The population of the green sea turtle(Chelonia mydas)is under decline,threatened by bycatch and illegal acquisition despite worldwide protection efforts.However,the confiscation of illegally acquired sea turtles coul...The population of the green sea turtle(Chelonia mydas)is under decline,threatened by bycatch and illegal acquisition despite worldwide protection efforts.However,the confiscation of illegally acquired sea turtles could aid in tracking their origin and movement patterns,crucial for effective conservation strategies.Combining satellite tracking and genetic analysis offers an opportunity to investigate the relationship between the origins and migration directions of green sea turtles in the western Pacific.Here,we applied two methods to investigate the spatial ecology of 18 green turtles caught as bycatch in the South China Sea.Our results revealed the genetic origins and diverse movements of the turtles.Bayesian Mixed Stock Analysis(MSA)suggested that these turtles originated from the rookery of the Xisha Islands(49.6%),central Ryukyu(24.6%),NE Borneo(8%),and the Sulu Sea(5.2%),with other rookeries in meagre proportions(<2%each).Satellite tracking showed the ranges of their travel were smaller than the whole contributed rookery range,but diverse.The haplotype diversity of these turtles is high,and CmP19 stands out as both the most frequent and the most diverse haplotype in terms of swimming destinations.These results indicate that the South China Sea is likely an important transportation hub and mating spot for green turtles.Our findings provided evidence for the rehabilitation of these green turtles in the wild and illustrated the complexity of movement during the green turtle’s life history,and the“mixed backgrounds”of the green turtles also highlight the need for joint conservation efforts of neighbouring countries in the South China Sea.展开更多
The Antarctic Paleogene marine fossil record has been the key to reconstructing the evolution of the Weddellian Sea and final dismemberment of Southern Gondwana.In this context,Eocene marine vertebrates from Seymour(M...The Antarctic Paleogene marine fossil record has been the key to reconstructing the evolution of the Weddellian Sea and final dismemberment of Southern Gondwana.In this context,Eocene marine vertebrates from Seymour(Marambio)Island have provided valuable information.We present the first Eocene record of marine reptiles from the southern Atlantic Coast of South America.This corresponds to several postcranial turtle remains represented by a proximal end of the right humerus,three caudal and one thoracic vertebrae,a fragment of the left pubis,and ten ossicles of the dorsal carapace,coming from the Leticia Formation(late-mid Eocene)at Cabo Tiburones,Tierra del Fuego,Argentina.These materials show severalfeatures such as the size and general morphology of the humerus and vertebrae,and the presence of relatively small,irregular,smooth,and unkeeled ossicles,which allow us to assign them to Dermochelyidae indet.Dermochelyids are a cosmopolitan group ofcryptodiran turtles,registered from the late Cretaceous up to the recent,with some physiological-biological peculiarities(e.g.,endothermy and an exclusive jellyfish-based diet)and characterized by the presence of an osseous carapace formed by ossicles.The new finding from the Leticia Formation is an addition to the scarce and extremely fragmentary record of Eocene dermochelyids from the southern seas like those from the La Meseta and Submeseta formations(Antarctica)and the Waihao and Burnside formations(New Zealand).This new information allows us to discuss the presence of these turtles in such high latitudes in the past and its implication in the evolution of the Weddellian fauna.展开更多
Chinese soft-shelled turtles (Trionyx sinens) in culture farms using an artificial warming system in Zhejiang, China, often show typical signs of white-spot disease such as white spots on their bodies, skin lesions,...Chinese soft-shelled turtles (Trionyx sinens) in culture farms using an artificial warming system in Zhejiang, China, often show typical signs of white-spot disease such as white spots on their bodies, skin lesions, anorexia and eventually death. The sick turtles were mostly 5-80 g in weight. A suspected fungal pathogen was isolated from the sick turtles and verified as Paecilomyces lilacinus by sequence analysis of the internal transcribed spacer (ITS) of its ribosomal DNA (rDNA). Detailed morphological examinations were also conducted to confirm the white-spot disease.展开更多
[Objective] This study aimed to isolate and identify the pathogens of soft-shelled turtle fulminant infectious disease,to provide the basis for the prevention and control of aquatic animal diseases.[Method] Commercial...[Objective] This study aimed to isolate and identify the pathogens of soft-shelled turtle fulminant infectious disease,to provide the basis for the prevention and control of aquatic animal diseases.[Method] Commercially available sick soft-shelled turtles were used as experimental materials,to isolate and identify the causative pathogens;pathogenicity test and toxin determination of the isolates were carried out;in addition,hyperimmune serum was prepared and its therapeutic effect was detected.[Result] Nine bacteria were isolated from the livers of sick soft-shelled turtles,including seven Aeromonas sobria strains(JA-1) and two A.caviae strains(JA-2).The median lethal dose(LD50) of JA-1 and JA-2 was 4.3×10^5/ml and 5.5×10^7/ml,respectively;the broth culture supernatant of the two bacteria contains a type of toxin with hemolytic activity,indicating that the soft-shelled turtle fulminant infectious disease is caused by A.sobria and A.caviae.Vaccine was prepared by using the two bacteria and rabbit immunization with immunopotentiator,showing a titer of 1:512 and a cure rate of 100%.[Conclusion] This study laid foundation for the prevention and control of aquatic animal diseases.展开更多
