Lysozyme in egg whites of tortoises and turtle. Purification and properties of egg white lysozyme of Trionyx gangeticus Cuvier.

Egg white proteins of three species of tortoises and turtle and of hen have been compared by electrophoretic and immunochemical methods. The proteins lacked similarity in electrophoresis, but tortoise and turtle egg white proteins which did not crossreact with those of the hen showed some cross-reaction among themselves. The occurrence of lysozyme as two allelic variants which were distinguishable in electrophoresis was noted only in the egg white of one of the species of tortoise, namely, Trionyx gangeticus Cuvier. Tortoise lysozyme which showed strong lytic activity toward cell walls of Micrococcus lysodeikticus did not exhibit any cross-reaction with hen lysoyzme. It was purified, crystallized, and found to be homogeneous in sodium dodecyl sulfatepolyacrylamide gel electrophoresis, immunochemical tests, and sedimentation. The physicochemical and enzymatic properties of tortoise lysozyme were found to be strikingly similar to those of hen lysozyme with minor differences which could be due to differences in their primary structure. Its average molecular weight of 15,400 was determined from sedimentation and diffusion coefficient values, Archibald experiment, and amino acid composition. The molecule appeared to undergo pH-dependent expansion at pH 2 and dimerization above pH 5.7. In enzymatic properties, tortoise lysozyme showed a specific activity of 29,000–31,000 units and gave a pH optimum at pH 7.5 and an apparent K_a value of 250 mg· liter^?1. Like hen lysozyme, its activity showed strong ionic strength dependence, weak chitinase activity, susceptibility to inhibition by N-acetyl-glucosamine, and stability toward heat.     

Comparison of the protein composition of the chromatins of several species of vertebrates]

Protein composition of chromatins from the liver of various Vertebrates (frog, turtle, hen and rat) has been compared by the immunological method of double diffusion in gel. It was shown that non-histone chromosomal proteins and histones exhibit evident species specificity.     

Comparative study on vertebrate liver AMP deaminases

Similar activity of AMP deaminase was found in rat, hen, turtle and flounder liver when estimated at high AMP concentration. The enzyme activity was of an order of magnitude higher in frog liver. Simple step by step phosphocellulose column chromatography revealed two forms of AMP deaminase in chicken and flounder liver and one form in the liver of rat and turtle. All enzymes (except for frog liver AMP deaminase) were activated by ATP. The enzymes from rat, frog and both forms from flounder were also activated by ADP. GTP exhibited a variety of effects. The enzyme from rat and turtle was inhibited, both forms from hen and flounder were activated and frog liver enzyme was not influenced.     

Common egg envelope antigens are limited to the animal class

The antigens of the egg envelope (zona pellucida) in mammals are of special interest because of their possible involvement in immunoinfertility and as candidate targets for immunocontraception. Conserved zona epitopes from divergent species may present a suitable source and an animal model for investigation of the above factors. We compared egg envelope antigens from 6 species of vertebrates belonging to 3 different classes in order to demonstrate the existence of shared antigens. Egg envelopes from the trout, carp, turtle, hen, duck and quail were isolated and heat-solubilized. They were tested with rabbit polyclonal antisera against carp, trout and duck egg envelopes by the enzyme-linked immunosorbent assay. The results showed significant cross-reactions among egg envelopes of fish and birds. The examined solubilized preparations did not show cross-reactivity with egg envelopes from any other class, suggesting that divergent species did not share common egg envelope antigens, and that their use may not be appropriate in the investigation of immunoinfertility and immunocontraception in humans.     

The decline of the Turtle Dove: Dietary associations with body condition and competition with other columbids analysed using high‐throughput sequencing

Dietary changes linked to the availability of anthropogenic food resources can have complex implications for species and ecosystems, especially when species are in decline. Here, we use recently developed primers targeting the ITS2 region of plants to characterize diet from faecal samples of four UK columbids, with particular focus on the European turtle dove (Streptopelia turtur), a rapidly declining obligate granivore. We examine dietary overlap between species (potential competition), associations with body condition in turtle doves and spatiotemporal variation in diet. We identified 143 taxonomic units, of which we classified 55% to species, another 34% to genus and the remaining 11% to family. We found significant dietary overlap between all columbid species, with the highest between turtle doves and stock doves (Columba oenas), then between turtle doves and woodpigeons (Columba palumbus). The lowest overlap was between woodpigeons and collared doves (Streptopelia decaocto). We show considerable change in columbid diets compared to previous studies, probably reflecting opportunistic foraging behaviour by columbids within a highly anthropogenically modified landscape, although our data for nonturtle doves should be considered preliminary. Nestling turtle doves in better condition had a higher dietary proportion of taxonomic units from natural arable plant species and a lower proportion of taxonomic units from anthropogenic food resources such as garden bird seed mixes and brassicas. This suggests that breeding ground conservation strategies for turtle doves should include provision of anthropogenic seeds for adults early in the breeding season, coupled with habitat rich in accessible seeds from arable plants once chicks have hatched.     

