Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Turtles”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 847 records · Page 47Linked to original sources

Epidemiologic determinants of aural abscessation in free-living eastern box turtles (Terrapene carolina) in Virginia.

Epidemiologic determinants of 46 cases of aural abscessation in free-living eastern box turtles (Terrapene carolina) admitted to the Wildlife Center of Virginia (Virginia, USA) from 1991 to 2000 were evaluated. County human population density, year and season of admission, weight, and sex did not affect the risk for box turtles to develop aural abscessation. Counties with cases of aural abscessation were not randomly distributed, but rather were clustered into two multi-county regions. Geographic location was the only risk factor associated with aural abscessation in box turtles found in this study. Possible etiologies could include chronic infectious disease, malnutrition, or chronic exposure to environmental contamination with organochlorine compounds.

Abscess↗

An outbreak of salmonellosis linked to a marine turtle.

In September 1998, an outbreak of gastroenteritis occurred in a coastal Aboriginal community in the Northern Territory over a seven day period. An investigation was conducted by the Center for Disease Control, Territory Health Services. Thirty-six cases were detected and 17% (n=6) were hospitalized. Salmonella chester was isolated from eight of nine stool specimens. Sixty-two percent of cases interviewed (n=28) reported consumption of a green turtle (Chelonia mydas) within a median of 24 hours prior to onset of illness. Of the remainder, all but two were contacts of other cases. Salmonella chester was isolated from a section of partially cooked turtle meat. There are no previous published reports of salmonellosis associated with consumption of sea turtles despite them being a popular food source in coastal communities in the Pacific.

Adolescent↗

An analysis of the growth based on the size and age distributions of the hawksbill sea turtle inhabiting Cuban waters.

The first costal scute (C 1) collected from 2, 749 hawksbill turtle (Eretmochelys imbricata) captured in Cuban waters in 1993 and 1994 were analyzed to determine their body size and age distributions. The C 1 width (C 1 W) was converted to the straight carapace length (SCL) using a formula, SCL = 4.3527 (C 1 W)0.8484, to examine its body size distribution. The SCL ranged from 51.3 to 96.1 cm with 68.8 cm of mean and 68.6 cm of median. Ages of captured turtles estimated from the C 1 surface patterns were ranged from 3.3 to 61.5 years old with 15.8 years of mean and 14.5 years of median. A growth function of van Bertalanffy, M(t) = A(1-Be-kt), was applied to determine the relationship between the age and body size (SCL). A formula, SCL = 80.4(1 -0.663e-0.118(Age)), was derived and indicated a slowdown in the growth after about 14 years old. The maturation age and the rate of sexually matured Cuban hawksbill turtles were also discussed based on these results.

Age Distribution↗

Medetomidine-ketamine anesthesia in red-eared slider turtles (Trachemys scripta elegans).

This study evaluated the effects of high and low dosages of medetomidine-ketamine in red-eared slider turtles (Trachemys scripta elegans) and the reversibility of the anesthesia with atipamezole. Thirty healthy adult turtles were assigned randomly to one of two dosage groups. The lower dosage group received 0.1 mg medetomidine/kg body weight intramuscularly (i.m.) combined with 5 mg ketamine/kg i.m. The higher dosage group received 0.2 mg medetomidine/kg i.m. combined with 10 mg ketamine/kg i.m. Physiologic parameters evaluated included heart rate, palpebral reflex, limb and neck relaxation, and cloacal temperature. Responses to minor procedures such as i.m. injection (0.1 ml 0.9% NaCl) and endotracheal intubation also were evaluated. In addition, the higher dosage group was evaluated for responsiveness to a skin incision and placement of a skin suture. Both dosage trials resulted in a level of anesthesia deep enough for performing a physical examination, minor procedures, and endotracheal intubation. The higher dosage produced a level of anesthesia sufficient for performing a skin incision and suture placement. Heart rate and cloacal temperatures remained stable throughout the entire procedure for both groups. Atipamezole was administered i.m. at five times the dose of medetomidine (0.5 mg/kg i.m. or 1 mg/kg i.m.) 60 min after the medetomidine-ketamine was administered. All of the turtles were swimming 60 min after atipamezole administration.

