RESUMEN
The present investigation was aimed at predicting a still (i.e., dead) vs. live embryo within a hatching goose egg by measuring the eggshell cooling rate. For this, we daily measured the temperature (T) values on the shell surface of goose eggs after they were removed from the incubator and during further natural cooling. T was recorded every 0.5 h for further 1.5 h of cooling. It was possible to recognize eggs with dead embryos using the combination of T, egg weight (W), and surface area (S). The resultant indicator (TS/W) was called specific temperature index (STI). The mathematical relationship using STI measurements between Days 8-13 facilitated 80 % correct identification of the eggs with dead embryos. Additionally, we derived mathematical dependencies for shell weight (Ws) and thickness (t) by utilizing the values of W, egg volume (V), S, the average T of all measurements taken, as well as the drop in T during 1.5 h of natural cooling. The key advantage of these parameters was their measurement and/or calculation by applying non-destructive methods. The integrated application of these parameters resulted in achieving high calculation accuracy as judged by correlation coefficients of 0.908 for Ws and 0.593 for t. These novel mathematical models have the potential to decrease hatching waste by predicting embryo viability. Our research will add to a toolkit for non-invasive egg assessment that is useful in the poultry industry, research on eggs, and engineering.
Asunto(s)
Cáscara de Huevo , Gansos , Temperatura , Animales , Cáscara de Huevo/fisiología , Gansos/fisiología , Gansos/embriología , Óvulo/fisiología , Modelos BiológicosRESUMEN
1. Melanin distribution typically exhibits a gradient dilution along the dorsal-ventral axis of the body, including in domestic geese. However, the specific genes and molecular mechanisms responsible for this melanin distribution pattern remain incompletely understood.2. The transcriptomic comparisons were conducted at three embryonic stages, specifically on embryonic d 15 (E15), 22 (E22), and 29 (E29), between the pigmented dorsal skin and the depigmented distal foot.3. Differentially expressed genes (DEGs) associated with melanin synthesis were identified, particularly TYR, TYRP1, and EDNRB2, which exhibited significantly higher expression levels in the dorsal skin at E15 and E22. However, expression levels significantly decreased in later stages (E29).4. The ASIP gene showed remarkably high-expression levels in the distal feet compared to the dorsal skin post-E22 stage (log2FC: 5.31/6.88 at E22/E29). Gene Ontology (GO) enrichment analysis detected eight terms associated with melanin synthesis and melanosome formation (p < 0.05), including melanosome membrane (GO: 0033162) and melanin biosynthetic process (GO: 0042438). Additionally, KEGG pathway analysis showed significant enrichment of the melanogenesis pathway (hsa004916) at d 22 (E22).
Asunto(s)
Desarrollo Embrionario , Gansos , Perfilación de la Expresión Génica , Melaninas , Transcriptoma , Animales , Melaninas/metabolismo , Melaninas/genética , Gansos/genética , Gansos/crecimiento & desarrollo , Gansos/embriología , Gansos/metabolismo , Perfilación de la Expresión Génica/veterinaria , Desarrollo Embrionario/genética , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Regulación del Desarrollo de la Expresión GénicaRESUMEN
1. The Wulong goose is a Chinese breed and a source of high-quality meat and eggs. A characteristic of the Wulong goose is that a proportion of the birds do not have eyelids, known as the Huoyon trait.2. Wulong geese exhibiting the Huoyan trait at embryonic stages of 9 days (E9), 12 days (E12) and 14 days (E14) were selected alongside those with normal eyelids for comprehensive transcriptome sequencing. Differentially expressed gene (DEG) and functional enrichment analyses were performed and finally, eight DEG were chosen to verify the accuracy of qPCR sequencing.3. Overall, 466, 962 and 550 DEG were obtained from the three control groups, D9 vs. N9, D12 vs. N12 and D14 vs. N14, respectively, by differential analysis (p < 0.05). CDKN1C, CRH, CROCC and TYSND1 were significantly expressed in the three groups. Enrichment analysis revealed the enrichment of CROCC and TYSND1 in pathways of cell cycle process, endocytosis, microtubule-based process, microtubule organising centre organisation, protein processing and protein maturation. CDKN1C and CRH were enriched in the cell cycle and cAMP signalling pathway.4. Some collagen family genes were detected among the DEGs, including COL3A1, COL4A5, COL4A2 and COL4A1. FREM1 and FREM2 genes were detected in both Huoyan and normal eyelids. There was a significant difference (p < 0.01) in FREM1 expression between ED9 and ED14 in female embryos, but this difference was not observed in male embryos.
