Browsing by Author "Noorazilah Haris"

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    Biofloc as a potential natural feed for shrimp postlarvae
    (International Biodeterioration and Biodegradation, 2016) Helena Khatoon; Sanjoy Banerjee; Gregory Tan Guan Yuan; Noorazilah Haris; Mhd Ikhwanuddin; Mohd Azmi Ambak; Azizah Endut
    In this study, the suitability of excess biofloc that was discarded as waste from Litopenaeus vannamei farm effluent was investigated for effectiveness as a dietary replacement in rearing L. vannamei postlarvae (PL). A commercial shrimp diet (control) was compared to four diets containing dried waste biofloc at 25%, 50%, 75% and 100% replacement levels and fed to shrimp PL to evaluate the survival rate, growth performance and nutritional composition. Total ammonium nitrogen and nitrite nitrogen were maintained in culture tanks with minimal water exchange throughout the experiment. Results showed that PLs fed with 50% biofloc feed (50% BF) had significantly higher (p < 0.05) specific growth rate compared to the other treatments. In addition, PLs fed with 50% and 75% BF had significantly higher survival rate (p < 0.05) compared to those fed with commercial feed only. However, protein content of PLs fed with 50% and 75% BF was comparable to those of 100% commercial feed. This study demonstrates that waste biofloc has potential to be used as a cost effective feed for rearing shrimp PLs.
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    Effects of different salinity on the growth & proximate composition of dunaliella sp. at different growth phase
    (Universiti Malaysia Terengganu, 2014) Noorazilah Haris
    Dunaliella sp. can tolerate different degree of salt stress and can be used in large scale cultivation and may be applied for specific uses. Thus in this study, the effect of different salt treatment (10, 30 and 50 ppt) on the growth and biochemical composition of Dunaliella sp. at different growth phase was investigated. Results showed that Dunaliella sp. growth in term of cell density and optical density was significantly higher at 10 ppt (9.39 x 10 6 cells mr') compared to 30 ppt (7.59 x 10 6 cells mr 1 ) and 50 ppt (9.18 x 10 6 1 cells mr ). In addition, Dunaliella sp. grew faster and growth phase shorten in lower salinity compared to higher salinity. The variation of salinity tested had influenced on the biochemical composition of Dunaliella sp..