Adrenergic alpha-Agonists↗

The behavioral reactions of a snake and a turtle to abrupt decreases in gravity.

We report here on the behavioral reaction of two reptiles to abrupt decreases in gravity. One striped rat snake, Elaphe quadrivirgata, and three striped-neck pond turtles, Mauremys japonica, were exposed to microgravity on parabolic flight, during the filming of a documentary for the NHK television station in Japan. The video films revealed that the snake reflexively responded to the shift from hyper- to hypogravity by taking up a defensive posture--on the first parabola, the snake struck at itself. The turtles actively extended their limbs and hyper-extended their neck in microgravity, a posture which is identical to the displayed during their contact "righting reflex", when placed upside-down in normal gravity. The aggressive display of the snake was unexpected, although the righting response of the turtles was consistent with that shown by other vertebrates, including fish and mammals, exposed to microgravity. An implication of these observations is that the afferent signal for the righting reflex of vertebrates in normal gravity must be the unloading of ventral receptors in the sensory system, rather than the loading of dorsal receptors. These are the first behavioral records for any reptiles exposed to hypogravity.

Aggression↗

The thrombocyte aggregation process in the turtle Phrynopys hilarii (Chelonia). An ultrastructural study.

This study investigates the thrombocyte aggregation process in the South American fresh water turtle (Phrynopys hilarii) using electron microscopy. Blood was taken from surgically exposed lateral neck vessels of ten turtles Phrynopys hilarii during the spring and summer seasons, when the mean temperature is 37 degrees C. Blood samples were fixed with Karnovsky solution for processing by transmission electron microscopy. The turtle thrombocytes were spindle-shaped with lobulated nuclei. Prominent vesicles and canaliculi were found throughout the cytoplasm. The cytoplasm organelles showed an agranular endoplasmatic reticulum, Golgi complex near the centrioles and scattered free ribosomes. These cells are similar to bird thrombocytes but distinct from fish and frog thrombocytes. Blood clotting time was 5 min +/- 30 sec measured by the Lee and White method. Structural alterations resulting from the aggregation process occurred after activation. Thrombocytes developed numerous filopodial projections, an increased number of vacuoles and changed from spindle to spherical shape. P. hilarii thrombocytes have different morphologic characteristics compared to other non-mammalian vertebrate cells. These cells can participate in the aggregation process, as observed in birds.

Animals↗

The distribution of calcium buffering proteins in the turtle cochlea.

Hair cells of the inner ear contain high concentrations of calcium-binding proteins that limit calcium signals and prevent cross talk between different signaling pathways during auditory transduction. Using light microscope immunofluorescence and post-embedding immunogold labeling in the electron microscope, we characterized the distribution of three calcium-buffering proteins in the turtle cochlea. Both calbindin-D28k and parvalbumin-beta were confined to hair cells in which they showed a similar distribution, whereas calretinin was present mainly in hair-cell nuclei but also occurred in supporting cells and nerve fibers. The hair-cell concentration of calbindin-D28k but not of parvalbumin-beta increased from the low- to high-frequency end of the cochlea. Calibration against standards containing known amounts of calcium-buffering protein processed in the same fluid drop as the cochlear sections gave cytoplasmic concentrations of calbindin-D28k as 0.13-0.63 mm and parvalbumin-beta as approximately 0.25 mm, but calretinin was an order of magnitude less. Total amount of Ca 2+-binding sites on the proteins is at least 1.0 mm in low-frequency hair cells and 3.0 mm in high-frequency cells. Reverse transcription-PCR showed that mRNA for all three proteins was expressed in turtle hair cells. We suggest that calbindin-D28k and parvalbumin-beta may serve as endogenous mobile calcium buffers, but the predominantly nuclear location of calretinin argues for another role in calcium signaling. The results support conclusions from electrophysiological measurements that millimolar concentrations of endogenous calcium buffers are present in turtle hair cells. Parvalbumin-beta was also found in both inner and outer hair cells of the guinea pig cochlea.