Asunto(s)
Gansos , Perfilación de la Expresión Génica , Animales , Gansos/genética , Gansos/embriología , Perfilación de la Expresión Génica/veterinaria , Transcriptoma , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Regulación del Desarrollo de la Expresión Génica , Desarrollo Embrionario/genéticaRESUMEN
In this study, the effects of Goose parvovirus (GPV) infection as well as the possible role of NS1 protein on apoptosis induction in goose embryo fibroblast (GEF) cells were examined. Flow cytometry analysis and TUNEL assays revealed that GPV infection and NS1 transfection induced significant apoptosis in GEF cells compared to what was observed in mock-infected cells. Interestingly, the increase in the rate of apoptosis detected in GPV-infected GEFs was accompanied by an increased viral load in the cells. In addition, the apoptotic pathway was mediated by apoptosis-inducing factors (AIFs) and internal factors that influence the release of AIFs. The results indicated that the mitochondrial membrane potential was decreased, and AIF expression was increased in the nucleus (P < 0.01). Reactive oxygen species (ROS) increased gradually within 48 h (P < 0.001). Cathepsin D activities were also increased (P < 0.05). The results demonstrated that the AIF-mediated pathway is a new mitochondrial apoptotic pathway and that mitochondrial depolarization, ROS content, and cathepsin D activities are the key factors influencing apoptosis in GEF cells.
Asunto(s)
Fibroblastos/virología , Gansos/embriología , Parvovirinae/patogenicidad , Proteínas no Estructurales Virales/farmacología , Animales , Apoptosis , Factor Inductor de la Apoptosis/metabolismo , Factor Inductor de la Apoptosis/farmacología , Catepsina D/metabolismo , Muerte Celular , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/metabolismo , Fibroblastos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Mitocondrias/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The primary feather follicles are universal skin appendages widely distributed in the skin of feathered birds. The morphogenesis and development of the primary feather follicles in goose skin remain largely unknown. Here, the induction of primary feather follicles in goose embryonic skin (pre-induction vs induction) was investigated by de novo transcriptome analyses to reveal 409 differentially expressed genes (DEGs). The DEGs were characterized to potentially regulate the de novo formation of feather follicle primordia consisting of placode (4 genes) and dermal condensate (12 genes), and the thickening of epidermis (5 genes) and dermal fibroblasts (17 genes), respectively. Further analyses enriched DEGs into GO terms represented as cell adhesion and KEGG pathways including Wnt and Hedgehog signaling pathways that are highly correlated with cell communication and molecular regulation. Six selected Wnt pathway genes were detected by qPCR with up-regulation in goose skin during the induction of primary feather follicles. The localization of WNT16, SFRP1 and FRZB by in situ hybridization showed weak expression in the primary feather primordia, whereas FZD1, LEF1 and DKK1 were expressed initially in the inter-follicular skin and feather follicle primordia, then mainly restricted in the feather primordia. The spatial-temporal expression patterns indicate that Wnt pathway genes DKK1, FZD1 and LEF1 are the important regulators functioned in the induction of primary feather follicle in goose skin. The dynamic molecular changes and specific gene expression patterns revealed in this report provide the general knowledge of primary feather follicle and skin development in waterfowl, and contribute to further understand the diversity of hair and feather development beyond the mouse and chicken models.
