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.

Venous blood gases and electrolyte values of captive red foot tortoise (Chelonoidis carbonarius)

Blood gas analysis reflects the exchange of oxygen and carbon dioxide in the lungs. This test provides important information, since the relationship between these gases has a direct impact on the acid-basic balance in the body. Given the significance of blood gas analysis in Brazilian reptiles, this study set out to establish temperature-corrected and uncorrected reference intervals for venous blood gas measurements in Chelonoidis carbonarius, and to compare values between females and males. In this study, 19 animals were used, 8 males and 11 females. Blood samples were collected from the dorsal coccygeal vein, and the analyses were performed immediately after blood sample collection. The following parameters were measured: pH, PO2, HCO3-, TCO2, BEecf, Na, K, ICa, and Glu, and were compared between females and males. Additionally, pH, pCO2, and pO2 values were compared with and without temperature correction. Oxygen saturation and Na levels were significantly higher (p<0.05) in males. Furthermore, it was possible to infer that the lower the body temperature relative to the environmental temperature, the larger the difference in pH following temperature correction.

Epidemiological survey of infectious agents in free-ranging maned wolves (Chrysocyon brachyurus) in Northeastern Brazil

Infectious diseases are one of the most concerning threats to maned wolves (Chrysocyon brachyurus) due to the potential impact on free-ranging populations. The species is currently classified as vulnerable according to the national list of threatened species and occurs mainly in open habitats, such as the Cerrado, a tropical savannah, which comprises its main distribution area in Brazil. In the northeastern region, it occurs in the Cerrado of Bahia, Piauí, Maranhão, and Tocantins states. Therefore, this study aimed to investigate the occurrence of infectious agents in Chrysocyon brachyurus through an epidemiological assessment of free-ranging individuals in western Bahia, specifically in the Barreiras microregion, a Cerrado area intensely fragmented and anthropized by agricultural activity. Eleven specimens were evaluated for serological titration, antigen research, and genetic material research for canine distemper virus (CDV), canine parvovirus (CPV), adenovirus-canine-type 1 (CAdV-1), canine coronavirus (CCoV), Leptospira interrogans and Toxoplasma gondii from 2020 to 2022. In addition to maned wolves, domestic dogs were also evaluated and tested. All maned wolves (100%) evaluated by the dot-ELISA technique exhibited immunoglobulin M (IgM) and seven (64%) exhibited immunoglobulin G (IgG) against CDV and CPV, while 100% exhibited IgG against CDV when using the immunochromatographic technique. Regarding CAdV-1, 90% were seropositive for IgG, while 64% exhibited IgG against T. gondii. Nine dogs from the region were also sampled, and all (100%) exhibited IgM and IgG against CDV and CPV. For IgG against T. gondii and against CAdV-1, 90% of the animals were seropositive. Molecular evaluation yielded negative results for all maned wolves and dogs assessed for CAdV-1, CDV, and T. gondii, as well as the CCoV antigen. These data indicate the occurrence of viral agents and Toxoplasma gondii in maned wolves and dogs, suggesting circulation in both populations.

Traumatic chylothorax in urbanized free-ranging black-tufted marmosets (Callithrix penicillata)

After fatal traumatic injuries, three urbanized free-ranging marmosets developed a milky white or pink-white thoracic alkaline effusion with high specific gravity, triglyceride levels, and predominance of small lymphocytes. Chylothorax is an uncommon thoracic fluid accumulation in animals and humans and has not been reported in free-ranging non-human primates.

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.

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.

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.

