Unoculubranchiobdella sp. (Hirudinea: Ozobranchidae) as a vector for Haemogregarina spp. in freshwater turtles from Brazil.

Species of Haemogregarina are blood parasites known to parasitise vertebrate hosts, including fishes (Haemogregarina sensu lato) and freshwater turtles (Haemogregarina sensu stricto). Their vectors, include gnathiid isopods and leeches, respectively. In turtles, Haemogregarina balli has the best-characterized life cycle in the genus. However, no studies in Brazil have suggested a possible vector for any species of Haemogregarina from freshwater turtles. Therefore, in the present study, we provide insights into a leech vector based on specimens found feeding on two species of freshwater turtles, Podocnemis unifilis and Podocnemis expansa, using morphological and molecular data. In 2017 and 2019, freshwater turtles were collected in Goiás State, Brazil. Hosts were inspected for ectoparasites and leeches were collected from two specimens of P. expansa and nine specimens of P. unifilis. Leeches were subsequently identified as members of the genus Unoculubranchiobdella. Leech histological slides revealed haemogregarine-like structures, similar to post-sporogonic merogony, found near the gills and within the posterior sucker. Molecular analysis of the haemeogregarines resulted in the identification of three species of Haemogregarina: Haemogregarina embaubali, Haemogregarina goianensis, and Haemogregarina brasiliana. Therefore, our findings, based on morphology and DNA data suggest leeches of the genus Unoculubranchiondella as vectors for at least three species of Haemogregarina from Brazilian turtles.

Pharmacokinetics and pharmacodynamics of dextroketamine alone or combined with midazolam in Caiman crocodilus.

Pharmacokinetics studies of anesthetic agents are important for understanding of the pharmacology and metabolism of anesthetic agents in reptilians. This study was designed to examine the pharmacokinetic and pharmacodynamic properties of intravenous dextroketamine alone or combined with midazolam in Caiman crocodilus. Eight caimans were anesthetized with dextroketamine (10 mg/kg; group D) or dextroketamine and midazolam (10 and 0.5 mg/kg respectively; group DM) into the occipital venous sinus. The pharmacokinetic parameters were calculated by HPLC using a non-compartmental modeling. Serial blood samples were collected at baseline and within 15 and 30 min, and 11.5, 2, 4, 8, 12, 24 and 48 h of drug administration. Sedation status over time differed between groups. All animals in group D (8/8; 100%) showed signs of light sedation at t10. Half (4/8; 50%) of these caimans did not progress to deeper levels of sedation. In spite of light sedation at t10, animals in group DM were deeply sedated within 13.13 ± 7.04 min of anesthetic agent injection. The area under the plasma concentration-time curve (AUC0-48) and half-life of dextroketamine changed significantly after combination with midazolam. Even without significant changes in clearance, the almost two-fold increase in the half-life of dextroketamine suggests a slower rate of elimination.

A new myxozoan species Henneguya unitaeniata sp. nov. (Cnidaria: Myxosporea) on gills of Hoplerythrinus unitaeniatus from Mato Grosso State, Brazil.

On the basis of morphological and molecular analyses, a new myxozoan parasite is described from the gills of the fish Hoplerythrinus unitaeniatus, collected in the municipality of Nova Xavantina, Mato Grosso State, Brazil. Plasmodia of Henneguya unitaeniata sp. nov. were oval and whitish and were found surrounded by collagen fibers forming plasmodia wall between gill filaments on the gill arch. The spores were ellipsoidal with two similar polar capsules. Morphometric analysis showed a total spore mean length of 23.8 ± 1.5 µm, spore body mean length of 14.5 ± 0.7 µm, caudal appendage mean length of 10.3 ± 1.4 µm, thickness mean length of 4.3 ± 0.3 µm, polar capsule mean length of 4.2 ± 0.5 µm, polar capsule mean width of 1.8 ± 0.3 µm, spore mean width of 4.8 ± 0.4 µm, and 4-5 polar filament coils. Phylogenetic analysis showed Henneguya unitaeniata sp. nov. as a basal species in a subclade formed by myxozoans that parasitize bryconid fishes.

