With their suitable habitats significantly affected by climate change and human activities,most of the seven globally recognized sea turtles are facing endangerment.In order to predict their present and future(2090−21...With their suitable habitats significantly affected by climate change and human activities,most of the seven globally recognized sea turtles are facing endangerment.In order to predict their present and future(2090−2100)potentially suitable habitats,we utilized the MaxEnt model,incorporating occurrence data for various sea turtle species and environmental datasets under current conditions,as well as under two climate scenarios from the Shared Socioeconomic Pathways(SSP1-2.6 and SSP5-8.5).Our findings showed that the key environmental variables,such as temperature and distance from shore predominantly influence the prediction on the potentially suitable habitat for sea turtles.The most highly suitable habitats for sea turtles are predominantly found in the tropical coastal waters bordering continents,including South and North America,Asia,and Australia.Under the climate scenarios of SSP1-2.6 and SSP5-8.5 for 2090−2100,the anticipated loss of potential suitable habitats is expected to surpass any potential gains for all sea turtle species.The Kemp’s ridley sea turtle(Lepidochelys kempii)is especially vulnerable,with its potentially suitable habitat area projected to decrease by 0.43%under SSP1-2.6 scenario to 6.15%under SSP5-8.5 scenario.In contrast,the most resilient Dermochelys coriacea is projected with a reduction of 1.02%under SSP1-2.6 and 0.57%under SSP5-8.5 in its potentially suitable habitat.These varying responses to climate change inferred the necessity for species-specific conservation strategies.However,only 9.9%of the integrated potentially suitable habitat is protected within the World Database on Protected Areas(WDPA),which suggested the extending of WDPA for more efficiency on the sea turtle conservation.展开更多
Inspired by the way sea turtles rely on the Earth’s magnetic field for navigation and locomotion,a novel magnetic soft robotic turtle with programmable magnetization has been developed and investigated to achieve bio...Inspired by the way sea turtles rely on the Earth’s magnetic field for navigation and locomotion,a novel magnetic soft robotic turtle with programmable magnetization has been developed and investigated to achieve biomimetic locomotion patterns such as straight-line swimming and turning swimming.The soft robotic turtle(12.50 mm in length and 0.24 g in weight)is integrated with an Ecoflex-based torso and four magnetically programmed acrylic elastomer VHB-based limbs containing samarium-iron–nitrogen particles,and was able to carry a load more than twice its own weight.Similar to the limb locomotion characteristics of sea turtles,the magnetic torque causes the four limbs to mimic sinusoidal bending deformation under the influence of an external magnetic field,so that the turtle swims continuously forward.Significantly,when the bending deformation magnitudes of its left and right limbs differ,the soft robotic turtle switches from straight-line to turning swimming at 6.334 rad/s.Furthermore,the tracking swimming activities of the soft robotic turtle along specific planned paths,such as square-shaped,S-shaped,and double U-shaped maze,is anticipated to be utilized for special detection and targeted drug delivery,among other applications owing to its superior remote directional control ability.展开更多
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
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
[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
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
People are familiar with modern turtles, but the evolution of turtles remains one of the biggest mysteries in paleontology. The turtle has a unique body form of tetrapods (four-leg vertebrates,or vertebrates except fi...People are familiar with modern turtles, but the evolution of turtles remains one of the biggest mysteries in paleontology. The turtle has a unique body form of tetrapods (four-leg vertebrates,or vertebrates except fishes, such as lizards/crocodiles,birds, and mammals).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
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
Turmeric residue（TR）, containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the e...Turmeric residue（TR）, containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles（SSTs）, Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets： basal diet（the control group, n=160） and an interventional diet supplemented with 10% TR（the TR group, n=160）. Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase（SOD） activity of SST liver by 112.8%, and decreased the malondialdehyde（MDA） content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography（HPLC） analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were（1.69±0.30） and（0.14±0.03） μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.展开更多
Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer（MSL） sys...Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer（MSL） systems treating turtle aquaculture effluent with adding different amounts of sludge. Four MSL systems were constructed with dry weight ratios of sludge with 0%, 5%, 10%, and 20%（MSL 1, MSL 2, MSL 3, and MSL 4, respectively）. The turtle aquaculture effluent had an average chemical oxygen demand（COD）, ammonia nitrogen（NH4^＋-N） and total nitrogen（TN） concentration of 288.4, 213.4, and 252.0 mg/L, respectively. The COD/TN（C/N） ratio was 1.2. The results showed that the four MSL systems could effectively treat the COD, NH4^＋-N, and TN, and MSL 4 showed significantly improved NH4^＋-N removal efficiency, suggesting the potential of sludge addition to improve the turtle aquaculture effluent treatment. The average COD, TN, and NH4^＋-N removal efficiencies of MSL 4 were 70.3%, 66.5%, and 72.7%, respectively. To further interpret the contribution of microorganisms to the removal, the microbial community compositions and diversities of the four MSL systems were measured. Comparisons of the denaturing gradient gel electrophoresis（DGGE） profiles revealed that the amount of nitrifying bacteria and diversity in MSL 4 were higher than those in the other three systems. We concluded that adding 20% of sludge improved the NH4^＋-N removal and stability of the system for nitrification, due to the enrichment of the nitrifying bacteria in MSL 4.展开更多
In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the followi...In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the following six years,no courtship behavior was found occurring in males and no oviposition in females.From 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones; and 2) reducing the stress of living in captivity.As a result of the hormone treatments,courtship behavior and copulation were observed during September and October,2005.However,no courtship displays were seen from the CK males,which were not treated with hormones.Ovulation occurred between December and March,and the correlation was not significant between behavior of ovulation and food intake.Females laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 fertile.Of the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃.展开更多
基金The National Key Research and Development Program of China under contract No.2023YFC2811400.
文摘With their suitable habitats significantly affected by climate change and human activities,most of the seven globally recognized sea turtles are facing endangerment.In order to predict their present and future(2090−2100)potentially suitable habitats,we utilized the MaxEnt model,incorporating occurrence data for various sea turtle species and environmental datasets under current conditions,as well as under two climate scenarios from the Shared Socioeconomic Pathways(SSP1-2.6 and SSP5-8.5).Our findings showed that the key environmental variables,such as temperature and distance from shore predominantly influence the prediction on the potentially suitable habitat for sea turtles.The most highly suitable habitats for sea turtles are predominantly found in the tropical coastal waters bordering continents,including South and North America,Asia,and Australia.Under the climate scenarios of SSP1-2.6 and SSP5-8.5 for 2090−2100,the anticipated loss of potential suitable habitats is expected to surpass any potential gains for all sea turtle species.The Kemp’s ridley sea turtle(Lepidochelys kempii)is especially vulnerable,with its potentially suitable habitat area projected to decrease by 0.43%under SSP1-2.6 scenario to 6.15%under SSP5-8.5 scenario.In contrast,the most resilient Dermochelys coriacea is projected with a reduction of 1.02%under SSP1-2.6 and 0.57%under SSP5-8.5 in its potentially suitable habitat.These varying responses to climate change inferred the necessity for species-specific conservation strategies.However,only 9.9%of the integrated potentially suitable habitat is protected within the World Database on Protected Areas(WDPA),which suggested the extending of WDPA for more efficiency on the sea turtle conservation.
基金supported by National Natural Science Foundation of China(Grant nos.52275290,51905222)Natural Science Foundation of Jiangsu Province(Grant no.BK20211068)+2 种基金Research Project of State Key Laboratory of Mechanical System and Vibration(Grant no.MSV202419)Major Program of National Natural Science Foundation of China(NSFC)for Basic Theory and Key Technology of Tri-Co Robots(Grant no.92248301)Opening project of the Key Laboratory of Bionic Engineering(Ministry of Education),Jilin University(Grant no.KF2023006).
