Animal Embryology Research Articles

Зарубежные стажировки российских зоологов. По материалам эго-документов А. Д. Некрасова

The article presents some aspects of the biography of the famous zoologist, science organizer and one of the first Soviet historians of biology A.D. Nekrasov. The aim of the study was to reconstruct the daily life of scientists at marine biological stations opened in Europe. To realize this goal, it was necessary to study a large array of documentary heritage deposited in the A.D. Nekrasov's fund (f. 48) of the Department of Manuscripts and Rare Books of the Moscow State University Scientific Library. The considered ego-documents of the scientist are introduced into the scientific turnover for the first time and give an idea about the organization of research at marine biological stations and international scientific communications. Nekrasov began his scientific activity at the Moscow University under the guidance of S.A. Zernov, N.Y. Zograf and N.V. Bogoyavlensky. The scientist conducted his hydrobiological research at biological stations in Naples, Saint-Va-la-Hague, Villefranche-Sur-Mer, and later he himself was the initiator of the organization of the biological station of Nizhny Novgorod University on the Pustynskie Lakes. Nekrasov's works were devoted to anatomy, morphology and embryology of animals, hydrobiology, ecology. At the biological stations he got acquainted with outstanding foreign scientists - S. Lo Bianco, E. Perrier, R. Woltereck, G. Kupelwieser. Introduction with the experimental work of European biologists attracted a large number of Russian researchers. At the stations at different times Nekrasov met his countryman - N.K. Koltsov, K.E. Lindeman, V.T. Sheviakov, I.P. Zabusov, M.M. Davydov, P.Y. Garyaev, N.A. Kasyanov. They adopted completely new forms of organization of biological research, experimental methods, studied species diversity of marine fauna, got acquainted with new discoveries of European science. In addition to research and educational component, sea stations pursued cultural goals: artists came here, musical evenings were arranged, a library worked, excursions to nearby cities were organized. Internships at foreign marine stations became an integral feature of Russian zoologists in the late 19th - early 20th centuries and served as an impetus for the creation of similar institutions in Russia.

Ability to compose concept maps and student cognitive learning outcomes in animal embryology and reproductive courses

One of the learning outcomes of learning Animal Embryology and Reproduction is that students can explain concepts about reproduction or embryology theory. Since concept map-based learning can improve students’ critical thinking skills and analysis, and support their interest in learning, this study analysed the ability of students enrolled in the 2019/2020 Animal Embryology and Reproduction course to construct concept maps and students' cognitive learning outcomes through assignments and tests. This descriptive study involved 127 students in semester VI enrolled in the Embryology and Animal Reproduction programme at the Department of Biology Education, FTTE at the Universitas Muhammadiyah Malang. The sampling technique was saturated sampling and the data were collected through the task of compiling concept maps and learning outcomes with tests. The drafting of concept maps was assessed by the concepts and ideas, relationships between concepts, hierarchies, propositions, and spelling, with cognitive learning assessed by tests. The results showed that most students had sufficient ability to compose a concept map and very good learning outcomes, indicating that concept maps can be used to learn biology in Animal Embryology and Reproduction courses.

НАУКОВО-ПЕДАГОГІЧНА ДІЯЛЬНІСТЬ КОЛЕСНИКОВА В. В.

Колесников Володимир Васильович – заслужений діяч науки, доктор біологічних наук, професор. Працював завідувачем кафедри гістології і очолював факультет ветеринарної медицини Одеського сільськогосподарського інституту. Він першим обґрунтував існування підтазового відділу черевної порожнини у деяких представників гризунів і комахоїдних, а також встановив етапи становлення придаткових зовнішніх статевих органів ссавців. В працях по морфології легень науковцем по-новому висвітлена функція бронхіальних шляхів і формування респіраторних відділів на прикладі дихальної системи великої рогатої худоби та коней.

Analysis of Embryology and Reproductive Textbook Needs of Integrated Animal Research Results of Development of Mice Embryos by Providing DEET (Diethyltoluamide)

The purpose of this study was to analyze the needs of the Embryology and Animal Reproduction textbook integrated with the results of research on developing mouse embryos with the support of DEET (Diethyltoluamide). This research is research Descriptive quantitative with a gradual revision defines the Thiagarajan development model. Data collection techniques are done by distributing questionnaires, observations, and interview. The results showed 80% of abstract animal embryology and reproduction materials, 80% of teaching materials were less attractive, 85% were difficult to understand, 80% of images were minimal and 85% were teratologies in developing difficult animals. Analysis of the need for textbooks shows that there is no embryology and animal reproduction textbook as a result of research on developing mouse embryos with the help of DEET (Diethyltoluamide).

