Histochemical and quantitative study of the cloacal glands of Triturus marmoratus marmoratus (Amphibia: Salamandridae)

Abstract

The cloacal glands of the male marbled newt Triturus marmoratus marmoratus were studied during winter and summer by histochemical and quantitative histologic methods. Four types of glands were distinguished: pelvic, dorsal, ventral, and Kingsbury's glands. The pelvic and dorsal glands have an eosinophilic epithelium and secrete neutral mucins. The ventral and Kingsbury's glands have a basophilic epithelium and secrete acid mucins. The lectin‐histochemical characterization of the carbohydrates secreted by the four gland types revealed that the secretion of both the pelvic and Kingsbury's glands contain β‐GalNAc in the peripheral region of the oligosaccharide, and that the dorsal glands secrete a glycoprotein with α‐GalNAc. The ventral gland sections did not react to any of the lectins used here. The quantitative study revealed that the cloaca undergoes seasonal variations in volume, being significantly larger in winter than in summer. The total volume occupied by both the pelvic and ventral glands, as well as their tubular diameter, are also significantly greater in winter, while these parameters do not vary in dorsal and Kingsbury's glands. No seasonal differences were observed in the height of the epithelium in any gland