Effects of egg exposure to atrazine and/or glyphosate on bone development in Podocnemis unifilis (Testudines, Podocnemididae).

This study was designed to investigate skeletal changes in Podocnemis unifilis embryos derived from artificially incubated eggs exposed to different concentrations of atrazine, glyphosate or atrazine and glyphosate mixture. Forty-two eggs were randomly allocated to one of seven trays containing vermiculite treated distilled water (control group) or the following solutions: 2 or 200 µg L-1 of atrazine (groups A1 and A2 respectively); 65 or 6500 µg L-1 of glyphosate (groups G1 and G2 respectively); 2 µg L-1 and 65 µg L-1 or 200 µg L-1 and 6500 µg L-1 of atrazine and glyphosate mixture (groups AG1 and AG2 respectively). Three eggs per tray were randomly collected on days 30 and 50 of the incubation period. Embryos were submitted to soft tissue diaphanization and stained with Alizarin red S or Alcian blue for morphological analysis of bone and cartilage tissues; histological analysis was performed to confirm ossification changes. Findings were compared between groups. Morphological changes were limited to sclerotic ring features and number of ribs. Malformations rates differed significantly (p < 0.05) between embryos in the control and treated groups A2, AG1 and AG2. Concurrent exposure to atrazine and glyphosate did not affect the presence or severity of embryonic malformations and was not associated with appendicular skeleton changes in P. unifilis embryos. However, further studies focusing on the axial skeleton with particular emphasis on rib abnormalities are warranted.

Functional myology of the thoracic limb in Pampas fox (Lycalopex gymnocercus): a descriptive and comparative analysis.

The characteristics of the muscles of the thoracic limb were evaluated in 22 specimens of Lycalopex gymnocercus. Descriptive and comparative analyses showed similarity with other canids in terms of topography and tendon insertions. Differences with the domestic dog were observed in the pectoralis profundus, triceps brachii and interflexorii muscles. Intraspecific variations were observed in the rhomboideus capitis, serratus ventralis cervicis, extensor carpi radialis, extensor digiti I and II, lumbricales, flexor digiti I brevis, abductor digiti I brevis, and flexor digiti V muscles. The analyses of muscle architecture carried out in nine specimens showed that there was no difference in muscle percentage mass in the thoracic limb of males and females, but a young specimen showed significant lower percentage mass. The triceps brachii caput longus muscle showed the greatest mass, the subscapularis muscle showed the greatest physiological cross-sectional area value, and the extrinsic muscles, in general, presented the longest fascicles and higher architectural indexes. Muscle architecture data were compatible with those of a thoracic limb adapted to fast cursorial locomotion that prioritizes movements in a sagittal plane instead of rotation or adduction/abduction. There was a high association between functional percentage mass of the muscles in the thoracic limb and phylogeny in the Carnivora order. It may be inferred that carnivoran muscle mass is largely determined by phylogeny.

Molecular characterization and identification of Hepatozoon species Miller, 1908 (Apicomplexa: Adeleina: Hepatozoidae) in captive snakes from Brazil.

Species of Hepatozoon are parasites frequently recorded in snakes. The species identification of this genus was based mostly on the gametocyte morphology and morphometric calculations. For more reliable results, molecular characterization, an initial step for the correct identification of Hepatozoon species, has been used. This study aimed to determine the prevalence and identification of Hepatozoon species in captive snakes from Brazil. To that end, morphological, morphometric, and molecular data were obtained. A total of 157 snakes; 128 venomous (Crotalus durissus) and 29 non-venomous (Epicrates crassus and Boa constrictor) were screened for Hepatozoon blood parasites. Using light microscopy, 20 (12.78%) snakes were found positive for Hepatozoon spp., of which 6/29 (20.7%) were non-venomous and 14/128 (10.9%) were venomous; all with low parasitemia. Polymerase chain reaction (PCR), performed with the primers HepF300/Hep900, confirmed all 20 (100%) samples positive for hemogregarines. Species of Hepatozoon were identified from eight sequenced samples. Two previously described species, Hepatozoon cuestensis and Hepatozoon musa, were identified. The present study is the first to report H. musa within the snake hosts E. crassus and C. durrisus. In addition, a potentially new Hepatozoon species from B. constrictor was identified.

