fish

Tag archives for fish

Dr. Michael Tobler and Dr. Zach Culumber at Kansas State University examined 112 species of live-bearing fish (Poeciliidae) and have made some interesting discoveries about their evolution. Their analyses included information on body shape, fin size, where the species are found and information on global climate. What they discovered is that the evolution of female fish is…

Who would have thought tiny fish could lead to big advances in medicine? Zebrafish (Danio rerio) and mammals have similar anatomy and physiology of the brain, eyes, gut, and cardiovascular systems. Some of the reasons why these fish are good models to understand cardiovascular physiology were recently explored in a new article published in Physiological Reviews.…

Improving endurance exercise

We all know that aerobic exercise is good for us because it helps improve muscle function and our ability to move well. For fish, aerobic exercise helps animals escape predators, catch prey as well as improve reproduction success. When we exercise, our muscles adapt by altering the metabolism of energy, the way calcium is handled as…

Growing meaty fish

Similar to humans, muscle growth in fish is increased with exercise. Unlike humans, however, teleost fish are able to continue growing in length as well as weight throughout their lives. This type of meat, I mean muscle, growth happens in two ways: 1) muscle cells get bigger and 2) new muscle cells form. Researchers at the University of Barcelona in…

We tend to think of carbon monoxide (CO) only in terms of being a poisonous gas. The reason for its toxicity is due to its ability to bind really tightly to our hemoglobin molecules, which prevents oxygen from being able to bind. In mammals, CO also decrease breathing rate. As you can imagine, it is a pretty terrible…

Teleost fish living in saltwater environments are constantly compensating for water loss. This happens because their surroundings have higher concentrations of salts than their plasma and the rule of thumb in Biology is: water follows salt.  Thus these fish must somehow compensate for water loss in order to prevent dehydration. One way they do this is by…

Seawater contains sulfate concentrations that are nearly 40 times those measured in plasma. Therefore, it is easy to see why fish would need to develop mechanisms to keep sulfate within a physiologically normal range. The kidneys of teleost fish have been known to excrete excess sulfate in the urine. However until now, it was not known whether…

Still going strong…here are the highlights from several sessions held on Day 4: John Eme (California State University, San Marcos) presented data testing the effects of varying temperatures mimicking overwintering conditions on embryonic development of Lake whitefish. He found that indeed exposure to variable incubation temperatures between 2-8 deg C resulted in increased mortality. Moreover, the embryos hatched…

Why so many of us sleep

A special thank you to reader Dr. Barbara Goodman, Professor of Physiology at Sanford School of Medicine of the University of South Dakota who sent me a story from The Scientist about sleep in animals complete with footage of a dolphin that was seen apparently “sleeping” (video posted on YouTube): Why do animals sleep? This is a question with many…

Exercise grows bigger fish

A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology explored the effects of exercise on growth and hormone regulation in gilthead sea bream (Sparus aurata). The main hormones that regulate growth are, perhaps not surprisingly, growth hormone and insulin-like growth factor. Researchers discovered young gilthead seam bream that underwent…