Embryogenesis and ossification of Emydura subglobosa (Testudines,Pleurodira, Chelidae) and patterns of turtle development

Using the Standard Event System (SES) to study patterns of vertebrate development, we describe a series of 17 embryos of the pleurodire turtle Emydura subglobosa. Based on a sequence heterochrony analysis including 23 tetrapod taxa, we identified autapomorphic developmental shifts that characterise Testudines, Cryptodira, and Pleurodira. The main results are that Testudines are characterised by an autapomorphic late neck development, whereas pleurodires and cryptodires show a different developmental timing of the mandibular process. Additionally, we described the ossification pattern of E. subglobosa and compared the data to those of five other turtles. Pleurodires show the epiplastron to ossify before or simultaneously with maxilla and dentary. In contrast, cryptodires show a later ossification of this bone. Because evolutionary developmental studies on turtles have previously focused only on “model organisms” that all belong to Cryptodira, we underline the necessity to include a pleurodire taxon for a more comprehensive, phylogenetically more informative approach. Developmental Dynamics 238:2770–2786, 2009. © 2009 Wiley‐Liss, Inc.     

Gastrointestinal parasites of owls (Strigiformes) kept in captivity in the Southern region of Brazil

The aim of this research was to study the gastrointestinal parasitism in 12 adult owls kept in captivity in the Southern region of Brazil. Cloacal contents of the species Rhinoptynx clamator, Tyto alba, Athene cunicularia, Megascops spp., and Bubo virginianus were evaluated. Feces and urine were collected and analyzed by the zinc sulfate centrifugal-flotation method and stained by the modified Ziehl–Neelsen technique. Eggs of Capillaria spp. and Strongylida, oocysts of Cryptosporidium spp., Eimeria spp., and Isospora spp. were observed. The birds showed no clinical signs, probably due to the mild nature of the infection.     

Determination of snake-necked turtle Hydromedusa tectifera (Cope, 1870) (Testudines: Chelidae) plasma protein concentrations by refractometry and the biuret method

The purpose of this study was to evaluate the accuracy of hand-held refractometer in determining plasma protein concentrations in South American snake-necked turtle (Hydromedusa tectifera) as compared with the standard biuret method. The results indicated that plasma protein values may be accurately determined in snake-necked turtle with a hand-held refractometer.     

Morphological Changes of the Epididymis and Description of the Excurrent Ducts of Phrynops geoffroanus (Testudines: Chelidae) During the Reproductive Cycle

The seminal ducts (efferent ductule, epididymis, and deferent duct) in adults of Phrynops geoffroanus were examined using light microscopy. A series of tubules (efferent ductules) connect the testes to the epididymides. The efferent ductules are formed by a rete of small tubules of varying diameters, with simple columnar epithelium formed by the ciliated cells, nonciliated cells, and few basal cells. The epididymis is a simple, long and highly convoluted tubule that receives the efferent ductules throughout its extension. It is covered by a pseudostratified columnar epithelium with three cellular types: the principal cells, which are the most abundant, basal cells, and a small narrow cell. The histological differences in the epididymis region (cranial, medial, and caudal), as well as the differences in the epithelium throughout the reproductive cycle, are discussed. The deferent ducts consist of a low pseudostratified epithelium with two cellular types: the principal and basal cells. During the months analyzed, spermatozoa were stored in the epididymis, and deferent ducts were found. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.     

An XX/XY sex microchromosome system in a freshwater turtle, Chelodina longicollis (Testudines: Chelidae) with genetic sex determination

Heteromorphic sex chromosomes are rare in turtles, having been described in only four species. Like many turtle species, the Australian freshwater turtle Chelodina longicollis has genetic sex determination, but no distinguishable (heteromorphic) sex chromosomes were identified in a previous karyotyping study. We used comparative genomic hybridization (CGH) to show that C. longicollis has an XX/XY system of chromosomal sex determination, involving a pair of microchromosomes. C-banding and reverse fluorescent staining also distinguished microchromosomes with different banding patterns in males and females in ∼70% cells examined. GTG-banding did not reveal any heteromorphic chromosomes, and no replication asynchrony on the X or Y microchromosomes was observed using replication banding. We conclude that there is a very small sequence difference between X and Y chromosomes in this species, a difference that is consistently detectable only by high-resolution molecular cytogenetic techniques, such as CGH. This is the first time a pair of microchromosomes has been identified as the sex chromosomes in a turtle species.     

