RESUMO
We presented a comparative study of two species of South American bats, Myotis albescens and Eumops patagonicus, about prenatal development. This study was carried out using 60 specimens, which were measured and photographed, and the embryonic stage was assigned by the staging system for Carollia perspicillata. We observed that the chorionic vesicle showed similarities in the disposition of the extraembryonic membranes, but they differed in characteristics of their yolk sac; in E. patagonicus, it was more glandular than M. albescens. M. albescens presented a well-developed discoid placenta with a caudal antimesometrial position, but E. patagonicus presented a diffuse placenta, which persists until the end of gestation and a discoid placenta in the uterus-tubal junction. In the embryogenesis, early stages, middle stages, and late stages were defined. In the early stage, the embryonic morphology is similar in the two species. The middle stage is characterized by the muzzle and pinna formation, fore and hind limb regionalization, and the formation of the patagium primordium. In the late stage, the overall growth of the embryo occurs. Its fore and hind limbs, patagium, and the typical craniofacial features are configured. We conclude that in early stages of development, the embryonic morphology of M. albescens and E. patagonicus is similar, while in late stages differences are evident; mainly the craniofacial structures and uropatagium configuration characteristics that allow their classification at the family level. Moreover, differences in time of fusion of maxillary and mandibular process were registered. This could be related to the morphology of the muzzle of each species. Anat Rec, 301:1527-1543, 2018. © 2018 Wiley Periodicals, Inc.
Assuntos
Quirópteros/embriologia , Desenvolvimento Embrionário/fisiologia , Membranas Extraembrionárias/embriologia , Animais , Feminino , Placenta/fisiologia , GravidezRESUMO
In vertebrates such as the mouse and the human, primordial germ cells (PGCs) arise at the base of the allantois and are carried to the epithelium of the posterior intestine, to later migrate to the primordial gonads. In the case of bats, almost nothing is known about this process. To clarify the dynamics of PGCs during gonadal morphogenesis in the phyllostomid bat Sturnira lilium, the proteins for the Ddx4, Sox9 and Mis genes were detected in the gonads of embryos at different stages of development. We identified 15 stages (St) of embryonic development in Sturnira lilium. We found that the formation of the genital ridge and the establishment of the undifferentiated gonad take place between stages 11 and 14. The onset of morphological differentiation in the gonad is first detected in the male gonads at St17. The first PGCs in meiosis are detected in the ovary at St19, whereas in the testicles, the PGCs were in mitotic arrest. Structural changes leading to testicular and ovarian development in Sturnira lilium are observed to be similar to those described for the mouse; however, differences will be established concerning the time taken for these processes to occur.
Assuntos
Quirópteros/embriologia , Células Germinativas , Gônadas/embriologia , Morfogênese , Animais , Western Blotting , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Feminino , Imunofluorescência , Camundongos , Microscopia ConfocalRESUMO
An embryonic staging system for Molossus rufus (also widely known as Molossus ater) was devised using 17 reference specimens obtained during the postimplantation period of pregnancy from wild-caught, captive-bred females. This was done in part by comparing the embryos to a developmental staging system that had been created for another, relatively unrelated bat, Carollia perspicillata (family Phyllostomidae). Particular attention was paid to the development of species-specific features, such as wing and ear morphology, and these are discussed in light of the adaptive significance of these structures in the adult. M. rufus can be maintained and bred in captivity and is relatively abundant in the wild. This embryonic staging system will facilitate further developmental studies of M. rufus, a model species for one of the largest and most successful chiropteran families, the Molossidae.
Assuntos
Quirópteros/embriologia , Adaptação Fisiológica , Animais , Quirópteros/anatomia & histologia , Quirópteros/classificação , Quirópteros/fisiologia , Extremidades/embriologia , Feminino , Idade Gestacional , Atividade Motora , Fenótipo , Gravidez , Crânio/embriologia , Especificidade da Espécie , Trinidad e TobagoRESUMO
Rabies transmission by wild animals has not being controlled satisfactorily. One major rabies vector to humans and cattle is the hematophagous vampire bat Desmodus rotundus whose distribution is still increasing in the Americas. Of all of the strategies currently in place to control this vector, none of them are really specific and some have ecological impacts. In the present study we used a naturally occurring phytoestrogen on a small vampire bat colony. After collection, bats were fed bovine blood containing 200 microg coumestrol for a 30-day period. After treatment, gonads were excised and processed for histological evaluation. Data indicate that coumestrol adversely affects gonad histology and has a possible impact on the fertility of both male and female vampire bats.
Assuntos
Quirópteros/embriologia , Controle de Doenças Transmissíveis/métodos , Cumestrol/farmacologia , Fertilidade/efeitos dos fármacos , Raiva/prevenção & controle , Animais , Bovinos , Feminino , Gônadas/citologia , Gônadas/efeitos dos fármacos , Humanos , Masculino , Raiva/veterináriaRESUMO
A total of 41 pregnant Mexican free-tailed bats (Tadarida brasiliensis) were collected from Carlsbad Caverns, New Mexico, and Vickery Cave, Oklahoma, in May and June 1990 and May 1991 for organochlorine pesticide analyses. Residues of p,p'-DDE were detected by gas chromatography in 40 embryos at levels highly correlated with brain concentrations (r = 0.496) but were not correlated mother's body tissues (r = 0.060). Embryonic levels also did not correlate with either embryonic fat content (r = 0.018) or maternal fat content (r = 0.300), suggesting that placental membranes offer only marginal protection for developing embryos against exposure to lipophilic organochlorine pesticides.
Assuntos
Quirópteros/metabolismo , Hidrocarbonetos Clorados , Inseticidas/farmacocinética , Troca Materno-Fetal , Resíduos de Praguicidas/farmacocinética , Animais , Encéfalo/metabolismo , Quirópteros/embriologia , Feminino , New Mexico , Oklahoma , GravidezAssuntos
Diferenciação Celular , Quirópteros/embriologia , Membranas Extraembrionárias/citologia , Animais , Membrana Celular , Citoplasma , Grânulos Citoplasmáticos , Endoderma , Retículo Endoplasmático , Feminino , Glicogênio , Complexo de Golgi , Lipídeos , Mesoderma/citologia , Microscopia Eletrônica , Mitocôndrias , Fagocitose , Gravidez , Trofoblastos , Membrana Vitelina/citologiaRESUMO
In Panama the phyllostomid bat Artibeus jamaicensis is seasonally polyestrous, and young are born in March or April and July or August. Blastocysts conceived after the second birth implant in the uterus but are dormant from September to mid-November, when normal development again resumes.