REALISTIC INTERPRETATION OF CONDITION FACTOR USING STOMACH CONTENT ANALYSIS OF Clarias gariepinus IN GWALLAGA RIVER, BAUCHI – NIGERIA

Abstract

The predictive power of condition factor (k) as a biomathematical model (BM) was investigated using a case study of
stomach content analysis (SCA) of Clarias gariepinus in Gwallaga River, Bauchi, Nigeria. The river was divided into
four stations: Headwater (A), Upper middle (B), Lower middle (C) and Tail water (D). Ten fish were caught fortnightly
from each station during the dry season. Eighty fish were collected during the period of the research. Lengths and
weights of the fish were measured. The fish were dissected, stomach contents were identified. The stomach repletion
levels (SRL) were categorized into five (0, 25, 50, 75 and 100%). The SCA of C. gariepinus revealed Phytoplankton
had the highest importance index of 489.3273 out of the seven feed items. X
2 = 26.078 (P > 0.05) showed that there
is an association between SRL of the fish and their stations. This was supported by the high k-value of fish from station
A (k = 1.1889) but fish from other stations had low k-values with observed low SRL. It was concluded that this research
has realistically tested the predictive power of k as a BM through SCA because nutrition contributes strongly to the
physiological well-being of an organism.