Development of Textbooks on Animal Embryology and Reproduction Based on Research Results in the Development of Mice Embryos by Adding DEET (Diethyltoluamide)

The purpose of this study was to develop a textbook on Embryology and Animal Reproduction based on the research on the development of mouse embryos by adding DEET (Diethyltoluamide) that was appropriate and validated by material, media and language experts. This research is a development study of textbooks on animal embryology and reproduction based on the results of research on the development of mouse embryos by adding DEET. The development of this textbook refers to the 4D model developed by Thiagarajan, et al. (1974) which consisted of 4 stages, namely Define, Design, Development, and Disseminate, which were modified to be adapted to this study. This development research produced a textbook on Embryology and Animal Reproduction based on research on the development of mouse embryos by adding proper DEET and validating it by material, media and language experts.

Cellular preservation of excysting developmental stages of new eukaryotes from the early Ediacaran Weng’an Biota

The Ediacaran Weng’an Biota provides a unique window on marine diversity during the interval in which the fundamental animal body plans were being established. Here we describe a previously unreported component of the assemblage, millimeter-scale encysted spheres that exhibit a characteristic but simple slit-shaped excystment mechanism (Sporosphaera guizhouensis n. gen. n. sp.), reminiscent of acritarchs. The cysts contain a large inner body or numerous small discrete membrane-bounded bodies. It is possible that the inner bodies represent disaggregated cells of a multicellular body, like an embryo, but there is no evidence to support this interpretation and the occurrence of the excystment structure is not readily compatible with an embryo interpretation. Rather, we interpret the encysted organisms as multicellular stages within the lifecycle of otherwise probably unicellular eukaryotes. The developmental mode exhibited by Sporosphaera, incorporating a resting stage, implies an adaptation to adverse environmental conditions. This parallels the appearance of Large Ornamented Ediacaran Microfossils (LOEMs) which have been interpreted as diapause stages in the embryology of early animals. Sporosphaera is distinct from LOEMs by ornamentation instead of size, which may implicate that not all LOEMs are animal embryos, if any.

THE USE OF DIFFICULTY LEARNING ASSESSMENT IN ASSESSING THE CONCEPT MASTERY OF BIOLOGY TEACHER CANDIDATES ON DEVELOPMENT STAGE OF ANIMAL EMBRIOLOGY

Abstract This study aims to obtain a description of the mastery of the concept of biology teacher candidates through the study of learning difficulties in the concept of development stage of animal embryo. The subjects of the study were 43 students of semester 6 of academic year 2013 which contracted embryology subjects. The instruments used consist of diagnostic questions (essays and multiple choice questions) and interview format. Data analysis was done quantitatively and qualitatively. The results showed that the mastery of the concept of students on aspects of C1 (remember) is 53% (enough); C2 (understanding) of 77% (good); C3 (applying) of 98% (excellent); And C4 (analyze) of 58% (enough). In addition, some students who experienced difficulty showed a positive response to their learning difficulties. Keywords: Assessment of Learning Difficulties, Concept Mastery, Stages of Animal Embryology Development

The development of CERDAS learning strategy guide for science education students of distance education

Self-regulated learning (SRL) is a part of students’ skills in which they manage, regulate, and monitor their learning process so they can reach their study goal. Students of distance education should comprise this skill. The aim of this research is to describe the development of distance students learning guide, namely “CEDAS strategy” designed for science students. The students’ guidance consists of seven principles, they are; selecting and applying learning strategy appropriately, managing time effectively, planning of learning realistically and accurately, achieving study goal, and doing self-evaluation continuously. The research method was qualitative descriptive. The research involved the students of Universitas Terbuka’ Biology education who participated in Animal Embryology course. The data were collected using a questionnaire and interview. Furthermore, it was analyzed by descriptive analyses. Research finding showed that during try out, most of the students stated that the learning guide was easy to understand, concise, interesting and encouraging for students to continue reading and learning. In the implementation stage, most students commented that the guide is easy to understand, long enough, and helpful so it can be used as a reference to study independently and to apply it in the daily basis.