Asunto(s)
Plumas/embriología , Gansos , Genes del Desarrollo , Folículo Piloso/embriología , Morfogénesis/genética , Piel/embriología , Animales , Embrión de Pollo , Embrión no Mamífero , Desarrollo Embrionario/genética , Plumas/metabolismo , Gansos/embriología , Gansos/genética , Gansos/metabolismo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Genes del Desarrollo/genética , Folículo Piloso/metabolismo , Piel/metabolismoRESUMEN
In order to enrich the Anser cygnoides genome and identify the gene expression profiles of primary and secondary feather follicles development, de novo transcriptome assembly of skin tissues was established by analyzing three developmental stages at embryonic day 14, 18, and 28 (E14, E18, E28). Sequencing output generated 436,730,608 clean reads from nine libraries and de novo assembled into 56,301 unigenes. There were 2,298, 9,423 and 12,559 unigenes showing differential expression in three stages respectively. Furthermore, differentially expressed genes (DEGs) were functionally classified according to genes ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and series-cluster analysis. Relevant specific GO terms such as epithelium development, regulation of keratinocyte proliferation, morphogenesis of an epithelium were identified. In all, 15,144 DEGs were clustered into eight profiles with distinct expression patterns and 2,424 DEGs were assigned to 198 KEGG pathways. Skin development related pathways (mitogen-activated protein kinase signaling pathway, extra-cellular matrix -receptor interaction, Wingless-type signaling pathway) and genes (delta like canonical Notch ligand 1, fibroblast growth factor 2, Snail family transcriptional repressor 2, bone morphogenetic protein 6, polo like kinase 1) were identified, and eight DEGs were selected to verify the reliability of transcriptome results by real-time quantitative PCR. The findings of this study will provide the key insights into the complicated molecular mechanism and breeding techniques underlying the developmental characteristics of skin and feather follicles in Anser cygnoides.
Asunto(s)
Gansos/embriología , Gansos/genética , Piel/embriología , Animales , Desarrollo Embrionario , Plumas , Piel/anatomía & histología , Piel/metabolismo , TranscriptomaRESUMEN
To determine whether geese are susceptible to infection by avian leukosis virus (ALV), 702 serum samples from domestic and foreign goose breeds were screened for p27 antigen as well as being inoculated into DF-1 cell cultures to isolate ALV. Although 5.7% of samples were positive for p27 antigen, reactivity appeared to be non-specific because no ALV was detected in the corresponding DF-1 cultures. To further determine whether geese are susceptible to ALV-J isolated from chickens, ALV-J strain JS09GY7 was artificially inoculated into 10-day-old goose embryos, with one-day-old hatched goslings then screened for p27 antigen and the presence of ALV. In all cases, the results of both tests were negative. Liver tissues from the 1-day-old goslings were screened using a polymerase chain reaction-based assay, which failed to amplify ALV-J gene fragments from any of the samples. Further, no histopathological damage was observed in the liver tissues. ALV-J was further inoculated intraperitoneally into one-day-old goslings, with cloacal swabs samples and plasma samples then collected every 5 days for 30 days. All samples were again negative for the presence of p27 antigen and ALV, and liver tissues from the challenged geese showed no histopathological damage and were negative for the presence of ALV-J gene fragments. Furthermore, p27 antigen detection, PCR-based screening, and indirect immunofluorescence assays were all negative following the infection of goose embryo fibroblasts with ALV-J. Together, these results confirm that virulent chicken-derived ALV-J strains cannot infect geese, and that p27 antigen detection in goose serum is susceptible to non-specific interference.
Asunto(s)
Virus de la Leucosis Aviar/patogenicidad , Leucosis Aviar/virología , Pollos , Gansos , Animales , Leucosis Aviar/inmunología , Virus de la Leucosis Aviar/genética , Virus de la Leucosis Aviar/inmunología , Virus de la Leucosis Aviar/aislamiento & purificación , Pollos/virología , Cloaca/virología , ADN Viral/química , ADN Viral/aislamiento & purificación , Fibroblastos/virología , Técnica del Anticuerpo Fluorescente/veterinaria , Gansos/embriología , Gansos/virología , Hígado/patología , Hígado/virología , Antígeno Nuclear de Célula en Proliferación/sangre , Antígeno Nuclear de Célula en Proliferación/aislamiento & purificación , VirulenciaRESUMEN
The aim of this study was to characterize the embryonic ontogeny of 5-hydroxyindoles and 5-methoxyindoles synthesis pathways in the goose pineal organ. The study was performed on embryos aged 14-28 days, which have been incubated under a 12L:12D cycle. The pineal organs were collected for measurements of indole content by HPLC every 6 h on embryonic day (ED) 14, ED 16, ED 18 and ED 22 or every 2 h on ED 24, ED 26 and ED 28. The level of tryptophan showed no significant changes during development and no day-night variations. The content of 5-hydroxytryptophan increased between ED 14 and ED 26. It was significantly higher during scotophase than during photophase starting from ED 14. The serotonin content was low during the early stages of development (ED 14-ED 18) and prominently increased from ED 20. The serotonin levels also showed day-night differences; however, they were less conspicuous than those of 5-hydroxytryptophan. The changes in the level of 5-hydroxyindole acetic acid were similar to those of serotonin. 5-Hydroxytryptophol was measurable from ED 18. Levels of N-acetylserotonin, which were detectable for the first time on ED 16, prominently increased between ED 22 and ED 28 and showed significant day-night differences from ED 20. Melatonin was detectable from ED 18. Like N-acetylserotonin, its content increased rapidly between ED 22 and ED 28, and from ED 20 showed diurnal variations. 5-Methoxyindole acetic acid and 5-methoxytryptophol occurred at measurable levels from ED 18 and ED 26, respectively. The obtained results showed that embryonic development of indole metabolism in the goose pineal organ starts with the beginning of serotonin synthesis. The processes of serotonin acetylation and 5-hydroxyindoles methylation were turned on later. Diurnal rhythmicity develops very early in the embryonic pineal organ of the goose when the eggs are incubated under a 12 h light: 12 h dark schedule. Two processes are responsible for generation of the diurnal rhythms of 5-hydroxyindoles and 5-methoxyindoles: (i) hydroxylation of tryptophan and (ii) acetylation of serotonin.
