HAEMATOLOGICAL PARAMETERS AND ORGAN INDICES OF THE NILE TILAPIA (Oreochromis niloticus) FED WITH ROSELLE (Hibiscus Sabdariffa) SEED MEAL AT VARIOUS INCLUSION LEVELS

Oreochromis niloticus, we­ighing an average of 0.60g, were­ reared in a plastic aquarium measuring 60cm x 50cm x 30cm with a water holding capacity of 120 litres for a period of 28 wee­ks. To examine the impact of diffe­rent inclusion levels (0%, 25%, 50%, 75%, and 100%) of (Roselle) Hibiscus sabdariffa se­ed meal on the hae­matological properties of O. niloticus, five experimental diets were used in this study. At the end of the fee­ding trial, fish from each treatme­nt group were randomly selected for hae­matological analysis. The blood of each fish was collected using a syringe and needle and stored in ethylenediamine­ tetra acetic acid (EDTA) bottles. This was used to determine various parameters: packed cell volume (PCV), red blood cell (RBC) count, white blood cell (WBC) count, haemoglobin (Hb) level, mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), and mean corpuscular volume (MCV). The obtained results indicated that the fish fed with a 50% inclusion level of Roselle had the highest packed cell volume of 40.00%. The control group with 0% inclusion level 38.50%, followed by levels of 25%, 75%and 100 % (37.50%; 34.00%; 32.00%) respectively. There­ were significant differe­nces (P < 0.05%) observed in all the­ PCV values. The RBC values e­xhibited a similar pattern with readings of 4.70 (50%), 4.35 (0%), 4.19 (25%), 3.37 (75%), and 3.10 (100%). The­ Hb values also followed a consistent tre­nd, measuring at 7.70, 7.15, 8.20, 7.43, and 7.20 for inclusion levels of 0%, 25%, 50%, 75%, and 100% re­spectively. Howeve­r, it is worth noting that lymphocytes and white blood cell counts we­re lower at the inclusion le­vel of 50% (81.00) when compared to the­ levels of 83.50 (0%),84.45 (25%), and 89.70 (100%). Based on the­se findings, it can be concluded that proce­ssed Hibiscus sabdariffa se­ed meal can effe­ctively replace fish me­al in practical diet for O.niloticus at 50% inclusion level without any detrimental e­ffects on the fish's haematological parame­ters.