RESUMO

Salmonella infection can pose serious health issues, especially to children, elders or immunosuppressed humans. Wild populations of reptiles can reach Salmonella prevalence of up to 100% and the direct or indirect transmission from reptiles to humans have been extensively reported. Fernando de Noronha (FN) is an inhabited oceanic archipelago in the northeast coast of Brazil, with an economy based on tourism. The tegu (Salvator merianae) is the largest lizard native to South America and was introduced to the archipelago in the early 20th century. This study determines the prevalence, serotypes, antimicrobial resistance, and molecular epidemiology of Salmonella enterica in the tegu population from FN archipelago. Results show that S. enterica is widely distributed in the FN tegu population, with 43.8% prevalence. The bacteria were isolated from 70.5% of the sampled sites and a total of 15 serotypes were detected in 98 S. enterica isolates. Strains were further classified into 31 genotypes. Recaptured animals presented distinct genotypes in each season, demonstrating a seasonal strain turnover. Most S. enterica isolates from FN tegus presented low antimicrobial resistance. This is possibly due to geographical isolation of the island population, hampering contact with strains from livestock from the continent, where antimicrobial resistance is common.

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Using long-term, remote recordings of heart rate (fH) on fully recovered, undisturbed lizards, we identified several components of heart rate variability (HRV) associated with respiratory sinus arrhythmia (RSA): 1.) A peak in the spectral representation of HRV at the frequency range of ventilation. 2.) These cardiorespiratory interactions were shown to be dependent on the parasympathetic arm of the autonomic nervous system. 3.) Vagal preganglionic neurons are located in discrete groups located in the dorsal motor nucleus of the vagus and also, in a ventro-lateral group, homologous to the nucleus ambiguus of mammals. 4.) Myelinated nerve fibers in the cardiac vagus enabling rapid communication between the central nervous system and the heart. Furthermore, the study of the progressive recovery of fH in tegu following anesthesia and instrumentation revealed that 'resting' levels of mean fH and reestablishment of HRV occurred over different time courses. Accordingly, we suggest that, when an experiment is designed to study a physiological variable reliant on autonomic modulation at its normal, resting level, then postsurgical reestablishment of HRV should be considered as the index of full recovery, rather than mean fH.

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Abstract Cruzia lauroi sp. nov. is described from Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). The new species differs from all previously described species through several morphological characteristics: number of tooth like structures per row in the inner pharynx; and presence of unpaired papillae on the anterior border of the cloacal aperture. However, Cruzia lauroi sp. nov. is closest to C. tentaculata (Rudolphi, 1819), through having similar distribution of male caudal papillae, unpaired pre-cloacal papillae and females with an pre-equatorial vulva. Cruzia lauroi sp. nov. differs from C. tentaculata regarding smaller total body length of individuals, higher number of tooth like structures per row in the pharynx, greater size of diverticulum, smaller size of spicules and a more anterior vulva than in C. tentaculata; and the males do not have caudal alae. Cruzia mazza, C. travassosia, C. mexicana and C. testudines were considered to be species inquirendae, because their descriptions need more detailed taxonomic studies.

Resumo Cruzia lauroi sp. nov. é uma nova espécie descrita em Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). Essa nova espécie difere de todas as espécies descritas anteriormente por diferentes características morfológicas: pelo número de dentes por coluna longitudinal interna na faringe; pela presença de papila ímpar na borda anterior da cloaca. Entretanto, Cruzia lauroi sp. nov. possui similaridades com C. tentaculata (Rudolphi, 1819), por ter distribuição semelhante das papilas caudais dos machos, por possuir papila pré-cloacal ímpar e por possuir fêmeas com vulva pré-equatorial. Cruzia lauroi sp. nov. se difere de C. tentaculata em relação ao menor comprimento total do corpo dos indivíduos, pelo maior número de dentes por coluna longitudinal interna na faringe; pelo maior tamanho de divertículo; pelo menor tamanho de espículos; por possuir fêmeas com vulva mais próxima a extremidade anterior do que observado em fêmeas de C. tentaculata; e pelos machos não possuírem asa caudal. Cruzia mazza, C. travassosia, C. mexicana e C. testudines foram consideradas species inquirendae, pelo fato de suas descrições necessitarem de maior detalhamento taxonômico.

