Abstract:
This study assessed the dietary effects of baker's yeast, Saccharomyces cerevisiae on growth
performance, haematology and pathogenic- induced stress in African catfish, Clarias gariepinus
fingerlings. Fish feed was formulated to meet 40% crude protein requirement for African catfish
fingerlings. All dietary ingredients were weighed including Saccharomyces cerevisiae in the diet
at 0% (control), 5%, 10%, 15%, 20% and 25% labelled as SCH0, SCH5 SCH10, SCH15, SCH20,
and SCH25 respectively. Ten apparently healthy African catfish were distributed into eighteen
rectangular plastic tanks (30 x 15 x 10) cm 3 after acclimatization for a week. Each treatment
contained 10 fish/tank in triplicate which were fed twice daily at 5% body weight for 70 days at
800- 900GMT and 1700-1800GMT. Fish were batch-weighed every two weeks using a weighing
balance (Metler TOLEDO, Pb8001 London). Water parameters were taken using, Hanna pH
/EC/TDS/Temp, multi-parameter kits (H19830). After the expiration of the feed trials, fish were
exposed to pathogenic strain of Aeromonas hydrophila. Ten fish were randomly selected from
different dietary treatments and injected with 1ml of the Aeromonas hydrophila (MPSTR 2143,
mildly pathogenic strain) and observed for one week. Also, growth performance, proximate
analysis, histological examination, and haematological of fish were carried out using standard
methods. Data obtained were subjected to one way analysis of variance (ANOVA) using SPSS 20
and the mean were found significant at (p<0.05). Duncan’s multiple Range Test was used to
compare the differences among the means. Result showed that there was significant differences in
growth indices (p<0.05). Also, blood parameters and glucose concentration were significantly
different (p<0.05) with yeast inclusion. Furthermore, no adverse effect was observed on the
intestinal morphology of fish fed with Saccharomyces cerevisiae, hence, fish fed with 25% of
Saccharomyces cerevisiae performed best in the study. Therefore this study showed that the best
supplementation in the diet of C. gariepinus level was SHC25 which contained 25% of
Saccharomyces cerevisiae.