An Animal Series of Embryological Models in Plaster by Meusel in Germany, circa 1900, probably Representing the Amphioxus

Twenty (20 cm high) models in plaster represented the beginning of the animal embryology. They were mounted on a wooden basis by a metallic wire. All the early models had a polar globule. The first stages of the segmentation were represented with successively : one, two, four, eight, and so on cells, then was a morula and a blastula stage with a cyst and then the gastrulation. At least, three models in a large size represented two hemi‐sections : one (33cm long) was probably an amphioxus larva with three layers dorsally and two ones ventrally ; the other one with ten big somites could be a drosophila sample ; and a frontal cross‐section with the beginning of the organogenesis. A label (L M M) on the basis corresponded to Meusel, a german craftsman which was active during two or three decades after 1900.These models could be the representation of the first embryological stages in the amphioxus or in a sea urchin which were largely studied in these times. Unfortunately the embryology even for its morphological aspects has made so much progress that these models have now only an historical interest and no more a teaching one.Support or Funding InformationBrieux‐Gillot Scientific Library, 48 rue Jacob, Paris 6th. France

Cell signalling during blastocyst morphogenesis.

Blastocyst morphogenesis is prepared for even before fertilisation. Information stored within parental gametes can influence both maternal and embryonic gene expression programmes after egg activation at fertilisation. A complex network of intrinsic, cell-cell mediated and extrinsic, embryo-environment signalling mechanisms operates throughout cleavage, compaction and cavitation. These signalling events not only ensure developmental progression, cell differentiation and lineage allocation to inner cell mass (embryo proper) and trophectoderm (future extraembryonic lineages) but also provide a degree of developmental plasticity ensuring survival in prevailing conditions by adaptive responses. Indeed, many cellular functions including differentiation, metabolism, gene expression and gene expression regulation are subject to plasticity with short- or long-term consequences even into adult life. The interplay between intrinsic and extrinsic signals impacting on blastocyst morphogenesis is becoming clearer. This has been best studied in the mouse which will be the focus of this chapter but translational significance to human and domestic animal embryology will be a focus in future years.

Vitrification in human and domestic animal embryology: work in progress

According to the analysis of papers published in major international journals, rapidly increasing application of vitrification is one of the greatest achievements in domestic animal and especially human embryology during the first decade of our century. This review highlights factors supporting or hampering this progress, summarises results achieved with vitrification and outlines future tasks to fully exploit the benefits of this amazing approach that has changed or will change many aspects of laboratory (and also clinical) embryology. Supporting factors include the simplicity, cost efficiency and convincing success of vitrification compared with other approaches in all species and developmental stages in mammalian embryology, while causes that slow down the progress are mostly of human origin: inadequate tools and solutions, superficial teaching, improper application and unjustified concerns resulting in legal restrictions. Elimination of these hindrances seems to be a slower process and more demanding task than meeting the biological challenge. A key element of future progress will be to pass the pioneer age, establish a consensus regarding biosafety requirements, outline the indispensable features of a standard approach and design fully-automated vitrification machines executing all phases of the procedure, including equilibration, cooling, warming and dilution steps.