Animals↗

Influence of nasal respiration upon normal EEG and epileptic electrographic activities in frog and turtle.

The electrographic respiratory response (ERR) was elicited by nasal air flow in the brain of the frog and turtle. It had the shape of a spindle of high voltage rhythmic activity and was propagated from the olfactory bulb predominantly into the ipsilateral hippocampal region in the frog and into the pyriform cortex in the turtle. In both animals, thalamic propagation of the ERR was also found. In both animals epileptic electrographic phenomena, were enhanced, created by local penicillin application. In the turtle epileptic electrographic manifestations were also elicited in the intact brain by simple nasal air insufflation. Diazepam (intraperitoneal administration) had no effect either on the ERR or on its triggering effect on epileptic phenomena. The possible physiological and pathophysiological interpretations of these findings are discussed.

Animals↗

Report of dysgerminoma in the ovaries of a snapping turtle (Chelydra serpentina) with discussion of ovarian neoplasms reported in reptilians and women.

A malnourished, captive, young adult (weight-11 kg, carapace length-25 cm), female snapping turtle (Chelydra serpentina) was presented for examination and treatment of malnutrition and multiple carapace necroses. Because treatment was unsuccessful, the animal was euthanatized and necropsied. The main necropsy observations showed the presence of a 9 cm greyish-white/yellow, soft, fleshy to fatlike mass involving the right ovary near the oviduct opening and multiple similar, pea-to-walnut sized masses involving both ovaries. Microscopic examination of formalin fixed, hematoxylin and eosin and silver stained tissue sections revealed the masses to be composed of primordial germ cells arranged in a pattern morphologically compatible with dysgerminoma as described in women and other mammals. Very rarely have ovarian neoplasms been reported in turtles or other reptiles. This is the first neoplasm described in the snapping turtle ovary and the first dysgerminoma reported in reptilians. A tabulation of previously documented ovarian neoplasia in reptiles and a comparison of this cancer to those occurring in women will be discussed.

Animals↗

Interrenal responses to high ambient temperature in soft-shelled turtle, Lissemys punctata punctata.

An exposure to ambient temperature of 25 degrees C had no perceptible effect on interrenal function but further increase of temperature to 35 degrees C caused nuclear hypertrophy with increase of nuclear diameter, RNA concentration, acid phosphatase and alkaline phosphatase activities, accompanied by quantitative depletions of cholesterol (free, esterified and total) and ascorbic acid levels in the interrenal gland of the soft-shelled turtle Lissemys p. punctata. Similar manifestations of stimulation, except in the nucleus, were marked after exposure to 38 degrees C, but the degree of response in respect of esterified and free cholesterol levels was higher at 38 degrees C than at 35 degrees C. Moreover, withdrawal of 38 degrees C temperature and subsequently maintaining at 25 degrees C for 15 days showed reverse manifestations to those of 35 degrees C/38 degrees C, leading to a tendency towards normalcy. It is suggested that high a ambient temperature of 35 degrees C significantly stimulates interrenal function of Lissemys turtles, but further increase of 38 degrees C does not cause further overall stimulation, and withdrawal of higher temperature (38 degrees C) shows a tendency towards normalcy. It is also suggested that (a) high ambient temperature causes thermal stress, (b) it is reversible and (c) it acts on interrenal activity presumably via CRF-ACTH-axis in turtles.

Acid Phosphatase↗

High density of neuropeptide Y-innervation in the myenteric plexus of the turtle midgut. An immunocytochemical study.

Using an indirect immunocytochemical method, a high density of NPY-containing neural network is revealed in the myenteric plexus of the midgut of the turtle, Pseudemys scripta elegans. The labelled elements included strongly stained small nerve cells and generally weakly labelled large ones of the plexus, as well as a substantial proportion of the nerve fibres within both the myenteric plexus and around blood vessels. Pericellular baskets around nonstained nerve cells and in some cases around weakly stained larger nerve cells were common. In the mammalian species the bulk of the NPY-immunoreactive nerve cells is found in the submucous plexus. In the turtle, however, NPY could be found in about 20-30% of the perikarya of the myenteric plexus. The layers of the circular and longitudinal musculature, on the other hand, seem to be hardly innervated by NPY-immunopositive fibres. Thus, NPY may fulfill a key role in the myenteric microcircuitry, but not in the direct regulation of smooth muscle movement, of the turtle small intestine.