Anti-dermatophyte activity of Leguminosae plants from Southern Brazil with emphasis on Mimosa pigra (Leguminosae)

1. Download : Download high-res image (133KB)
2. Download : Download full-size image

     

Tunga penetrans and further parasites in the giant anteater (Myrmecophaga tridactyla) from Minas Gerais, Brazil

The Brazilian savannah-like area, the Cerrado region, covers large areas of the country and provides a habitat for a multitude of different animal species. The giant anteater (Myrmecophaga tridactyla) is geographically widespread and one of the typical inhabitants of the Cerrado. They are listed as vulnerable by the International Union for Conservation of Nature and Natural Resources. A population loss of at least 30?% over the past 10?years has been estimated based on local extinctions, habitat loss and deaths caused by fires, roadkills and hunting. Little is known about ecological and in particular parasitic conditions of this highly specialised insectivore species. During September and November 2010 we examined three roadkilled giant anteater for the presence of metazoan ecto- and endoparasites. Besides the cestode species Oochoristica tetragonocephala and the tick species Amblyomma nodosum, we found for the first time the flea Tunga penetrans. Beside morphological flea species identification, we compared a fragment of the 16S rRNA gene of eggs, a molecular method utilised for the first time in this combination. The identification of T. penetrans in M. tridactyla represents a new host record and expands the host and distribution range of the zoonotic flea species.     

Nematode parasites of the digestive tract in Neotropic cormorant chicks (Phalacrocorax brasilianus) from the River Cruces Ramsar site in southern Chile

The neotropic cormorant (Phalacrocorax brasilianus) breeding colony of the Rio Cruces Nature Sanctuary and Ramsar site was surveyed for nematode parasites in southern Chile. Moribund chicks (n=128) of different ages were inspected for anchored nematodes using complete guts. We tested if chicks harbored the same parasites as the adults feeding them. Besides the known Contracaecum rudolphii, third or fourth stage larvae of Pseudoterranova sp. and Anisakis (type I and II) were obtained in this waterbird species for the first time. Most parasites were located in the stomach and C. rudolphii was the dominant species. The prevalence and mean intensity of C. rudolphii infections and the prevalence of Anisakis type I larvae were significantly less (P < 0.05) in the youngest age group of the birds. The prevalence of Pseudoterranova sp. larvae infection was similar among birds of different age. The mean intensity with Pseudoterranova sp. was significantly less (P < 0.05) in younger birds and in Anisakis type I it was similar in different age groups.     

Spatial-temporal variation of parasites in Cnemidophorus ocellifer (Teiidae) and Tropidurus hispidus and Tropidurus semitaeniatus (Tropiduridae) from Caatinga areas in northeastern Brazil

Parasites are natural regulators of their host populations. Despite this, little is known about variations in parasite composition (spatially or temporally) in environments subjected to water-related periodic stress such as the arid and semiarid regions. The objective of this study was to evaluate the spatial-temporal variation in endoparasite species’ abundance and richness in populations of Neotropical Cnemidophorus ocellifer, Tropidurus hispidus, and Tropidurus semitaeniatus lizards in the semiarid northeast of Brazil. The location influenced the abundance of parasites in all analyzed lizard species, while season (dry and rainy) only influenced the total abundance for T. hispidus. In all seasons, males significantly showed more endoparasites than females in all lizard species, although for T. hispidus, this difference was only found in the dry season. Seasonal variations affect the abundance patterns of parasites. Likely, variables include environmental variations such as humidity and temperature, which influence the development of endoparasite eggs when outside of the host. Further, the activity of the intermediate hosts and the parasites of heteroxenous life cycles could be affected by an environmental condition. The variation in the abundance of parasites between the sampling areas could be a reflection of variations in climate and physiochemical conditions. Also, it could be due to differences in the quality of the environment in which each host population lives.     