A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle (Pelodiscus sinensis). The...A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle (Pelodiscus sinensis). The turtles (initial mean body weight, (115.52 ± 1.05) g) were fed with three experimental diets, in which 0%, 4.72% and 9.44% BFM protein was replaced by 0%, 3% and 6% FSBM, respectively. Results showed that the feeding rate (FR), specific growth rate (SGR) and feed efficiency ratio (FER) of turtles fed with the diet containing 3% FSBM were not significantly different from the control group (0% FSBM) (P > 0.05). However, FR, SGR and FER of turtles fed with the diet containing 6% FSBM were significantly lower than those of the control group (P < 0.05). No significant differences were observed in the activities of serum glutamic-oxalacetic transaminase and glutamicpyruvic transaminase among dietary treatments (P > 0.05). However, the uric acid concentration in turtles fed with the diet containing 3% or 6% FSBM was significantly lower than that in the control group (P < 0.05). There were no significant differences in the activities of lysozyme, alkaline phosphatase and total superoxide dismutase among dietary treatments (P > 0.05). The results suggested that FSBM could replace 4.72% BFM protein in turtle diets without exerting adverse effects on turtle growth, feed utilization and measured immune parameters.展开更多
The effects of ration level and feeding frequency on digestibility in juvenile soft-shelled turtle, Pelodiscus sinensis, were investigated. Four ration levels 1.5%, 2.5%, 4.0% and satiation (6.0% BW/d) were used. Ap...The effects of ration level and feeding frequency on digestibility in juvenile soft-shelled turtle, Pelodiscus sinensis, were investigated. Four ration levels 1.5%, 2.5%, 4.0% and satiation (6.0% BW/d) were used. Apparent digestibility (AD) of dry matter (DMAD), protein (PAD) and protein real digestibility (PRD) were significantly affected by ration level, but not by feeding frequency when the ration level was similar. However, the feeding frequency affected the AD, DMAD, PAD and PRD significantly when the turtles were fed to satiation. The relationship between fecal protein content (Y) and protein intake (At) can be expressed as a quadric equation: Y=-0.1742+0.1476X-0.0003X^2 (r^2=0.876, n=27, F=93.92, P〈0.01).展开更多
Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis...Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis , to reveal the stress response pattern of tissue Vc during hibernation and contribute basic data for turtle culture. We sampled juvenile soft-shelled turtles at pre-hibernation (17.0°C mud temperature;MT), during hibernation (5.8°C MT) and after arousal (20.1°C MT) in the field. The transcript levels of the gene encoding L-gulonolactone oxidase (GLO), the key enzyme for Vc synthesis, decreased significantly during hibernation. However, GLO activity did not match the GLO transcription patterns and remained stable during hibernation, and showed temperature-dependent kinetic characteristics. Vitamin C levels in the brain, liver, kidney, and spleen (but not muscle) all decreased significantly during hibernation, but recovered to pre-hibernation levels or even higher levels after arousal. The soft-shelled turtle endured 5 months of hibernation with no significant oxidative damage in most tissues, except in the spleen. Splenic Vc was nearly exhausted during hibernation, accompanied by a significantly elevated malonaldehyde (MDA) level. Although the high level of oxidative damage quickly decreased after arousal, the potential tissue damage in the spleen during hibernation might account for the weakened immune capacity of turtles after hibernation.展开更多
Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainabi...Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainability development. The present study was conducted to assess the effects of dietary soy protein concentrate (SPC) on growth, digestive enzymes and target of rapamycin (TOR) signaling pathway of juvenile P. sinensis (4.56 ± 0.09 g). SPC was applied to replace FM protein at 0%, 15%, 30% and 60% (designated as T0, T15, T30 and T60, respectively), and each diet was fed to triplicate groups. The results showed that there was no significant difference in growth performance and feed utilization except of the turtles fed with T60 diet, of which showed poorer daily weight gain and feed conversion rate. The pepsin/trypsin and Na+-K+ ATP-ase activities decreased dramatically when SPC level increased, and lipase activities in liver and intestinal tract also showed decline tendency. However, amylase activities were unaffected. No significant differences were observed in TOR, S6K1 and 4E-BP1 genes mRNA expression level of TOR signaling pathway among the treatments. However, the relative phosphorylated level of these proteins decreased significantly when SPC level increased. The present study indicated that high SPC substitution level would suppress digestive enzymes and TOR signaling pathway proteins phosphorylated level and eventually result in growth reduction of P. sinensis.展开更多
Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryo...Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryonic development and offspring traits in two turtle species, one with parchment-shelled eggs and the other with rigidshelled eggs. Deltamethrin exposure during egg incubation did not affect hatching success and hatchling body size in either species. However, embryonic exposure to deltamethrin resulted in reduced hatchling locomotor performance in the red-eared slider turtle(Trachemys scripta) with parchment-shelled eggs, but not in the Chinese three-keeled pond turtle(Chinemys reevesii) with rigid-shelled eggs. These results suggest that parchment-shelled eggs are likely more vulnerable to deltamethrin than rigid-shelled eggs.展开更多
Morphological changes during the embryonic development of limbs of the green turtle,Chelonia mydas,were studied during the entire period of incubation,using transmission and scanning electron microscopy(TEM and SEM). ...Morphological changes during the embryonic development of limbs of the green turtle,Chelonia mydas,were studied during the entire period of incubation,using transmission and scanning electron microscopy(TEM and SEM). Limb buds were first observed at Stage 2. At that stage,the tip was covered with an apical ectodermal ridge(AER) which began to regress at Stage 6. Associated with AER was the presence of the mesenchymal cells which,consequently,differentiated into muscles,cartilage and bones. The gross features of the skeletal development appeared as a condensation of the cartilaginous structures in the proximal distal region of the limbs. The primordial digits were gradually enclosed by hard keratinized webbed skin. The increase in rate of ossification and skin pigmentation was correlated with the growth of the limbs. The development of the limbs was closely related to the transitional appearance of mucus secretion from the epidermis.展开更多
In the study, a total of 20 red-eared turtles ( half male and half female) were selected to conduct the measurement of liver size and intrahepatic blood flow of red-eared turtles by color Doppler ultrasound. The res...In the study, a total of 20 red-eared turtles ( half male and half female) were selected to conduct the measurement of liver size and intrahepatic blood flow of red-eared turtles by color Doppler ultrasound. The results showed that the fight hepatic lobe could be scanned through the right carotid anterior acoustic win- dow, and the left hepatic lobe could be scanned through the left carotid anterior acoustic window, but the vision would be obstructed by the air in trachea. The liver could also be scanned through the left femoral anterior acoustic window and the fight femoral anterior acoustic window when filling of bladder was good. The correla- tion regression analysis suggested that estimated values of liver showed no linear relationship with weight, the longest back curve and the widest back curve. Through the study, the normal indicators for ultrasound examination of red-eared turtle liver were established, in order to provide a reference for examination of turtle liver.展开更多
During the period August 17-28, 2001, in collaboration with the Provincial Bureau of Oceanography & Fisheries of Guangdong and the South China Institute for Endangered Species, the South China Sea Institute of Oce...During the period August 17-28, 2001, in collaboration with the Provincial Bureau of Oceanography & Fisheries of Guangdong and the South China Institute for Endangered Species, the South China Sea Institute of Oceanology, a CAS affiliate in the city of Guangzhou, conducted a sea turtle satellite tracking project at Haigui Bay (Fig. 1) in the vicinity of Gangkou Town, Huidong County, Guangdong Province.展开更多
A biotelemetry experiment is conducted to study the migrant behavior of green turtles (Chelonia mydas) in South China Sea and acquire the physical environment data. The method in use is to track the post nesting migra...A biotelemetry experiment is conducted to study the migrant behavior of green turtles (Chelonia mydas) in South China Sea and acquire the physical environment data. The method in use is to track the post nesting migrant routes of green turtles through the satellite linked transmitters attached on the back of turtles and the global satellite signal transmitting system of Argos. We obtained the positions of the post nesting migrant routes of three green turtles and environment data, which are important in conservation of green turtles and the research of physical oceanography. Based on the test, the concept, principle and method of biotelemetry are also introduced in this paper with a discussion of the further development of this technique and its applying prospection in future.展开更多
Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because t...Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because their globally endangered status have become the focus of an in-water monitoring program, primarily for green turtles (Chelonia mydas). Preliminary assessment indicated that the TCMP contains an important foraging aggregation of sub-adult green turtles. Since then two additional years of data has been collected; this data was analyzed to assess the health of the turtle population. The data also indicated that the weight was predictable according to carapace width and length and that the population is dominated by larger sub-adults.展开更多
