How to draw blood from fish

I would like to share about my experience in taking fish blood for an experiment. It actually a funny story though. That day we have an experiment that require us to take blood from fish. My friend and I was very exited. Easy to say that, that was our first time. We don't know the correct way to do it. So we do as we pleased. Then you know what happen? Only three out of the pail fishes were a live! And none of us success to draw any blood from the fish. But all the student that try to draw the blood from the fishes were soak with the fish water. Can you imagine how hard and how we handle the fish that badly. I feel very sorry for the fishes. Then I think it actually better if I know how to do it correctly, just for preparation in case I have to do it a gain.

This are few step.

1.Place the fish in the holding tank.
2. Wait until the fish loses balance and swims abnormally
3. Squeeze the peduncle of the fish gently and observe the response

• If the fish attempt to swim away, wait until it stops responding to pressure
• If the fish does not respond, proceed with the directions

4. Have an assistant hold the fish upside down with the tail facing in your direction.
5. Grasp the peduncle of the fish at the base of tail fin with one hand and hold it so that the body of the fish is straight.
6. Position the needle with the other hand so that the needle is aim at the axial ventral peduncle, about an inch behind the anal fin.
7. Tilt the needle so that the needle is at 45 degree angle from the peduncle.
8. Insert the needle into the skin and between the scales of the fish.
9. Push the needle straight down towards the center of the body.
10. STOP when you hit a hard, impenetrable surface, this is the vertebral column.

11.Withdraw the needle no more than a millimeter.

12.Gently pull back on the plunger. 

• If the blood does not appear in the needle, withdraw the needle and repeat steps 1-9 
• If blood does appear in the needle, maintain pressure on the plunger and proceed with the direction

13.Release the plunger once the desired amount of blood has been drawn.

14.Place your thumb on the body of the fish above the needle.

15.Simultaneously withdraw the needle from the fish and apply slight pressure with your thumb.

16.Once the needle has been completely withdrawn, press down firmly on the area of puncture for five seconds OR until bleeding stops.

17.Place the fish into the recovery tank.

I hope next time I will do it properly...