Asunto(s)
Vías Biosintéticas , Gansos/metabolismo , Indoles/metabolismo , Glándula Pineal/metabolismo , Aminoácidos/metabolismo , Animales , Biomarcadores , Desarrollo Embrionario , Gansos/embriología , Melatonina/metabolismo , Glándula Pineal/embriologíaRESUMEN
Embryo development and chick quality are influenced by parental genotype, age, nutrition, environment, and flock management. The aim of study was to determine if genotype, age of goose or eggs laid near the onset of egg production vs. eggs laid near the end of reproduction influence the stage of embryo at oviposition. Three experiments were undertaken. To compare genotypes (Experiment 1) 150 eggs were collected from 3-year-old commercial line White Koluda (WK) geese and from two breeds involved in a genetic resources conservation program, Zatorska (Za) and Bilgoraj (Bi). Age comparison (Experiment 2) was conducted with 200 eggs collected from 1-, 2-, 3-, and 4-year-old WK geese. To compare laying periods (Experiment 3), 150 WK eggs were collected at the first week of March and 100 at the second half of June. Eggs were stored for 72 h at 16°C, staged using Eyal-Giladi and Kochav (EGK, Roman numerals) and Hamburger and Hamilton (HH, Arabic numerals) procedures. Experiment 1: Individual breed differences were evident with Stage X EGK embryos comprising 42.4, 33.3, and 38.7% in the eggs examined from the WK, Bi, and Za, respectively. For all breeds combined, 38.8% of the embryos were in Stage X, but in the next order in WK there was stage XI (18.2%), while in geese from the genetic reserve it was stage XIII (Bi - 33.3; Za - 29.0%). Experiment 2: In eggs of 1-, 2-, and 3-year-old WK geese, the majority of embryos (38.7, 32.4 and 42.2%, respectively) were in Stage X. In contrast, in 4-year-old geese the embryos were in Stage XI (36.1%). Experiment 3: In eggs collected in March and in June most of embryos were in Stage X (33.7% and 43.6%, respectively). In addition, more developmentally advanced stages (XI-XIII) were similar in both periods. However, embryos in Stage 2 HH were only observed in eggs collected at the end of laying season. Interestingly, earlier stages (VI-IX) were observed exclusively in the eggs collected in March.
Asunto(s)
Embrión no Mamífero/embriología , Desarrollo Embrionario , Gansos/embriología , Genotipo , Reproducción/fisiología , Factores de Edad , Animales , Gansos/genética , Gansos/fisiología , Oviposición , Factores de TiempoRESUMEN
Embryos from aquatic birds are the primary models for the study of flipper development. While some staging of early embryogenesis in duck have been studied, characterization of the stages of the entire embryonic development period in water birds has not been described. This study aimed to establish a comparison of complete morphological development staging for ducks (Anas platyrhynchos) and geese (Anser cygnoides) with the embryonic staging system by Hamburger and Hamilton (HH) for the chicken (Gallus gallus). Our results show that morphological development in the chicken, duck, and goose are similar in the early stages. The major differences occurred after stage 27 of embryonic development, where the beak shape in ducks and geese was wider and longer than in chickens. In addition, the second and third interdigital webs of the hind limb of the chicken were found to be degraded from stage 31, and eventually vanished at stage 35; however, they were retained in ducks and geese. Rapid physical development occurred in the mid-to-late stages in ducks and geese. To our best knowledge, this is the first description of complete embryonic development for the duck and goose. Establishment of an embryonic staging system for duck and goose provides new models for the study of waterfowl development.
