Previous electron microscopic examinations of outer segments of photoreceptors suggest that many flattened saccules of cones are continuous with the cell membrane and that their lumina connect with the extracellular compartment but that most saccules in rods appear to lack these connections. The saccules probably contain photolabile pigment, and certain potentials appear to result from dipole f...

Previous research has shown stable isotope ratios of nitrogen in fish and other animals may vary depending on their food source. Ecologists have had some success in determining feeding and trophic relationships within an ecosystem using stable isotopic ratios. In this study, nitrogen stable isotopic ratios were measured in populations of Lepomis macrochirus (Blue Gill) in Kentucky Lake Reservoi...

Low-frequency sinusoidal linear acceleration (0.08 Hz, ±4 mG) modulates skin sympathetic nerve activity (SSNA) in seated subjects (head vertical), suggesting that activation of the utricle in the peripheral vestibular labyrinth modulates SSNA. The aim of the current study was to determine whether SSNA is also modulated by input from the saccule. Tungsten microelectrodes were inserted into the c...

There are approximately 50 muscles that control tail fin shape in most teleost fishes, and although myotomal muscle function has been extensively studied, little work has been done on the intrinsic musculature that controls and shapes the tail. In this study we measured electrical activity in intrinsic tail musculature to determine if these muscles are active during steady rectilinear locomotio...

The elaboration of enamel matrix glycoprotein was investigated in secretory ameloblasts of incisor teeth in 30-40-g rats. To this end, the distribution of glycoprotein was examined histochemically by the use of phosphotungstic acid at low pH, while the formation of glycoprotein was traced radioautographically in animals sacrificed 2.5-30 min after galactose-(3)H injection. Histochemically, the ...

Cisplatin (CDDP) is known to have toxic effects on the inner ear. There has been numerous reports of hearing disturbances and cochlear damage following CDDP treatment, but very few concerning vestibular disturbances. In this study, guinea pigs were injected peritoneally with either 5 mg/Kg or 10 mg/Kg CDDP. Pathological changes were observed immediately after CDDP administration. SEM investigat...

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown, and understudied due to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for p...

Flavobacterium columnare is the causative agent of ‘columnaris disease’ (Davis 1922), a disease that kills or debilitates a wide ecological and phylogenetic spectrum of temperate and tropical freshwater fish (Bernardet 1989; Bernardet & Grimont 1989; Bernardet et al. 1996; Olivares-Fuster et al. 2007; Bullard, McElwain & Arias 2011). It is regarded as a predominant pathogen of fish maintained i...

Information is lacking on preserving fish carcasses to minimize postmortem autolysis artifacts when a necropsy cannot be performed immediately. The purpose of this study was to qualitatively identify and score histologic postmortem changes in two species of freshwater fish (bluegill-Lepomis macrochirus; crappie-Pomoxis annularis), at varied time intervals and storage temperatures, to assess the...