Search Results (763)

Atherosclerosis is highly prevalent among captive psittacine populations and is a frequent cause of veterinary consultations. Ante-mortem diagnosis remains challenging, but the serum lipoprotein analysis has been suggested as a useful tool for identifying associated risk factors and improving understanding of its pathogenesis. Unlike in humans, the relationship between lipoproteins and atherosclerosis in parrots has not been clearly established. This retrospective cohort study analyzed n = 1199 blood samples from 692 parrots across 14 genera to establish reference intervals for high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) following ASVCP guidelines. Lipoprotein levels were evaluated in relation to factors such as genus, age, sex, diet, reproductive status, body condition score, and atherosclerosis prevalence (diagnosed by endoscopy and/or necropsy). The results demonstrated genus-specific differences and significant associations between LDL-C and atherosclerosis, with non-HDL-C showing a similar, less pronounced, trend. Higher LDL-C values were measured in the presence of moderate-severe atherosclerosis. Birds on seed diets had higher lipoprotein levels and were more likely to be diagnosed with atherosclerosis in comparison to birds fed a pelleted or extruded diet. The role of HDL-C remained less conclusively defined. The results of this study provide a foundational framework for the future use of lipoprotein analysis in parrot medicine, offering novel insights into the management of cardiovascular health in pet parrots. Full article

Spinal deformities—such as kyphosis, scoliosis, and lordosis—are observed across all major vertebrate groups. Reports in wild reptiles are increasing but are mainly published in natural history notes as curiosities, with little exploration of their aetiology, pathology, prevalence, or consideration of potential ecological, evolutionary, and life history implications. Addressing this gap, I compiled the most comprehensive database to date by reviewing the peer-reviewed and grey literature and collecting unpublished records via standardised social media inquiries. I identified 690 observations from 146 sources, covering 109 reptile species in 24 families across 37 countries. Spinal deformities appear across all major reptile clades, though Testudines are over-represented (78.6% of all observations and 42.2% of all species). A phylogenetic meta-analysis of 54 effect sizes from 37 species yielded a global prevalence estimate of 0.21%, with no significant effects of phylogeny, habitat use, or habitat type detected, possibly due to dataset limitations. However, kyphosis was more common in (semi)aquatic Testudines, whereas scoliosis was more frequent in terrestrial squamates. Although deformities may impair key life history traits, supporting evidence remains scarce. The findings highlight the understudied nature of spinal deformities in wild reptiles and underscore the need for standardised, ecologically informed reporting to better understand their causes and consequences. Full article

The Chiapas Highlands of Mexico represent a critical center of herpetofaunal diversity and endemism within Mesoamerica. This study provides the first comprehensive inventory of amphibians and reptiles in the Mexican part of this biogeographic province, documenting 354 species, 112 amphibians, and 242 reptiles. Amphibian richness is highest in the families Hylidae, Plethodontidae, and Craugastoridae, whereas reptile richness is highest in the families Dipsadidae and Colubridae. Ninety-eight species are endemic to the Chiapas Highlands, with forty restricted to its Mexican portion. The herpetofauna of the Chiapas Highlands shows a high level of endemism. A higher proportion of reptile species are shared with neighboring provinces than amphibians. Conservation assessments reveal that 64 species are listed as Vulnerable, Endangered, or Critically Endangered on the International Union for Conservation of Nature’s (IUCN) Red List, 39 species are classified as Threatened (A) or Endangered (P) under Mexican environmental legislation, and 98 species are considered high-risk according to the Environmental Vulnerability Score (EVS), with habitat loss and chytrid fungi identified as principal threats. Our summary and synthesis of its amphibian and reptile species highlights the Chiapas Highlands as a biogeographic and ecological hotspot deserving urgent conservation attention. Full article