Phylogenetic analysis of small ruminant lentiviruses from Southern Brazil

The first lentivirus isolated from sheep in Brazil was analysed phylogenetically. Evolutionary trees of the proviral 597 nucleotide gag and 432 nucleotide pol sequences obtained by the maximum likelihood method demonstrated that the sheep isolate clustered with prototype Maedi Visna virus whereas three lentiviruses isolated from goats in the same geographic region were close to caprine arthritis encephalitis prototypes. A subsequent comparison of sequence data of these viruses with those contained in the EMBL sequence database revealed that, in contrast to caprine prototypic viruses, all prototypic Maedi Visna viruses contain a deletion of six nucleotides in the gag gene resulting in the deletion of two residues in the central region of capsid protein. This deletion may be a useful marker in the analysis of small ruminant lentiviruses, especially when considering possible transmission of lentiviruses between sheep and goats.     

Nematode parasites of rodents in Malaysia. II. Trichostrongyloidea

Many trichostrongyloid species parasitizing rodents in Malaysia were described in 1967 in a thesis that was never published. Some of these species have since been redescribed sometimes with, sometimes without reference to the thesis. The remaining species are redescribed using information given in the thesis and certain additional morphological data (in particular, the synlophe) taken from study of the paratypes. The species are reclassified according to criteria established in the most recent classification. The following genera are proposed: Brevistriatinae: - Macrostrongylus n. gen. characterized by a caudal bursa of Calypsostrongylus type and absence of synlophe. Nippostrongylinae: - Malaistrongylus n. gen. characterized by a synlophe of Heligmonoides type but with a larger number of ridges and by the fusion of rays 4 and 5 in the caudal bursa. - Rattus strongylus n. gen. characterized by small, subequal dorsal left ridges and a total number of ridges less than 20. - Sabanema n. gen. characterized by small subequal dorsal left ridges and a total number of ridges greater than 30. The species under consideration are the following: Hepatojarakus malayae Yeh, 1955; Pithecostrongylus bicapitatus n. sp. (= P. bicapitatus Ow Yang, 1967, in litt); Macrostrongylus ratti n. gen., n. sp. (= Macrostrongylus ratti Ow Yang, 1967, in litt.); Calypsostrongylus malayensis Durette-Desset, 1976 (= Brevistriata malayensis Ow Yang, 1967, in litt); Fissicauda callosciuri (Supperer et Kutzer, 1964); Fissicauda brevispicula n. sp. (= Brevistriata brevispicula Ow Yang, 1967, in litt.); Nippostrongylus brasiliensis (Travassos, 1914); Orientostrongylus tenorai Durette-Desset, 1970 (= Longistriata selangora Ow Yang, 1967, in litt.); O. krishnansamyi Durette-Desset et Lim-Boo-Liat, 1974 (= Longistriata malaccae Ow Yang, 1967, in litt.); Heligmonoides bulbosus n. sp. (= Heligmonina (Heligmonoides) bulbosa Ow Yang, 1967, in litt.); Heligmonoides lanceolatus n. sp. (= Heligmonina (Heligmonoides) lanceolata Ow Yang 1967, in litt.); Malaistrongylus odontospicularis n. gen., n. sp. (= Malaistrongylus odontospicularis Ow Yang, 1967, in litt.); Paraheligmonelloides triangulus n. sp. (= Longistriata triangulum Ow Yang, 1967, in litt.); P. annandalei n. sp. (= Longistriata annandalei Ow Yang, 1967, in litt.); P. rajah n. sp. (= Heligmonina (Heligmonoides) rajah Ow Yang, 1967, in litt.); Rattustrongylus odontoconus n. gen., n. sp. (= Longistriata odontocona Ow Yang, 1967, in litt.); R. rotundoconus n. sp. (= Longistriata rotundocona Ow Yang, 1967, in litt.); Sabanema sabana n. gen., n. sp. (= Longistriata sabana Ow Yang, 1967, in litt.); S. kepongi n. sp. (= Longistriata kepongi Ow Yang,     

