Stress and reproduction inBoiga irregulariswith notes on the ultrastructure of the sexual segment of the kidney in squamates

Abstract

The reproductive tract of wild-caught male Boiga irregularis (Merrem, 1802) (Brown Treesnake) and the changes that result in these tissues from captivity are described. Wild-caught snakes were compared with snakes kept in captivity and sacrificed at approximately 10, 30, 50, and 60+ days. Snakes sacrificed after 10 days in captivity showed no differences in histological appearance or epithelial height in either the testis or sexual segment of the kidney (SSK) compared with wild snakes. Normal spermatogenic stages and SSK ultrastructure were observed in the testes and kidney from wild specimens and captive specimens after 10 days. In terms of the SSK, large electron-dense secretory vacuoles occupied the apices of the epithelial cells, while a basal nucleus, rough endoplasmic reticulum, and Golgi bodies filled the bases of these cells. All SSK cells were actively secretory in a mode that could most accurately be termed apocrine. At time of secretion, released vacuoles become diffuse and the apical membrane ruptures, spilling the SSK contents into the distal nephron lumen. Between 10 and 30 days in captivity, spermatogenesis and secretion in the SSK ceased and the epithelial height of both tissues decreased. At approximately 60 days, testicular epithelial height increased and spermatogenic activity was reestablished. The SSK, however, remained regressed at 60 days.

The sexual segment of hemidactylus turcicus and the evolution of sexual segment location in squamata

“…Since the first description of the SSK by Gampert (1866), numerous studies have been conducted detailing the morphology of the SSK in squamates. The nephron structure is similar to what has been described in most squamates with the SSK being limited to the distal portions of the uriniferous tubules (Anderson,1960; Misra et al,1965; Sever et al,2002; Krohmer,2004; Siegel et al,2009). Inconsistencies observed in the exact location of the SSK within squamates have confounded the terminology used in keeping synonymous nomenclature between lizards and snakes.…”

“…Subsequently, the SSK has been found in the kidney ducts of all male snakes and lizards (Squamata) that have been examined and is considered a secondary sexual characteristic (reviews by Saint Girons,1972; Fox,1977; Aldridge et al, in press). Research has been conducted investigating the morphology and physiology of the sexual segment in many squamates, but only nine studies have investigated ultrastructural characteristics of the SSK, five on snakes (Kühnnel and Krisch, 1974; Sever et al,2002; Krohmer,2004; Sever et al,2008; Siegel et al,2009), and four on lizards (Furieri and Lanzavecchia,1959; Del Conte and Tamayo,1973; Gabri1983; Sever and Hopkins,2005).…”

Observations on the Sexual Segment of the Kidney of Snakes with Emphasis on Ultrastructure in the Yellow‐Bellied Sea Snake, Pelamis platurus

“…The mode of secretion varies, although the most common mode is apocrine. The appearance of the mature secretory vacuoles also is quite variable and may be electron lucent as in B. irregularis (Siegel et al, 2009b); uniformly electron dense as in S. pygaea (Sever et al, 2002), H. turcicus (Rheubert et al, 2011), and P. platurus; biphasic as in C. lemniscatus (Del Conte and Tamayo, 1973), N. natrix (Kü hnel and Krisch, 1974), N. sipedon (Krohmer, 2004), and S. lateralis (Sever and Hopkins, 2005); or consist of both electron lucent and electron dense vacuoles, as in P. taurica (Gabri, 1983) and A. piscivorus (Sever et al, 2008).…”

“…Ultrastructural studies are fewer and limited to Lacerta siccula (Furieri and Lanzavecchia, 1959), Cnemidophorus lemniscatus (Del Conte and Tamayo, 1973), N. natrix (Kü hnel and Krisch, 1974), Podarcis taurica (Gabri, 1983), Seminatrix pygaea (Sever et al, 2002), Nerodia sipedon (Krohmer, 2004), Scincella lateralis (Sever and Hopkins, 2005), Agkistrodon piscivorus (Sever et al, 2008;Siegel et al, 2009a), Boiga irregularis (Siegel et al, 2009b), and Hemidactylus turcicus (Rheubert et al, 2011).…”

Agkistrodon piscivorusspermatogenesis addendum: The effect of Hurricane Katrina on spermatogenesis of the western cottonmouth snake

“…Prolonged stress can terminate spermatogenesis 5 , and it is therefore probable that the stressful effect of hurricane Katrina induced hormonal changes that caused spermatogenic arrest, as observed by Graham. 1 (their Fig.…”