Observation

This question was attempted by many candidates and their performance was poor. Many candidates gave the importance of fish hatchery and not advantages of sourcing fish seed as required in Question 6(a). In 6(b), many candidates were stating how raceway are constructed, but didn’t state its advantages. In 6(c), candidates were stating general uses instead of stating their specific uses in artificial breeding. In 6(d), candidates were mixing fish feed ingredients with mineral and vitamin prefix and so gave wrong answers. For example many candidates wrote groundnut or rice instead of groundnut cake or rice bran.

The expected answers are as follows: 

(a)        Advantages of sourcing fish seed from a good hatchery
                       
-           High quality seeds are obtained
-           High growth rate
-           Disease resistant strains obtained
-           There is all year round availability

(b)        Advantages of using raceway over tanks in fish culture

-           Race way is for high density stocking
-           Access to good water quality
-           Constant aeration
-           Relatively cheaper to use
-           Quick removal of waste/debris

(c)        Uses of the following items in artificial breeding of fish
(i)         Hatching trough         
-           For incubation of eggs                       
(ii)        Happa                         
-           Holdingfish/broodstock
-           Nursing of fish larvae/for hatching
(iii)       Syringe                       
-           For injecting hormones                                  

(iv)       Microscope                 
-           For observing fish eggs/milt                          

(v)        Aquarium tank
For      
-           rearing fish larvae
-           holding broodstock
                                                                                                           

(d)       Ingredients that could be used to prepare fish feed

-           Maize/Corn                             -           Millet
-           Fish meal                                 -           Copra cake
-           Groundnut cake                      -           Soya bean cake
-           Rice bran                                 -           Wheat bran     
-           Sorghum                                  -           Blood meal
-           Vegetable oil           

(e)        Effects of low dissolved oxygen in fish pond water

            -           Piping of fish at the surface
-           Reduction of feed intake
-           Reduced growth of fish
-           Death of fish