The adoption of exotic animals as pets is increasing across Europe. This study explores the human–chelonian relationship in the Italian population, specifically the motivations for acquiring reptiles as pets and the nature of the emotional bonds between guardians and chelonians. A total of 91 chelonian guardians replied to an online survey. Data was analyzed through a mixed-methods approach combining quantitative and qualitative analyses. Most participants (85.7%) owned Hermann’s tortoises (Testudo hermanni), having received them as gifts (50.5%) or purchased them (31.9%). Pet chelonians living outdoors had an almost five times higher odds of being reported as non-family members compared to those with indoor access (OR = 4.90, 95% CI = 1.34–23.41, p = 0.02). No significant relationship was detected between other demographic factors and bond type. When asked whether they consider their pet a family member, 70 out of 91 participants reported information for both their reptile and dog/cat. Among these, pets were seen as family members for 44.3% of chelonians and 92.4% of dogs/cats. In turn, qualitative responses from 85 participants showed that 45% expressed a strong emotional connection to their pet chelonians, using language denoting affection, love, and fascination. These findings suggest that, while emotional bonds between guardians and chelonians may be less interactive and intimate than those with conventional pets, they nonetheless reflect a meaningful bond rooted in personal values of entertainment, convenience, and duty of care. Full article

Investigating altitudinal distribution patterns of species richness represents a fundamental research objective in biogeography and community ecology. Hainan Island has tropical rainforests ranging from sea level to >1800 m a.s.l., with various animal species, including reptiles such as geckos. Information on the altitudinal distribution patterns of animal diversity on Hainan Island is limited. Thus, from October 2020 to June 2023, we surveyed Gekkonidae species on Diaoluo Mountain and Jianfeng Ridge in the Hainan Tropical Rainforest National Park using a line transect method. The two study sites were divided into seven altitudinal zones at intervals of 150 m from 31 to 1080 m a.s.l. We tested correlations between abundance and species diversity indices and altitude. Five gecko species were identified. The endemic Gekko similignum mainly occurred at high-altitude areas on both mountains, whereas Hemidactylus frenatus occupied low-altitude areas. Gehyra mutilata had the lowest abundance among all species at all altitudes. Diaoluo Mountain exhibited a higher species diversity and abundance than Jianfeng Ridge. Geckos on Diaoluo Mountain were mainly distributed between 31 and 920 m a.s.l., presenting a bimodal distribution, with peaks appearing in altitudinal zones II (181–330 m a.s.l.) and VI (781–930 m a.s.l.). The gecko distribution on Jianfeng Ridge ranged from 31 to 948 m a.s.l., presenting a unimodal distribution, with a peak in altitudinal zone V (631–780 m a.s.l.). Full article

An examination of 360 feral cats originating from three major habitats in the Dubai Emirate between 2002 and 2024 revealed the presence of 14 helminths, as follows: Joyeuxiella pasqualei, Joyeuxiella gervaisi, Diplopylidium nölleri, Diplopylidium acanthotetra, Hydatigera taeniaeformis, Taenia hydatigena, Ancylostoma braziliense, Ancylostoma ceylanicum, Ollulanus tricuspis, Toxocara cati, Toxascaris leonina, Pterygodermatites cahirensis, Centrorhynchus aluconis and Macracanthorhynchus catulinus. During the same period, a total of 66 snakes (eight species) and 68 lizards (four species) from different locations in the Dubai Emirate were examined for parasites. The larval stages of the cestode genera Joyeuxiella and Diplopylidium, as well as cystacanths of Centrorhynchus sp. and Macracanthorhynchus sp. and the larval stages of two nematodes were detected. All of the snake species except sand boas, as well as two gecko species, harbored the larval stages of cestodes of the Dipylidiidae family. The high prevalence of Joyeuxiella and Diplopylidium in the cats that originated from the city center of Dubai, where the presence of reptiles can be excluded, suggests that certain arthropods might be involved in the life cycle of these cestodes as first intermediate hosts and that reptiles are paratenic hosts. Full article

