) in Brazil. The study consisted of a total of 231 serum samples from mammals, 108 from PZN and 123 from RIOZOO. All the samples were subjected to IgG anti-T. gondii testing by means of the inhibition ELISA method and the modified agglutination test, respectively. T. gondii antibodies were detected in 85.2% samples from PZN and 32.5% samples from RIOZOO. At the PZN, Perissodactyla (92.3%) was the order with the highest serological prevalence rate, whereas at the RIOZOO, the order Primates (46.7%) stood out (p<0.05). In addition to this association, the origin of the PZN animals was also associated with T. gondii infection. This finding demonstrates the need for constant veterinary monitoring of captive wild mammals in order to link the serological diagnosis with clinical alterations indicative of toxoplasmosis.


Assuntos
Toxoplasma , Toxoplasmose Animal , Animais , Animais de Zoológico , Anticorpos Antiprotozoários , Brasil/epidemiologia , Cuba/epidemiologia , Mamíferos , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/epidemiologia
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