Farming of Tilapia in Ponds;

Tilapia farming involves the culture of the following species:

(i)             Oreochromis niloticus

(ii)           Oreochromis mossambicus

(iii)          Oreochromis aureus

(iv)         Oreochromis spilurus

(v)           Oreochromis andersonii

(vi)         Tilapia zillii.

(vii)        Tilapia rendalli

I). Feeding Habits

Tilapias are heterogeneous (i.e. varied) in their feeding. They are hardy (tough, resilient), have rapid growth, and have ability to consume and efficiently assimilate a wide variety of foods.

II). Maturation

In natural water bodies, tilapias mature in about two to three years. Under culture they tend to mature early. Sexual features distinguishing males from females are clear when fish mature (about 15 cm in Tilapia zillii and 10 cm in Oreochromis niloticus). Males have pointed papilla while females have flat horizontally slit papilla.

III). Fecundity

Fecundity refers to the number of eggs produced by a fish in a spawn. This applies well for monocyclic species, that is, once a year breeders. Tilapias are polycyclic (many times breeders) and their ovary may contain eggs at different stages of maturity.

Table 1: Some characteristics that differentiating substrate brooders (Tilapia) and mouth brooders (Oreochromis):

Characters Tilapia Oreochromis
Fecundity high Low
Egg diameter (mm) 1-1.5 up to 5.0
Yolk percentage less than 25% up to 45%
Yolk colour pale yellow Orange
Size of fry at feeding 5-6 mm 9-10 mm
Courtship prolonged (monogamous) brief (polygamous)
Juvenile mortality high Low
Longevity (life span) up to 7 years over 9 years