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RESUMO

Cruzia lauroi sp. nov. is described from Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). The new species differs from all previously described species through several morphological characteristics: number of tooth like structures per row in the inner pharynx; and presence of unpaired papillae on the anterior border of the cloacal aperture. However, Cruzia lauroi sp. nov. is closest to C. tentaculata (Rudolphi, 1819), through having similar distribution of male caudal papillae, unpaired pre-cloacal papillae and females with an pre-equatorial vulva. Cruzia lauroi sp. nov. differs from C. tentaculata regarding smaller total body length of individuals, higher number of tooth like structures per row in the pharynx, greater size of diverticulum, smaller size of spicules and a more anterior vulva than in C. tentaculata; and the males do not have caudal alae. Cruzia mazza, C. travassosia, C. mexicana and C. testudines were considered to be species inquirendae, because their descriptions need more detailed taxonomic studies.(AU)

Cruzia lauroi sp. nov. é uma nova espécie descrita em Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). Essa nova espécie difere de todas as espécies descritas anteriormente por diferentes características morfológicas: pelo número de dentes por coluna longitudinal interna na faringe; pela presença de papila ímpar na borda anterior da cloaca. Entretanto, Cruzia lauroi sp. nov. possui similaridades com C. tentaculata (Rudolphi, 1819), por ter distribuição semelhante das papilas caudais dos machos, por possuir papila pré-cloacal ímpar e por possuir fêmeas com vulva pré-equatorial. Cruzia lauroi sp. nov. se difere de C. tentaculata em relação ao menor comprimento total do corpo dos indivíduos, pelo maior número de dentes por coluna longitudinal interna na faringe; pelo maior tamanho de divertículo; pelo menor tamanho de espículos; por possuir fêmeas com vulva mais próxima a extremidade anterior do que observado em fêmeas de C. tentaculata; e pelos machos não possuírem asa caudal. Cruzia mazza, C. travassosia, C. mexicana e C. testudines foram consideradas species inquirendae, pelo fato de suas descrições necessitarem de maior detalhamento taxonômico.(AU)

Assuntos

RESUMO

Cruzia lauroi sp. nov. is described from Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). The new species differs from all previously described species through several morphological characteristics: number of tooth like structures per row in the inner pharynx; and presence of unpaired papillae on the anterior border of the cloacal aperture. However, Cruzia lauroi sp. nov. is closest to C. tentaculata (Rudolphi, 1819), through having similar distribution of male caudal papillae, unpaired pre-cloacal papillae and females with an pre-equatorial vulva. Cruzia lauroi sp. nov. differs from C. tentaculata regarding smaller total body length of individuals, higher number of tooth like structures per row in the pharynx, greater size of diverticulum, smaller size of spicules and a more anterior vulva than in C. tentaculata; and the males do not have caudal alae. Cruzia mazza, C. travassosia, C. mexicana and C. testudines were considered to be species inquirendae, because their descriptions need more detailed taxonomic studies.(AU)

Cruzia lauroi sp. nov. é uma nova espécie descrita em Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). Essa nova espécie difere de todas as espécies descritas anteriormente por diferentes características morfológicas: pelo número de dentes por coluna longitudinal interna na faringe; pela presença de papila ímpar na borda anterior da cloaca. Entretanto, Cruzia lauroi sp. nov. possui similaridades com C. tentaculata (Rudolphi, 1819), por ter distribuição semelhante das papilas caudais dos machos, por possuir papila pré-cloacal ímpar e por possuir fêmeas com vulva pré-equatorial. Cruzia lauroi sp. nov. se difere de C. tentaculata em relação ao menor comprimento total do corpo dos indivíduos, pelo maior número de dentes por coluna longitudinal interna na faringe; pelo maior tamanho de divertículo; pelo menor tamanho de espículos; por possuir fêmeas com vulva mais próxima a extremidade anterior do que observado em fêmeas de C. tentaculata; e pelos machos não possuírem asa caudal. Cruzia mazza, C. travassosia, C. mexicana e C. testudines foram consideradas species inquirendae, pelo fato de suas descrições necessitarem de maior detalhamento taxonômico.(AU)

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Several geographical areas where Salvator merianae is distributed in Argentina are included in regions with agricultural activity and exposed to pesticide formulations. Some pesticides could affect defense mechanisms being able alter structures of some components of immune and endocrine systems. To assess the potential effects of pesticides in this reptile under seminatural conditions, on the immune system and endocrine responses in S. merianae we analyzed several blood parameters. Total (TWBCC), differential (DWBCC) white blood cells count, heterophils/lymphocytes index (H/L), lobularity index (LI), natural antibodies (NAbs) titres, complement system (CS), and corticosterone concentration were analyzed in animals exposed to a mixture of cypermethrin (25%), glyphosate (66.2%) and chlorpyrifos (48%) formulations. In addition, body size was considered in these analyzes. TWBCC and NAbs revealed lower values in organisms exposed to pesticides respect to a control indicating a possible immunosuppression effect. Besides, the LI showed a greater number of lobes in organism exposed demonstrating symptoms of chronic infection. In addition, we observed a reduced growth in these animals possibly related to a less energy investment in body mass to maintain an active defense against pesticides. Finally, we found high levels of plasma corticosterone in animals exposed to mix formulation that could demonstrate neuroendocrine axis activation. Other parameters like DWBCC, H/L index and activity of CS showed no differences in treated animals respect to control group, which could indicate low sensibility of these parameters to the concentration of pesticides used. Our results provide evidence of the toxic effects of pesticides on different immune system parameters, but also a trade-off among these parameters, corticosterone levels and growth. In this way, we can conclude that the formulated pesticides applied widely and constantly in the areas occupied by S. merianae, would be affecting its immune and endocrine systems and therefore its ability to defend against external agents. This kind of studies is of great interest to know the possible responses of wild species to anthropogenic disturbances such as pesticide contamination.