Prenatal effects of alprazolam treatment on the immature cerebellum of rats

The use of benzodiazepines (BZDs) during pregnancy, especially alprazolam, is common and its impact on the fetal neural tissue is not known. In this sense, the present study aimed to investigate the effects of prenatal treatment with alprazolam on the cerebellum of Wistar rat pups. Thirty animals (24 females and six males, CEUA protocol 014/17) were separated into pairs for copulation. Females were divided into three groups: Control (CT), treatment 1 (T1, 1.25 mg per animal), and treatment 2, which is an overdose (T2, 30 mg per animal). Alprazolam was administered 10 days before copulation and throughout pregnancy. We evaluated the number and weight of pups and the macroscopic changes in the brain. Eight neonates (n = 8) from each group were used in the following analyses: Cellular and chromatin density, gliosis, synaptic density, inflammation, and oxidative stress. The results showed no significant differences regarding the number of pups, body weight, and macroscopic changes. The morphological study focused on the external granular layer (EGL) that is presented only in the immature cerebellum. Here, we detected more cells after alprazolam treatment; the T2 group showed large nuclei and some pyknotic nuclei; also, both treated groups presented an increase in the euchromatin density compared with the control. The molecular and biochemical analyses used the total protein extract of the entire cerebellum and showed an increased expression of Iba-1 and NF-κBp65 but without indication of inflammation or degeneration in the T1 group. Overdose of alprazolam presented an increased level of oxidative degradation of lipids. The treatment with alprazolam during pregnancy involved cellular and molecular changes in the immature cerebellum.

Molecular detection of Leucocytozoon in red-legged seriemas (Cariama cristata), a non-migratory bird species in the Brazilian Cerrado

Avian Haemosporidian parasites - Plasmodium, Haemoproteus, Leucocytozoon and Fallisia - have a wide distribution except for Antarctica. Leucocytozoon sp. has been poorly described in Brazil, and few studies have indicated infections in birds from the Atlantic Forest, Pantanal, Pampa and Amazon biomes. This study describes, for the first time, the occurrence of Leucocytozoon infection in red-legged seriemas (Cariama cristata) in the Brazilian savanna (Cerrado biome) using molecular diagnosis. Leucocytozoon spp. lineage CARCRI01 was detected in three C. cristata, a non-migratory bird, confirming transmission in mid-elevation areas in central Brazil. Further studies are needed to certify whether infections in red-legged seriemas were not abortive and to elucidate Leucocytozoon infection at low altitudes in the Brazilian lands.

Wild fauna received by the Wild Animal Screening Centre and referred to the Veterinary Hospital of the University of Brasília

Abstract The aim of this work was to analyze records from two institutions that work with wild animals throughout 2018. Data were obtained from the animals received by the Wild Animal Screening Centre of Federal District (CETAS-DF), Brazil, referring to the type of admission and destination, species, as well as animals that required veterinary care and were referred to the Wild Animal Sector of the Veterinary Hospital of the University of Brasilia (HVet-UnB) with description of the main conditions and temporal analysis. Of the 7,603 animals that were admitted to CETAS-DF (6,646 birds, 461 mammals and 496 reptiles), 1,028 individuals (13.52%) required veterinary medical care and were referred to HVet-UnB. The class of animals that most needed assistance was birds (765), followed by mammals (225) and reptiles (37). Unlike other fauna diagnostic surveys from environmental agencies, this is the first study that correlates the numbers of animals received by a CETAS and that were referred for veterinary medical follow-up. The high number of wild animals that require referral to specialized institutions reinforces the need to establish agreements and structure for veterinary medical treatment and subsequent rehabilitation of these specimens as part of an action plan for the conservation of biodiversity in the country.

Fauna silvestre recebida pelo Centro de Triagem de Animais Silvestres e encaminhada para o hospital veterinário da Universidade de Brasília