Boa constrictor snakes represent a suitable model for studying the absorption, metabolism, and elimination of tramadol due to their distinct physiological characteristics. The objective of this work was to provide preliminary data on the pharmacokinetics of tramadol and its active metabolite, O-desmethyltramadol (M1), in the plasma of Boa constrictor using liquid chromatography with fluorescence detection. Ten snakes received tramadol (5 mg kg⁻¹) both into the epaxial musculature (TRIM) and into the paravertebral vein (TRIV) with a 45-day interval between the two administration methods. Blood samples were taken at specified time points to analyze the pharmacokinetics. Data were evaluated with an independent pharmacokinetic model (R software version 4.3.0). A paired Student’s t-test was used for all parametric variables, except clearance, which was analyzed with the Wilcoxon test. A significance level of 5% was applied. The mean (range) maximum concentration of tramadol, volume of distribution, clearance, and elimination half-life for the TRIM group were 2.58 µg mL⁻¹, 10.58 ± 2.91 L kg⁻¹, 0.36 L kg⁻¹ h⁻¹, and 19.96 ± 8.34 h, respectively. For the TRIV group, these values were 3.39 µg mL⁻¹, 5.60 ± 1.69 L kg⁻¹, 0.22 L kg h⁻¹, and 17.32 ± 7.55 h⁻¹, respectively. M1 achieved maximum concentration and elimination half-lives of 0.58 µg mL⁻¹ and 49.89 ± 10.8 h, respectively, for TRIM and 0.59 µg mL⁻¹ and 35.66 ± 10.85 h for TRIV. The bioavailability of intramuscular tramadol was 61%, and M1 remained at similar concentrations for 20 min after tramadol administration in both treatments. Tramadol is rapidly biotransformed into M1 in Boa constrictors, maintaining high concentrations over an extended period. The pharmacokinetic characteristics, particularly the sustained plasma concentrations of M1, suggest potential for effective analgesia in the Boa constrictor. Furthermore, the intramuscular route provides the additional advantage of ease and practicality of administration. Full article

Mediterranean ecosystems have been grazed by livestock for thousands of years. While considered both a major anthropogenic stressor and a potential habitat conservation tool, the effects of livestock grazing on vertebrate populations remain poorly understood. Our study focused on goat and sheep grazing on a large island off the coast of Greece in order to shed light on (1) the nature of the relationship between livestock grazing and vertebrate assemblages, and (2) the mediating mechanisms. Sampling small mammal, reptile, and passerine bird species across a range of livestock grazing intensities in a Mediterranean pastoral system, we used Generalized Linear Modeling to test for the presence of a unimodal relationship between grazing disturbance and vertebrate diversity in line with the Intermediate Disturbance Hypothesis (IDH). An information-theoretic approach helped elucidate which habitat characteristics best predicted vertebrate-grazing responses. Terrestrial species abundance decreased steadily with increasing grazing, while species richness exhibited a unimodal response, peaking at intermediate livestock stocking rates and offering support for the IDH. This response was best predicted by invertebrate food availability. Both passerine bird species’ richness and abundance showed no clear relationship with grazing yet were significantly correlated with changes in vegetation structure. Our findings suggest that there is no ideal grazing level for broadly optimizing both vertebrate abundance and richness. However, only light-to-intermediate livestock stocking rates are associated with healthy wildlife populations while also promoting terrestrial species richness. Agricultural policy that avoids overgrazing while encouraging a mosaic of different grazing intensities at the regional level is needed to best support diverse vertebrate assemblages. Full article

The genus Blanus (Amphisbaenia: Blanidae) comprises fossorial, limbless reptiles with cryptic external morphology, making species delimitation particularly challenging. This study presents a comprehensive comparative osteological and geometric morphometric investigation of three Blanus species distributed in Türkiye—B. alexandri, B. aporus, and B. strauchi. Using both dry and cleared-and-stained specimens, diagnostic variations in cranial and postcranial skeletal elements, especially elements within the nasal, maxilla, vomer, squamosal, dentary, and coronoid bones, as well as vertebral counts were identified. A geometric morphometric analysis of the dorsal and ventral cranial morphology revealed distinct shape differences, particularly separating B. alexandri from the other two species along principal component axes. A phylogenetic analysis based on 45 discrete osteological characters supported the monophyly of the eastern Blanus clade, with B. alexandri forming a distinct lineage from B. aporus and B. strauchi. These findings emphasize the significance of skeletal morphology for resolving phylogenetic relationships and highlight the role of osteological characters in refining species boundaries within cryptic reptilian taxa. The integrative approach employed here underscores the evolutionary distinctiveness of Anatolian Blanus and enhances our understanding of morphological evolution in amphisbaenians. Full article