文摘Inspired by the way sea turtles rely on the Earth’s magnetic field for navigation and locomotion,a novel magnetic soft robotic turtle with programmable magnetization has been developed and investigated to achieve biomimetic locomotion patterns such as straight-line swimming and turning swimming.The soft robotic turtle(12.50 mm in length and 0.24 g in weight)is integrated with an Ecoflex-based torso and four magnetically programmed acrylic elastomer VHB-based limbs containing samarium-iron–nitrogen particles,and was able to carry a load more than twice its own weight.Similar to the limb locomotion characteristics of sea turtles,the magnetic torque causes the four limbs to mimic sinusoidal bending deformation under the influence of an external magnetic field,so that the turtle swims continuously forward.Significantly,when the bending deformation magnitudes of its left and right limbs differ,the soft robotic turtle switches from straight-line to turning swimming at 6.334 rad/s.Furthermore,the tracking swimming activities of the soft robotic turtle along specific planned paths,such as square-shaped,S-shaped,and double U-shaped maze,is anticipated to be utilized for special detection and targeted drug delivery,among other applications owing to its superior remote directional control ability.
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.
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.
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.
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People are familiar with modern turtles, but the evolution of turtles remains one of the biggest mysteries in paleontology. The turtle has a unique body form of tetrapods (four-leg vertebrates,or vertebrates except fishes, such as lizards/crocodiles,birds, and mammals).
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Project supported by the National Natural Science Foundation of China(No.31271848)the Foundation of Fuli Institute of Food Science of Zhejiang University(No.KY201404),China
文摘Turmeric residue（TR）, containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles（SSTs）, Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets： basal diet（the control group, n=160） and an interventional diet supplemented with 10% TR（the TR group, n=160）. Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase（SOD） activity of SST liver by 112.8%, and decreased the malondialdehyde（MDA） content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography（HPLC） analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were（1.69±0.30） and（0.14±0.03） μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.
基金supported by the Ministry of Environmental Protection of China(No.2010467014)the Science and Technology Key Plan of Huzhou(No.2011GN19),China
文摘Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer（MSL） systems treating turtle aquaculture effluent with adding different amounts of sludge. Four MSL systems were constructed with dry weight ratios of sludge with 0%, 5%, 10%, and 20%（MSL 1, MSL 2, MSL 3, and MSL 4, respectively）. The turtle aquaculture effluent had an average chemical oxygen demand（COD）, ammonia nitrogen（NH4^＋-N） and total nitrogen（TN） concentration of 288.4, 213.4, and 252.0 mg/L, respectively. The COD/TN（C/N） ratio was 1.2. The results showed that the four MSL systems could effectively treat the COD, NH4^＋-N, and TN, and MSL 4 showed significantly improved NH4^＋-N removal efficiency, suggesting the potential of sludge addition to improve the turtle aquaculture effluent treatment. The average COD, TN, and NH4^＋-N removal efficiencies of MSL 4 were 70.3%, 66.5%, and 72.7%, respectively. To further interpret the contribution of microorganisms to the removal, the microbial community compositions and diversities of the four MSL systems were measured. Comparisons of the denaturing gradient gel electrophoresis（DGGE） profiles revealed that the amount of nitrifying bacteria and diversity in MSL 4 were higher than those in the other three systems. We concluded that adding 20% of sludge improved the NH4^＋-N removal and stability of the system for nitrification, due to the enrichment of the nitrifying bacteria in MSL 4.
基金supported by the National Natural Science Foundation of China(30910103916)the Key Project of Science and Technology Program of Hainan,China(06122)
文摘In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the following six years,no courtship behavior was found occurring in males and no oviposition in females.From 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones; and 2) reducing the stress of living in captivity.As a result of the hormone treatments,courtship behavior and copulation were observed during September and October,2005.However,no courtship displays were seen from the CK males,which were not treated with hormones.Ovulation occurred between December and March,and the correlation was not significant between behavior of ovulation and food intake.Females laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 fertile.Of the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃.