Resumo O trabalho teve como objetivo analisar registros de duas instituições que trabalham com animais silvestres ao longo do ano de 2018. Foram obtidos dados dos animais recebidos pelo Centro de Triagem de Animais Silvestres do Distrito Federal (CETAS-DF), referentes ao tipo de entrada e destinação, espécies, bem como animais que necessitaram de atendimento médico veterinário e foram encaminhados ao Setor de Animais Silvestres do Hospital Veterinário da Universidade de Brasília (HVet-UnB) com descrição das principais afecções e análise temporal. Dos 7.603 animais que deram entrada no CETAS-DF (6.646 aves, 461 mamíferos e 496 répteis), 1.028 indivíduos (13,52%) necessitaram de atendimento médico veterinário e foram encaminhados ao HVet-UnB. A classe de animais que mais precisou de assistência foi a de aves (765), seguida de mamíferos (225) e de répteis (37). Diferente de outros levantamentos de diagnóstico de fauna de órgãos ambientais, este é o primeiro estudo que correlaciona os números de animais recebidos por um CETAS e que foram encaminhados para acompanhamento médico veterinário. O alto número de animais silvestres que demandam encaminhamento para instituições especializadas reforça a necessidade de estabelecimento de acordos e estrutura de tratamento médico veterinário e posterior reabilitação desses exemplares como parte de plano de ação de conservação da biodiversidade no país.

Encephalic Toxoplasm in a White-Eared Possum (Didelphis albiventris)

Background: Toxoplasmosis is caused by Toxoplasma gondii, an obligate intracellular protozoan that belongs to the Aplicomplexa phylum, coccidian subclass, and affects all warm-blooded animals. The role of opossums in the epidemiology of toxoplasmosis in Brazil is not fully understood, and there are very few descriptions of toxoplasmosis lesions in these animals. This report describes the anatomopathological, molecular and immunohistochemical findings of a case of encephalic toxoplasmosis in free-living white-eared possum (Didelphis albiventris).Case: A young male opossum (D. albiventris), was treated at the Veterinary Hospital of Wild Animals of the University of Brasília, Federal District. The animal was apathetic, uncoordinated, reluctant to move, and had an exposed proximal fracture in the left radius and ulna with laceration of muscles and adjacent tendinous structures. Amputation on the left thoracic limb was performed followed by analgesia and antibiotic therapy. The environment is frequented by other wild animals, and stray cats have access to the patio of the building. Twenty-five days after arriving at the hospital, the animal was found dead in its cage. After death, a necropsy was performed. Organ fragments from the abdominal cavity, thoracic and central nervous system were collected, processed routinely for histology and stained with hematoxylin and eosin. Macroscopic lesions in the central nervous system were not observed. On microscopy, the brain showed moderate random glial nodules throughout the neuropil associated with the presence of spherical to elongated parasitic cysts of about 20 µm, with a thin wall and with its interior full of bradyzoites, consistent with Toxoplasma gondii. There was also moderate fibrinoid necrosis and moderate multifocal lymphoplasmacytic infiltrate surrounding the blood vessels (perivascular cuffs) To investigate the etiology of the brain injury, brain sections were subjected to immunohistochemistry (IHC) and real-time polymerase chain reaction (qPCR) technique for detection of T. gondii and Neospora caninum. Immunostaining for T. gondii in the cyst wall and in bradyzoites and negative immunostaining for N. caninum. qPCR was positive for T. gondii and negative for N. caninum.Discussion: Diagnosis of encephalic toxoplasmosis in a Didelphis albiventris was possible based on histopathological, immunohistochemical and molecular findings. The morphological classification of the brain lesion was important for the diagnosis. Brain toxoplasmosis in opossums usually results in focal areas of malacia on macroscopy and focally extensive necrosis on microscopy, neutrophil infiltrate, calcified necrotic material, and perivascular cuffs of lymphocytes and plasma cells. In the present case, similar histopathological lesions were noted, but no significant macroscopic changes were observed. The etiology here was defined by immunohistochemistry and qPCR, techniques proven to be useful and with good specificity for diagnosing toxoplasmosis in mammals. It is believed that the positive immunohistochemical and molecular result for Toxoplasma gondii together with the negative result for Neospora caninum were conclusive for the diagnosis. Thus, we demonstrate here a post mortem diagnosis of toxoplasmosis in a free-living synanthropic opossum and the use of anatomopathology, immunohistochemistry and real-time polymerase chain reaction as a diagnostic option for this disease in opossums. Keywords: Toxoplasma gondii, marsupial, immunohistochemistry, Real time PCR, protozoal encephalitis.Título: Toxoplasmose encefálica em um gambá-de-orelha-branca (Didelphis albiventris)Descritores: Toxoplasma gondii, marsupial, imuno-histoquímica, Real time PCR, encefalite protozoal.

