Effect Of Water Hardness On Egg Fertilization, Incubation And Hatchability Of Clarias Gariepinus And Heterobranchus Longifilis
ABSTRACT
Effect of water hardnes on egg fertilization,
incubation and hatchability of virgin farm raised Clarias gariepinus and
Heterobranchus longifilis was investigated. Artificial breeding was carried out
by hormone inducement (Ovaprim at 0.5ml/kg fish). After latency period of 10
hours the eggs were stripped and mixed with milt from the males and incubated
at 27C water temperature differently in plastic containers with incubating
media prepared at various hardness of 20, 80, 160, 300mg/l CaCO; for five days.
Each concentration had three replicates. Water of 8mg/l CaCO, and pH 6.9 was
used as dilution water. Eggs having green dark brown colour after 10 hours of
placement in water were considered to be fertilized. Hardness of 160 and
300mg/l CaCO, showed increase in fertilization success in C. gariepinus but
failed to hatch successively while H. longi.filis recorded fertilization
success at 20 and 80 mg/l hardness. Hatching was monitored and was considered
to have commenced when 3% of the fertilized eggs had hatched. The mean hatching
rate fluctuated between 8% at hardness of 300mg/l and 70% at hardness of 80mg/I
in C. gariepinus and 3% at 300mg/l and of 47% at 20mg/l CaCO; in H. longifilis.
The highest hatching rate of 70% was recorded at 80mg/l CaCO, in C. gariepinus
while the highest hatching rate of 47% was observed at 20mg/l CaCO, in H.
longifilis.
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UDEH, N (2023). Effect Of Water Hardness On Egg Fertilization, Incubation And Hatchability Of Clarias Gariepinus And Heterobranchus Longifilis. Repository.mouau.edu.ng: Retrieved Nov 23, 2024, from https://repository.mouau.edu.ng/work/view/effect-of-water-hardness-on-egg-fertilization-incubation-and-hatchability-of-clarias-gariepinus-and-heterobranchus-longifilis-7-2
NNAEMEKA, UDEH. "Effect Of Water Hardness On Egg Fertilization, Incubation And Hatchability Of Clarias Gariepinus And Heterobranchus Longifilis" Repository.mouau.edu.ng. Repository.mouau.edu.ng, 15 Sep. 2023, https://repository.mouau.edu.ng/work/view/effect-of-water-hardness-on-egg-fertilization-incubation-and-hatchability-of-clarias-gariepinus-and-heterobranchus-longifilis-7-2. Accessed 23 Nov. 2024.
NNAEMEKA, UDEH. "Effect Of Water Hardness On Egg Fertilization, Incubation And Hatchability Of Clarias Gariepinus And Heterobranchus Longifilis". Repository.mouau.edu.ng, Repository.mouau.edu.ng, 15 Sep. 2023. Web. 23 Nov. 2024. < https://repository.mouau.edu.ng/work/view/effect-of-water-hardness-on-egg-fertilization-incubation-and-hatchability-of-clarias-gariepinus-and-heterobranchus-longifilis-7-2 >.
NNAEMEKA, UDEH. "Effect Of Water Hardness On Egg Fertilization, Incubation And Hatchability Of Clarias Gariepinus And Heterobranchus Longifilis" Repository.mouau.edu.ng (2023). Accessed 23 Nov. 2024. https://repository.mouau.edu.ng/work/view/effect-of-water-hardness-on-egg-fertilization-incubation-and-hatchability-of-clarias-gariepinus-and-heterobranchus-longifilis-7-2