Animals↗

Aerobic metabolism and swimming energetics of the painted turtle, Chrysemys picta.

Oxygen consumption rates (VO2) were measured for painted turtles (Chrysemys picta) swimming in a respirometer at controlled speeds. Sustained specific swimming speeds ranged from 0.75 to 1.52 body lengths (L) per s. Over most of this range endurance exceeded 30 min. VO2 increased curvillinearly with swimming speed (U) and the maximum active rate was 9 times resting (0.26 ml O2/min), and 3 times routine (0.64 ml O2/min). Mass specific metabolic scope was 228 ml O2/(kg.h), similar to that reported for other active chelonians. Cost of transport increased from 3.86 to 5.72 J/(kg.m) over the speed range tested. Swimming costs for rowing painted turtles are greater than those for marine reptiles utilizing anguilliform or lift-producing hydrofoil propulsion. The increased swimming cost for the amphibious painted turtle suggests that morphological specializations permitting effective terrestrial transport, increase energetic expenditures during swimming.

Animals↗

Alkali secretion in the turtle bladder: up-regulation by the phospho-inositol cascade and inhibition by diphenylamine carboxylate (DPC).

The presently reported studies of factors involved in the regulation of acid-base excretory processes in isolated turtle urinary bladders have yielded the following data. (i) There exists in alkalotic and euhydric turtle bladders (but not in acidotic turtle bladders) a mechanism which drives a primary active electrogenic secretion of alkali; and the electrogenic output of this mechanism is up-regulated by exogenously added PDE inhibitors, such as theophylline or IBMX. (ii) VIP or cAMP up-regulates this alkali secretion in the presence of IBMX. (iii) Carbachol also initiates alkali secretion. But this action, independent of PDE activity, is probably associated with the phospho-inositol reaction cascade. (iv) Finally, low concentrations of mucosal DPC decreases the carbachol supported, but not the cAMP-supported alkali secretion.

1-Methyl-3-isobutylxanthine↗

[Electron microscopic detection of herpesviruses in a mass death of Greek tortoises (Testudo hermanni) and four-toed turtles (Agrionemys horsfieldii)].

In a population of about 130 tortoises, consisting mainly of Hermann's tortoises (Testudo hermanni) and Four-toed tortoises (Agrionemys horsfieldii), 50% of the reptiles died within 3 months in autumn 1987. Post mortem analysis of 5 necropsied turtles revealed thick, caseous coatings in the upper digestive tract, hepatomegaly and enteritis. By microbiological examination a lot of ubiquitous bacteria could be isolated. By electron microscopy of concentrated and negatively stained gut specimens herpes virus particles were found in two Hermann's tortoises and one Four-toed tortoise. Isolation experiments in embryonic turtle tissue cultures showed no evidence of a cytopathogenic agent. The results are discussed in respect of their importance for the high mortality observed in the population of mediterranean land turtles.

Animals↗

A nonparametric comparison of monomolecular growth curves: application to western painted turtle data.

Intractable distributional assumptions are generated in parametric analyses comparing groups of subjects described by nonlinear growth models. The distributional situation becomes more complex when pointwise mean curves best describe group growth (instead of curves based on mean parameters). An interval specific randomization test is developed to handle monomolecular growth models. The need for the technique was motivated by a study describing longitudinal growth data from the annuli on abdominal scutes of groups of western painted turtles. The analyses indicate that female turtles grow larger than male through the first seven years of life. The analytical procedures developed for these turtles are useful in the description and analyses of many other growth processes.

Animals↗

Relationship of K and ammonia transport by the turtle bladder.

