Meeting Abstract
While there is a rich body of work examining the functional properties of the teleost feeding apparatus, it is surprising how little we know about the composition of connective tissues within the teleostean feeding elements. Whereas mammals are known to have discrete categories of connective tissues, including hyaline cartilage with abundant extracellular matrix and dense regular connective tissue that has few cells and many extracellular fibers, in contrast, teleosts have a wide spectrum of connective tissue types, including tissues that resemble mammalian cartilage but vary in their amounts of matrix, matrix composition, number of cells, and cellular morphology. The main goal of this study is to determine the cellular morphology and biochemical makeup of the primary feeding elements in the first and second visceral arches (mandibular and hyoid) of three cypriniform species: Carassius auratus (goldfish), Danio rerio (zebrafish), and Cyprinus carpio (koi). Cypriniforms have unique strategies for suction feeding, and this study seeks to elucidate tissue morphology, structure, and function of their feeding elements. A combination of several histological staining techniques was used to learn more about the chemical composition of the tissues, and the staining patterns were documented. Positive Alcian blue and periodic acid-Schiff (PAS) staining of the hyoid bones indicates an acidic, cartilage-like makeup of the extracellular matrix. Additionally, several interhyoid ligaments stained positively for elastin, suggesting that stretch is important for hyoid depression during suction feeding. This work thus provides a basis for future functional morphological studies on teleostean connective tissues associated with suction feeding.