Asunto(s)
Embrión de Pollo/embriología , Patos/embriología , Gansos/embriología , Animales , Pico/embriología , Embrión no Mamífero/embriología , Desarrollo Embrionario , Miembro Posterior/embriologíaRESUMEN
The objective of this study was to evaluate the changes in the goose embryo transcriptome during feather development. RNA-Sequencing (RNA-Seq) was used to find the transcriptome profiles of feather follicles from three stages of embryonic dorsal skin at embryonic day 13, 18, and 28 (E13, E18, E28). The results showed that 3001, 6634, and 13,780 genes were differently expressed in three stages. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that differentially expressed genes (DEGs) in E13 vs. E18 were significantly mapped into the GO term of extracellular structure organization and the pathway of extracellular matrix (ECM)-receptor interaction. In E18 vs. E28, the top significantly mapped into GO term was the single-organism developmental process; the pathway was also the ECM-receptor interaction. DEGs in E13 vs. E28 were significantly mapped into the GO term of the multicellular organismal process and the pathway of cell adhesion molecules. Subsequently, the union of DEGs was categorized by succession cluster into eight profiles, which were then grouped into four ideal profiles. Lastly, the seven genes spatio-temporal expression pattern was confirmed by real-time PCR. Our findings advocate that interleukin 20 receptor subunit alpha (IL20RA), interleukin 6 receptor (IL6R), interleukin 1 receptor type 1 (IL-1R1), Wnt family member 3A (WNT3A), insulin-like growth factor binding protein 3 (IGFBP3), bone morphogenetic protein 7 (BMP7), and secreted-frizzled related protein 2 (SFRP2) might possibly play vital roles in skin and feather follicle development and growth processes.
Asunto(s)
Gansos/genética , Morfogénesis/genética , Organogénesis/genética , Piel/embriología , Piel/metabolismo , Animales , Biología Computacional/métodos , Desarrollo Embrionario/genética , Gansos/embriología , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Ontología de Genes , Redes Reguladoras de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Reproducibilidad de los Resultados , TranscriptomaRESUMEN
The phenomenon of multiple embryos in birds and other oviparous vertebrates is very rare and thus poorly studied. Some populations of wild birds or lines of poultry, including the zatorska goose, may be particularly predisposed to developing monovular twin embryos (MTE). The aim of the study was to investigate the frequency of single yolk twin embryos in the zatorska goose and to establish whether these embryos are generated as a result of polyembryony or other developmental anomalies.Embryopathological analysis, which included identification of the developmental stages of all MTEs at the time of death, was carried out on 1,955 unhatched eggs obtained from 20 pedigree breeding flocks of the zatorska goose. Post-mortem examinations revealed as many as 13 MTEs (0.66% compared to embryonated eggs) at varying developmental stages.The results of genotyping of the microsatellite loci of 7 pairs of twins demonstrated genetic similarity in 6 of them; this suggests that they developed from 1 blastoderm, while differences in 2 loci of 1 pair show that the MTE originates from 2 blastodiscs. Pedigree analysis of the MTEs does not provide evidence that predisposition toward twinning results from the genetic background. However, more frequent MTE occurrence could be seen in eggs stored for more than 8 d. It seems that embryos of the zatorska goose are more susceptible to duplication under special conditions, such as prolonged egg storage.
Asunto(s)
Gansos/embriología , Gemelización Monocigótica , Animales , Especies en Peligro de Extinción , Gansos/genéticaRESUMEN
The aim of this study was to estimate the genetic parameters and inbreeding effect on the fertility, embryo mortality and hatchability traits in the Zatorska goose covered by the animal genetic resources conservation program. The material for this study contains information about results of hatching of 18 863 eggs from 721 dams and 168 sires, laid between 1998-2015. Genetic parameters were estimated based on the threshold animal model by the use of Restricted Maximum Likelihood and Gibbs sampling. The percentage of fertilized eggs ranged yearly between 37-80%. The percentage of embryo mortality was very low, ranging between 4.63-23.73%. The percentage of the hatched goslings from the total number of analyzed eggs was on average 33.18%, and 53.72% from fertilized eggs. On average based on both methods, the heritability estimates of the fertility, embryo mortality and hatchability reached 0.36, 0.07, 0.24 for males and 0.44, 0.11, 0.32 for females. The genetic trend had increasing tendency for fertility and hatchability and was stable for embryo mortality for both sexes. The obtained result shows that the Zatorska goose can be still maintained in the reserves of the local gene pool according to current rules and use in the local market as a breed with good reproductive potential.
