Observation

This question was attempted by majority of the candidates and their performance was good. Many candidates however seem not to clearly understand the demand of the Question 1(b) as many could not state the structural differences between Cat fish and Tilapia fish. In Question 1(a) and 1(c) many candidates gave correct answers. Candidates also failed to use correct terminologies such as using ‘Whiskers’ instead ‘Barbels’.

The expected answers are as follows: 

(a)        External similarities of specimen A (African catfish) and specimen B (Tilapia)

-           They are both streamlined in shape/they have streamlined shape
-           They both have fins
-           They have opercula/they each have operculum
-           They both have eyes/pair of eyes
-           They both have tails fins/caudal fins
-           They both have nostrils
-           They both have terminal mouths
-           They both have lateral lines
-           They both have spiny fins                              

(b)        External structural differences between specimen A (African catfish) and
specimen B (Tilapia)

                                                                                               
(c)        Reasons why specimen A (African catfish) is culturable

-           They can reproduce in captivity/induced spawning
-           Can tolerate poor water conditions
-           They are hardy
-           They can accept artificial feed
-           Have high survival rate
-           They have resistance to diseases and parasites
-           High fecundity/highly prolific/lay many eggs