Growth Performance and Haematological Response of Oreochromis niloticus Fed Varying Inclusion Levels of Ocimum gratissimum as Additive

Abstract

Abstract

This study was carried out to evaluate the use of Ocimum gratissimum leaves on the growth performance 3 and haematological parameters of Oreochromis niloticus juveniles. Five tanks (21.5x14.5x9cm ) containing 10 Oreochromis niloticus juveniles were fed with five isonitrogenous diets (27.11% crude protein) containing varying inclusion of O. gratissimum (Control diet 0%, O. gratissimum T1=25%, T2=50%, T3= 75%, and T4= 100%). The fish were fed twice daily for an experimental period of 12 weeks. The fish in tank T3 (0.23inclusion of O. gratissimum) had the best weight gain 26.00±3.00g which ranges from 22.00±1.00 to 26.00±3.00g. The highest specific growth rate of 0.56±0.06 was recorded in tank T3with a range of 0.52±0.01 to 0.56±0.06. The highest food conversion ratio 1.25±0.09 was recorded in tank T1 (25%0.075 inclusion of O. gratissimum) with a range of 1.11±0.23to 1.25±0.09. The highest protein efficiency ratio 0.03±0.01was also recorded in T3 (0.23 inclusion ofO. gratissimum) with a range of 0.03±0.00 to 0.03±0.01. No mortality was recorded in all experimental tanks. The fish fed with O. gratissimum showed increase in haematological values of 4 2 Red blood cell (RBC), (0.02±0.00 10 µL), and White with blood cell (WBC), (15.25±0.007 10 µL) compared to the values of fish fed with control diet Red blood cell (RBC) was 0.01±0.00 and White 2 blood cell (WBC) was 12.65±0.07 10 µL. There was a reduction in the haematological value of the fish fed with O. gratissimum in Haemoblogin (HBG), (4.45±0.07 g/dL) compared to the value of fish fed with control feed Haemoblogin (HBG), (5.15±0.14 g/dL). The genotoxicity test that was carried out showed that the highest counts of micronucleus were present in tank T4 while the lowest counts of micronucleus were found in tank T0. A significant difference was recorded (p<0.05). It is concluded that using O. gratissimum leaves as feed for O. niloticus enhances the growth of the fish and has no negative impact on the health status of the fish. Therefore partial inclusion of 0.23kg of O. gratissimum to 100kg of fish feed should be encouraged because its contributed to the growth of fish and is of medicinal value.