The Jordan's NAP (national action plan) provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turt...The Jordan's NAP (national action plan) provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turtle populations in Jordan range from opportunistic capture to global threats such fishing mortality and from pollution incidents. Jordan's NAP addresses the primary causes of turtle mortality with a series of proposed actions. It includes reducing threats from commercial fisheries, development operations, promoting turtle rescue and rehabilitation along with public awareness activities. It considered also a set of recommendations to reflect the importance of protecting marine turtles in Jordan's Gulf of Aqaba. It includes community participation in conservation, capacity of national agencies to carry out management activities and to enforce legislations. To each priority actions identified in NAP, expected results and performance indicators were defined. Hence, the designation of a level of urgency to each specific priority action allowed a phased approach for implementation, subject to budget and available national capacity. Currently, NAP is performing effectively through an integrated network of national working groups including government and non-governmental organisations and other stakeholders.展开更多
Five species of foraging and breeding sea turtles have been identified in Vietnam, they are Green turtle (Chelonia mydas), Loggerhead turtle (Caretta caretta), Olive ridley turtle (Lepidochelys olivacea), Hawksb...Five species of foraging and breeding sea turtles have been identified in Vietnam, they are Green turtle (Chelonia mydas), Loggerhead turtle (Caretta caretta), Olive ridley turtle (Lepidochelys olivacea), Hawksbill turtle (Eretmochelys imbricata) and Leatherback turtle (Dermochelys coriacea). Among them, with the exception of Loggerhead turtle (Caretta caretta), four species have been being lay eggs on the beaches along the country. However, these populations have been strongly suffered by human activities for decades. The number of foraging and breeding Hawksbill and Leatherback sea turtles has dramatically decreased, and Olive Ridley turtle has almost disappeared on their traditional nesting beaches. Beside the reason of harvesting eggs and nesting turtles by catch or by purpose, the developments in coastal areas where sea turtles laying eggs such as in shrimp aquaculture, tourist resort and residential area developments etc., also contributed to this decline of sea turtles. Despite the fact that the recent raising awareness programs on protection and conservation of the sea turtle were very well done with the participation of many organizations and provinces, this important animals still face the risk of extinction in Vietnam.展开更多
Objective The Early Cretaceous sediments are well-exposed in southern Jilin Province,and yield abundant invertebrate and plant fossils,including the typical EosestheriaEphemeropsis trisetalis-Lycoptera(E-E-L)assembl...Objective The Early Cretaceous sediments are well-exposed in southern Jilin Province,and yield abundant invertebrate and plant fossils,including the typical EosestheriaEphemeropsis trisetalis-Lycoptera(E-E-L)assemblage of the Jehol Biota(Shao Tiequan et al.,2017).However,vertebrate fossils,especially tetrapods,are extremely rare and there is no formal documents on these fossils.Recently,a new fossil site dominated by fishes and turtles has been discovered in the middle part of the展开更多
Nest site selection represents an important reproductive strategy for sea turtles as it can strongly affect the development and survival of the offsprings and the reproductive fitness of the adults. In this study we a...Nest site selection represents an important reproductive strategy for sea turtles as it can strongly affect the development and survival of the offsprings and the reproductive fitness of the adults. In this study we analyzed the nest site selection of loggerhead and leatherback turtles and the factors correlated with that selection at Inhaca Island. The spatial position of the nests was recorded during sea turtles nests monitoring and six nesting seasons were used. Satellite images of Inhaca were used to characterize some of the beach features that might be correlated with nest site selection. Nest distribution analysis revealed that loggerhead turtles tend to spread their nests along the entire beach, but a higher aggregation of nests was evident at the northern most section of the eastern coast. Leatherback turtles tend to nest in a restricted area, with approximately 40% nests at the central sections of the coast. Beach height was the physical variable significantly correlated to loggerhead's nest density (r = 0.309, N = 125, P 〈 0.01) while fin grain particles (specifically 0.125 mm grain size particles) (r = 0.399, N = 125, P 〈 0.01) and organic content (r = 0.218, N = 125, P 〈 0.05) were the variables significantly correlated to leatherback's nest density. No other factors investigated affected nest site selection of either species.展开更多
基金supported by the Society of Entrepreneurs and Ecology,the Aquatic Wildlife Conservation Branch of the China Wildlife Conservation Association,and Ocean Park Hong Kong.
