Die Verbreitung der Arizona-Bakterien unter den freilebenden Landschildkröten der Arten Testudo graeca und Testudo hermanni

Zusammenfassung Bei der Untersuchung von Kotproben 691 frei in der Natur lebender Landschildkröten der ArtenTestudo graeca undTestudo hermanni, die aus vielen Ortschaften Südost- und Südwest-Bulgariens stammen, wurde bei 73 Tieren (10,5%) das Vorhandensein vonArizona-Bakterien festgestellt. Die isolierten Kulturen gehörten sechs Serotypen an, und zwar wurden am häufigsten dieArizona -Typen 9a,b:26:21 und Arizona 18 (O-Form) angetroffen. Eine Mischkultur von zweiArizona-Serotypen wurde nur bei einer Schildkröte ermittelt. 46 der tierischenArizona-Dauerausscheider waren gleichzeitig auch Dauerausscheider von Salmonellen. Bei 39 von ihnen wurden noch je eineSalmonella-species und bei 7 je 2Salmonella-species entdeckt.Die Ergebnisse dieser Untersuchungen zeigen, daß dieArizona-Bakterien unter den freilebenden Landschildkröten dieser beiden Arten erheblich verbreitet sind.     

Ultrastructural study of the endocrine cells of the gut of Testudo graeca (Chelonia)

Summary The digestive tract of Testudo graeca (Chelonia) was investigated by means of electron microscopy using both conventional and immunocytochemical techniques. EC-, L-, D-, G-, B-, N- and EC-L-cells were detected. These cells share several common ultrastructural characteristics with the endocrine cells of mammals (i.e. clear cytoplasm, prominent Golgi apparatus, secretory granules etc.). EC and D₁ cells have so far not been described in the esophagus of any animal species; in the present study these cells have been observed in the esophagus of T. graeca. Of special interest was the presence of B-cells in the intestine, suggesting that the migration of B-cells from the gut to the pancreas to constitute pancreatic islets is not concluded in T. graeca. The present study demonstrates that the gut endocrine system of T. graeca is a complex structure containing a large variety of endocrine cell types similar in morphology to those found in higher vertebrates.     

Leptoconops bezzii (Diptera: Ceratopogonidae) parasitizing tortoises Testudo graeca (Testudines: Testudinidae) in mountain ranges of Lebanon and western Syria

Biting midges of the genus Leptoconops, subgenus Leptoconops (Diptera: Ceratopogonidae) were repeatedly found parasitizing on spur-thighed tortoises Testudo graeca in western Syria and Lebanon. Collected females were assigned to the species L. bezzii according to their morphological characteristics. Tortoises parasitized by midges were observed throughout the daytime, under mild temperatures, and slight winds, in Mediterranean or stony steppe habitats. Intensity of the infestations ranged from a few specimens up to thousands of midges per tortoise. Midges infested predominantly the tortoises’ carapax, finding their approach to the capillaries in the seams between the keratinized scutes. The vector potential of ceratopogonids is discussed.     

Enzyme-linked immunosorbent assay for detecting herpesvirus exposure in Mediterranean tortoises (spur-thighed tortoise [Testudo graeca] and Hermann's tortoise [Testudo hermanni])

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies to a herpesvirus associated with an upper respiratory tract disease in Mediterranean tortoises [spur-thighed tortoise (Testudo graeca) and Hermann's tortoise (Testudo hermanni)]. This serodiagnostic test was validated through a hyperimmunization study. The mean of the A(405) readings of the plasma samples collected at time zero of the hyperimmunization study plus three times the standard deviation was used as the cutoff for seropositivity in tortoises. ELISA results were compared to serum neutralization (SN) values for the same samples by using the McNemar test. The results obtained by SN and ELISA were not significantly different (P > 0.05). This new ELISA could be used as an important diagnostic tool for screening wild populations and private and zoo collections of Mediterranean tortoises.     

Haplodiploidy in Pharyngodonid (Oxyuroidea: Nematoda) parasites of Testudo graeca

Gametogenesis is described in Tachygonetria conica, T. dentata, T. macrolaimus, T. numidica, T. longicollis longicollis, T. l. pusilla, T. l. setosa, Mehdiella uncinata and M. microstoma, parasites of Testudo graeca from Tunisia. All species reproduced by haplodiploidy (males developed from unfertilized eggs and were haploid and females developed from fertilized eggs and were diploid). Metaphase of oogonial divisions contained ten rod-shaped chromosomes and meiosis in females resulted in two polar bodies and an egg pronucleus. Embryos in eggs in utero contained either five or ten chromosomes depending presumably on whether or not they developed from fertilized ova. Metaphase of spermatogonial divisions contained five rod-shaped chromosomes but divisions just anterior to the seminal vesicle contained five short round chromosomes similar to meiotic chromosomes but consisting of only two chromatids. Males of haplodiploid species have no homologous chromosomes and it is suggested that meiosis during spermatogenesis, rather than being replaced by mitosis as previously suggested (Adamson, 1981), simply begins at the second meiotic division.     