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.

Based on morphological, morphometric, and molecular data, we describe a new hemoparasite of the genus Haemogregarina Danilewsky 1885, isolated from the Brazilian aquatic turtle Podocnemis unifilis (Testudines: Podocnemididae). The new species, Haemogregarina podocnemis sp. nov. (Apicomplexa: Haemogregarinidae), is characterized by small trophozoites with a single cytoplasmic vacuole on one side; pre-meronts with nuclear chromatin dispersed in the cytoplasm, with or without cytoplasmic vacuoles; meronts that are usually broad and slightly curved (kidney-shaped), with an average of eight small rectangular nuclei; immature gamonts (bean-shaped) with two morphological types: one with nuclear chromatin dispersed in the cytoplasm and the other with nuclei in the middle of the cell; mature gamonts of two morphological types: one with a length equal to or greater than that of the erythrocyte and the width of the nuclei similar to that of the hemoparasite and the other smaller than the erythrocyte with the width of the nuclei less than that of the hemoparasite. This is the first hemogregarine species described that infects the Brazilian turtle Po. unifilis. These findings highlight the need for further studies of Haemogregarina spp. to better determine the biodiversity of this understudied parasite group.

Effects of the exposure to atrazine on bone development of Podocnemis expansa (Testudines, Podocnemididae).

The use of pesticides is a widely spread practice in Brazilian agriculture, and dispersion of these substances is an important factor for the fauna and flora. Atrazine is an endocrine disruptor in the xenoestrogen class that is used worldwide in agricultural practices. In Brazil, its use is permitted in several crops. Podocnemis expansa is a representative of the Testudines order that is the largest freshwater reptile of South America. Its distribution enables it to get in contact with molecules that are commonly used as pesticides, which may cause deleterious effects in target populations. In order to evaluate the possible effects of the exposure to atrazine on bone ontogeny of this species, eggs were artificially incubated in sand moistened with water contaminated with atrazine at concentrations equal to 0, 2, 20 or 200 µg/L. Embryos were collected throughout incubation and submitted to diaphanization of soft tissues with potassium hydroxide (KOH); bones were stained with Alizarin red S and cartilages by Alcian blue. Embryos were evaluated for the presence of abnormalities during the different stages of pre-natal development of skeletal elements. No effect of atrazine was observed on bone development during the embryonic phase in P. expansa individuals, in the conditions of this study.

MANDIBULAR MORPHOMETRY APPLIED TO ANESTHETIC BLOCKAGE IN THE MANED WOLF (CHRYSOCYON BRACHYURUS).

Chrysocyon brachyurus (maned wolf) is the biggest South American canid and has a high frequency of dental injuries, both in the wild and in captivity. Thus, veterinary procedures are necessary to preserve the feeding capacity of hundreds of captive specimens worldwide. The aim of this study was to investigate the mandibular morphometry of the maned wolf with emphasis on the establishment of anatomic references for anesthetic block of the inferior alveolar and mental nerves. Therefore, 16 measurements in 22 mandibles of C. brachyurus adults were taken. For extraoral block of the inferior alveolar nerve at the level of the mandibular foramen, the needle should be advanced close to the medial face of the mandibular ramus for 11.4 mm perpendicular to the palpable concavity. In another extraoral approach, the needle may be introduced for 30.4 mm from the angular process at a 20-25° angle to the ventral margin. For blocking only the mental nerve, the needle should be inserted for 10 mm from ventral border, close to the labial surface of the mandibular body, at the level of the lower first premolar. The mandibular foramen showed similar position, size, and symmetry in the maned wolf specimens examined. Comparison of the data observed here with those available for other carnivores indicates the need to determine these anatomic references specifically for each species.

Effects of Exposure to Methyl Parathion on Egg Hatchability and Eggshell Chemical Composition in Podocnemis expansa (Testudines, Podocnemididae).

