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Objective: The aim of this study was to document ophthalmic examination findings and provide reference values for ocular examinations and diagnostics in clinically normal Western tiger salamanders (Ambystoma mavortium) and to evaluate the mydriatic effect of a topical rocuronium bromide and identify any adverse effects., Animals Studied: Sixteen Western tiger salamanders., Procedure: A complete ophthalmic examination, including intraocular pressure via rebound tonometry [iCare® TonoVet (dog-setting) or iCare® TonoVet Plus (dog-setting)], and fluorescein and Rose Bengal stains, was performed. Ocular surface flora culture swabs were collected for microbiology in four salamanders. Rocuronium bromide (50 μL; 0.01 mg) was administered into each eye in three salamanders. Pupil size and constriction ability were evaluated up to 60 min following administration of rocuronium bromide. Distant visual examination and Doppler heart rate were used to monitor for potential adverse effects of rocuronium bromide., Results: Observed ocular abnormalities included lipid keratopathy/keratitis (19%; 3/16), parasitic ophthalmitis (19%; 3/16), and cataracts (6.3%; 1/16). A significant difference was found between tonometry with iCare® TonoVet (11.5 ± 2.7 mmHg) versus TonoVet Plus (15.4 ± 3.7 mmHg) (p = .025). Fluorescein and Rose Bengal stains were negative in all salamanders. Ocular surface microbiology revealed a high incidence of contamination from environmental flora, with the most common isolate being unidentified as Gram-negative nonfermenters (75%; 3/4). No significant change in pupil size or constriction ability was observed with rocuronium bromide., Conclusion: This is the first study to document ocular examination findings and diagnostics in captive and wild urodeles and may serve as a reference for clinical assessment and future studies of the Western tiger salamander., (© 2024 The Authors. Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.)

The objective of this study was to describe the intraocular pressure (IOP) findings in a population of Chinese edible frogs (Hoplobatrachus rugulosus) sold in wet markets across Hong Kong and to characterize the influence of sex and anesthesia. One hundred animals were evaluated, and 96 were included in this study. All frogs included appeared ophthalmologically normal upon gross examination. Intraocular pressure was evaluated with rebound tonometry (TonoVet Plus® setting "d") on conscious frogs and under anesthesia. General anesthesia was induced with MS-222 (tricaine methanesulfonate) 2 g/L by immersion. After IOP measurements, the frogs were euthanized with intravenous pentobarbital (200 mg/ml) and sex was confirmed on postmortem examination. Mean (± SD) IOP values were significantly decreased under MS-222 anesthesia in males (14.7 ± 2.8 mmHg; P < 0.0001) and females (14.7 ± 2.4 mmHg; P < 0.0001) compared to conscious readings (16.3 ± 2.1 mmHg and 16.3 ± 2.1 mmHg, respectively). There was no significant difference in IOP found between males and females before or after anesthesia. There was no significant difference between the right and left eye in males and females before or after anesthesia. The results of this study establish a normal range of IOP for this species and are comparable to previous published reports of IOP in anurans. [ABSTRACT FROM AUTHOR]

Louisiana pine snakes (Pituophis ruthveni) are a threatened species with a range limited to portions of Louisiana and Texas. There are captive reproduction programs that aim to assist in the recovery of this species. Therefore, obtaining information that can aid in maintaining their health, such as a complete ocular examination, is a critical component in conservation efforts. Examination of the snake ocular posterior segment is challenging because of the presence of striated uveal musculature that is unresponsive to anticholinergic agents, and the presence of the spectacle, which may create a barrier to topical mydriatics. The objectives of this study were to document normal ocular biometric measurements (axial globe length [AP], lens thickness (LT), and vitreous chamber depth [VCD]) in this species using ultrasonography (US) and to assess the effects of topically applied rocuronium bromide (RB) solution (one- and two-drop protocol, 20 μl and 40 μl, respectively) to facilitate noninvasive examination of the fundus. The ocular biometric measurements were then correlated to morphometric data including snout–vent length (SVL), tail length (TL), total body length (SVL + TL), sex, and body condition score (BCS). We found that US, using an 8–18-MHz linear array probe, provided adequate image quality to measure the above parameters in all snakes (n = 8), and that there were no significant correlations between the morphometric data and ocular biometric US measurements (P > 0.05). RB solution applied topically to the healthy, intact spectacle did not induce mydriasis in a subset of this same population (n = 6; P > 0.05) using either the one- or two-drop protocol. In conclusion, ocular US can be utilized as a noninvasive diagnostic tool in Louisiana pine snakes and further studies are needed to evaluate noninvasive methods of inducing mydriasis in this species. [ABSTRACT FROM AUTHOR]