文摘The population of the green sea turtle(Chelonia mydas)is under decline,threatened by bycatch and illegal acquisition despite worldwide protection efforts.However,the confiscation of illegally acquired sea turtles could aid in tracking their origin and movement patterns,crucial for effective conservation strategies.Combining satellite tracking and genetic analysis offers an opportunity to investigate the relationship between the origins and migration directions of green sea turtles in the western Pacific.Here,we applied two methods to investigate the spatial ecology of 18 green turtles caught as bycatch in the South China Sea.Our results revealed the genetic origins and diverse movements of the turtles.Bayesian Mixed Stock Analysis(MSA)suggested that these turtles originated from the rookery of the Xisha Islands(49.6%),central Ryukyu(24.6%),NE Borneo(8%),and the Sulu Sea(5.2%),with other rookeries in meagre proportions(<2%each).Satellite tracking showed the ranges of their travel were smaller than the whole contributed rookery range,but diverse.The haplotype diversity of these turtles is high,and CmP19 stands out as both the most frequent and the most diverse haplotype in terms of swimming destinations.These results indicate that the South China Sea is likely an important transportation hub and mating spot for green turtles.Our findings provided evidence for the rehabilitation of these green turtles in the wild and illustrated the complexity of movement during the green turtle’s life history,and the“mixed backgrounds”of the green turtles also highlight the need for joint conservation efforts of neighbouring countries in the South China Sea.
基金funded by the Agencia Nacional de Promoción Científica y Tecnológica-Proyectos de Investigación Científica y Tecnológica-PICT 2017-0607(to M.Reguero)and PICT 2019-00327(to M.Buono).
文摘The Antarctic Paleogene marine fossil record has been the key to reconstructing the evolution of the Weddellian Sea and final dismemberment of Southern Gondwana.In this context,Eocene marine vertebrates from Seymour(Marambio)Island have provided valuable information.We present the first Eocene record of marine reptiles from the southern Atlantic Coast of South America.This corresponds to several postcranial turtle remains represented by a proximal end of the right humerus,three caudal and one thoracic vertebrae,a fragment of the left pubis,and ten ossicles of the dorsal carapace,coming from the Leticia Formation(late-mid Eocene)at Cabo Tiburones,Tierra del Fuego,Argentina.These materials show severalfeatures such as the size and general morphology of the humerus and vertebrae,and the presence of relatively small,irregular,smooth,and unkeeled ossicles,which allow us to assign them to Dermochelyidae indet.Dermochelyids are a cosmopolitan group ofcryptodiran turtles,registered from the late Cretaceous up to the recent,with some physiological-biological peculiarities(e.g.,endothermy and an exclusive jellyfish-based diet)and characterized by the presence of an osseous carapace formed by ossicles.The new finding from the Leticia Formation is an addition to the scarce and extremely fragmentary record of Eocene dermochelyids from the southern seas like those from the La Meseta and Submeseta formations(Antarctica)and the Waihao and Burnside formations(New Zealand).This new information allows us to discuss the presence of these turtles in such high latitudes in the past and its implication in the evolution of the Weddellian fauna.
基金the Science and Technology Department of Zhejiang Province, China (No. 2004C26026)the Science and Technology Department of Hangzhou City, China (No. 20051322 B33)
文摘Chinese soft-shelled turtles (Trionyx sinens) in culture farms using an artificial warming system in Zhejiang, China, often show typical signs of white-spot disease such as white spots on their bodies, skin lesions, anorexia and eventually death. The sick turtles were mostly 5-80 g in weight. A suspected fungal pathogen was isolated from the sick turtles and verified as Paecilomyces lilacinus by sequence analysis of the internal transcribed spacer (ITS) of its ribosomal DNA (rDNA). Detailed morphological examinations were also conducted to confirm the white-spot disease.