TRATAMENTO DE TRAUMATISMO CRANIOENCEFÁLICO EM Nasua nasua (Linnaeus, 1766): RELATO DE CASO

Animais silvestres podem ser expostos a diversas agressões de caráter traumático, como por exemplo, quedas, atropelamentos e predação. Tais eventos podem originar diversas lesões, dentre elas, o traumatismo cranioencefálico (TCE), que é definido como um trauma na cabeça que afeta o sistema nervoso central (CUNHA, 2017). O objetivo do presente trabalho é relatar um caso de traumatismo cranioencefálico em um quati (Nasua nasua). Foi atendido um exemplar de quati macho, jovem, no Setor de Animais Silvestres do Hospital Veterinário da Universidade de Brasília,  que apresentava hipoatividade e hiporreflexia. Ao exame físico, foi observada fissura no palato em região média e laceração em região de face. A imagem radiográfica permitiu observar fratura no osso frontal e confirmou a fissura no palato. A abordagem terapêutica inicial foi realizada com fluidoterapia com ringer lactato (50 mL, SC, dose única), manitol 20% (5 mg/kg, IV, BID) e tramadol 50 mg/mL (6 mg/kg, IM, BID)  por quatro dias. Concomitantemente, houve a utilização de meloxicam 0,2% (0,1 mg/kg, IM, SID) e dipirona 500 mg/mL (25mg/kg, VO, BID) por dez dias. No sexto dia de tratamento, iniciou-se o uso de propentofilina 10 mg/mL (3 mg/kg, VO, BID) por quinze dias. Foi observada melhora do quadro clínico inicial após o terceiro dia de tratamento. Após dois meses, foi observada resolução da fratura e então o animal foi considerado apto para retorno à natureza e encaminhado ao CETAS-DF para soltura. No TCE ocorre ativação de vias bioquímicas que intensificam os danos e elevam a pressão intracraniana (PIC), que compromete a perfusão encefálica e é considerada como a principal causa de óbito. Para uma melhor terapêutica recomenda-se exame neurológico completo e auxílio de exames de imagem. A prioridade deve ser a estabilização crânio cervical, além da manutenção de pressão de perfusão cerebral e suprimento de oxigênio adequados. Evitar a hipovolemia, a hipóxia e a hiperglicemia são essenciais para um melhor prognóstico. O manitol possui efeito osmótico e age na diminuição da viscosidade sanguínea e na indução da diurese, o que promove a vasoconstrição cerebral e diminui o risco de edema cerebral. Já a propentofilina auxilia no aumento da perfusão sanguínea e consequente oxigenação cerebral. O controle da dor também está ligado diretamente à diminuição da PIC, por isso analgésicos e anti-inflamatórios não esteroidais são recomendados nos protocolos terapêuticos de TCE. O uso de opioides pode causar efeitos adversos, como hipotensão e depressão respiratória e, consequente, aumento da PIC, porém quando utilizado com doses analgésicas são considerados seguros. Em casos graves, a intervenção cirúrgica pode ser recomendada (SANDE; WEST, 2010). O tratamento de TCE deve ser imediato e agressivo, pois apesar do prognóstico reservado, os animais podem se recuperar de forma sistêmica e neurológica se as anormalidades forem identificadas precocemente, conforme o quati deste presente relato.