Objectives: To describe the etiology, clinical pathology, and treatment of subspectacular abscesses (SAs) in 16 snakes., Animals Studied: Sixteen snakes from private captive collections that were presented at a veterinary teaching hospital and diagnosed with SAs., Procedures: Exudate was collected from SAs via percutaneous aspiration or by performing a partial spectaculectomy and submitted to direct light microscopic examination and/or microbiological examination., Results: Bacterial isolates were cultured from exudate samples in 12 out of 16 snakes and comprised Pseudomonas aeruginosa isolates that showed identical antimicrobial susceptibility patterns in seven cases. Direct light microscopic examination demonstrated the presence of flagellated protozoa in the exudate in 10 out of 16 snakes and in all of these snakes, concurrent oropharyngeal flagellated protozoan infection could be demonstrated. Combined flagellated protozoan and bacterial SA infection was demonstrated in six snakes. Comparison of small subunit ribosomal RNA gene sequences of flagellated protozoans that were detected in the exudate of SAs from four snakes revealed they represented the parabasalians Monocercomonas colubrorum and Hypotrichomonas acosta in one and three cases, respectively. In all snakes, successful treatment of the SAs was achieved following surgical debridement of the subspectacular space combined with antimicrobial treatment., Conclusion: Bacteria as well as flagellates are considered to reach the subspectacular space through ascending infection from the oral cavity via the lacrimal duct. Although opportunistic bacterial infection presumably constitutes the predominant cause of SAs in snakes, the role of flagellate infection in the pathogenesis of this disorder should be further elucidated., (© 2024 American College of Veterinary Ophthalmologists.)

Consider the Plücker embedding of the Grassmannian of three dimensional subspaces of a seven dimensional space, G 3 , 7 , in projective space P (⋀ 3 C 7) . The maximal torus of diagonal matrices in S L (7 , C) acts on G 3 , 7 and so it is natural to seek geometric properties of the GIT quotient of G 3 , 7 with respect to this action. Using the notation L (ω 3) for the line bundle on G 3 , 7 coming from its Plücker embedding, it is known that the twisted line bundle L (7 ω 3) descends to the GIT quotient. We show that the GIT quotient is projectively normal for this polarization. We compute the generators of the ring of torus invariants by computing the Hilbert basis of certain polyhedral cones. In this paper, we also begin a study of the torus quotients of S L (5 , C) / Q , when Q is the intersection of two maximal parabolic subgroups in S L (5 , C) containing a Borel subgroup. We describe the GIT quotient explicitly in some cases and prove geometric properties of the embedding of the quotient when the line bundle descends to it. [ABSTRACT FROM AUTHOR]