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To define a protocol of anesthesia for long-duration invasive surgery in a lizard, eight young adult Argentine tegus ( Salvator merianae) of mean body weight 3.0 kg (interquartile range [IQR] 3.40-2.65) were anesthetized with a mixture of ketamine (K) and medetomidine (M) at 19°C, injected intramuscularly and equally distributed in the four limbs. As the experimental surgery procedure required a prolonged deep anesthesia with a good myorelaxation (between 16 and 21 hr), reinjections were required and reflexes were checked during surgery. Times for anesthetic induction, anesthetic reinjection, and recovery periods were recorded for five different combinations of ketamine-medetomidine: 1) 66 mg/kg K + 100 µg/kg M; 2) 80 mg/kg K + 100 µg/kg M; 3) 100 mg/kg K + 130 µg/kg M; 4) 125 mg/kg K + 200 µg/kg M; and 5) 150 mg/kg K + 200 µg/kg M. The effect on the recovery speed of the postoperative atipamezole injection was also evaluated. The median induction time was 30 (IQR 35-27.5) min with no statistical difference between all the concentrations tested. The first reinjection of half a dose was administered after a mean of 5 hr (5.64 hr, IQR 5.95-4.84) as were the subsequent reinjections of a quarter dose (3.99 hr, IQR 5.98-3.23). Intramuscular administration of the ketamine-medetomidine combination is a simple, rapid, and efficient anesthesia for long-term surgery (>12 hr). A mix of 100 mg/kg ketamine and 200 µg/kg medetomidine, with reinjections every 4 hr of half a dose of the previous injection can maintain a good quality of anesthesia for at least 16 hr. The injection of atipamezole after the surgery reverses the effects of medetomidine and permits a reduction of the recovery period.

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The heterogeneity of biotic and abiotic factors influencing fitness produce selective pressures that promote local adaptation and divergence among different populations of the same species. In order for adaptations to be maintained through evolutionary time, heritable genetic variation controlling the expression of the morphological features under selection is necessary. Here we compare morphological shape variability and size of the cephalic region of Salvator merianae specimens from undisturbed environments to those of individuals from disturbed environments, and estimated heritability for shape and size using geometric morphometric and quantitative genetics tools. The results of these analyzes indicated that there are statistically significant differences in shape and size between populations from the two environments. Possibly, one of the main determinants of cephalic shape and size is adaptation to the characteristics of the environment and to the trophic niche. Individuals from disturbed environments have a cephalic region with less shape variation and also have a larger centroid size when compared to individuals from undisturbed environments. The high heritability values obtained for shape and size in dorsal view and right side view indicate that these phenotypic characters have a great capacity to respond to the selection pressures to which they are subjected. Data obtained here could be used as an important tool when establishing guidelines for plans for the sustainable use and conservation of S. merianae and other species living in disturbed areas.

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The genus Salvator is widely distributed throughout South America. In Argentina, the species most abundant widely distributed is Salvator merianae. Particularly in Santa Fe province, the area occupied by populations of these lizards overlaps with areas where agriculture was extended. With the aim of established baseline values for four immunologic biomarkers widely used, 36 tegu lizards were evaluated tacking into account different age classes and both sexes. Total leukocyte counts were not different between age classes. Of the leucocytes count, eosinophils levels were higher in neonates compared with juvenile and adults; nevertheless, the heterophils group was the most prevalent leukocyte in the peripheral blood in all age classes. Lymphocytes, monocytes, heterophils, azurophils and basophils levels did not differ with age. Natural antibodies titres were higher in the adults compared with neonates and juveniles lizards. Lastly, complement system activity was low in neonates compared with juveniles and adults. Statistical analysis within each age group showed that gender was not a factor in the outcomes. Based on the results, we concluded that S. merianae demonstrated age (but not gender) related differences in the immune parameters analyzed. Having established baseline values for these four widely-used immunologic biomarkers, ongoing studies will seek to optimize the use of the S. merianae model in future research.