Many vertebrates have evolved resistance to snake venom as a result of coevolutionary chemical arms races. In Australian skinks (family Scincidae), who often encounter venomous elapid snakes, the frequency, diversity, and molecular basis of venom resistance have been unexplored. This study investigated the evolution of neurotoxin resistance in Australian skinks, focusing on mutations in the muscle nicotinic acetylcholine receptor (nAChR) α1 subunit’s orthosteric site that prevent pathophysiological binding by α-neurotoxins. We sampled a broad taxonomic range of Australian skinks and sequenced the nAChR α1 subunit gene. Key resistance-conferring mutations at the toxin-binding site (N-glycosylation motifs, proline substitutions, arginine insertions, changes in the electrochemical state of the receptor, and novel cysteines) were identified and mapped onto the skink organismal phylogeny. Comparisons with other venom-resistant taxa (amphibians, mammals, and reptiles) were performed, and structural modelling and binding assays were used to evaluate the impact of these mutations. Multiple independent origins of α-neurotoxin resistance were found across diverse skink lineages. Thirteen lineages evolved at least one resistance motif and twelve additional motifs evolved within these lineages, for a total of twenty-five times of α-neurotoxic venoms resistance. These changes sterically or electrostatically inhibit neurotoxin binding. Convergent mutations at the orthosteric site include the introduction of N-linked glycosylation sites previously known from animals as diverse as cobras and mongooses. However, an arginine (R) substitution at position 187 was also shown to have evolved on multiple occasions in Australian skinks, a modification previously shown to be responsible for the Honey Badger’s iconic resistance to cobra venom. Functional testing confirmed this mode of resistance in skinks. Our findings reveal that venom resistance has evolved extensively and convergently in Australian skinks through repeated molecular adaptations of the nAChR in response to the enormous selection pressure exerted by elapid snakes subsequent to their arrival and continent-wide dispersal in Australia. These toxicological findings highlight a remarkable example of convergent evolution across vertebrates and provide insight into the adaptive significance of toxin resistance in snake–lizard ecological interactions. Full article

Small rodents are known hosts of various pathogens, including Hepatozoon, but until now, in Brazil, only Hepatozoon milleri has been described in these animals. In this study, liver samples and blood smears were obtained from 289 rodents belonging to 14 Cricetidae and two Muridae species that had been captured in municipalities of the states of Paraná and Rio de Janeiro. Smears were stained with Giemsa, and gametocytes were detected via microscopy in 10.72% (n = 31/289) of samples, with these individuals representing three rodent species. Significant morphometric differences were observed in gametocyte measurements in Akodon rodents. Using conventional PCR, Hepatozoon spp. 18S rDNA fragments were amplified in 24.91% (n = 72/289) of samples, with those individuals representing seven rodent species. Phylogenetic analyses clustered 41 sequences from this study into a subclade with other sequences from small mammals in Brazil, identifying four distinct haplotypes, and, for the first time, a relationship between Hepatozoon haplotype and gametocyte length was observed. Based on phylogenetic analysis, this study reinforces the trophic relationship between rodents and reptiles as a possible link in the Hepatozoon transmission cycle in South America. Furthermore, our findings expand knowledge on Hepatozoon spp. hosts, describing Oxymycterus nasutus and Oxymycterus quaestor as new host species and identifying two novel circulating haplotypes in rodents from Paraná State, southern Brazil. Full article

Metarhizium (M.) granulomatis and M. viride have previously been described as pathogens causing hyalohyphomycosis in various species of captive chameleons and bearded dragons (Pogona vitticeps). Previous studies yielded different genotypes of M. granulomatis and M. viride based on sequencing of the internal transcribed spacer 1-5.8S rDNA (ITS-1-5.8S) and a fragment of the large subunit of the 28S rDNA (LSU). The aim of this study was to clarify the relationships between these genotypes and obtain a more accurate phylogenetic classification by sequencing two different loci of the RNA polymerase II second largest subunit (NRPB2), referred to as RPB1 and RPB2, and the translation elongation factor 1 alpha (EF1α). A total of 23 frozen isolates from 21 lizards, including the first isolates of M. granulomatis and M. viride from Parson’s chameleons (Calumma parsonii), were available for phylogenetic analysis. A total of 13 isolates belonged to the M. granulomatis complex and 10 isolates belonged to the M. viride complex. Following the amplification and sequencing of the protein-coding genes, the resulting nucleotide sequences were analyzed, trimmed and assembled. These were further analyzed with regard to differences in single-nucleotide polymorphisms (SNPs) and amino acid structure. In consideration of the results of the present analyses, a phylogenetic reclassification is recommended. Three different genotypes of M. granulomatis can be distinguished, which can be phylogenetically addressed as subspecies. Six subspecies can be distinguished regarding M. viride. Full article