Prevalence and intensity of blood apicomplexan infections in reptiles from Romania

In order to evaluate prevalence and intensity of apicomplexan hemoparasites in free-ranging reptiles from Romania, blood smears were collected from European pond turtles (Emys orbicularis), sand lizards (Lacerta agilis), and spur-thighed tortoises (Testudo graeca). All three host species were positive for blood parasites, with prevalence of infected individuals between 60.71% and 100% and variable intensity. Similarities and differences with other epidemiological data are discussed.     

Isolation and characterization of an iridovirus from Hermann’s tortoises (Testudo hermanni)

Summary.  A virus was isolated from tissues of 2 diseased Hermann’s tortoises (Testudo hermanni) and preliminarily characterized as an iridovirus. This conclusion was based on the presence of inclusion bodies in the cytoplasm of infected cells, sensitivity to chloroform, inhibition of virus replication by 5-iodo-2′-desoxyuridine and the size and icosahedral morphology of viral particles. The virus was able to replicate in several reptilian, avian and mammalian cell lines at 28°C, but not at 37°C. Restriction enzyme analysis showed resistance of the ral DNA to digestion with HpaII due to methylation of the internal cytosine at CCGG sequences. Part of the genomic region encoding the major capsid protein was amplified by PCR and subjected to sequence analysis. Comparative analysis of the obtained nucleotide sequence revealed that the isolate is closely related to frog virus 3, the type species of the genus Ranavirus. Accepted May 14, 1999 Received January 27, 1999     

Efficacy of oxfendazole and fenbendazole against tortoise (Testudo hermanni) oxyurids

Thirty-six tortoises (Testudo hermanni) with naturally acquired oxyurids infections were used to assess the anthelmintic efficacy of oxfendazole (Dolthene; Merial) and fenbendazole (Panacur; Hoechst Roussel Vet). Animals were randomly assigned to three groups (A, B, and C) based on sex and weight. Animals in group A (seven males and six females) were orally treated with oxfendazole at dose rate of 66 mg/kg, group B animals (nine males and eight females) were orally treated with fenbendazole at dose rate of 100 mg/kg, and group C animals (three males and three females) were not treated and served as controls. All animals were individually stabled in plexiglas boxes under controlled conditions of temperature, humidity, and light beginning 7 days pretreatment and continuing for the duration of the trial. Individual tortoises feces were examined daily by the McMaster technique and drugs efficacy was assessed by the fecal eggs count reduction (FECR) test. Both drugs showed 100% of FECR. However, oxfendazole reached this level 12 days after treatment, whereas 31 days after treatment were necessary to obtain the same stable result with fenbendazole. The two drugs were well tolerated by all the animals and no adverse reactions were observed after treatment.     

Ein Beitrag zur Kenntnis parasitischer Nematoden aus griechischen Landschildkröten

Zusammenfassung 1. Griechische Landschildkröten wurden auf parasitische Nematoden ihrer Verdauungsorgane untersucht.2. Neben den bereits bekannten Arten Tachygonetria longicollis, Oxyuris robusta, O. dentata, Mehdiella microstoma, M. inflata, Atractis dactylura, Angusticaecum holoptera wurden folgende neue Arten entdeckt und beschrieben: Tachygonetria testudinis n. sp., die Männchen von Mehdiella inflata, Männchen von M. hamosa n. sp., Männchen von M. cordata n. sp., Weibchen von Oxyuris lata n. sp., Weibchen von Macracis papillosa n. sp. sowie Männchen und Weibchen von Alaeuris forcipiformis n. sp.3. Als alleiniger Parasit wurde Alaeuris forcipiformis n. sp. im Magen und Angusticaecum holoptera im Dünndarm gefunden. Sonst lagen stets Mischinvasionen vieler Arten und derer larvalen Stadien vor.4. Die Anzahl der an den Mischinvasionen beteiligten Parasiten war stets sehr hoch. In einem Fall betrug sie über 5000 Exemplare.5. Sämtliche Arten der gefundenen Oxyuriden wurden einander photographisch in Gesamtaufnahmen gegenübergestellt und durch Zeichnungen der männlichen Genitalanhänge bei starker Vergrößerung ergänzt.6. Die wichtigsten Durchschnittsmaße wurden in Tabellen zusammengestellt.Mit 27 Textabbildungen     

A neurilemmal sarcoma in a tortoise (Testudo hermanni)

A proliferative lesion in a Hermann's tortoise (Testudo hermanni) was identified as a neurilemmal sarcoma: it was successfully treated by excision and cryosurgery.     