Asunto(s)
Gansos/genética , Gansos/fisiología , Pool de Genes , Reproducción/genética , Animales , Femenino , Fertilidad , Fertilización , Gansos/embriología , Endogamia , Masculino , Factores de TiempoRESUMEN
Normal tables provide an objective step-wise description of the morphological development of an embryo. Such tables have been described for the chicken, turkey, quail, and duck embryos, but there is no such staging table for goose embryos. As the goose has one of the longest incubation periods of all the poultry species and embryo mortality during incubation is relatively high, a normal table of goose embryo development would be useful in assessing the morpho-genetic status of the goose embryo before and during incubation. In this study, embryos were isolated from commercial White Koluda goose eggs stored no longer than four days in a cool room (18°C) prior to incubation and after 4, 8, 12, and 16 h of incubation. Embryo staging was based on the normal tables described for the chicken by Eyal-Giladi and Kochav (EGK) and Hamburger and Hamilton (HH). Goose embryos from unincubated eggs were at Stage X and XI EGK and after 16 h of incubation the majority of embryos were between Stages 2 and 4 HH. Our results suggest that while the stage of development of the embryo in the unincubated goose egg is similar to that reported for the chicken, although the diameter of goose embryo is slighter larger. Following incubation, a goose embryo advances more slowly than a chicken embryo up to 16 h of incubation.
Asunto(s)
Desarrollo Embrionario , Gansos/embriología , Animales , Embrión no Mamífero/embriología , Gansos/fisiologíaRESUMEN
Three types of mechanical papillae, i.e., conical, filiform, and hair-like papillae, are present on the tongue in the domestic goose. Within conical papillae, we distinguish three categories: large and small conical papillae on the body and conical papillae on the lingual prominence. The arrangement of mechanical papillae on the tongue in Anseriformes is connected functionally with different feeding mechanisms such as grazing and filter-feeding. The present work aims to determine whether morphology of three types of mechanical papillae in goose at the time of hatching is the same as in an adult bird and if the tongue is prepared to fulfill feeding function. Our results revealed that the primordia of the large conical papillae start to develop during the differentiation stage. The primordia of the small conical papillae and conical papillae of the lingual papillae start to develop during the growth stage. At the end of the growth stage, only large conical papillae, three pairs of small conical papillae, and conical papillae of the lingual prominence have similar arrangement as in an adult bird. The shape and arrangement of the remaining small conical papillae probably will be changed after hatching. During embryonic period, the filiform papillae and hair-like papillae are not formed. The embryonic epithelium that covered the mechanical papillae undergoes transformation leading to the formation of multilayered epithelium. During prehatching stage, epithelium becomes orthokeratinized epithelium. In conclusion, the tongue of the domestic goose after hatching is well prepared only for grazing. The filtration of food from water is limited due to the lack of filiform papillae.