John F. Fallon, PhD: Fifty years of excellence in limb research and counting

Passion and thoughtfulness. . . These are an unusual combination of descriptors perhaps, but fitting for the man to whom we dedicate this special issue on limb development, Dr. John F. Fallon. John has approached his work for more than 50 years with a combination of passion and thoughtfulness that has left indelible marks on the field and on the many scientists who have entered or passed through John’s scientific universe. John Fallon was appointed Assistant Professor of Anatomy at the University of Wisconsin-Madison on January 1, 1969, after earning the PhD degree in Biology at Marquette University and serving 2 years on active duty in the US Army Medical Service Corps. He was promoted to Professor of Anatomy in 1981 and had served as a member of the faculty for 41 years upon his retirement on December 21, 2009. During these years, John published 93 peer reviewed original research articles, 20 review articles/book chapters and 4 edited proceedings. Whereas these publications cover a range of topics from the gametes of Nereis limbata to the carapacial ridge of turtles, the majority of John’s contributions are in the field of limb development, a passion he developed in the 1960s as a graduate student in John Saunders’ laboratory at Marquette University. John left his home in Massachusetts when he was thirteen years old and attended high school at Roosevelt Military Academy in Aledo, Illinois. During high school, he became very interested in philosophy and entered Marquette University to pursue undergraduate studies in this subject, also working as a window and awning salesman during college to pay for his education. By his senior year of college, John was completing Bachelor’s degrees in both Philosophy and Zoology, and had applied, and was accepted, to pursue graduate studies in the Philosophy department at Marquette. It was also during his senior year, that John enrolled in a Cell Biology course, which was taught by Dr. John Saunders. He was riveted by Dr. Saunders’ teaching style and approached Dr. Saunders after a class one day and asked whether he might work in his laboratory during his senior year. This turned out to be a career-altering event (Fig. 1). John spent the first several months washing glassware, but he was allowed to watch, and sometimes assist, Mary Gasseling as she was performing some of the very first experiments on the function of the cell death and what would become the zone of polarizing activity in the chick limb. John was hooked! Toward the end of his senior year, he decided that he no longer was interested in pursuing philosophy, but instead wanted to turn his attention to biology. Dr. Saunders personally intervened on John’s behalf to permit a change in departments for his graduate admission in Biology. During his years under Dr. Saunders’ tutelage, John was allowed to spend a few summers at Woods Hole, times that John considers transformative. He published his first paper on collaborative work done there with Dr. C.R. ‘Bunny’ Austin (the Charles Darwin Professor of Animal Embryology, University of Cambridge, UK) using electron microscopy, and recalls his anxiety at the first formal presentation on this work, where he talked about how jelly was released fromNereis limbata eggs during fertilization when the sperm makes contact with the egg. This work tested theories put forth by Drs. Alex Novikoff and Donald Costello who were both present at D ev el op m en ta l D yn am ic s

Origins of techniques in human and animal embryology

Increasingly innovative and imaginative techniques are being developed to investigate the development of animal and human embryos. Among the types of techniques that have been developed are ones that deal with oocyte maturation and culture, the isolation and utilization of stem cells, cryopreservation of reproductive cells and tissues, and various procedures to manipulate early embryos. To appreciate the derivation of these sophisticated techniques, it seems appropriate to consider the very early origins of these current techniques.

Highly efficient vitrification for cryopreservation of human oocytes and embryos: The Cryotop method

Vitrification is frequently referred to as a novel technology of cryopreservation in embryology, although some young embryologists were born after its first successful application. Unfortunately, in spite of the accumulated evidence regarding its enormous potential value, most domestic animal and human laboratories use exclusively the traditional slow-rate freezing with its compromised efficiency and inconsistency. The purpose of this paper is to clarify terms and conditions, to summarize arguments supporting or disapproving the use of vitrification, and to outline its role among assisted reproductive technologies. To provide evidence for the potential significance of vitrification, achievements with the Cryotop technology, an advanced version of the “minimal volume approaches” is analyzed. This technology alone has resulted in more healthy babies after cryopreservation of blastocysts than any other vitrification technique, and more successful human oocyte vitrification resulting in normal births than any other cryopreservation method. The value of this method is also demonstrated by achievements in the field of domestic animal embryology. A modification of the technique using a hermetically sealed container for storage may help to eliminate potential dangers of disease transmission and open the way for widespread application for cryopreservation at all phases of oocyte and preimplantation embryo development in mammals.

Synchrotron X-ray tomographic microscopy of fossil embryos

Fossilized embryos from the late Neoproterozoic and earliest Phanerozoic have caused much excitement because they preserve the earliest stages of embryology of animals that represent the initial diversification of metazoans. However, the potential of this material has not been fully realized because of reliance on traditional, non-destructive methods that allow analysis of exposed surfaces only, and destructive methods that preserve only a single two-dimensional view of the interior of the specimen. Here, we have applied synchrotron-radiation X-ray tomographic microscopy (SRXTM), obtaining complete three-dimensional recordings at submicrometre resolution. The embryos are preserved by early diagenetic impregnation and encrustation with calcium phosphate, and differences in X-ray attenuation provide information about the distribution of these two diagenetic phases. Three-dimensional visualization of blastomere arrangement and diagenetic cement in cleavage embryos resolves outstanding questions about their nature, including the identity of the columnar blastomeres. The anterior and posterior anatomy of embryos of the bilaterian worm-like Markuelia confirms its position as a scalidophoran, providing new insights into body-plan assembly among constituent phyla. The structure of the developing germ band in another bilaterian, Pseudooides, indicates a unique mode of germ-band development. SRXTM provides a method of non-invasive analysis that rivals the resolution achieved even by destructive methods, probing the very limits of fossilization and providing insight into embryology during the emergence of metazoan phyla.