基金Supported by Project of Science and Technology Bureau of Hebei Province(09220402D)~~
文摘[Objective] This study aimed to isolate and identify the pathogens of soft-shelled turtle fulminant infectious disease,to provide the basis for the prevention and control of aquatic animal diseases.[Method] Commercially available sick soft-shelled turtles were used as experimental materials,to isolate and identify the causative pathogens;pathogenicity test and toxin determination of the isolates were carried out;in addition,hyperimmune serum was prepared and its therapeutic effect was detected.[Result] Nine bacteria were isolated from the livers of sick soft-shelled turtles,including seven Aeromonas sobria strains(JA-1) and two A.caviae strains(JA-2).The median lethal dose(LD50) of JA-1 and JA-2 was 4.3×10^5/ml and 5.5×10^7/ml,respectively;the broth culture supernatant of the two bacteria contains a type of toxin with hemolytic activity,indicating that the soft-shelled turtle fulminant infectious disease is caused by A.sobria and A.caviae.Vaccine was prepared by using the two bacteria and rabbit immunization with immunopotentiator,showing a titer of 1:512 and a cure rate of 100%.[Conclusion] This study laid foundation for the prevention and control of aquatic animal diseases.
基金financially supported by the Project of Hangzhou Producing, Study and Researching Cooperation of China (Grant No. 20092632E27)
文摘A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle (Pelodiscus sinensis). The turtles (initial mean body weight, (115.52 ± 1.05) g) were fed with three experimental diets, in which 0%, 4.72% and 9.44% BFM protein was replaced by 0%, 3% and 6% FSBM, respectively. Results showed that the feeding rate (FR), specific growth rate (SGR) and feed efficiency ratio (FER) of turtles fed with the diet containing 3% FSBM were not significantly different from the control group (0% FSBM) (P > 0.05). However, FR, SGR and FER of turtles fed with the diet containing 6% FSBM were significantly lower than those of the control group (P < 0.05). No significant differences were observed in the activities of serum glutamic-oxalacetic transaminase and glutamicpyruvic transaminase among dietary treatments (P > 0.05). However, the uric acid concentration in turtles fed with the diet containing 3% or 6% FSBM was significantly lower than that in the control group (P < 0.05). There were no significant differences in the activities of lysozyme, alkaline phosphatase and total superoxide dismutase among dietary treatments (P > 0.05). The results suggested that FSBM could replace 4.72% BFM protein in turtle diets without exerting adverse effects on turtle growth, feed utilization and measured immune parameters.
基金Project supported by the Scientific and Research Bureau of Shenzhen, China
文摘The effects of ration level and feeding frequency on digestibility in juvenile soft-shelled turtle, Pelodiscus sinensis, were investigated. Four ration levels 1.5%, 2.5%, 4.0% and satiation (6.0% BW/d) were used. Apparent digestibility (AD) of dry matter (DMAD), protein (PAD) and protein real digestibility (PRD) were significantly affected by ration level, but not by feeding frequency when the ration level was similar. However, the feeding frequency affected the AD, DMAD, PAD and PRD significantly when the turtles were fed to satiation. The relationship between fecal protein content (Y) and protein intake (At) can be expressed as a quadric equation: Y=-0.1742+0.1476X-0.0003X^2 (r^2=0.876, n=27, F=93.92, P〈0.01).
基金Supported by the National Natural Science Foundation of China(Nos.31172383,31670419)the Scientific Start-up Funding for Doctors(No.Z109021614 to CHEN B J)of Northwest A&F University
文摘Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis , to reveal the stress response pattern of tissue Vc during hibernation and contribute basic data for turtle culture. We sampled juvenile soft-shelled turtles at pre-hibernation (17.0°C mud temperature;MT), during hibernation (5.8°C MT) and after arousal (20.1°C MT) in the field. The transcript levels of the gene encoding L-gulonolactone oxidase (GLO), the key enzyme for Vc synthesis, decreased significantly during hibernation. However, GLO activity did not match the GLO transcription patterns and remained stable during hibernation, and showed temperature-dependent kinetic characteristics. Vitamin C levels in the brain, liver, kidney, and spleen (but not muscle) all decreased significantly during hibernation, but recovered to pre-hibernation levels or even higher levels after arousal. The soft-shelled turtle endured 5 months of hibernation with no significant oxidative damage in most tissues, except in the spleen. Splenic Vc was nearly exhausted during hibernation, accompanied by a significantly elevated malonaldehyde (MDA) level. Although the high level of oxidative damage quickly decreased after arousal, the potential tissue damage in the spleen during hibernation might account for the weakened immune capacity of turtles after hibernation.
