Abnormal persistence of the chorioallantoic membrane is associated with severe developmental abnormalities in freshwater turtles

2020 ◽  
Vol 98 (3) ◽  
pp. 229-235
Author(s):  
Sarah V. Langer ◽  
Carolyn M. Kapron ◽  
Christina M. Davy

Development in oviparous reptiles requires the correct formation and function of extra-embryonic membranes in the egg. In 2017, we incubated 2583 eggs from five species of freshwater turtle during a long-term ecological study and opened eggs that failed to hatch. We described a previously unreported developmental anomaly: the retention of an extra-embryonic membrane around 7 turtles (1 Spiny Softshell Turtle (Apalone spinifera (Le Sueur, 1827)), 1 Snapping Turtle (Chelydra serpentina (Linnaeus, 1758)), and 5 Northern Map Turtles (Graptemys geographica (Le Sueur, 1817))) that were alive but unhatched >14 days after their clutch mates had emerged. We investigated the association between retention of this membrane and the exhibition of other developmental deformities of varying severity, and we tested whether this novel abnormality was associated with reduced fertility or hatching success in affected clutches. Consultation of ∼150 years of literature suggests that we observed persistence of the chorioallantoic membrane (CAM; also called the chorioallantois). Our data suggest that clutches where at least one turtle exhibits a persistent CAM may also exhibit slightly reduced fertility or hatch success in the rest of the clutch compared with conspecific clutches that do not contain this anomaly. Future research should investigate the factors predicting CAM retention and other developmental abnormalities.

2021 ◽  
Vol 914 (1) ◽  
pp. 012003
Author(s):  
V S Sihombing ◽  
R T Kwatrina ◽  
Y Santosa

Abstract Biodiverse countries such as Indonesia provide the exotic Asiatic Softshell Turtle (Amyda cartilaginea Boddaert 1770) for the wildlife trade. Deciding which trade model is detrimental to species survival in the wild can be a major challenge for Management Authorities (MA) in implementing CITES. The consequences for conservation, long-term use, and livelihoods are uncertain. The study used the CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) trade database. The collection of raw data is based on trade reports for the species of freshwater turtles (testudinidae) for the period 2011 to 2021, export countries from Indonesia, export destinations for all countries and sources of harvested turtles from the wild. This research aims to study the freshwater turtle trading trends over the decade, compare total quotas to actual harvest, and recognize how the precautionary principle is applied in harvesting A. cartilaginea. Harvesting and trading are following the quota regulated under the Indonesian government. However, conservation efforts were less emphasized, so it is feared that there will be a population decline and even extinction in the future, while the population in the wild cannot be ascertained. The larger the harvest quota set and the shorter the harvest period, the larger the natural population that must be available.


2015 ◽  
Vol 129 (1) ◽  
pp. 80 ◽  
Author(s):  
Jordan Catrysse ◽  
Emily Slavik ◽  
Jonathan Choquette ◽  
Ashley E. Leifso ◽  
Christina M. Davy

We report a mass mortality of Northern Map Turtles (Graptemys geographica [LeSueur, 1817]) on the north shore of Lake Erie, Ontario, Canada. Thirty-five dead adult females were recovered from a nesting area over a period of four weeks. Predation and boat strikes were both excluded as potential cause of death, but the actual cause could not be determined because of the poor condition of the carcasses. Other possible explanations for the mortality include poisoning, drowning, and infection with an unidentified pathogen. Mass mortality in long-lived species, such as turtles, can have long-term effects on population growth and is a cause for concern in a species at risk.


BioScience ◽  
2020 ◽  
Vol 70 (7) ◽  
pp. 597-609
Author(s):  
Chantel E Markle ◽  
Paul A Moore ◽  
James M Waddington

Abstract Identifying ecosystems resilient to climate and land-use changes is recognized as essential for conservation strategies. However, wetland ecosystems may respond differently to stressors depending on their successional state and the strength of ecohydrological feedbacks resulting in fluctuations in habitat availability and suitability. Long-term habitat suitability is necessary for the persistence of wetland-dependent species and a key characteristic of climatic refugia. In the present article, we review and synthesize biogeochemical, thermal, ecological, and hydrological feedbacks and interactions that operate within wetlands and, consequently, regulate overwintering suitability for many freshwater turtles and snakes. We propose that understanding the breadth and interconnected nature of processes controlling temperature, dissolved oxygen, and water table position are vital for the conservation of northern reptile populations that depend on wetlands to survive winter conditions. Finally, we suggest that our integrated framework can guide future research and the management of wetland ecosystems in an era of unprecedented change.


2021 ◽  
Vol 19 ◽  
pp. 228080002110649
Author(s):  
Chenyang Lei ◽  
Sheng Mei ◽  
Chun Zhou ◽  
Chen Xia

In humans, the trachea is a conduit for ventilation connecting the throat and lungs. However, certain congenital or acquired diseases may cause long-term tracheal defects that require replacement. Tissue engineering is considered a promising method to reconstruct long-segment tracheal lesions and restore the structure and function of the trachea. Decellularization technology retains the natural structure of the trachea, has good biocompatibility and mechanical properties, and is currently a hotspot in tissue engineering studies. This article lists various recent representative protocols for the generation of decellularized tracheal scaffolds (DTSs), as well as their validity and limitations. Based on the advancements in decellularization methods, we discussed the impact and importance of mechanical properties, revascularization, recellularization, and biocompatibility in the production and implantation of DTS. This review provides a basis for future research on DTS and its application in clinical therapy.