Société Française d’Orthopédie Pédiatrique: Génétique et orthopédie: gènes impliqués dans les malformations congénitales des membres

Limb malformations are frequent. These malformations are isolated or associated with anomalies of other developmental fields and accurate diagnostic is essential for prognosis evaluation, treatment and genetic counseling. Animal embryology and molecular biology techniques, have given us a better understanding of the processes of growth and patterning of the limb buds. The key genes that are involved in these processes have been identified and their interactions recognized. Human genetics has been able to identify, or at least localize, several genes implicated in limb development. We here review the present knowledge on these genes and their mutations responsible for limb anomalies.

Improving cryopreservation systems

Cryopreservation of oocytes and embryos is a crucial step for widespread practical application of other techniques in domestic animal embryology. However, in contrast to the rapid development of procedures in the eighties and early nineties of the last century, new advancements with profound practical consequences have only been recently achieved. As a result of a long and controversial development, an alternative group of methods, vitrification, has proved its efficiency and practicality in the past few years. The aim of this short review is to characterize strategies to prevent cryoinjuries, summarize the development of vitrification, overview its recent achievements, and provide a perspective about possible application. Authors strongly believe that the future of mammalian oocyte and embryo cryopreservation will be mainly based on vitrification, and the rate of advancement will be determined by the rate by which embryologists learn and acknowledge this new approach.

Advancements in cryopreservation of domestic animal embryos

The development of embryo freezing technologies revolutionized cattle breeding. Since then, advancements in cryobiology, cell biology, and domestic animal embryology have enabled the development of embryo preservation methodologies for our other domestic animal species, including sheep and goats. Recently, technologies have been developed to cryopreserve pig embryos, notorious for their extreme sensitivity to cooling; horse embryo cryopreservation is in its infancy. While cryopreservation can enhance the utilization of in vitro embryo production technologies, cryosurvival of in vitro-produced (IVP) or micromanipulated embryos is less than that of in vivo-derived embryos. This review outlines recent efforts in livestock embryo cryopreservation. In the near future, use of preserved embryos could be a routine breeding alternative for all livestock producers providing 1) preservation methods for maternal germplasm, 2) global genetic transport, 3) increased selection pressure within herds, 4) breeding line regeneration or proliferation, and 5) methodology for genetic rescue.

Cryopreservation of swine embryos: a chilly past with a vitrifying future

Since the development of embryo freezing technologies for cattle in the 1980s, advances in cryobiology, cell biology and embryology of domestic animals have enabled the development of embryo preservation methodology for the pig, notorious for extreme sensitivity to cooling. This review outlines recent efforts to understand the biology of pig embryos as related to their extreme sensitivity to cooling. Cellular analyses and molecular approaches are discussed that have enabled pig embryos to survive cryopreservation and after transfer develop into live offspring with normal fecundity at maturity. In the near future, use of preserved embryos will be a routine breeding alternative for swine producers, providing: preservation methods for maternal germplasm; global genetic transport; increased selection pressure within herds; breeding line regeneration or proliferation; and methodology for genetic resource rescue. It took almost 50 years after the first successful embryo transfer to develop embryo preservation in the pig. Nonetheless, by applying novel methods described herein, rapid progress has been achieved.

Vitrification of the oocytes and embryos of domestic animals

After the first successful application of vitrification for embryo cryopreservation 15 years ago, a rapid application of the method in domestic animal embryology was presumed. However, although the advantages of vitrification (simplicity, cost efficiency, speed of the procedure) were widely acknowledged, its use has been mainly restricted to experimental studies. For commercial embryo transfer purposes, the traditional slow-rate or equilibrium freezing has been used. This review attempts to explain the reasons for this phenomenon and discusses the theoretical and practical differences between the two technologies as well as their commercial prospects. Recent developments that improve the efficiency of vitrification and applications to other reproductive technologies are also summarized. These advances may result in considerable advantage and could lead to widespread application of vitrification in certain areas of domestic animal embryology.