Panamanian golden frog (PGF) ( Atelopus zeteki ) is a critically endangered species. The Maryland Zoo in Baltimore houses two groups of PGF originating from distinct geographic locations as an assurance colony, with the goal of upholding genetics for future release of individuals back to their native environment. The purpose of this cross-sectional study was to characterize the prevalence of ocular abnormalities in these two zoo-housed populations of PGF as well as to establish normal parameters for selected diagnostic tests in these groups. Twenty-five females and 25 males were randomly selected from each group (100 PGF; 200 eyes in total) to undergo ocular examination using slit lamp biomicroscopy and direct ophthalmoscopy. Endodontic absorbent paper point test (EAPPT) and intraocular pressure (IOP) and Rose Bengal stain diagnostic tests were also performed. Reference ranges for tear production (EAPPT, 0.5-3 mm/min) and IOP (14-26 mmHg) were calculated in the nondiseased PGF eyes ( n = 160 eyes). Rose Bengal stain uptake was negative on all eyes. In total, 40 eyes of 30 PGF were found to have some form of ocular abnormality (28% of PGF, 20% of eyes). The most frequently observed ocular abnormalities were cataract (9% of PGF, 6% of eyes) and keratitis (nonlipid keratopathy; 10% of PGF, 5.5% of eyes). There was no significant difference in overall ocular abnormality prevalence between the two groups studied ( P = 0.37) or between the sexes ( P = 0.76). The median age of an eye with cataract and keratitis (nonlipid keratopathy) was 10.35 and 7.7 yr, respectively. Ocular abnormalities are common in these two populations of PGF. Documentation of these ocular abnormalities and establishment of diagnostic reference ranges have not previously been published and may be important for maintaining the health of this endangered species.

Ranaviruses have been detected in over 12 families of reptiles including many genera of turtles, tortoises, and terrapins, but the pathogenesis of these infections is still poorly understood. Krefft's river turtle hatchlings (N = 36; Emydura macquarii krefftii) were inoculated intramuscularly with Bohle iridovirus (BIV, Ranavirus, isolate) or saline, and euthanized at 9 timepoints (3 infected and 1 control per timepoint) over a 24-day period. Samples of lung, liver, kidney, and spleen were collected for quantitative polymerase chain reaction (PCR); internal organs, skin, and oral cavity samples were fixed for histopathological examination. The earliest lesions, at 8 days postinoculation (dpi), were lymphocytic inflammation of the skin and fibrinoid necrosis of regional vessels at the site of inoculation, and mild ulcerative necrosis with lymphocytic and heterophilic inflammation in the oral, nasal, and tongue mucosae. Fibrinonecrotic foci with heterophilic inflammation were detected in spleen and gonads at 16 dpi. Multifocal hepatic necrosis, heterophilic inflammation, and occasional basophilic intracytoplasmic inclusion bodies were observed at 20 dpi, along with ulcerative lymphocytic and heterophilic tracheitis and bronchitis. Tracheitis, bronchitis, and rare bone marrow necrosis were present at 24 dpi. Of the viscera tested for ranaviral DNA by PCR, the liver and spleen had the highest viral loads throughout infection, and thus appeared to be major targets of viral replication. Testing of whole blood by qPCR was the most-effective ante-mortem method for detecting ranaviral infection compared with oral swabs. This study represents the first time-dependent pathogenesis study of a ranaviral infection in turtles. [ABSTRACT FROM AUTHOR]

Herpesviruses are found in free-living and captive chelonian populations, often in association with morbidity and mortality. To date, all known chelonian herpesviruses fall within the subfamily Alphaherpesvirinae. We detected a novel herpesvirus in 3 species of chelonians: a captive leopard tortoise (Stigmochelys pardalis) in western TX, USA; a steppe tortoise (Testudo [ Agrionemys ] horsfieldii) found near Fort Irwin, CA, USA; and 2 free-living, three-toed box turtles (Terrapene mexicana triunguis) found in Forest Park, St. Louis, MO. The leopard tortoise was coinfected with the tortoise intranuclear coccidian and had clinical signs of upper respiratory tract disease. The steppe tortoise had mucopurulent nasal discharge and lethargy. One of the three-toed box turtles had no clinical signs; the other was found dead with signs of trauma after being observed with blepharedema, tympanic membrane swelling, cervical edema, and other clinical signs several weeks prior to death. Generally, the branching order of the turtle herpesviruses mirrors the divergence patterns of their hosts, consistent with codivergence. Based on phylogenetic analysis, this novel herpesvirus clusters with a clade of viruses that infect emydid hosts and is likely of box turtle origin. Therefore, we suggest the name terrapene alphaherpesvirus 3 (TerAHV3) for the novel virus. This virus also has the ability to host-jump to tortoises, and previously documented herpesviral morbidity tends to be more common in aberrant hosts. The relationship between clinical signs and infection with TerAHV3 in these animals is unclear, and further investigation is merited. [ABSTRACT FROM AUTHOR]

