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Friday, April 20, 2012

African Catfish Breeding


Assalamualaikum And Good Evening,,


Today i was given a task to demonstrated and teach undergraduate student how to practice artificial propagation in African catfish. First of all we need to know about African catfish. Scientific name of African catfish is Clarias gariepinus. Before we further doing breeding, we need to know how to differentiate male and female breeders.

Female (Left)    Male (Right)
Genital papillae for male is protruding and coned shape, for female is rounded shape. To doing breeding, we need to choose gravid (matured) female and male. How to know it already gravid?? By looking at their external appearance, we can see genital papillae of male reddish and for female reddish and also the abdomen is bloated and smooth. After choosing the right gravid fish, we need to acclimatize the fish together in a tank or aquarium one week prior to breeding activity or injection.

To do the breeding for example today this morning at 9 am, we need to inject it 8-12 hour prior to injection. So last night around 12-1 am, me and a squad doing injection for the class today. From my reading about this breeding activity good to do at night and injection in the evening. Below is the steps:

(1) Weighing the fish



(2) Calculate amount of hormone based on their weight (Female 0.5 ml/kg, Male 0.25 ml/kg)



(3) Suck out the hormone with proper size of needle and syringe


(4) Intramuscular injection near dorsal fin of the fish


(5) Transfer injected male and female into separated tanks or aquarium to avoid fighting and disturbed the female.


Breeding night squad

In the next day i have opportunity to demonstrate and teach how to do artificial propagation in African Catfish.  After finish briefing we continue the breeding activity.


Briefing

(1) Check maturity of the female (green colour eggs = immature, brownish or brownish pinkish = matured)

Ready matured female


(2)  Stripping
A Thailand student holding the fish for stripping process 
Matured eggs after stripping
 (3) Male operation to take out gonad (milt and sperm)

use sharp knife and make small cut

Then use sharp scissor to make big open
Cut both gonads

Wash the gonads with freshwater to avoid contamination

(4) Make small pieces cut of the gonads into gauze



(5)  Squeeze the gonads to take milt into a bowl containing eggs 



(6) Dry method fertilization



 (7) Add some freshwater



 (8) Distribute the fertilized eggs into incubation aquarium, better to have mosquito net.




Done,,, then i'm going to observed it.  I take it some sample then observed it in my room...

Because of long time sample in the sampling bottle the eggs coagulated


We will see it will hatch or not Tomorrow...

Continue..






2 comments:

  1. Hi Eddy,

    I would like to personally thank you for helping me to handle the induced spawning practical class while I'm coordinating the FYP presentation. All the students enjoyed the class very much. Keep up the good work & all the best for your future endeavour!

    Best wishes,
    Dr. Natrah JAQ

    ReplyDelete
  2. Tq Dr.
    Its my pleasure to teach them. Thanks for the opportunity Dr., it is also my learning process also. Happy to teach them..:)

    ReplyDelete