A new species of <Emphasis Type="Italic">Falcaustra</Emphasis> (Nematoda,Kathlaniidae) and other nematodes from <Emphasis Type="Italic">Sphenomorphus simus</Emphasis> (Squamata,Scincidae) from Papua New Guinea

Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules (561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species.     

Activity of vagal afferent fibers innervating CO2-sensitive receptors in the tortoise, Testudo hermanni

Experiments were done on the tortoise, Testudo hermanni (anesthetized), or on its lung-vagus preparation in which all other internal organs had been removed. By recording the afferent impulse patterns in fine strands of the vagus, three kinds of CO2-sensitive receptors were demonstrated. Heymans-type chemoreceptors: Afferents originating from thoracic arterial chemoreceptors fired randomly at amplitudes below 100 microV. Firing frequency increased when the animal was ventilated with CO2-enriched, nitrogen or hypoxic mixtures, or was given NaCN. Intrapulmonary CO2 receptors (IPC). In an artificially ventilated tortoise and in lung-vagus preparations where the lung CO2-fraction (FCO2) was below 2.5%, single units with a spike amplitude above 200 microV fired regularly. When CO2-enriched air was inspired, impulse frequency decreased markedly, and when the lung was washed with air, it returned to the control frequency following the initial excitation. In lung-vagus preparations the impulse frequency did not change with lung inflation, was null for FCO2 greater than 2.5-3.5%, and was inversely proportional to lower FCO2's. Intrapulmonary CO2-sensitive mechanoreceptors: In anesthetized artificially ventilated tortoises, impulse bursts synchronized with inspiration decreased when the animal inspired 5 or 10% CO2 in air. In lung-vagus preparations, slowly adapting mechanoreceptor responses provoked by lung inflation were reduced when the lung was inflated with CO2-enriched air.     

Phylogenetic relationships of Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) within the order Spirurida inferred using mitochondrial cytochrome c oxidase subunit 1 (cox1) gene analysis

The present study investigated genetic variability within a population of Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) affecting horses in an endemic area of central Italy using polymerase chain reaction (PCR)-coupled sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). No different cox1 sequences were detected in any of the H. muscae individual, while two haplotypes representing H. microstoma individuals differed for one substitution. The pairwise distance between the H. muscae and H. microstoma was 11%, coding for five amino acid changes. The sequence of an informative region within the cox1 gene of H. microstoma and H. muscae was analyzed by Maximum Likelihood and Bayesian phylogenetic methods using available mitochondrial sequences spirurid taxa belonging to Filarioidea, Thelazioidea, and Habronematoidea. Phylogenetic analysis supported the split of the tree into two sister spirurid groups, Habronematoidea and Filarioidea + Thelazioidea. The phylogenetic and evolutionary implications of Habronema with Filaroidea and Thelazioidea are discussed.     

Morphological differentiation among three <Emphasis Type="Italic">Thelazia</Emphasis> species (Nematoda: Thelaziidae) by scanning electron microscopy

Thelaziasis is an ocular infection of several mammals caused by nematodes of the genus Thelazia (Spirurida, Thelaziidae). The adults live in the lachrymal ducts and conjunctival sacs of infected animals, and transmission occurs by means of different species of muscids. T. rhodesi, T. skrjabini, and T. gulosa affect mainly cattle, inducing conjunctivitis, keratitis, and ocular discharge. This article describes the morphological features of adult T. rhodesi, T. skrjabini, and T. gulosa by scanning electron microscopy and highlights the most relevant differences for their identification.     