H-Y Antigen and Sex-Determination in Turtles

H-Y antigen was investigated in 14 turtle species belonging to five different families. In 13 species the female was typed as H-Y antigen positive, only in Chinemys reevesi was the male H-Y antigen positive. Since in all vertebrate species studied till now, the expression of H-Y antigen is strictly correlated with the heterogametic sex, it can be assumed that in turtles both types of sex determining mechanisms are realized, namely the ZZ/ZW-and the XX/XY mechanism; both mechanisms are realized in species belonging to one and the same turtle family. However, most turtle species seem to be endowed with a ZZ/ZW sex determining mechanism.     

广州市花地湾市场龟鳖类调查

通过对广州市花地湾花鸟鱼虫市场贸易龟鳖类进行为期3年27次调查,共记录了9科29属41种或亚种,包括鳖科(Trionychidae)2属2种,两爪鳖科(Carettochelyidae)1属1种,龟科(Emydidae)4属5种,淡水龟科(Geoemydidae)10属18种,侧颈龟科(Chelidae)3属3种,动胸龟科(Kinosternidae)2属3种,鳄龟科(Chelydridae)2属2种,陆龟科(Testudinidae)4属6种,海龟科(Cheloniidae)1属1种。其中,国内龟鳖类共13种,外来物种共28种。受保护种类30种,所占比例达73.17%,部分龟类来源为野外捕捉。大量实体商家转入互联网进行精确营销,尤其是针对高价值的濒危种类,未来将着重对该隐蔽领域进行深入调查。     

太平洋丽龟的生理结构研究

目的研究太平洋丽龟的生理结构及特点,为我国开展海龟保育和科学研究提供参考。方法对1只误捕致死的太平洋丽龟进行解剖,观察其循环系统、消化系统、呼吸系统和泄殖系统并测量记录。结果太平洋丽龟心脏位于胸部正中、稍偏右;食管内壁分布许多锥状突起;小肠长240cm,占整个消化系统管道总长的53.1%,消化道总长与体长的比值（简称肠长比）为5.35;精巢1对,阴茎长30cm,可推断为成年的雄龟。结论太平洋丽龟的生理结构估计与其肉食性有关,这对开展人工驯养繁育和物种保护具有重要意义。     

Relationship between the major phosphorylated metabolic intermediates and oxygen affinity of whole blood in the loggerhead (Caretta caretta) and the Green Sea Turtle (Chelonia mydas) during development.

(1) 2,3-Diphosphoglyceric acid (2,3-DPG) is present in the erythrocytes (RBC) of the 68-day loggerhead turtle embryo and 44-day green sea turtle embryo at levels of 7.4 and 5.5 μmoles/ml of RBC, representing the major organic phosphate during the latter period of embryonic development. (2) Inositol pentaphosphate (IPP) is absent in the red blood cells of the embryos of both the loggerhead and green sea turtle. (3) Near equimolar amounts of 2,3-DPG and IPP are present in the erythrocytes of the adult loggerhead and green sea turtle. The total concentration of these two organic phosphates is approximately 0.75 μmoles/ml of RBC in the adult of both species. (4) There is a switch from embryonic to adult hemoglobin during development of these two species of turtles; the two embryonic bands have identical electrophoretic mobilities, whereas the two adult bands migrate differently on cellulose acetate at pH 8.6. (5) The whole blood oxygen affinity of the adult loggerhead and green sea turtle is 60.3 and 32.6 Torr, respectively. (6) The stripped adult hemoglobins in these two species of turtles show no change in oxygen affinity upon addition of 2,3-DPG, ATP, or IPP. (7) It therefore appears unlikely that whole blood oxygen affinity is controlled by organic phosphate modulation of hemoglobin function in these species of turtles.     

