What is your scientific explanation about the reason of "stomach protrudes from the mouth" for the following fishes?
Injuries caused by changes in pressure are called barotrauma. The top picture appears to be a Sebastes, which are physoclistous. Physoclistous fish have no connection between the swim bladder and the intestinal system, and thus their regulation of the bladder is slow.
Dear Khaled,
These are more or less lower columnar fish, wherein there is some amount of pressure on it due to the overlying water column. As they are caught and brought above the surface of water, that pressure is lost & hence the stomach comes out & protrudes from its mouth. The swim bladder also plays its role in this, as it expands under lower pressure ( & this is a sudden process) - when the fish is brought to surface.
This is a "normal" phenomenon which happens when fish are brought to the surface. Often seen in fish caught by line. Certainly not a fish disease!
I agree with Chandravadan Trivedi. It is very common to deepwater fish when they are brought to surface quickly.
I also agree with Jean -Lou Justine, it is a common occurrence in fishes when they are abruptly brought to the surface.
I agree, but it happen usually with trawl fishing because fishes are usually alive and the net is pulled up very quickly
The question has been well answered as expressed by those who have answered earlier.
Es un fenómeno relacionado con la extracción de peces desde aguas profundas, asociado a los cambios de presión.
The reason is Boyles Law - pressure and volume of gas are constant, so if pressure decreases, volume of gas increases - thus the gas in the swim bladder expands and the resulting increased internal pressure forces the stomach out of the mouth. It only happens with physoclist (closed) swim bladders. It is aided by Henrys Law - the gas dissolved in the blood comes out of solution as bubbles. If you look carefully you will find that the fish have bubbles in their blood vessels.
Injuries caused by changes in pressure are called barotrauma. The top picture appears to be a Sebastes, which are physoclistous. Physoclistous fish have no connection between the swim bladder and the intestinal system, and thus their regulation of the bladder is slow.
Injuries caused by changes in pressure are called barotrauma. The top picture appears to be a Sebastes, which are physoclistous. Physoclistous fish have no connection between the swim bladder and the intestinal system, and thus their regulation of the bladder is slow.
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