Do Fish Feel Pain?

Do fish feel pain? This topic has been debated by scholars for decades. Some people believe that fish are incapable of experiencing pain, while others believe that they are indeed capable. Some people believe they do not have very complex nervous systems and therefore do not feel pain to the extent that we do or perhaps even not at all. However, this idea is not completely accurate.  There has been some research that indicates that fish have the same kinds of specialized nerve fibers that mammals and birds use to identify tissue damage and thus pain. From all the information I have gathered I personally believe that fish can feel pain. Experiments show that fish respond when they are hurt, and pain relievers cause there behavior to change drastically. I would like to state that I am not against fishing what so ever, I realize that fish are an essential part to modern day civilization. What I do think, however, is that fish should be treated in a more humane manner.  For instance there have been fortifications put in place in order to protect birds and mammals, that do not include fish.  I believe this is largely due to the identity fish have. They are viewed differently than animals like cows, and chickens. In my opinion this doesn't make any sense, they are no less an animal and therefore deserve to be treated accordingly.






Sources:

1) http://www.biologynews.net/archives/2010/11/17/researcher_explores_whether_fish_feel_pain.html<script 
2) http://www.daviddarling.info/encyclopedia/V/vertebrate_nervous_system.html
3) http://www.bishops.k12.nf.ca/wells/vfish/projects/nervous/SENSES.html

Osmoregulation in Freshwater Fish

Freshwater fish absorb water passively and release it actively. Meaning they acquire water using no energy, but in order to release it they need to use energy. This process is due to fish's kidneys.  Their kidneys gain water osmotically. Meaning they absorb water by osmosis, which as I touched on before, is a type of passive transport. Fish's kidneys also produce dilute urine in order to get rid of waste matter.  Fish are in a constant state of osmosis, because they are hypertonic. This is not good because water continues to diffuse into fish, creating a very high concentration of water in their system. Fish deal with this problem with their kidneys. Fish's kidneys have a big surface area which enables them to reduce the concentration of water in their blood. However in order to do so they need to release important ions out of their bloodstreams, making it necessary to absorb ions such as salt back in. These two functions require energy meaning they use active transport.

Sources:
1) http://www.biology-online.org/5/1_animal_water_regulation.htm
2) http://www.cartage.org.lb/en/themes/sciences/zoology/animalphysiology/osmoregulation/osmoregulation.htm
3) http://en.wikipedia.org/wiki/Fish
4) Image http://www.incikefali.net/uremegocu-en.htm