The Effects of Salinity and Pharmaceuticals on the Physiology of the Sheepshead Minnow (Cyprinodon variegatus)
Abstract
Natural and anthropogenic stressors in the environment, such as salinity and pharmaceuticals, may affect fishes in sublethal ways measurable through non-invasive swim tunnel respirometry. This method quantifies aerobic metabolism which represents the confines within which all oxygen-requiring processes (e.g. growth and reproduction) occur. Critical swimming speed (Ucrit) is also measured and further determines fishes’ ability to forage, evade predators, and migrate. Three experiments using Sheepshead Minnow (Cyprinodon variegatus, SHM) were conducted to determine the metabolism and swimming performance of freshwater and saltwater acclimated SHM, SHM exposed to the pharmaceutical prednisone and a control for 7 days (short-term), and 21 days (long-term). In the salinity experiment, no significant differences were seen between groups, but interesting trends emerged. In the short-term prednisone experiment, no differences were present, but changes in aerobic metabolism, swimming efficiency, and anaerobic metabolic capacity were seen when preliminary data of long-term prednisone exposed fish were compared with short-term prednisone exposed fish. These results show that SHMs tolerate a wide range of salinities and while short-term prednisone exposure had no effect on SHMs, long-term pharmaceutical exposure affects some of the measured parameters. These studies further support the use of swim tunnel respirometry for understanding how stressors affect fish physiology, and ultimately survival, in sublethal ways.
Subject
Sheepshead Minnowsynthetic glucocorticoids
swim tunnel respirometry
osmoregulation
metabolism
swimming performance
pharmaceuticals
Citation
Cubbage, Taylor Lindsey (2019). The Effects of Salinity and Pharmaceuticals on the Physiology of the Sheepshead Minnow (Cyprinodon variegatus). Undergraduate Research Scholars Program. Available electronically from https : / /hdl .handle .net /1969 .1 /194460.