文摘Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainability development. The present study was conducted to assess the effects of dietary soy protein concentrate (SPC) on growth, digestive enzymes and target of rapamycin (TOR) signaling pathway of juvenile P. sinensis (4.56 ± 0.09 g). SPC was applied to replace FM protein at 0%, 15%, 30% and 60% (designated as T0, T15, T30 and T60, respectively), and each diet was fed to triplicate groups. The results showed that there was no significant difference in growth performance and feed utilization except of the turtles fed with T60 diet, of which showed poorer daily weight gain and feed conversion rate. The pepsin/trypsin and Na+-K+ ATP-ase activities decreased dramatically when SPC level increased, and lipase activities in liver and intestinal tract also showed decline tendency. However, amylase activities were unaffected. No significant differences were observed in TOR, S6K1 and 4E-BP1 genes mRNA expression level of TOR signaling pathway among the treatments. However, the relative phosphorylated level of these proteins decreased significantly when SPC level increased. The present study indicated that high SPC substitution level would suppress digestive enzymes and TOR signaling pathway proteins phosphorylated level and eventually result in growth reduction of P. sinensis.
文摘Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryonic development and offspring traits in two turtle species, one with parchment-shelled eggs and the other with rigidshelled eggs. Deltamethrin exposure during egg incubation did not affect hatching success and hatchling body size in either species. However, embryonic exposure to deltamethrin resulted in reduced hatchling locomotor performance in the red-eared slider turtle(Trachemys scripta) with parchment-shelled eggs, but not in the Chinese three-keeled pond turtle(Chinemys reevesii) with rigid-shelled eggs. These results suggest that parchment-shelled eggs are likely more vulnerable to deltamethrin than rigid-shelled eggs.
文摘Morphological changes during the embryonic development of limbs of the green turtle,Chelonia mydas,were studied during the entire period of incubation,using transmission and scanning electron microscopy(TEM and SEM). Limb buds were first observed at Stage 2. At that stage,the tip was covered with an apical ectodermal ridge(AER) which began to regress at Stage 6. Associated with AER was the presence of the mesenchymal cells which,consequently,differentiated into muscles,cartilage and bones. The gross features of the skeletal development appeared as a condensation of the cartilaginous structures in the proximal distal region of the limbs. The primordial digits were gradually enclosed by hard keratinized webbed skin. The increase in rate of ossification and skin pigmentation was correlated with the growth of the limbs. The development of the limbs was closely related to the transitional appearance of mucus secretion from the epidermis.
文摘In the study, a total of 20 red-eared turtles ( half male and half female) were selected to conduct the measurement of liver size and intrahepatic blood flow of red-eared turtles by color Doppler ultrasound. The results showed that the fight hepatic lobe could be scanned through the right carotid anterior acoustic win- dow, and the left hepatic lobe could be scanned through the left carotid anterior acoustic window, but the vision would be obstructed by the air in trachea. The liver could also be scanned through the left femoral anterior acoustic window and the fight femoral anterior acoustic window when filling of bladder was good. The correla- tion regression analysis suggested that estimated values of liver showed no linear relationship with weight, the longest back curve and the widest back curve. Through the study, the normal indicators for ultrasound examination of red-eared turtle liver were established, in order to provide a reference for examination of turtle liver.
基金The test is a research project supported by the CAS sponsored Knowl-edge Innovation Program and Guangdong Province s Bureau of Ocean-ography&Fisheries.Its participants also include Liu Yun,a graduate student at the South China Sea Institute of Oceanology,Chan Kinfung of the Hong Kong Agriculture,Fisheries&Conservation Department,and senior engineer Gu Hexiang of the Haigui Bay Nature Reserve.
文摘During the period August 17-28, 2001, in collaboration with the Provincial Bureau of Oceanography & Fisheries of Guangdong and the South China Institute for Endangered Species, the South China Sea Institute of Oceanology, a CAS affiliate in the city of Guangzhou, conducted a sea turtle satellite tracking project at Haigui Bay (Fig. 1) in the vicinity of Gangkou Town, Huidong County, Guangdong Province.
文摘A biotelemetry experiment is conducted to study the migrant behavior of green turtles (Chelonia mydas) in South China Sea and acquire the physical environment data. The method in use is to track the post nesting migrant routes of green turtles through the satellite linked transmitters attached on the back of turtles and the global satellite signal transmitting system of Argos. We obtained the positions of the post nesting migrant routes of three green turtles and environment data, which are important in conservation of green turtles and the research of physical oceanography. Based on the test, the concept, principle and method of biotelemetry are also introduced in this paper with a discussion of the further development of this technique and its applying prospection in future.