Asunto(s)
Embrión no Mamífero/anatomía & histología , Desarrollo Embrionario , Gansos/embriología , Lengua/anatomía & histología , Animales , Lengua/embriología , Lengua/ultraestructuraRESUMEN
BACKGROUND: Muscovy duck parvovirus (MDPV) is the etiological agent of Muscovy duckling parvoviral disease, which is characterized by diarrhea, locomotive dysfunction, stunting, and death in young ducklings, and causes substantial economic losses in the Muscovy duck industry worldwide. FZ91-30 is an attenuated vaccine strain that is safe and immunogenic to ducklings, but the genomic information and molecular mechanism underlining the attenuation are not understood. METHODS: The FZ91-30 strain was propagated in 11-day-old embryonated goose eggs, and viral particles were purified from the pooled allantoic fluid by differential centrifugation and ultracentrifugation. Single-stranded genomic DNA was extracted and annealed to form double-stranded DNA. The dsDNA digested with NcoI resulted two sub-genomic fragments, which were then cloned into the modified plasmid pBluescript II SK, respectively, generating plasmid pBSKNL and pBSKNR. The sub-genomic plasmid clones were sequenced and further combined to construct the plasmid pFZ that contained the entire genome of strain FZ91-30. The complete genome sequences of strain FM and YY and partial genome sequences of other strains were retrieved from GenBank for sequence comparison. The plasmid pFZ containing the entire genome of FZ91-30 was transfected in 11-day-old embryonated goose eggs via the chorioallantoic membranes route to rescue infectious virus. A genetic marker was introduced into the rescued virus to discriminate from its parental virus. RESULTS: The genome of FZ91-30 consists of 5,131 nucleotides and has 98.9 % similarity to the FM strain. The inverted terminal repeats (ITR) are 456 nucleotides in length, 14 nucleotides longer than that of Goose parvovirus (GPV). The exterior 415 nucleotides of the ITR form a hairpin structure, and the interior 41 nucleotides constitute the D sequence, a reverse complement of the D' sequence at the 3' ITR. Amino acid sequence alignment of the VP1 proteins between FZ91-30 and five pathogenic MDPV strains revealed that FZ91-30 had five mutations; two in the unique region of the VP1 protein (VP1u) and three in VP3. Sequence alignment of the Rep1 proteins revealed two amino acid alterations for FZ91-30, both of which were conserved for two pathogenic strains YY and P. Transfection of the plasmid pFZ in 11-day-old embryonated goose eggs resulted in generation of infectious virus with similar biological properties as compared with the parental strain. CONCLUSIONS: The amino acid mutations identified in the VP1 and Rep1 protein may contribute to the attenuation of FZ91-30 in Muscovy ducklings. Plasmid transfection in embryonated goose eggs was suitable for rescue of infectious MDPV.
Asunto(s)
Gansos/virología , Infecciones por Parvoviridae/veterinaria , Parvovirus/crecimiento & desarrollo , Parvovirus/inmunología , Enfermedades de las Aves de Corral/virología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Patos/virología , Gansos/embriología , Infecciones por Parvoviridae/embriología , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/virología , Parvovirus/genética , Parvovirus/aislamiento & purificación , Enfermedades de las Aves de Corral/embriología , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/patología , Alineación de Secuencia , Análisis de Secuencia de ADN , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/inmunología , Vacunas Virales/genética , Vacunas Virales/inmunologíaRESUMEN
Avian hepadnaviruses are etiological agents of hepatitis B, that has been identified primarily in ducks, and more recently in various avian species. In this paper, 16 hepadnaviruses were detected by polymerase chain reaction (PCR) in the field samples from dead embryos of commercially reared domestic duck and goose. Based on the molecular analysis of the S-protein gene sequences and phylogenetic Neighbor-joining tree, identified viruses were clustered in the same genetic group, indicating no host-related diversity. Both duck and goose-origin hepadnaviruses were grouped within the cluster consisting of "Western-country" and "Chinese" duck hepatitis B (DHBV) isolates, showing more evolutionary distances with other known avian hepadnaviruses. Histopathologically, the lesions observed in the liver tissue from hepadnavirus positive duck and goose embryos varied from low to mild degree of perivascular mononuclear cells and mixed cell infiltrations, followed by mild vacuolar changes. Small focal necrotic changes in the liver parenchyma, and bile ductular proliferation were also found in examined liver samples. Generally, the microscopic findings resemble those described in experimentally infected ducks, while this was the first description of hepadnavirus associated lesions in domestic goose. Although hepadnaviruses are considered to have a very narrow host range, this study showed that domestic ducks and geese are susceptible to infection with genetically almost identical hepadnaviruses, that were likely to produce similar microscopic changes in the liver of both duck and goose embryos. The impact of naturally occurred hepadnavirus infection and possible synergistic interactions with other infectious or non-infectious agents on embryo viability needs further investigation.