Eggshell evaluation may serve as an indicator of the effect of substances released in the environment, which may change eggshell shape, size, structure, and/or chemical composition. Additionally, exposure may interfere with hatching rates in contaminated eggs. The objective of this study was to better understand how exposure to the insecticide methyl parathion interferes with chemical changes in eggshells of Podocnemis expansa throughout their artificial incubation, as well as with egg hatchability. A total of 343 P. expansa eggs were collected in a natural reproduction area for the species. These eggs were transferred to and artificially incubated in the Wild Animal Teaching and Research Laboratory at Universidade Federal de Uberlândia. On the first day of artificial incubation, 0, 35, 350, and 3500 ppb of methyl parathion were incorporated to the substrate. Eggs were collected every three days for chemical analysis of eggshells. Hatchability was evaluated as the number of hatchlings in each treatment, for the eggs that were not used in the chemical analysis. Student's T-test was used for data on eggshell chemical composition, and the Binomial Test for Two Proportions was used in the hatchability analysis, at a 5% significance level. It was observed that the incorporation of methyl parathion to the substrate on the first day of artificial incubation of P. expansa eggs reduced the levels of total fat in the shells throughout their incubation, besides reducing egg hatchability.

Clostridium difficile and Clostridium perfringens from wild carnivore species in Brazil.

Despite some case reports, the importance of Clostridium perfringens and Clostridium difficile for wild carnivores remains unclear. Thus, the objective of this study was to identify C. perfringens and C. difficile strains in stool samples from wild carnivore species in Brazil. A total of 34 stool samples were collected and subjected to C. perfringens and C. difficile isolation. Suggestive colonies of C. perfringens were then analyzed for genes encoding the major C. perfringens toxins (alpha, beta, epsilon and iota) and the beta-2 toxin (cpb2), enterotoxin (cpe) and NetB (netb) genes. C. difficile strains were analyzed by multiplex-PCR for toxins A (tcdA) and B (tcdB) and a binary toxin gene (cdtB) and also submitted to a PCR ribotyping. Unthawed aliquots of samples positive for C. difficile isolation were subjected to the detection of A/B toxins by a cytotoxicity assay (CTA). C. perfringens was isolated from 26 samples (76.5%), all of which were genotyped as type A. The netb gene was not detected, whereas the cpb2 and cpe genes were found in nine and three C. perfringens strains, respectively. C. difficile was isolated from two (5.9%) samples. A non-toxigenic strain was recovered from a non-diarrheic maned wolf (Chrysocyon brachyurus). Conversely, a toxigenic strain was found in the sample of a diarrheic ocelot (Leopardus pardallis); an unthawed stool sample was also positive for A/B toxins by CTA, indicating a diagnosis of C. difficile-associated diarrhea in this animal. The present work suggests that wild carnivore species could carry C. difficile strains and that they could be susceptible to C. difficile infection.

Coronary anatomy in neotropical carnivores: A comparative analysis.

This study aims to investigate the anatomy of coronary arteries and their primary branches in neotropical carnivores, given the functional significance of coronary circulation and the limited existing descriptions in this order. For this purpose, coronary arteries were dissected, and their branches were counted in 74 hearts from 20 species belonging to five families: Canidae, Mustelidae, Procyonidae, Mephitidae, and Felidae. In all specimens of the suborder Caniformia, the subsinuosal interventricular branch originated at the end of the circumflex branch of the left coronary artery (LCA). In contrast, in all hearts of Felidae specimens, the subsinuosal branch was derived from the right coronary artery. Among the 50 neotropical specimens of the suborder Caniformia, 13.1 ± 5.2 ventricular branches originated from the LCA and only 4.6 ± 1.4 from the right (p < 0.0001), characterizing a consistent left dominance. However, in the 24 specimens of the Felidae family, 10.5 ± 4.0 ventricular branches were found originating from the LCA and 10.4 ± 3.4 from the right, with no difference between the means (p = 0.82), defining a balanced pattern. It is suggested that the type of coronary circulation may correlate with the phylogeny of carnivorans.

Integrative taxonomy in the genus Rhabdias Stiles et Hassall, 1905 from anuran in Brazil, description of two new species and phylogenetic analyses.

