Histological Investigation of Swim-bladder Morphology and Inflation in Cultured Larval Striped Trumpeter (Latris lineata) (Teleostei, Latridae)

Abstract

Histological techniques revealed that primary swim-bladder inflation in Latris lineata, a Tasmanian marine finfish, occurred before first feeding (Days 6 to 8 after hatch, depending on culture conditions). The histological appearance of the swim-bladder altered markedly after inflation; the lumen lining changed from columnar epithelium to predominantly squamous epithelium with an anterior crescent of cuboidal epithelial cells forming the gas gland. The pneumatic duct traversed ventrally from the posterior end of the swim-bladder and entered the intestine at the junction of the oesophagus and the intestine. The columnar epithelium persisted in non-inflated swim-bladders, and proliferation of the underlying vascular system caused the epithelium to fold and fill the entire lumen.