Asunto(s)
Patos/virología , Gansos/virología , Infecciones por Hepadnaviridae/veterinaria , Hepadnaviridae/genética , Enfermedades de las Aves de Corral/virología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Patos/embriología , Gansos/embriología , Hepadnaviridae/aislamiento & purificación , Infecciones por Hepadnaviridae/patología , Infecciones por Hepadnaviridae/virología , Hígado/embriología , Hígado/patología , Hígado/virología , Datos de Secuencia Molecular , Filogenia , Enfermedades de las Aves de Corral/patología , Análisis de Secuencia de ADN/veterinariaRESUMEN
Adrenergic control of cardiovascular function is a common component of regulation in embryonic birds studied to date. Our goal was to investigate adrenergic and cholinergic cardiovascular regulation in two goose species, the Canada goose (Branta canadensis) and the related domestic goose (Anser anser domesticus) to determine if these species possess similar regulation during embryonic development. We determined mean arterial pressure (Pm) and heart rate (fH) responses to serial blockade of cholinergic, ß-adrenergic and α-adrenergic receptors in B. canadensis and A. domesticus at 70 and 90% of total incubation (28days). Both species possessed cholinergic and ß-adrenergic tone on fH at 70% of incubation that increased in intensity with development. In addition, a constant α-adrenergic tone on Pm was present in both species. Our findings indicate that these geese species possess both cholinergic and adrenergic cardiovascular regulation providing information needed for speculation regarding the commonalities in the ontogeny of these cardiovascular regulatory elements in birds.
Asunto(s)
Gansos/embriología , Frecuencia Cardíaca , Receptores Adrenérgicos/metabolismo , Receptores Nicotínicos/metabolismo , Animales , Atropina/farmacología , Presión Sanguínea , Membrana Corioalantoides/irrigación sanguínea , Gansos/fisiología , Ácido Láctico/sangre , Antagonistas Muscarínicos/farmacología , Fentolamina/farmacología , Propranolol/farmacología , Especificidad de la EspecieRESUMEN
The general development of the tongue in birds was described by Lillie (1908) in chicken. Bryk et al. (1992) also studied the tongue development in chicken and they observed development of the conical papillae of the body. Our study aims to describe the timing of the development of the tongue morphological features in the domestic goose by using SEM methods. The tongue of the domestic goose is characterized by the widest variety of shape of the particular part of the tongue and mechanical papillae. Results indicated that the formation of the apex, body, lingual prominence, and the root of the tongue take place between the 10th and 19th day of incubation. The tongue elongates rapidly between the 16th and 18th day of incubation. Simultaneously, the median groove appears on the body and the lingual prominence and elongates towards the rostral part of the tongue. The conical papillae of the tongue develop gradually. On the body, the conical papillae develop from the caudal part of the body to the rostral part and on the lingual prominence from the median part of the prominence to the lateral part. Hair-like papillae at the caudal surface of the body of the tongue remain primordial to the end of the incubation. Our studies on the morphogenesis of the tongue in the domestic goose revealed changes in shape of the particular part of the tongue and rapid pace of the formation of mechanical papillae. The tongue is completely develop before hatching and ready to collect food.
Asunto(s)
Gansos/embriología , Lengua/embriología , Lengua/ultraestructura , Animales , Microscopía Electrónica de Rastreo , Factores de TiempoRESUMEN
In birds, downy feather quantity mainly affected by the follicles. Wnt6, a secreted cysteine-rich protein, plays a key role in follicular development as an intercellular signaling molecule. The present study was to investigate the follicle development and Wnt6 polymorphism in Wanxi-white geese, a Chinese indigenous breed. In total, 300 fertilized eggs were hatched. At embryonic stage and on early birth goslings, the diameter and density of follicles from different sites were examined after sectioning and staining. The results showed that the diameter of primary feather follicles in thorax, venter, dorsum and flank had no difference at embryonic stage. In contrast, after birth, thorax and ventral feather follicles had greater diameter than those on dorsum and flank. Similarly, the primary feather follicle density was higher in thorax and venter than in dorsum and flank at embryonic stage. The secondary feather follicle diameter in flank was greater than that in other sites examined. The secondary follicle showed lush growth in E27 with thickest in ventral and thorax. Overall, follicle formed consistently in dorsal and flank, and follicle in thorax and ventral formed in another consistent way. The polymorphism study showed 2 single nucleotide polymorphisms of Wnt6 and 3 genotypes identified. Sequencing revealed two nucleotide transitions, T451C and A466G, which were synonymous mutations causing codons for aspartate and lysine to change from GAU to GAC and from AAA to AAG, respectively. This information about follicle development and Wnt6 polymorphisms would provide potential utilization in marker-assisted selection program for down feather selection.