USO DE NITAZOXANIDA NO TRATAMENTO DE TRICOMONÍASE EM AVES: RELATOS DE CASOS

Trichomonas sp. é um protozoário flagelado causador da tricomoníase. Esse parasita afeta principalmente os tratos digestivo superior e respiratório de aves, com ocorrência comum em espécies das ordens Columbiformes, Falconiformes e Psittaciformes (SILVA, 2017). O objetivo do presente trabalho é relatar três casos resolução da tricomoníase em aves tratadas com nitazoxanida. Foram atendidos no Setor de Animais Silvestres do Hospital Veterinário da Universidade de Brasília, dois espécimes de Caracara plancus e um de Ramphastos tocos, jovens e de sexo indeterminado. Ao exame físico, os dois carcarás se apresentavam em estação e resistiram à manipulação, enquanto o tucano se mostrou pouco responsivo e apático. Os animais apresentavam placas caseosas esbranquiçadas em cavidade oral as quais foram coletadas através de swab estéril e enviadas para exame parasitológico, com confirmação da presença de Trichomonas sp. Na abordagem inicial todos receberam fluidoterapia com ringer lactato (3% do peso vivo, SC, SID) durante três dias. No primeiro exemplar de carcará, a primeira abordagem terapêutica  para tricomoníase foi realizada com metronidazol 50mg/mL (50mg/kg, VO, SID), porém não se mostrou efetiva, dado que o segundo exame parasitológico apontou a persistência do protozoário. Como segunda abordagem terapêutica foi realizada a administração de nitazoxanida 20 mg/mL (42mg/kg, VO, BID) durante sete dias, concluindo o tratamento do animal com êxito. O outro exemplar de carcará e o tucano foram tratados unicamente com nitazoxanida 20mg/mL (42mg/kg, VO, BID) durante sete dias logo após o primeiro resultado positivo para o parasita, com resolução rápida da infestação.  As aves permaneceram no hospital para melhor recuperação de escore corporal e, quando consideradas aptas, foram encaminhadas ao CETAS-DF para destinação. A tricomoníase é transmitida de forma direta pelo contato entre os animais sadios e os carreadores, por ingestão de água, alimento e fômites.  Dito isto, populações de animais silvestres são extensivamente afetadas devido à alta circulação nos ambientes e o compartilhamento de espaços durante forrageamento. A prevalência de Trichomonas sp. em aves de rapina de vida livre também seria justificada por seus hábitos alimentares devido à predação de columbiformes, que podem carrear o protozoário sem apresentarem sinais clínicos. Existem poucos relatos de tricomoníase em tucanos, mas são mais escassos. A nitazoxanida possui atividade antimicrobiana de amplo espectro, sendo uma medicação eficaz contra helmintos e protozoários intestinais. Sua ação está relacionada ao bloqueio da reação de transferência de elétrons dependente da enzima piruvato-ferredoxina oxidoredutase, essencial para o metabolismo anaeróbico. Este princípio ativo e seu metabólito ativo tizoxanida são capazes de inibir o crescimento de formas trofozoítas de Trichomonas sp. in vitro. Ainda são escassos estudos acerca do uso da nitazoxanida no tratamento de tricomoníase em aves (EEDIC, 2016), por isso, relatos como o presente são importantes como fonte de informações para opções terapêuticas na medicina de animais silvestres. Nos casos descritos, o uso de nitazoxanida foi eficaz no tratamento de tricomoníase de dois exemplares de carcará e um de tucano, e pode ser considerado como opção de tratamento para demais aves.

Nasal Melanophoroma in a Captive Green Iguana (Iguana Iguana)

Green iguanas are arboreal lizards, common as pet animals and in captivity. Knowledge of neoplasms in iguanas is scarce, and a challenge to their prevention, treatment, and prognosis. A captive green iguana showed a pigmented nasal exophytic neoplasm. Tumor cells were spindle-shaped to epithelioid with a variable amount of dark-brown or black granular melanin within the cytoplasm, and also presented cytoplasmic positivity for Melan-A and S100. Transmission electron microscopy evidenced intracytoplasmic melanosomes and premelanosomes and provided a definitive diagnosis of a nasal melanophoroma. Full characterization of the clinicopathological and ultrastructural features of the melanophoroma may contribute to the limited knowledge concerning cutaneous neoplasms in green iguanas.

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.