Influenza A virus (IAV) poses a significant threat to animal and public health due to its wide host range and potential for interspecies transmission. This study aimed to conduct a comprehensive survey of IAV in a wide range of wildlife in the Orinoco flooded savannas of Colombia, a region of high biodiversity and a strategic location for monitoring viral transmission. Sampling was conducted during both dry and rainy seasons in two localities. ELISA and qPCR targeted 2028 individuals from 173 bird, mammal, and reptile species, 124 of them without previously published reports. There were positive results for 54 species, with 34 representing first-time world reports. Of the qPCR, 13.4% were positive from birds, and 2.9% were from mammals. Seropositivity was identified in 5.7% of birds, 2.7% of mammals, and 1.3% of reptiles. These findings underscore the potential role of these diverse species as reservoirs or incidental hosts in the transmission cycle of IAV, emphasizing the need for expanded research on less-studied taxa and their ecological interactions. The results also contribute to our understanding of the epidemiology of IAV in the Neotropics and can inform future surveillance and mitigation strategies. Full article

Mycoplasmas are known respiratory pathogens in tortoises, but few studies exist in snakes. To better understand the correlation with clinical signs and co-infections, samples from mycoplasma-positive snakes with and without clinical respiratory disease were analyzed. Oral swabs from 15 snakes (pythons n = 12, boas n = 3) were examined using polymerase chain reaction (PCR) and third-generation sequencing (TGS). Additionally, mycoplasma isolation assays were performed. Pathogens detected by PCR included Mycoplasmas (15/15, 100%), serpentoviruses (9/15, 60%), and Chlamydia sp. (2/15, 13%); those detected by TGS included Mycoplasmas (14/15, 93%), serpentoviruses (10/15, 67%), Chlamydia sp. (1/15, 7%), and 15 different bacterial species. Sequencing of the mycoplasma PCR products revealed a close genetic relationship to Mycoplasmopsis agassizii. TGS identified genetically distinct mycoplasmas and three different serpentoviruses. While mycoplasmas could not be successfully propagated, Brucella intermedia comb. nov. was identified in eight cultures. Respiratory disease in snakes is often multifactorial, involving various pathogens and environmental influences. This study demonstrates that comprehensive diagnostics are essential for understanding disease processes in snakes and improving the detection of diverse pathogens. Further research is needed to improve laboratory diagnostics for infectious diseases in reptiles and to better understand the roles of various pathogens in respiratory diseases in snakes. Full article

In farmed animals, body color is not only an ecological trait but also an important trait that influences the commercial value of the animals. Melanin plays an important role in the formation of body color in animals, while the tyrosinase (TYR) gene family is a group of key enzymes that regulate melanogenesis. The Chinese soft-shelled turtle (Pelodiscus sinensis) is one of the most important reptiles in freshwater aquaculture. However, the potential role of the TYR gene family in the body color formation of P. sinensis remains unclear. This study aimed to investigate the expression and conservation of the TYR gene family in relation to body color variation in P. sinensis. Three core members of this gene family were identified from the P. sinensis genome. Following identification, the genomic features were analyzed. They shared similar physicochemical properties and conserved domains. Chromosome mapping showed that the three genes of P. sinensis were all located on the autosomes, while phylogenetic and collinearity analysis suggested that the protein functions of the three genes in the studied species were highly conserved. Amino acid sequence alignment indicated high conservation among the three TYR gene family proteins (TYR, TYRP1, and DCT) in multiple critical regions, particularly in their hydrophobic N-/C-terminal regions and cysteine/histidine-rich conserved domains. The qRT-PCR revealed that the TYR and DCT genes were highly expressed in the eyes of individuals with different body colors. The expression levels of TYR and TYRP1 genes in the skin were significantly higher in dark-colored individuals than in light-colored ones (p < 0.05). These results will lay the groundwork for functional studies and breeding programs targeting color traits in aquaculture. Full article