Molecular evidence for a clade of turtles.

Although turtles have been generally grouped with the most primitive reptile species, the origin and phylogenetic relationships of turtles have remained unresolved to date. To confirm the phylogenetic position of turtles in amniotes, we have cloned and determined the cDNA sequences encoding for skink lactate dehydrogenase (LDH)-A and LDH-B, snake LDH-A, and African clawed frog LDH-A; four alpha-enolase cDNA sequences from turtle, alligator, skink, and snake were also cloned and determined. All of these eight cDNA sequences, as well as the previously published LDH-A, LDH-B, and alpha-enolase of mammals, birds, reptiles, and African clawed frog, were analyzed by the phylogenetic tree reconstruction methods of neighbor-joining, maximum parsimony, and maximum likelihood. In the phylogenetic analyses, the turtle was found to be closely related to the alligator. Also, we found that the turtle had diverged after the divergence of squamates and birds. This departs from previous hypotheses of turtle evolution and further suggests that turtles are the latest of divergent reptiles, having been derived from an ancestor of crocodilian lineage within the last 200 million years.     

Isolation and cross‐species amplification of seven microsatellite loci from Emydoidea blandingii

We describe the cloning and characterization of seven microsatellite loci from [CA]‐ and [GA]‐enriched partial genomic libraries of Blanding's turtle, Emydoidea blandingii, and their use in two other species of freshwater turtle, Chrysemys picta and Chelydra serpentina. These loci will be used in a long‐term ecological study of the reproductive success of these co‐occurring freshwater turtle species.     

Seed dispersal by the Florida box turtle (<Emphasis Type="Italic">Terrapene carolina bauri</Emphasis>) in pine rockland forests of the lower Florida Keys,United States

Seed dispersal by animals is one of the most important plant-animal mutualisms, but saurochory, the dispersal of seeds by reptiles, has received little attention. We investigated the role of the Florida box turtle (Terrapene carolina bauri) as a seed dispersal agent in pine rockland forests of the lower Florida Keys and examined the effect of turtle digestion on seed germination. We obtained seeds of 11 species with fleshy fruits and 2 species with non-fleshy fruits (a grass and legume) from the feces of 145 box turtles collected on Key Deer National Wildlife Refuge from 1999 to 2000. We planted the seeds of nine species and germination percentage (percentage of seeds that germinated during the experiment) varied from 10% to 80%. Comparative germination experiments were conducted with Thrinax morrissii, Serenoa repens, and Byrsonima lucida. We compared the germination percentage and germination rate (number of days from planting to seedling emergence) of seeds from three treatments (seeds recovered from feces, control seeds with pulp, and control seeds without pulp) and continued these experiments for up to 2 years. Passage through the box turtle digestive tract greatly enhanced the germination percentage and germination rate of S. repens, but decreased the germination percentage of B. lucida and T. morrissii, and decreased germination rate for T. morrissii. Subsequent destructive seed viability tests revealed that many ungerminated T. morrissii seeds remained viable, suggesting long-term seed dormancy may occur, even after passage through the turtle digestive system. In addition, the proportion of ungerminated seeds which remained viable was greater for seeds recovered from turtle feces than from control seeds with pulp. Furthermore, removal of fleshy pulp either manually or by the turtle digestive system may allow T. morrissii to escape insect predation.     

Theta (RSA) activity in the brain of the turtle.

The existence of a synchronizing system generating theta (RSA) activity of an average frequency of 4 Hz has been demonstrated in the brain of the turtle Testudo Graeca. Three brain structures probably participate in the activity--the septum, amygdala and hippocampus. The septal region seems to play a leading role in this complex--lesions in this region abolished the generation of theta activity in 71% of experiments. This synchronizing system is functionally coupled with the olfactory generator of electrographic respiratory response (ERR), which is brought into activity by nasal air flow. This coupling can play a role in genesis of epileptic electrographic activities not only in the turtle, but also in phylogenetically higher species.     