Development of scleral ossicles in Podocnemis expansa (Testudines: Podocnemididae) embryos exposed to atrazine

Understanding the effects of atrazine exposure on embryo development in oviparous animals may provide important data regarding the impacts of agrochemical use on wildlife and the ecosystem. This study set out to determine the effects of embryonic atrazine exposure on the development of osseous and cartilaginous components of scleral ossicles in Podocnemis expansa. Eggs were collected at the Environmental Protection Area Meandros do Rio Araguaia, Brazil, and artificially incubated in sand treated with solutions containing 2, 20 or 200 µg/L of atrazine. Sixty embryos were collected per treatment throughout the incubation period. Embryos were diaphanized with potassium hydroxide (KOH) and stained with Alizarin Red S and Alcian blue (bone and cartilage tissue respectively). Scleral ossicles were then counted and examined for skeletal abnormalities at different stages of embryonic development. Scleral ossicle counts were significantly reduced in P. expansa embryos treated with 200 μg/L atrazine solution. Rudimentary ossicles and gaps were also noted in embryos exposed to atrazine concentrations of 2 μg/L or 200 μg/L. Findings of this study emphasize the relevance of ecotoxicological investigations in determining the impacts of agrochemicals on native fauna.

Ontogeny of the Postcranial Axial Skeleton of Melanosuchus niger (Crocodylia, Alligatoridae)

This study proposes the description of the development of the postcranial axial skeleton, including vertebrae, gastralium, ribs, sternum, and interclavicle, in Melanosuchus niger. Six nests were marked and two eggs removed from each nest at 24-hr intervals until hatching. For posthatching evaluation, 30 hatchlings were kept in captivity and one exemplar was euthanized at three-day intervals. Samples were diaphanized using potassium hydroxide (KOH), alizarin red S, and Alcian blue. A routinely generally used method was applied for histological evaluation. It was difficult to define in which vertebrae the development of cartilaginous centers began, but it was possible to observe that this condensation advanced in the craniocaudal direction. The condensation started in the vertebral arches and was visibly stronger in the cervical and dorsal regions, advancing to the lumbar, sacral and, last, to the caudal region. The atlas showed a highly different morphology compared with the other cervical vertebrae, with a short intercenter, two neural arches, and a proatlas. The ossification process began in the body of cervical vertebrae III to VIII and alizarin retention decreased in the last vertebrae, indicating a craniocaudal direction in bone development, similar to cartilage formation. In the histological sections of gastralium and interclavicles of M. niger at several development stages, it was possible to observe that these elements showed intramembranous development. Anat Rec, 301:607-623, 2018. © 2017 Wiley Periodicals, Inc.

EFEITOS DA ADMINSTRAÇÃO DO MIDAZOLAM EM DOSES DIFERENTES EM JIBOIAS Boa constrictor LINNAEUS, 1758 (SQUAMATA: BOIDAE)

Resumo Objetivou-se comparar os efeitos de duas doses de midazolam em Boa constrictor. Utilizaram-se 20 jiboias, divididas em dois grupos. O grupo 1 (G1), composto por dez animais, recebeu 1 mg/kg de midazolam e o grupo 2 (G2), também com dez animais, 2 mg/kg, pela via intracelomática. Os animais do G1 apresentaram déficit de tônus da cabeça, tônus muscular, manipulação e locomoção por 3,89 ± 1,18 horas e os representantes do G2 por 5,47 ± 2,08 horas. Nenhuma jiboia, em ambos os grupos, manifestou ausência de reação postural de endireitamento ou alcançaram sedação profunda; entretanto, observou-se redução da agressividade, intenso relaxamento muscular e uma dificuldade de serpentear em todos os exemplares. O tempo de retorno às condições pré-sedativas foi de 4,65 ± 1,22 horas para o G1 e de 6,2 ± 2,37 horas para o G2. Não foram observadas diferenças significativas nas avaliações da frequência cardíaca e respiratória entre os grupos. Concluiu-se assim que 1 mg/kg de midazolam provoca nas jiboias o mesmo efeito que 2 mg/kg, porém na menor dose o tempo de recuperação é menor, podendo ser utilizado para a contenção farmacológica de Boa constrictor, ou em associações que visem um efetivo relaxamento muscular.