About 20 valid species of the genus Rhabdias are known in the Neotropical region. The present study aimed to describe two new species of Rhabdias parasitizing the lungs of Leptodactylus macrosternum and Leptodactylus podicipinus from Brazil. Distinctive characteristics between these species are numerous and based on body size, size of the buccal capsule, shape and size of the oesophagus, and position of the vulva. Molecular data based on ribosomal genes 28S and ITS region and mitochondrial COI of the two species are presented. Molecular analysis and comparison of the partial mitochondrial COI sequence of Rhabdias matogrossensis n. sp. and Rhabdias guaianensis n. sp. revealed a genetic divergence between these new species and the sequences of Rhabdias spp. previously deposited in GenBank. In the phylogenetic analysis, R. matogrossensis n. sp. was grouped with R. breviensis species complex, and R. guaianensis n. sp. was grouped as a sister group of R. cf. stenochepala. This study contributes to improving the diversity of known species of Rhabdias described in Brazilian anurans.

Eggshell composition of Amazon turtle (Podocnemis expansa) is altered after incubation in substrates containing glyphosate and fipronil formulations.

Besides its crucial role during embryo development, eggshells are an essential bioindicator of environmental contaminants. However, the effects of contaminant exposure during incubation on the eggshell composition remain poorly known for freshwater turtles. Accordingly, we tested the effects of incubating the eggs of Podocnemis expansa in substrates containing glyphosate and fipronil formulations on the eggshell's level of mineral and dry matter, crude protein, nitrogen, and ethereal extract. Eggs were incubated in sand moistened with water contaminated with glyphosate Atar 48 at concentrations of 65 or 6500 µg/L, fipronil Regent 800 WG at concentrations of 4 or 400 µg/L, or the combination of 65 µg/L glyphosate and 4 µg/L fipronil and 6500 µg/L glyphosate with 400 µg/L fipronil. Exposure to the tested pesticides, alone or in association, altered the chemical composition of the eggshell of P. expansa, reducing the eggshell's moisture and crude protein content and increasing levels of ethereal extract. These changes may cause significant deficiencies in the mobilization of water and nutrients to the embryo, affecting the development and reproductive success of P. expansa.

Mutagenicity, hepatotoxicity, and neurotoxicity of glyphosate and fipronil commercial formulations in Amazon turtles neonates (Podocnemis expansa).

Pesticides are considered one of the main causes of the population decline of reptiles worldwide, with freshwater turtles being particularly susceptible to aquatic contamination. In this context, we investigated the potential mutagenic, hepatotoxic, and neurotoxic effects in neonates of Podocnemis expansa exposed to substrate contaminated with different concentrations of glyphosate and/or fipronil during embryonic development. Eggs collected from the natural environment were artificially incubated in sand moistened with pure water, water added with glyphosate Atar 48® at concentrations of 65 and 6500 µg/L (groups G1 and G2, respectively), water added with fipronil Regent® 800WG at 4 and 400 µg/L (groups F1 and F2, respectively) and, water added with the combination of 65 µg/L glyphosate and 4 µg/L fipronil or with 6500 µg/L glyphosate and 400 µg/L fipronil (groups GF1 and GF2, respectively). For mutagenicity analysis, we evaluated the frequency of micronuclei (MN) and other erythrocyte nuclear abnormalities (ENAs), while for evaluation of hepatotoxicity and neurotoxicity, livers and encephalon were analyzed for histopathological alterations. Exposure to pesticides, alone or in combination, increased the frequency of erythrocyte nuclear abnormalities, particularly blebbed nuclei, moved nuclei, and notched nuclei. Individuals exposed to fipronil exhibited congestion and inflammatory infiltrate in their liver tissue, while, in the encephalon, congestion, and necrosis were present. Our study confirms that the incubation of eggs in substrate polluted with glyphosate and fipronil causes histopathological damage and mutagenic alteration in P. expansa, highlighting the importance of using different biomarkers to evaluate the ecotoxicological effects of these pesticides, especially in oviparous animals.

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.