Electrophysiological properties of spinal motoneurons in the adult turtle

The purpose of this study was to develop a scheme for classifying turtle motoneurons, such that their properties could be compared to those of other vertebrate species, including, in particular, the cat. A 130-cell sample of turtle motoneurons was provisionally classified into four groups (1-4) on the basis of a cluster analysis of the cells' intracellularly recorded input resistance, rheobase, and slope of their stimulus current-spike frequency relation. These measurements, using sharp microelectrodes and an in vitro spinal cord slice preparation, were particularly robust. It is argued that the cat counterpart of our turtle type 1, 2, and 3 motoneurons innervate slow-twitch muscle fibers, fast-twitch-oxidative fibers, and fast-twitch-glycolytic fibers, respectively. Our turtle type 4 motoneuron is thought analogous to a particularly high-threshold cat and human cell that innervates highly fatigable fast-twitch muscle fibers in both species. Our turtle type 1 category may include cells that innervate non-twitch muscle fibers, which are found in other non-mammalian vertebrates. To advance comparative spinal cord neurobiology, the present results invite comparison to the motoneurons of other vertebrate species, which have yet to be subjected to similar or other classification procedures.     

Great Lakes coastal wetland habitat use by seven turtle species: influences of wetland type, vegetation, and abiotic conditions

Great Lakes coastal wetlands are important habitats for turtles but few studies have looked at factors driving community structure in these systems. We evaluated the effects of wetland type, vegetation, and abiotic conditions on turtle communities for 56 wetlands in Lakes Huron, Michigan, and Superior with data collected during the summers of 2000–2008. Overall, 1,366 turtles representing seven species were captured using fyke nets. For the majority of species, catches were highest in drowned river mouth wetlands In addition, turtles tended to be more abundant in water lilies, submersed aquatic vegetation, and cattails compared to bulrush. We also found positive correlations between catches of four of the species as well as total turtle catch and turtle species richness with a human disturbance gradient. These correlations suggest that turtles may be able to utilize coastal wetland areas that are inhospitable to fish because of hypoxic conditions. Our results show the importance Great Lakes coastal wetlands to turtles, and stress the need for managers to take into account turtle populations when preparing conservation and restoration strategies.     

Multiple paternity in loggerhead turtle (Caretta caretta) nests on Melbourne Beach, Florida: a microsatellite analysis

Many aspects of sea turtle biology are difficult to measure in these enigmatic migratory species, and this lack of knowledge continues to hamper conservation efforts. The first study of paternity in a sea turtle species used allozyme analysis to suggest multiple paternity in loggerhead turtle (Caretta caretta) clutches in Australia. Subsequent studies indicated that the frequency of multiple paternity varies from species to species and perhaps location to location. This study examined fine-scale population structure and paternal contribution to loggerhead clutches on Melbourne Beach, FL, USA using microsatellite markers. Mothers and offspring from 70 nests collected at two locations were analysed using two to four polymorphic microsatellite loci. Fine-scale population differentiation was not evident between the sampled locations, separated by 8 km. Multiple paternity was common in loggerhead nests on Melbourne Beach; 22 of 70 clutches had more than one father, and six had more than two fathers. This is the first time that more than two fathers have been detected for offspring in individual sea turtle nests. Paternal genotypes could not be assigned with confidence in clutches with more than two fathers, leaving the question of male philopatry unanswered. Given the high incidence of multiple paternity, we conclude that males are not a limiting resource for this central Florida nesting aggregate.     

Effects of wetland connectivity on overwintering and movement behaviours of Australian freshwater turtles

Freshwater turtles are important consumers in Australian freshwater ecosystems. They serve as scavengers, nutrient regulators, and as food sources and Totems for Traditional Owners throughout Australia. Despite their importance, most Australian freshwater turtle species are declining. The impact of winter wetland drying on turtle populations remains unknown, and winter exposure of hibernating turtles may be an important additional source of mortality. We aimed to examine turtle responses to seasonal and episodic wetland drying in wetlands using acoustic telemetry and active trapping. Wetlands were chosen that spanned a range of hydrological connectivity to the adjacent Edward/Kolety-Wakool River. We found that tagged Emydura macquarii typically exit wetlands disconnected from the adjacent permanent river prior to winter, and overwinter in the river. Female E. macquarii rapidly re-entered ‘home’ wetlands (wetlands in which they were initially tagged) the following spring, whereas males tended to leave the study area, returning occasionally. Although we were not able to evaluate a winter drying event, one of the wetlands experienced partial summer drying. All three local turtle species (E. macquarii, Chelodina expansa, C. longicollis) exited the wetland long before winter drying would have become a potential threat. Our results suggest that turtles in this system may be protected from winter wetland drying because they move to the adjacent permanent river prior to winter. Spending the winter in the river channel reduces the risks of being trapped in a drying wetland as temperatures drop in winter.