Heart place and tail length evaluation in Naja oxiana, Macrovipera lebetina, and Montivipera latifii

Morphometric characteristics and seasonal proximity to water of the Cypriot blunt-nosed viper Macrovipera lebetina lebetina (Linnaeus, 1758)

BACKGROUND

The blunt-nosed viper Macrovipera lebetina (Linnaeus, 1758) is a medically important snake species in the Middle East. Its nominate subspecies Macrovipera l. lebetina is confined to Cyprus, where it is the only dangerously venomous snake species and heavily pursued. Despite the viper's large size, data on its body mass and sex-specific morphological differences are scarce. It is commonly believed that M. l. lebetina prefers freshwater proximity during summer. Hence, we aimed at investigating M. l. lebetina sex-specific morphological differences and its possible attraction to freshwater bodies in late summer.

METHODS

Morphometric characteristics, proximity to water and conservation status of M. l. lebetina were investigated in Paphos district (Cyprus) in 2014, 2015 and 2017. Vipers were caught in different habitats, examined morphologically for metric and meristic characters, and released back into their habitat. Additionally, local people were interviewed about the conservation situation of the species.

RESULTS

Of 38 recorded blunt-nosed vipers, morphological characteristics were collected from 34 (10 adult males, 16 adult females, eight unsexed juveniles). Rounded total length (ToL) ranged from 23.5 cm to 133.0 cm and weight between 10 g and 1456 g. Adult males significantly exceeded adult females in tail length (TaL), ToL and head length (HL). No significant sex-specific differences were found in snout-vent length (SVL), head width (HW), weight or body condition index (BCI), nor for the ratios TaL / SVL, TaL / ToL, HL / SVL or HL / HW. Adult females from late summer (2015) had a significantly lower mean BCI than those from spring (2014).Distances of blunt-nosed vipers to the nearest water bodies (natural and artificial, respectively) did not differ significantly between spring (2014) and late summer (2015). There was also no significant difference between the distances of vipers to natural and to artificial water bodies in spring (and late summer).

CONCLUSIONS

Adult male blunt-nosed vipers exceed adult females in TaL, ToL and HL. Adult females are likely in a more vulnerable body condition in late summer than in spring. Periodic drying out of freshwater bodies in summer probably does not affect the species' occurrence. Educational workshops and habitat conservation are recommended for reducing human-viper conflict.

Differential growth of body segments explains ontogenetic shifts in organ position for the Diamondback Water Snake (Nerodia rhombifer)

As snakes grow, their organs move anteriorly relative to body size. We explored a developmental explanation for the ontogenetic shift in the relative position of internal organs for snakes using the Diamondback Water Snake (Nerodia rhombifer (Hallowell, 1852)). With age, this water snake’s heart, liver, small intestine, and right kidney move anteriorly by 2.5–5.0 percentage points of snout–vent length. The number of precaudal vertebrae did not vary due to size or sex. The anterior edge of the heart, liver, small intestine, and right kidney were typically aligned within a span of 4–8 vertebrae that likewise did not differ as a function of size or sex. Snakes exhibited a positive relationship between the number of precaudal vertebrae and the vertebra number aligned with each organ. Total length, centrum length, centrum width, ball width, height, and mass of eight vertebrae sampled at consistent vertebral number revealed that vertebrae in the middle region of the body grow at a greater rate than vertebrae at the anterior or distal ends of the body. For N. rhombifer, the observed forward shift in relative organ positions is the product of regional differences in the growth of body segments. Predictably, these differences arise from a developmental program generated by the differential expression of Hox genes.

Clinicopathologic characterization of visceral gout of various internal organs--a study of 2 cases from a venom and toxin research center

BACKGROUND

Gout is a metabolic disorder that results in hyperuricemia and the deposition of positively birefringent monosodium urate crystals in various parts of the body. The purpose of this study was to characterize the incidence and diagnostic features of visceral gout found at necropsy in two patients.

CASE PRESENTATION

The authors present an unusual report of untreated gout leading to major structure destructions in visceral organs. Gross post-mortem examination revealed a white powdery substance and display needle-like crystalline symmetry under the macroscopic on the visceral surfaces. Microscopically, the presence of crystalline deposits (urate tophi) were detected in visceral organs, such as; kidney, liver, lung and mesentery. Irrespective of its location, gout was observed, by H&E, as intracellular and extracellular eosinophilic deposits that compressed surrounding tissues. Moreover, numerous necrotizing granulomas of multifarious sizes were observed that were compounded by large aggregations of eosinophilic material (gout), surrounded by epithelioid macrophages, lymphoplasmacytic cells, foreign body multinucleated giant cells, fibrosis, fibroplasia and few edema. On the other hand, our results revealed that granulomatous nodules in the mesentery and kidney contained large numbers of gout foci compared with lung and liver. Furthermore, the immediate cause of death in these cases were not identified, but appeared to result from multiple factors, including the visceral gout due to unsuitable environmental conditions.

CONCLUSION

In summary, we have identified a valid histopathologic damage index for use in laboratory studies of visceral gout. This system provides a feasible method of representing visceral damage in gout, and may allow for better understanding of the natural history, pathophysiology and the management of acute attacks of gouty visceral in this disease. Finally, to the best of our knowledge, understanding of the distribution of monosodium urate crystals within the body can aid clinical diagnosis and further understanding of the resulting pathology.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1293547351151638 .