Diversity of Haemogregarine Parasites Infecting Brazilian Anurans, with a Description of New Species of Dactylosoma (Apicomplexa: Adeleorina: Dactylosomatidae).

PURPOSE: Brazilian anurans are considered the most diverse and species rich around the world. Although in recent years there has been a strong focus on research related to this group of animals, their parasites have not received the same attention. Thus, this study aimed to provide morphological and molecular data on haemogregarines biodiversity infecting Brazilian anurans. METHODS: During 2020, 116 anurans were collected from four Brazilian States and their blood and fragment of organs were screened for haemogregarine parasites. RESULTS: From the total, seven (6.03%) animals were found infected with species of Hepatozoon and Dactylosoma. Based on the morphological and molecular analysis, four anurans were found infected with Hepatozoon latrensis. The phylogenetic analysis has shown the isolates from this study grouping with the Brazilian anuran Hepatozoon clade, also with gene similarity ranging from 99.70 to 100% to H. latrensis isolates available on GenBank. Furthermore, three specimens (Trachycephalus typhonius, Leptodactylus latrans, and Rhinella diptycha) were infected with the same species of Dactylosoma (100% genetic similarity), with a genetic similarity of 98.56% to Dactylosoma piperis the only other species described in Brazil. In support of the molecular data, different morphological characters were observed in the blood smears as compared to D. piperis, suggesting that the species of Dactylosoma from the present study infecting three different species of Brazilian anurans is an undescribed species. CONCLUSION: Thus, this study increases the knowledge of Brazilian anuran blood parasites and demonstrates the importance of using integrative approaches for the diagnosis of haemoparasites.

Diversity of haemogregarine parasites infecting Brazilian snakes from the Midwest and Southeast regions with a description of two new species of Hepatozoon (Apicomplexa: Adeleorina: Hepatozoidae).

Although Brazil is a hotspot for snake species, there is a lack of information on the biodiversity of haemoparasites infecting these hosts. Thus, the present study aimed to bring new insights on the diversity of species of Hepatozoon (Apicomplexa: Adeleorina: Hepatozoidae) infecting Brazilian snakes from the Midwest and Southeast regions. The snakes were captured from 2018 to 2020 from the states of Mato Grosso, Mato Grosso do Sul, Goiás, and São Paulo. Three to five blood smears were made and the remaining blood sample was stored for further molecular analysis. Moreover, histopathological slides of the organs were stained with haematoxylin-eosin. Regarding molecular diagnosis, PCR was performed targeting different regions of the 18S rRNA gene of apicomplexan parasites. From the 13 free-living snakes screened, ten (76.92%) were found infected with Hepatozoon spp. Based on morphological and morphometric tools, five different morphotypes of species of Hepatozoon gamonts were detected. Molecular data and phylogenetic analysis support the morphological data, identifying five species of Hepatozoon from snakes, of which three species belong to previously described species, Hepatozoon cevapii, Hepatozoon cuestensis, and Hepatozoon quagliattus, with a genetic similarity of 100% (based on the 18S rRNA genetic marker). The present study identifies and describes two new species of Hepatozoon, Hepatozoon annulatum sp. nov. infecting the snake Leptodeira annulata and Hepatozoon trigeminum sp. nov. infecting the snake Oxyrhopus trigeminus. Thus, based on morphological and molecular data the present study provides new insights on haemogregarine diversity infecting Brazilian snakes from the Midwest and Southeast regions.

The exposure in ovo of embryos belonging to Amazonian turtle species Podocnemis expansa (Testudines) to commercial glyphosate and fipronil formulations impairs their growth and changes their skeletal development.