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Até o momento quinze espécies de lagartos foram registradas para a Serra do Ouro Branco, localizada na porção sul da Cadeia do Espinhaço, região onde a diversidade e o estado de conservação desse grupo zoológico são pouco conhecidos. Nesta Serra estão inseridos o Parque Estadual da Serra do Ouro Branco e o Monumento Natural Estadual de Itatiaia, unidades de conservação criadas em 2009. Para o êxito dos planos de conservação e manejo de unidades de conservação é fundamental o envolvimento da população local ao longo de todo processo, desde a criação, implementação até a manutenção futura. Neste sentido, visando a conservação da fauna, foi investigado, sob uma perspectiva etnozoológica, o conhecimento local relativo aos lagartos da Serra do Ouro Branco. Participaram desse estudo 107 moradores de três povoados localizados no entorno das duas unidades de conservação. Os dados foram obtidos por meio de entrevistas semi-estruturadas, lista livre e testes projetivos utilizando fotografias. Foram reconhecidas oito espécies por seis nomes populares. Estas incluem formas semifossoriais e de difícil visualização, como Heterodactylus imbricatus e Ophiodes striatus. As espécies do gênero Enyalius foram conhecidas por "cambaleão". Tropidurus torquatus e Tropidurus itambere foram denominados "calango". A lagartixa de parede, designada por "briba" (Hemidactylus mabouia), foi associada à transmissão de doença de pele "cobreiro". Heterodactylus imbricatus e Ophiodes striatus, reconhecidas como "cobra de patas" e "cobra de vidro", respectivamente, foram consideradas serpentes e, assim como estas, são mortas quando avistadas. O teiú (Salvator merianae) abrangeu a maior frequência de relatos, tendo sido capturado no passado, tanto para fins alimentares, quanto medicinais. Em função de relações conflituosas ligadas à predação de animais de criação, os teiús acabam sendo mortos. O acesso ao atendimento médico junto às mudanças sociais das comunidades parece ter contribuído para a redução do uso de animais para fins medicinais e alimentares, resultando em uma diminuição ou perda de práticas locais de usos de lagartos nessas comunidades. Os entrevistados reconheceram aproximadamente 50% dos lagartos registrados para a região da Serra do Ouro Branco, Nesse contexto estratégias de conservação, elaboradas de forma participativa, serão fundamentais no sentido de reforçar a importância desta fauna para a manutenção dos processos ecológicos da Serra do Ouro Branco, além de possibilitar o envolvimento dos moradores em iniciativas de conservação.

Up until the present moment, fifteen species of lizards were registered in Serra do Ouro Branco localized in the south portion of Cadeia do Espinhaço, place where the diversity and the state of conservation of this zoological group are little known. This area comprises the Serra do Ouro Branco State Park and the Natural State Monument of Itatiaia, conservation units created in 2009. For the success of the conservation plans and management of conservation units, it is essential that the local population be involved along the whole process, from its creation, implementation through its future maintenance. Accordingly, in this present work, the local knowledge of lizards from Serra do Ouro Branco was investigated under an ethnozoological perspective. One hundred and seven dwellers from three communities located in the surroundings of the conservation units participated in this research. The data were obtained through semi-structured interviews, free list and projective tests containing pictures. Eight species were identified with six popular names. These species include semi-fossorial and hard-to-see forms such as Heterodactylus imbricatus and Ophiodes striatus. The species of the genus Enyalius were called "cambaleão". Tropidurus torquatus and Tropidurus itambere were named "calango". The wall lizard (Hemidactylus mabouia) designated as "briba" was associated with the transmission of skin disease, or "cobreiro". Heterodactylus imbricatus and Ophiodes striatus identified as "cobra de patas" and "cobra de vidro", respectively, were considered snakes and are, in general, killed when sighted. Teiú (Salvator merianae) comprised a higher frequency of reports, being captured in the past both for feeding and for medicinal purposes. Due to conflictual relations related to the predation of livestock, teiús (Salvator merianae) are at times killed. The access to medical care along with the communities social changes seem to have contributed to the reduction in the use of animals for medicinal and feeding purposes, resulting in a reduction or loss of local practices of the use of lizards in these communities. The interviewees identify approximately 50% of the lizards registered for the region of Serra do Ouro Branco. Conservation strategies, created in a participatory way, are going to be essential in the sense of highlighting the importance of this fauna for the maintenance of the ecological processes of Serra do Ouro Branco, besides making possible the involvement of local dwellers in conservation initiatives.

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