Abstract:
The study was carried out to assess the dietary effect of date seed oil on the reproductive
performance of Clarias gariepinus broodstock with the average body weight (554.23±3.87g). Date
fruit (Phoenix dactylifera) were purchased at Oba market in Akure, Ondo State. The seed were
removed from the fruits, sundried, grounded into fine powder and extracted the oil using soxhlet
extractor and n-hexane as solvent. Five diets with 40% crude protein were formulated with
different inclusion level of Phoenix dactylifera seed oil. Control diet (D 1 ) has 0 g/100g of the feed,
while test diets D 2 , D 3 , D 4 and D 5 had 0.5, 1.0, 1.5, 2.0g/100g respectively. The experiment was
carried out for a period of 70 days and total number of 30 female C. gariepinus broodstock were
randomly distributed into 10 concrete tanks (2 x 2 x 1.25) m3 at a stocking density of three fish per
tank in duplicate per treatment. The fish were fed at 3% of body weight twice a day between the
hour of 08:00-9:00hr and 16:00-17:00hr and constant water level of 1m was maintained. Each
group was batch-weighed every two weeks using a weighing balance. The experimental design
was completely randomized design. Water quality parameters which include pH, temperature and
dissolved oxygen were determined every week. At the end of the feeding trial, weight gain, gonad-
somatic index and reproductive indices (percentage fertilization, hatchability, survival, and
fecundity) as well as histological estimation were determined. The fish fed D 3 had the highest
weight gain (9452.28±27.22), percentage fertilization (99.83±0.18), hatchability (60.38±4.20) and survival (75.88±19.83), while the weight of the ovaries of the fish fed D 4 had the highest value
(171.17±28.34) with fecundity of (11.68±1.85x10 4 ).The control diet D 1 had the lowest in most of
the parameters. There was late perinucleus and mature vitellogenic stage in the ovarian histology
of the fish fed diets D 2 , D 3 , D 4 and D 5 ,which is the stage of ocyte growth characterized by the
formation of egg yolk proteins and their accumulation in the ooplasm compeared with the control diet D 1 which have early perinucleus stage. This study revealed that dietary inclusion of Phoenix
dactylifera seed oil improves fertility in Clarias gariepinus which will improve fish seed
production.