2013 ◽  
Vol 91 (7) ◽  
pp. 451-461 ◽  
Author(s):  
P.J. Baker ◽  
J.P. Costanzo ◽  
J.B. Iverson ◽  
R.E. Lee

Timing of emergence from the natal nest is a variable trait in the life history of turtles. In theory, hatchling turtles that emerge synchronously, within and among nests, should gain a survival advantage over hatchlings that emerge independently. We examined emergence patterns for seven species of freshwater turtles that use a common nesting area in northern Indiana, USA. Hatchlings of four species emerged from the nest exclusively in late summer or early fall. However, hatchlings of three species usually overwintered in the nest chamber and emerged the following spring. Interspecific and intraspecific emergence from the nest was more synchronous in fall than in spring. Mean date of fall emergence from the nest did not vary among species; however, a species-specific pattern of emergence was observed in spring. Midland Painted Turtles (Chrysemys picta marginata Agassiz, 1857) emerged in late March and early April and, on average, these hatchlings left their nests 2 weeks earlier than Northern Map Turtles (Graptemys geographica (Le Sueur, 1817)) and 4 weeks earlier than Red-eared Sliders (Trachemys scripta elegans (Wied-Neuwied, 1839)). Although hatchlings of C. p. marginata are smaller than those of G. geographica and T. s. elegans, presumably they gain a survival or growth advantage by emerging earlier.


Diversity ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 97 ◽  
Author(s):  
Mario F. Garcés-Restrepo ◽  
John L. Carr ◽  
Alan Giraldo

Few long-term demographic studies have been conducted on freshwater turtles of South America, despite the need for this type of inquiry to investigate natural variation and strengthen conservation efforts for these species. In this study, we examined the variation in demography of the Chocoan River Turtle (Rhinoclemmys nasuta) based on a population from an island locality in the Colombian Pacific region between 2005 and 2017. We calculated survival, recapture, and transition probabilities, and the effects of stream substrate and El Niño–Southern Oscillation (ENSO) phases (El Niño, Neutral, La Niña) on these variables using a multi-state model. We found differences in survival probabilities between ENSO phases, likely as a consequence of an increase in flood events. In addition, we found support for survival being greater in muddy streams than rocky streams, possibly because it is easier to escape or hide in mud substrates. Recapture probabilities varied by life stages; differences in the probability of recapture between size classes were associated with the high fidelity to territories by adults. The present increases in frequency and severity of El Niño and La Niña may exacerbate the consequences of climatic regimes on natural populations of turtles by increasing the mortality caused by drastic phenomena such as floods.


2019 ◽  
Vol 132 (2) ◽  
pp. 122-125 ◽  
Author(s):  
Alyson Karson ◽  
Siow Yan Jennifer Angoh ◽  
Christina M. Davy

During summer 2017, we found 19 dead or fatally wounded adult female turtles belonging to three at-risk species at a nesting site on the north shore of Lake Erie, Ontario. Individuals were found flipped onto their carapace, had similar holes in their body cavities, and were eviscerated. Their eggs had also been consumed. Although turtle nest depredation by Raccoons (Procyon lotor) is common, it is unusual for them to target large numbers of gravid turtles within a season. Depredated species included Snapping Turtle (Chelydra serpentina), Northern Map Turtle (Graptemys geographica), and Blanding’s Turtle (Emydoidea blandingii). Our observation represents a spike in additive mortality for these populations, which could have long-term demographic consequences.


2019 ◽  
Vol 4 (1) ◽  
pp. 59-76 ◽  
Author(s):  
Alison E. Fowler ◽  
Rebecca E. Irwin ◽  
Lynn S. Adler

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.


2015 ◽  
Vol 20 (4) ◽  
pp. 242-251 ◽  
Author(s):  
Éva Kállay

Abstract. The last several decades have witnessed a substantial increase in the number of individuals suffering from both diagnosable and subsyndromal mental health problems. Consequently, the development of cost-effective treatment methods, accessible to large populations suffering from different forms of mental health problems, became imperative. A very promising intervention is the method of expressive writing (EW), which may be used in both clinically diagnosable cases and subthreshold symptomatology. This method, in which people express their feelings and thoughts related to stressful situations in writing, has been found to improve participants’ long-term psychological, physiological, behavioral, and social functioning. Based on a thorough analysis and synthesis of the published literature (also including most recent meta-analyses), the present paper presents the expressive writing method, its short- and long-term, intra-and interpersonal effects, different situations and conditions in which it has been proven to be effective, the most important mechanisms implied in the process of recovery, advantages, disadvantages, and possible pitfalls of the method, as well as variants of the original technique and future research directions.


2020 ◽  
Author(s):  
Emily Budzynski-Seymour ◽  
James Steele ◽  
Michelle Jones

Physical activity (PA) is considered essential to overall health yet it is consistently reported that children are failing to meet the recommended levels. Due to the bidirectional relationship between affective states and PA, affective responses are a potential predictor to long term engagement. Since late March 2020 the UK government enforced ‘lockdown’ measures to help control the spread of Coronavirus (COVID-19); however, this has impacted children’s PA. Using online resources at home to support PA is now common. The primary aim of this research was to investigate the use of the Change4Life 10-minute Shake Ups to support PA by examining the effects of Disney branding upon children’s (n=32) post activity affective responses and perceived exertion. The secondary was to investigate the effect of the lockdown on PA habits. Children had similar positive affective responses and perceived effort to activities; however, branding was considered to be a key contributing factor based upon qualitative feedback from parents. Children’s PA levels dropped slightly since ‘lockdown’ was imposed; though online resources have been utilised to support PA. The use of immersive elements such as characters and narrative in PA sessions, as well as utilising online resources during ‘lockdown’ appear potentially promising for future research.


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