文摘Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because their globally endangered status have become the focus of an in-water monitoring program, primarily for green turtles (Chelonia mydas). Preliminary assessment indicated that the TCMP contains an important foraging aggregation of sub-adult green turtles. Since then two additional years of data has been collected; this data was analyzed to assess the health of the turtle population. The data also indicated that the weight was predictable according to carapace width and length and that the population is dominated by larger sub-adults.
文摘The Jordan's NAP (national action plan) provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turtle populations in Jordan range from opportunistic capture to global threats such fishing mortality and from pollution incidents. Jordan's NAP addresses the primary causes of turtle mortality with a series of proposed actions. It includes reducing threats from commercial fisheries, development operations, promoting turtle rescue and rehabilitation along with public awareness activities. It considered also a set of recommendations to reflect the importance of protecting marine turtles in Jordan's Gulf of Aqaba. It includes community participation in conservation, capacity of national agencies to carry out management activities and to enforce legislations. To each priority actions identified in NAP, expected results and performance indicators were defined. Hence, the designation of a level of urgency to each specific priority action allowed a phased approach for implementation, subject to budget and available national capacity. Currently, NAP is performing effectively through an integrated network of national working groups including government and non-governmental organisations and other stakeholders.
文摘Five species of foraging and breeding sea turtles have been identified in Vietnam, they are Green turtle (Chelonia mydas), Loggerhead turtle (Caretta caretta), Olive ridley turtle (Lepidochelys olivacea), Hawksbill turtle (Eretmochelys imbricata) and Leatherback turtle (Dermochelys coriacea). Among them, with the exception of Loggerhead turtle (Caretta caretta), four species have been being lay eggs on the beaches along the country. However, these populations have been strongly suffered by human activities for decades. The number of foraging and breeding Hawksbill and Leatherback sea turtles has dramatically decreased, and Olive Ridley turtle has almost disappeared on their traditional nesting beaches. Beside the reason of harvesting eggs and nesting turtles by catch or by purpose, the developments in coastal areas where sea turtles laying eggs such as in shrimp aquaculture, tourist resort and residential area developments etc., also contributed to this decline of sea turtles. Despite the fact that the recent raising awareness programs on protection and conservation of the sea turtle were very well done with the participation of many organizations and provinces, this important animals still face the risk of extinction in Vietnam.
基金supported by the National Natural Science Foundation of China(grants No.41202012 and 41172009)China Geological Survey(grant No.1212011120149)+1 种基金the Project ‘‘111’’,China(grant No.B-06008)Shandong University of Science&Technology Research Fund(grant No.2015TDJH101)
文摘Objective The Early Cretaceous sediments are well-exposed in southern Jilin Province,and yield abundant invertebrate and plant fossils,including the typical EosestheriaEphemeropsis trisetalis-Lycoptera(E-E-L)assemblage of the Jehol Biota(Shao Tiequan et al.,2017).However,vertebrate fossils,especially tetrapods,are extremely rare and there is no formal documents on these fossils.Recently,a new fossil site dominated by fishes and turtles has been discovered in the middle part of the
文摘Nest site selection represents an important reproductive strategy for sea turtles as it can strongly affect the development and survival of the offsprings and the reproductive fitness of the adults. In this study we analyzed the nest site selection of loggerhead and leatherback turtles and the factors correlated with that selection at Inhaca Island. The spatial position of the nests was recorded during sea turtles nests monitoring and six nesting seasons were used. Satellite images of Inhaca were used to characterize some of the beach features that might be correlated with nest site selection. Nest distribution analysis revealed that loggerhead turtles tend to spread their nests along the entire beach, but a higher aggregation of nests was evident at the northern most section of the eastern coast. Leatherback turtles tend to nest in a restricted area, with approximately 40% nests at the central sections of the coast. Beach height was the physical variable significantly correlated to loggerhead's nest density (r = 0.309, N = 125, P 〈 0.01) while fin grain particles (specifically 0.125 mm grain size particles) (r = 0.399, N = 125, P 〈 0.01) and organic content (r = 0.218, N = 125, P 〈 0.05) were the variables significantly correlated to leatherback's nest density. No other factors investigated affected nest site selection of either species.