The relationship between K and ammonia transport was investigated in the turtle bladder. At serosal pH 6.4, ammonia transport is preferentially from serosa to mucosa and is, at least in part, mediated by NH4+ transport. Since K and NH4+ share similar features such as permeability and stimulation of Na-K-ATPase, we studied the interaction of transport of these ions by the turtle bladder. Removal of K from the mucosal solution inhibited partially ammonia transport from serosa to mucosa and the inhibition was reversible by restoration of K. In contrast, removal of serosal K failed to inhibit ammonia transport. Since NH4+ can replace K in the activation of Na-K-ATPase in turtle bladder plasma membrane fraction with similar K, we examined the effect of ouabain on ammonia transport. Ouabain added to the serosal solution failed to inhibit ammonia transport thus, suggesting that the Na-K-ATPase is not required for ammonia entry into the cell. Methylammonium (a competitive inhibitor of NH4+ transport in other systems) decreased both ammonia transport and the observed increase in short circuit current elicited by NH4Cl addition to the serosal solution. This finding suggests that NH4+ and methylammonium are transported through a common pathway in the serosal side. Since the permeability of the serosal side to K and NH4+ is similar, we evaluated the effect of serosal depolarization and the effect of barium, an inhibitor of K channels, on ammonia transport. Serosal depolarization inhibited ammonia transport but barium did not affect ammonia flux.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonia↗

Light and electron microscopy of S-antigen- and opsin-immunoreactive photoreceptors in the retina of turtle, chicken, and hedgehog.

S-antigen and opsin-immunoreactive sites were studied in the retina of turtle (Pseudemys scripta elegans), chicken (Gallus domesticus), and hedgehog, (Erinaceus roumanicus) by light-microscopic avidin-biotin-peroxidase and electron-microscopic protein A-gold and immunoglobulin-gold (immunogold) techniques. In general, S-antigen and opsin immunoreactions were exclusively localized to certain photoreceptors of the retinae studied. In turtle and chicken, strong S-antigen immunoreactivity was found in the outer and inner segments, perikarya and synaptic bases of rod photoreceptors. Some--apparently green--single cones also exhibited immunoreactive outer and inner segments. In hedgehog, the inner segments, perikarya and pedicles of rods displayed immunoreaction of varying intensities. In all three species there was an accumulation of immunogold particles on the distal portion of the inner segment, the connecting piece and the proximal portion of the outer segment. Opsin immunoreactivity was found in the outer segments of rod photoreceptors, and in those of--apparently green--single cones of turtle and chicken. The localization and significance of the S-antigen immunoreaction is discussed in connection with the occurrence of different photopigments in the retinae studied. The correlation of the presence of S-antigen and of either rhodopsin or porphyropsin in rod and--apparently green--single cone photoreceptors was emphasized.

Animals↗

Blends of rostral and caudal scratch reflex motor patterns elicited by simultaneous stimulation of two sites in the spinal turtle.

Simultaneous tactile stimulation of 2 sites on the body surface of a spinal turtle elicits complex blends of the scratch forms and motor patterns associated with each site. Our previous work has utilized 1-site stimulation to elicit distinct forms of the scratch reflex in the spinal turtle (Mortin et al., 1985; Robertson et al., 1985). Using this paradigm, stimulation of a site on the shell bridge anterior to the hindlimb elicits a rostral scratch reflex in which the dorsum of the foot rubs against the stimulated site; stimulation of a site near the tail elicits a caudal scratch reflex in which the heel or side of the foot rubs against the stimulated site (Mortin et al., 1985). During each scratch cycle, the monoarticular knee extensor muscle is active when the limb rubs against the stimulated site, and there is rhythmic alternation between hip protractor and hip retractor muscle activity (Robertson et al., 1985). In a rostral scratch, the monoarticular knee extensor muscle is active during the latter portion of hip protractor muscle activity; in a caudal scratch, the monoarticular knee extensor muscle is active near the end of hip retractor muscle activity. Pure-form motor patterns that are similar to those recorded from these muscles during movement can be recorded from the corresponding nerves in a spinal turtle immobilized with a neuromuscular blocking agent (Robertson et al., 1985). In this paper, we describe blend responses to simultaneous stimulation of 2 sites, one in the rostral scratch and the other in the caudal scratch receptive field. During these blends, the responding hindlimb rubs against both stimulated sites in one continuous movement sequence.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