3. Results
3.1. Growth performance
The growth performance and feed utilization data for the African
catfish fed the four diets are set out in Table 4. There was a
significant difference (P< 0.05) between the final average
body weights between fish fed the control diet D1 and the
other groups. Fish fed the fishmeal based control diet (D1)
and D2 demonstrated the highest mean final body weight
70.52 and 60.92 g, respectively compared with the other two
diets D3 and D4 containing 20% and 30% of Ulva these fish
weighed, 40.57 and 35.66 g, respectively. There was also a significant
difference (P < 0.05) in the final length observed
between fish fed on the control group D2 and on the other
two diets, with results ranging between 19.90 and 17.11 cm
(Table 4). The specific growth rate (SGR%) values further supported
this trend, with SGR reducing from 2.73 for the fish fed
on the control diet to 2.69, 2.11 and 1.91 for the fish fed on the
other three diets (Table 4) with also, insignificant differences
(P > 0.05) between D1 and D2. The condition factors (K) ranged
between 0.92 and 0.674, although no mortality was
observed during the experimental period and the overall health
of the fish appeared normal.