A new species of <Emphasis Type="Italic">Falcaustra</Emphasis> (Nematoda,Kathlaniidae) from <Emphasis Type="Italic">Cnemaspis</Emphasis> aff. <Emphasis Type="Italic">tro pidogaster</Emphasis> (Squamata,Gekkonidae) from Sri Lanka

Falcaustra desilvai sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Cnemaspis aff. tropidogaster (Squamata, Gekkonidae) is described and illustrated. Falcaustra desilvai represents the 4th nematode species from Sri Lanka to be assigned to the genus and is distinguished from other Sri Lankan species by the distribution pattern of caudal papillae (12 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (956–1046 μm) and absence of a pseudosucker.     

Differentiation of chromaffin cells in the developing adrenal gland of Testudo hermanni

The aim of this study was to investigate the development and differentiation of chromaffin cells in the adrenal gland of the turtle Testudo hermanni during ontogenesis using histological, immunocytochemical and ultrastructural methods. The 26 developmental stages were divided into three periods: in the early period (stages 1-18, up to 20 days of incubation at 37 degrees Celsius and 85% humidity), the chromaffin cells were observed from stage 12. They followed a ventro-lateral migration pathway with respect to the notochord and dorsal aorta, forming groups embedded in undifferentiated mesenchymal tissue. They reached the kidney surface only at the end of this period. Under the EM the chromaffin cells showed typical embryonic characters, such as rounded shape, high nucleus/plasmatic ratio, cell membrane with elongated processes; the cytoplasm contained a large number of free ribosomes, Golgi complexes, RER and a few chromaffin granules distributed in small sets. The granules were small and displayed a high electrondensity. Numerous unmyelinated fibres ran close to the chromaffin cells. At the end of this period both nervous elements and chromaffin cells were positive to the antigen for DbetaH. The intermediate period (stages 19-22, incubation days 21-35) was characterized by the first occurrence of steroidogenic cells on the ventro-medial kidney surface. Some chromaffin cells were still found in the same position, whereas other cells were still migrating, maintaining their embryonic character. It was possible to divide the secretory granules into two types according to their shape and electrondensity: the more numerous N-type granules had a dark content, whereas the small number of A-type granules (consistent with the scarce PNMT reaction) displayed a light content. They occurred for the first time in this period. In the advanced period (stages 23-26, from incubation day 36 to hatching) the adrenal gland reached its definitive shape, although remaining immature; groups of variously sized chromaffin cells intermingled with steroidogenic cells, both lying on the kidney surface. Chromaffin granules were more numerous and larger than in the previous stages, frequently mingling in the same cell. A migration pathway of the chromaffin cells along the nerve fibres can be hypothesized on the basis of their common origin and closeness. The polymorphic shape of chromaffin cells with long cytoplasmic processes also accounts for their migrating fitness. We can assume that steroidogenic differentiation from the mesodermic blastema begins after the first chromaffin cells have completed their migration.     

Osmoregulation of Hymenolepis microstoma

Summary The present report deals with a study of the osmoregulation of young Hymenolepis microstoma using the in vitro cultivation at different osmotic pressures: i.e. in eleven media with freezing point depressions ranging from 0.35 to 1.21° C. It has been shown that H. microstoma is able to develop optimally and equally well in media with freezing point depressions from 0.50 to 0.73° C. The worm seems to have a regulatory system operating successfully between these approximate limits. Media with lower or higher osmotic pressures do not cause death within the present experimental conditions but inhibit development gradually.It is concluded that, although cestodes are regarded as poikilosmotic, the present results with H. microstoma indicate that homoiosmotic properties might exist within a certain limited range of osmotic pressures.Supported by a N.A.T.O. grant.Encouragement by Prof. Dr. C. A. Hopkins is gratefully acknowledged.     

A new species of Cosmocerca (Nematoda, Cosmocercidae) and other helminths from Genyophryne thomsoni (Anura, Microhylidae) from Papua New Guinea

Cosmocerca tyleri sp. nov. (Ascaridida, Cosmocercidae) from the large intestine of Genyophryne thomsoni (Anura, Microhylidae) is described and illustrated. Cosmocerca tyleri sp. nov. represents the 23rd species assigned to the genus and the 6th from the Australian realm. Of the 5 Australian species previously described, C. tyleri sp. nov. differs from C. limnodynastes and C. novaeguineae in number of plectanes, 4 pairs in C. tyleri, 5 pairs in C. limnodynastes and C. novaeguineae. Cosmocerca australis has 3–4 pairs of plectanes, C. archeyi and C. zugi each have 4 pairs of plectanes; however, in each species the plectanes lie in the fourth quarter of the body and just anterior to the cloaca. In C. tyleri sp. nov. the plectanes lie in the third quarter of the body and there is significant space between the cloaca and the posterior pair of plectanes.