Cytokine gene polymorphisms in populations from Parana,Southern Brazil

In this study, were genotyped 22 single nucleotide polymorphisms (SNPs) in 13 genes that encode the pro-inflammatory (IL-1α, IL-1β, IL-1R, IL-4Rα, IL-12, IFN-γ, TNF-α, and IL-2) and anti-inflammatory (IL-1RA, TGF-β, IL-4, IL-6 and IL-10) cytokines of 350 individuals by PCR-SSP (polymerase chain reaction – sequence specific primer). A total of 473 individuals were genotyped for IL17A and IL17F genes by PCR-RFLP (restriction fragment length polymorphism). The sample consisted of healthy and unrelated subjects from a mixed population from Parana state, in the South region of Brazil. The frequency analyses and genotype data are available in the Supplementary materials and are accessible at Allele Frequency Net Database (AFND).     

Haemogregarina podocnemis sp. nov.: description of a new species of Haemogregarina Danilewsky 1885 (Adeleina: Haemogregarinaidae) in free-living and captive yellow-spotted river turtles Podocnemis unifilis (Testudines: Podocnemididae) from Brazil

Parasitology Research - Based on morphological, morphometric, and molecular data, we describe a new hemoparasite of the genus Haemogregarina Danilewsky 1885, isolated from the Brazilian aquatic...     

Serological prevalence of Toxoplasma gondii antibodies in pregnant women from Southern Brazil

During 15 months (01 April 2003–31 July 2004), 20,389 women showing positive pregnancy tests were included in a serological evaluation of toxoplasmosis prevalence using automated immunoenzymatic assays. The women’s serum samples were tested for the presence of IgG and/or IgM antibodies. Overall, 53.03% of the women were positive for IgG and 3.26% were positive for IgM; the analysis used a chi-square adherence test and a significance level of 0.05 (χ ²?=?14,720.35; p?=?0.00). To discriminate between recent and past infection, IgG avidity tests (n?=?166) were carried out, of which 28.3% (n?=?47) presented low avidity. The seroconversion index observed in this study was 0.44%. The seroprevalence results obtained were similar to other serology data found in other regions of Brazil. These data demonstrate the importance of continuous regional and national seroepidemiological inquiries to define public health strategies that can revert and reduce serological prevalence, as described in other countries where toxoplasmosis monitoring is mandatory.     

Structure of parasites community in Chaetobranchopsis orbicularis (Cichlidae), a host from the Amazon River system in northern Brazil

The aim of this paper was to investigate the component communities of parasites in Chaetobranchopsis orbicularis from a tributary of the Amazon River system, in Northern Brazil. In 32 fish examined, 902,551 parasites were collected, including Ichthyophthirius multifiliis, Piscinoodinium pillulare, Sciadicleithrum geophagi, Posthodiplostomum sp., Clinostomum marginatum, Echinorhynchus paranensis, Neoechinorhynchus pterodoridis, and Dolops longicauda. I. multifiliis was the dominant and abundant parasite species. The ectoparasites presented aggregate dispersion, but the endoparasites showed random dispersion pattern. Mean species richness was 4.0 ± 1.5 parasites, mean Brillouin diversity (HB) was 0.33 ± 0.28, mean evenness was 0.15 ± 0.13, and Berger-Parker dominance (d) was 0.85 ± 0.17. The species richness of parasites and HB were positively correlated with the length of hosts. There was positive correlation between the abundance of P. pillulare and length and weight, between the abundance of I. multifiliis and weight, as well as between the abundance of E. paranensis and N. pterodoridis and the length of hosts. Body condition of the hosts was not affected by moderate parasitism. The low diversity of endoparasites indicates that C. orbicularis is a host with low position in the food web. This is the first record of all these parasites for C. orbicularis.