Pesticides are widely used in agricultural production; moreover, they can have direct and indirect effect on both flora and fauna. Aquatic organisms, among other animals, including reptiles, are mainly susceptible to contamination effects. Accordingly, the aim of the present study is to test the hypothesis that the incubation of Podocnemis expansa eggs in substrate added with glyphosate and fipronil formulations changes their viability, interferes with their growth and induces bone alterations. Eggs collected in natural environment were artificially incubated in sand moistened with water added with glyphosate Atar 48, at concentrations of 65 or 6500 µg/L (groups G1 and G2, respectively), and with fipronil Regent 800 WG at 4 or 400 µg/L (groups F1 and F2, respectively) or, yet, with the combination of 65 µg/L glyphosate and 4 µg/L fipronil, or with 6500 µg/L glyphosate and 400 µg/L fipronil (groups GF1 and GF2, respectively). The level of exposure to the herein assessed pesticides was quantified at the end of the incubation period; it was done by dosing its concentration in eggshells. Eggs exposed to the tested pesticides did not have their viability affected by it; however, all embryos exposed to the tested pesticides showed lowered body mass at hatch, as well as impaired development. In addition, bone malformation in the scleral ossicular ring was observed in individuals in groups F1, F2 and GF1. Pesticides accumulated in eggshells at concentrations related to exposure level. Thus, the recorded results have evidenced some remarkably relevant, and previously unknown, impacts associated with the exposure of a species listed as lower risk/conservation dependent, which spends most of its life in the water, to two widely used pesticides, at a very sensitive stage of its life, namely: egg incubation on land.

Evolutionary history or function? Which preponderates in the expression of the muscle mass of the thoracic limb in wild carnivorans?

Thoracic limbs are extremely versatile and exhibit informative characteristics about habits of the Carnivora order in the wild. Despite this relevance, comparative studies with quantitative variables on thoracic limb muscles are still scarce in carnivorans. The aims of this study were to measure the mass of the intrinsic muscles of the thoracic limb of neotropical species of the Carnivora order and to establish comparative conjectures. For this purpose, 39 thoracic limbs of 10 neotropical carnivorans species were dissected. The mass of each muscle was measured on a digital scale, muscles were grouped by function, and the mass average percentage that each functional group of muscles occupied in the thoracic limb was calculated. The data of the present study was added to that available in the literature for 22 other carnivoran species. Three groups of species were considered: Canidae, Musteloidea, and Feliformia. Comparatively, the eight canid species included in this analyses concentrate muscle mass proximally in the thoracic limb to prioritize essential cursoriality. The nine musteloids had more muscle mass in the distal muscles due to the demand for versatility and manual strength, and the 14 Feliformia species exhibited an intermediate trend. The analysis of clusters revealed a great overlap of the percentage distribution of muscle mass with the phylogeny previously established for carnivorans. It could be verified that the distribution of muscle masses meets the demand of the locomotor habits of the species up to a certain level, from which phylogeny begins to limit morphological adaptations.

Os membros torácicos são extremamente versáteis e exibem características informativas sobre os hábitos das espécies da ordem Carnivora em vida livre. A despeito desta relevência, estudos comparativos com variéveis quantitativas dos músculos do membro torácico são escassos em carnívoros. Os objetivos deste estudo foram aferir a massa dos músculos intrínsecos do membro torácico de espécies neotropicais da ordem Carnivora e estabelecer conjecturas comparativas. Para este fim, foram dissecados 39 membros torácicos de dez espécies de carnívoros neotropicais. A massa de cada músculo foi mensurada em uma balança digital, os músculos foram agrupados por função e calculou-se a massa percentual média a que cada grupo funcional de músculos correspondia no membro torácico. Os dados do presente estudo foram analisados conjuntamente às informações disponíveis na literatura para outras 22 espécies da ordem Carnivora. Três grupos de espécies foram considerados: Canidae, Musteloidea e Feliformia. Comparativamente, as oito espécies de canídeos incluídas nesta análise demonstraram concentração de massa muscular mais proximalmente no membro torácico em razão dos hábitos essencialmente cursoriais. As nove espécies da superfamília Musteloidea exibiram mais massa nos músculos distais devido à maior demanda por versatilidade e força manual. As 14 espécies da subordem Feliformia apresentaram um padrão intermediário. A análise de clusters revelou nítida sobreposição entre o percentual de distribuição da massa muscular com a filogenia previamente estabelecida para a ordem Carnivora. Verificou-se que a distribuição da massa dos músculos atende à demanda dos hábitos locomotores das espécies até um certo nível, a partir do qual a filogenia começa a limitar as adaptações morfológicas.