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The African rock python is a cosmopolitan snake in Nigeria widely kept as a zoo animal and also in recreational facilities. There is need for chemical immobilisation of this animal species for managemental, diagnostic and therapeutic procedures. A mixture of xylazine and ketamine (XK) was compared with the administration of a mixture of xylazine and normal saline solution (XS) in six captive African rock pythons in 2 trials with reference to onset and duration of anaesthesia. Changes in the heart rate (HR), respiratory rate (RR) and rectal temperature (RT) as well as selected biochemical parameters were recorded. Although there were no statistically significant (P>0.05) differences in HR and RR values between XK and XS treatments, significant (P

The African rock python is a cosmopolitan snake in Nigeria widely kept as a zoo animal and also in recreational facilities. There is need for chemical immobilisation of this animal species for managemental, diagnostic and therapeutic procedures. A mixture of xylazine and ketamine (XK) was compared with the administration of a mixture of xylazine and normal saline solution (XS) in six captive African rock pythons in 2 trials with reference to onset and duration of anaesthesia. Changes in the heart rate (HR), respiratory rate (RR) and rectal temperature (RT) as well as selected biochemical parameters were recorded. Although there were no statistically significant (P>0.05) differences in HR and RR values between XK and XS treatments, significant (P<0.05) differences were recorded for RT. Nonetheless, the significant differences were of no clinical importance. It was therefore recommended to safely immobilise an African rock python using XK for a procedure lasting over 1 hour with minimal cardiopulmonary and plasma enzymatic effect. To the knowledge of the authors, this is the first study assessing the anaesthetic efficacy and safety in African Rock pythons. [ABSTRACT FROM AUTHOR]

Abstract: Reproductive strategies such as parental care have been pivotal in evolutionary innovations such as endothermy in birds and mammals. The diversity of reproductive biology across the squamates provides a unique opportunity for elucidating the selective forces responsible for the evolution of various reproductive strategies. Here, I report on the reproductive biology of the southern African python (Python natalensis), based on a 7‐year study of free‐ranging pythons, revealing a behavioural complexity not usually expected for snakes. Mating occurred in the austral winter, with individual males following females for more than 2 months. As is typical for pythons, females brooded eggs by coiling around the clutch. Females are capital breeders; they lost ~40% body mass during a breeding event and did not breed in consecutive years. There was no evidence of the facultative thermogenesis that has been reported in congeners, suggesting that facultative thermogenesis has arisen independently more than once in Python. Reproductive females thermoregulated more carefully than non‐reproductives, maintaining higher, more stable Tbs at all stages of reproduction, especially while brooding. This was achieved by a stereotypic basking regime facilitated by ‘facultative melanism’, with females darkening significantly for the entire breeding event. Mothers remained with neonates at the nest site for approximately 2 weeks after hatching. During this time, mothers alternated between brief bouts of basking on the surface and coiling around the hatched eggs, on which the neonates rested. Neonates formed an aggregation near the burrow entrance to bask during the day, individually returning to the nest intermittently throughout the day. During the night, neonates remained within the mother's coils on the hatched eggs. This study highlights the diversity of reproductive biology within Python and cautions against generalization in this regard. This is the first unambiguous report of maternal care of neonates in an oviparous snake. [ABSTRACT FROM AUTHOR]

A total of 64 snakes (Reticulated python, Indian Rock Python, Rat snakes and Spectacled cobra) were examined for skin affections at Chennai Snake Park Trust (Guindy), Arignar Anna Zoological Park (Vandalur) and Rescue centre (Velachery) of Tamil Nadu from September, 2015 to June, 2016 and the, ndings were reported. [ABSTRACT FROM AUTHOR]