Over a 3.5-year period, tissue samples from 141 companion and aviary birds with clinically suspected, naturally occurring solid neoplasms were collected via surgical biopsy (n = 53) or at necropsy examination (n = 88) from a population of birds presenting to an avian veterinary clinic in Melbourne, Australia. Neoplastic processes were identified in 73.7% (n = 104) of samples, with 83.7% (n = 87) being interpreted as malignant neoplasia and 16.3% (n = 17) being interpreted as benign neoplasia. The overall estimated prevalence of neoplasia in the study population (n = 5125) was 2.45% (95% confidence interval, 2-2.97%). The gastrointestinal and reproductive tracts were the most commonly affected systems. The most common presenting signs were nonspecific and included lethargy, coelomic distension, and inappetence. In 59 cases, fine-needle aspirates (FNAs) and impression smears were also obtained and evaluated cytologically. The accuracy of cytology for detecting neoplasia in birds and for determining whether a neoplastic process was benign or malignant was assessed by using histopathology as the "gold standard." There was complete agreement between the cytological and histopathological diagnoses in 72.8% (43/59) of cases. Cytology correctly identified 87.5% of these cases (35/40) as malignant neoplasms and 55.6% (5/9) as benign processes. There was no significant difference between the use of cytology and histopathology for the detection of malignant neoplasia in birds ( P = 0.185). The accuracies of FNAs and impression smears for examining avian tumors were also compared. Overall, the best cell preservation was obtained by performing impression smears from tissues, with 62.2% (n = 28) returning high cellularity for cytological examination, compared to 53.8% (n = 14) when samples were obtained by FNA. This study provides an overview of the types and prevalence of neoplasms in a captive bird population from Australia, correlates physical examination findings with tumor types, and provides evidence that cytology is a reliable preliminary diagnostic tool for detecting neoplasia in birds.

A 32-year-old male salmon-crested cockatoo ( Cacatua moluccensis ) was diagnosed by cytology with bilateral cubital lymphoma and mycobacteriosis. Polymerase chain reaction assay testing confirmed Mycobacterium genavense . This patient was subsequently humanely euthanized. Postmortem histopathology confirmed both diagnoses with findings of multicentric lymphoma, acid-fast bacilli, and severe degenerative changes in all synovial joints examined. Immunohistochemical staining for paired box protein 5 of the cubital mass was positive for a high percentage of B-cell lymphocytes, consistent with B-cell lymphoma. This unusual case of two major diseases presenting concurrently in one patient raises the question of whether the pathogenesis could have an interdependent relationship. Mycobacteriosis, severe degenerative joint changes, or both may have stimulated lymphocytes, eventually leading to lymphoma. Additional screening and monitoring for comorbidities may be advised if 1 of these diseases are diagnosed in companion avian species.

This paper is aimed at demonstrating that some geometrical and topological transformations and operations serve not only as promoters of many specific genetic and cellular events in multicellular living organisms, but also as initiators of the organization and regulation of their functions. Thus, changes in the form and structure of macromolecular and cellular systems must be directly associated to their functions. There are specific classes of enzymes that manipulate the geometry and topology of complex DNA-protein structures, and thereby they perform many important cellular processes, including segregation of daughter chromosomes, gene regulation, and DNA repair. We argue that form has an organizing power, hence a causal action, in the sense that it enables to induce functional events during different biological processes, at the supramolecular, cellular, and organismal levels of organization. Clearly, topological forms must be matched with specific kinetic and dynamical parameters to have a functional effectiveness in living systems. This effectiveness is remarkably apparent, to give an example, in the regulation of the genome functions and in cell activity. In more general terms, we try to show that the conformational plasticity of biological systems depends on different kinds of topological manipulations performed by specific families of enzymes. In doing so, they catalyze all those spatial and dynamical changes of biological structures that are suitable for the functions to be acted by the organism., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)