Preparation for cold shock*
The water Temperature in degree celcius
The milt and chopped testical (catfish's).
Pour the milt onto a muslin cloths and wrap it.
Pour the saline solution as the milt is squeeze and the extract pour along with saline onto the eggs
Squeeze more...
Mixed them thoroughly using a chicken feather.
After 3 minutes, treat the fertilized eggs with 5 degree celcius of fresh water.
Then Pray... that your heater works. Because...
It is monsoon. Wind and rain and work hazard. Being worried is just part and parcel of dealing with living things.
* Cold shock is induced in fertilized egg in the hope to produce a triploid organism. Imagine the eggs had a 1N nucleus(functional) and a 1N polar body(not functional). The sperm is another 1N. During normal fertilization, the 1N polar body extrude out of the ovum once the sperm enter the egg. Now what if... the time when all the 3N is in the ovum (the 1N nucleus, the polar body and the sperm)... and a shock trigger the ovum to response by hardenning the outer membrane causing the polar body and sperm to trap in the ovum... hence 3N.
But it this time when all 3N can be together is brief. it can be from seconds to minutes. Many had proven they can produce triploid this way, but how about survival?
This I am going to find out.
woooo, chopped testicles...so wats the result now?
ReplyDeleteThe normal fertilized eggs(diploid) had roughly 80% survival. Exposure to 5 degree Celsius for 40 and below around 30-40% survival. Survival for 60 minutes is about 5 larvae fish from 300-500 fertilized eggs. Ammonia around .5 to 1.0 mg/L everyday. hence, 25% water change.
ReplyDeleteyeah. need to chopped them or cut them up so they release the sperm. previously my friend threw the whole testicles into the eggs... very low fertilized eggs and hatched larvae
u're a catfish scientist?
ReplyDeletehi j_yenn,
ReplyDeletei am a bachelor degree of aquaculture student. a small part of my study involve fish.
because of my final year project dealing with the african catfish, i need to read as many, study as many, and collect as many data as possibly available(limited research and costly articles a hinder but can be overcome)
the best part would have been data analysis.
the stressful part would be improving my experiment design, encountering disease and death...
it was easier to the heart and soul and mind to kill the fish by damaging its brain or central nervous system than...
to see them got sick, had to make decision to either kill it or heal it. then after treating them, had to make decision whether they are strong enough to be put back with the other big fish(the treatment will weaken them), then when they get hurt again and you have to face the possibility of surviving somewhere bellow 10%... all the effort is...
it is sad to see something struggling to their death and felt so hopeless to do anything. this is aquaculture.
we are taught to face the impossibility in life.
wah. i asked you a four-word question only leh. if this is how you answer your exam questions, no problem, can survive easily :P
ReplyDelete=D, just a bit stressful that's why type so much. my exam don't have this. i don't know. i don't want to just survive... i want to grow.
ReplyDelete