The ventricles of non-crocodilian reptiles are incompletely divided and provide an opportunity for mixing of oxygen-poor blood and oxygen-rich blood (intracardiac shunting). However, both cardiac morphology and in vivo shunting patterns exhibit considerable interspecific variation within reptiles. In the present study, we develop an in situ double-perfused heart approach to characterise the propensity and capacity for shunting in five reptile species: the turtle Trachemys scripta, the rock python Python sebae, the yellow anaconda Eunectes notaeus, the varanid lizard Varanus exanthematicus and the bearded dragon Pogona vitticeps. To simulate changes in vascular bed resistance, pulmonary and systemic afterloads were independently manipulated and changes in blood flow distribution amongst the central outflow tracts were monitored. As previously demonstrated in Burmese pythons, rock pythons and varanid lizards exhibited pronounced intraventricular flow separation. As pulmonary or systemic afterload was raised, flow in the respective circulation decreased. However, flow in the other circulation, where afterload was constant, remained stable. This correlates with the convergent evolution of intraventricular pressure separation and the large intraventricular muscular ridge, which compartmentalises the ventricle, in these species. Conversely, in the three other species, the pulmonary and systemic flows were strongly mutually dependent, such that the decrease in pulmonary flow in response to elevated pulmonary afterload resulted in redistribution of perfusate to the systemic circuit (and vice versa). Thus, in these species, the muscular ridge appeared labile and blood could readily transverse the intraventricular cava. We conclude that relatively minor structural differences between non-crocodilian reptiles result in the fundamental changes in cardiac function. Further, our study emphasises that functionally similar intracardiac flow separation evolved independently in lizards (varanids) and snakes (pythons) from an ancestor endowed with the capacity for large intracardiac shunts. [ABSTRACT FROM AUTHOR]

Cytotoxic and antitumour factors have been documented in the venom of snakes, although little information is available on the identification of cytotoxic products in snake serum. In the present study, we purified and characterized a new cytotoxic factor from serum of the non-venomous African rock python (Python sebae), endowed with antitumour activity. PSS (P. sebae serum) exerted a cytotoxic activity and reduced dose-dependently the viability of several different tumour cell lines. In a model of human squamous cell carcinoma xenograft (A431), subcutaneous injection of PSS in proximity of the tumour mass reduced the tumour volume by 20%. Fractionation of PSS by ion-exchange chromatography yielded an active protein fraction, F5, which significantly reduced tumour cell viability in vitro and, strikingly, tumour growth in vivo. F5 is composed of P1 (peak 1) and P2 subunits interacting in a 1:1 stoichiometric ratio to form a heterotetramer in equilibrium with a hexameric form, which retained biological activity only when assembled. The two peptides share sequence similarity with PIP {PLI-γ [type-γ PLA2 (phospholipase A2) inhibitor] from Python reticulatus}, existing as a homohexamer. More importantly, although PIP inhibits the hydrolytic activity of PLA2, the anti-PLA2 function of F5 is negligible. Using high-resolution MS, we covered 87 and 97% of the sequences of P1 and P2 respectively. In conclusion, in the present study we have identified and thoroughly characterized a novel protein displaying high sequence similarity to PLI-γ and possessing remarkable cytotoxic and antitumour effects that can be exploited for potential pharmacological applications. [ABSTRACT FROM AUTHOR]

Abstract: This study explores the microscopic craniofacial morphogenesis of the oviparous African rock python (Python sebae) spanning the first two-thirds of the post-oviposition period. At the time of laying, the python embryo consists of largely undifferentiated mesenchyme and epithelium with the exception of the cranial base and trabeculae cranii, which are undergoing chondrogenesis. The facial prominences are well defined and are at a late stage, close to the time when lip fusion begins. Later (11–12d), specializations in the epithelia begin to differentiate (vomeronasal and olfactory epithelia, teeth). Dental development in snakes is different from that of mammals in several aspects including an extended dental lamina with the capacity to form 4 sets of generational teeth. In addition, the ophidian olfactory system is very different from the mammalian. There is a large vomeronasal organ, a nasal cavity proper and an extraconchal space. All of these areas are lined with a greatly expanded olfactory epithelium. Intramembranous bone differentiation is taking place at stage 3 with some bones already ossifying whereas most are only represented as mesenchymal condensations. In addition to routine histological staining, PCNA immunohistochemistry reveals relatively higher levels of proliferation in the extending dental laminae, in osseous mesenchymal condensations and in the olfactory epithelia. Areas undergoing apoptosis were noted in the enamel organs of the teeth and osseous mesenchymal condensations. We propose that localized apoptosis helps to divide a single condensation into multiple ossification centres and this is a mechanism whereby novel morphology can be selected in response to evolutionary pressures. Several additional differences in head morphology between snakes and other amniotes were noted including a palatal groove separating the inner and outer row of teeth in the upper jaw, a tracheal opening within the tongue and a pharyngeal adhesion that closes off the pharynx from the oral cavity between stages 1 and 4. Our studies on these and other differences in the python will provide valuable insights into in developmental, molecular and evolutionary mechanisms of patterning. [Copyright &y& Elsevier]

Abstract: This study explores the post-ovipositional craniofacial development of the African Rock Python (Python sebae). We first describe a staging system based on external characteristics and next use whole-mount skeletal staining supplemented with Computed tomography (CT) scanning to examine skeletal development. Our results show that python embryos are in early stages of organogenesis at the time of laying, with separate facial prominences and pharyngeal clefts still visible. Limb buds are also visible. By 11 days (stage 3), the chondrocranium is nearly fully formed; however, few intramembranous bones can be detected. One week later (stage 4), many of the intramembranous upper and lower jaw bones are visible but the calvaria are not present. Skeletal elements in the limbs also begin to form. Between stages 4 (day 18) and 7 (day 44), the complete set of intramembranous bones in the jaws and calvaria develops. Hindlimb development does not progress beyond stage 6 (33 days) and remains rudimentary throughout adult life. In contrast to other reptiles, there are two rows of teeth in the upper jaw. The outer tooth row is attached to the maxillary and premaxillary bones, whereas the inner row is attached to the pterygoid and palatine bones. Erupted teeth can be seen in whole-mount stage 10 specimens and are present in an unerupted, mineralized state at stage 7. Micro-CT analysis reveals that all the young membranous bones can be recognized even out of the context of the skull. These data demonstrate intrinsic patterning of the intramembranous bones, even though they form without a cartilaginous template. In addition, intramembranous bone morphology is established prior to muscle function, which can influence bone shape through differential force application. After careful staging, we conclude that python skeletal development occurs slowly enough to observe in good detail the early stages of craniofacial skeletogenesis. Thus, reptilian animal models will offer unique opportunities for understanding the early influences that contribute to perinatal bone shape. [Copyright &y& Elsevier]

The object of this study was to report a post mortem findings of a female Indian Rock Python with a length of 406 cm (13.32 feet) and approximate weight of 60 kg (including a whole deer that was swallowed by the python), that was brought to the Teaching Veterinary Hospital, Chittagong Veterinary and Animal Sciences University (CVASU) by the Forest Department of Kumira Range Office, Chittagong. The local inhabitants accidently found the python at the forest area of Kumira and they frightenedly injured and killed the snake eventually. The postmortem (PM) examination was performed according to standard protocols. Gross examination revealed bloody discharge was come out through mouth and a couple of skin lacerations observed on the right dorso-lateral part of the abdominal region. The whole barrel-shaped body cavity was opened and whole deer (partially decomposed) was recovered from the stomach. Furthermore, three fractured ribs were found on right thorax. The PM examination team believes that the possible cause of python death was traumatic injury inflicted by the local people. [ABSTRACT FROM AUTHOR]

Hematology and plasma biochemistry parameters are useful in the assessment and management of threatened and endangered species. Although reference values are readily available for many mammalian species, reference values for snakes are lacking for most species. We determined hematology and plasma biochemistry values for captive African rock pythons ( Python sebae ) and studied the effects of age, sex, season and hemoparasites on these values. Blood (5 mL) was collected by venipuncture of ventral coccygeal vein from 19 African rock pythons in rainy season and 14 snakes from the same population in dry season. There was no significant statistical difference ( P  < .05) between males and females to any of the parameters measured except total calcium in the rainy season. Significantly higher values were obtained ( P  < .05) for the white blood cells (WBC), heterophils, lymphocytes, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and aspartate aminotransferase (AST) in the dry versus the rainy seasons while there were significantly lower values obtained for red blood cells (RBC), glucose and total protein. Statistically significant differences in lymphocyte and monocyte counts were however found between adult and juvenile snakes. Differences in parameters for hepatozoon positive and hepatozoon negative snakes were not statistically significant although parameters like the total WBC count, heterophils and lymphocytes were markedly higher for hepatozoon positive snakes while packed cell volume (PCV) was slightly lower. This is the first study on blood parameters of the African rock python and serves as first pilot values for clinical assessments and future studies of this species.