Blue Resources for Aquaculture, Environment and Society DevelopmentEgyptian Journal for Aquaculture2090-78779320190901The use of vermicompost in cultivation and production of Spirulina platensis1115378510.21608/eja.2019.16905.1005ENRehamAbdelhayLimonolgy Department, Central laboratory for Aquaculture Research, ARCYasserMoustafaLimonolgy Department, Central Laboratory for Aquaculture Research, ARCEntsarEL-Metwaly EssaPlant nutrition, National Research Centre, NRCJournal Article20190912The cyanobacterium Spirulina platensis is quite spread all over the world due to its high nutritional value. It has been used as a protein source and vitamin supplement in healthy diet, in aquaculture and fisheries. Cyanobacterium Spirulina is capable to grow in various kinds of culture media. Furthermore, decomposed organic and inorganic nutrients media have been proven to be a good source of culture medium for Spirulina by many researchers. In this work, S. platensis was cultivated using dry vermicompost from fish sludge (VCFS) or cow manure (VCCM). 100 g of dry vermicompost from each source (VCFS/VCCM) collected and compared with Aiba and Ogawa liquid medium which was used as a culture medium. The results obtained showed that the highest protein and "chlorophyll a" ratio of S. platensis were observed in the biomass harvested from T2 (VCCM) and T3 (Aiba and Ogawa liquid medium). The highest dried S. platensis biomass was harvested from T2 (VCCM) while the lowest came from T1 (VCFS). The chemical composition ( as % of dry weight) revealed that (VCCM) was higher in total phosphorus, total nitrogen and organic matter than (VCFS).https://eja.journals.ekb.eg/article_53785_07525925d8cf6d1f45f91bed18d6da73.pdfBlue Resources for Aquaculture, Environment and Society DevelopmentEgyptian Journal for Aquaculture2090-78779320190901Effect of dietary supplementation of extracted jojoba meal on hematology , biochemical parameters and disease resistance in Nile tilapia (Oreochromis niloticus) infected by Aeromonas hydrophila13315378610.21608/eja.2019.16408.1002ENIsmail A.SarhanDepartment of pharmacology- faculty of veterinary medicine zagazig universitySayed A.Abdel-AzizDepartment of pharmacology - faculty of veterinary medicine - zagazig universityAhmed A.SaidDepartment of pharmacology - faculty of veterinary medicine - zagazig universityAbdel-Aleim F.Abdel-AleimDepartment of pharmacology - faculty of veterinary medicine - zagazig universitySomayah M.Awaddepartment of fish health and management- central lab for aquaculture- Abassa - Abo-hammad- EgyptJournal Article20190829The activities of extracted jojoba meal were evaluated experimentally via using 240 Oreochromis niloticus that were distributed into 4 equal groups (each of sex replicates), Group l, Group 2, Group 3 and Group 4 fed on balanced diet supplemented with extracted jojoba meal by (0, 0.5, l and 2 g /kg) respectively. Hematological, Biochemical parameters, survival and disease resistance were determined . Blood samples were collected from the experimented fish , 30, 45 and 90 days from the time of the experiment to measure Red blood cell (RBCS) count, Hemoglobulin (Hb), Hematocrit (PCV) value, White blood cell (WBCS) count, Total protein, Albumin, Globulin, and A/G ratio. The protective effect of the jojoba meal was evaluated via challenge test using pathogenic A. hydrophila. Result relived that survival and disease resistance (%) were significantly increased in group supplemented with Extracted jojoba meal compared with control (Group l). The RBCS count, Hb, PCV value, WBCS count, Total protein, Globulin showed significant increase in all supplemented ( G 2,G3, G4) compared with control (G 1). On the other hand, a Significant decrease in Albumin value and A/G ratio has been observed in all supplemented groups (G2 ,G3,G4) compared with control. The challenge test showed increase level of protection in the all supplemented groups compared with control. These results revealed that supplemented with extracted jojoba meal could be a potential, provide increasing in hematology, biochemical parameters, and disease resistance of O. niloticus in aquaculture.https://eja.journals.ekb.eg/article_53786_288a2350cf1198389ae6b66d3d4d5b59.pdfBlue Resources for Aquaculture, Environment and Society DevelopmentEgyptian Journal for Aquaculture2090-78779320190901Effect of different levels of folic acid on the growth and some physiological aspects of Nile tilapia "Oreochromis niloticus"33456503210.21608/eja.2019.19184.1008ENAdel M.ShalabyFish Reproduction and Physiology Department, Central laboratory for Aquaculture Research, Agriculture Research Center, EgyptAmany AGhareebFish Reproduction and Physiology department, Central laboratory for Aquaculture Research, Agriculture Research Center, EgyptMaaly MAbd El-RahmanFish Biology and Ecology Department, Central laboratory for Aquaculture Research, Agriculture Research Center, EgyptEman A. A.Abd El-HamidLimnology Department, Central Laboratory for Aquaculture Research, Agriculture Research Center, EgyptJournal Article20191106Folic acid is an essential vitamin in fish nutrition, and its lack or excessive intake may cause physiological disorders that reduce growth and production. Therefore, this study was conducted to evaluate the effects of different levels of folic acid (10, 20, 40, 80 and 160 mg/kg of dried rations) and compare it with the control group (0.0 folic acid) on the specific growth rate (SGR), weight gain (WG) and some physiological measurements in fingerlings of Nile tilapia; Oreochromis niloticus.<br /> The experiment was designed in six groups in glass aquaria, each group in three replicates each with 10 fingerlings (20-30 g) after acclimation in laboratory conditions. Fish in each replicate was weighed and each group was fed with the processed feed to the extent of satiation twice a day for 8 weeks. At the end of the 8th week, fish weights were taken in each replicate separately to calculate the specific growth rate and weight gain. Blood samples were taken for physiological examinations.https://eja.journals.ekb.eg/article_65032_911059789716505ed2d1c70d7f9cdf64.pdfBlue Resources for Aquaculture, Environment and Society DevelopmentEgyptian Journal for Aquaculture2090-78779320190901The effect of Yucca schidigera extract dietary supplementation on growth performance, feed and protein utilization of European seabass, Dicentrarchus labrax, fingerlings15315637310.21608/eja.2019.56373ENBassem KhalilElkhayatDepartment of Fish and Animal Production, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.Abdallah TageldeinMansourDepartment of Fish and Animal Production, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.Walied MohamedFayedDepartment of Fish and Animal Production, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.Eglal AliOmarDepartment of Fish and Animal Production, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.Abdel Aziz MoussaNourDepartment of Fish and Animal Production, Faculty of Agriculture, Alexandria University, Egypt.Journal Article20191101A total of 180 apparent healthy European seabass, <em>Dicentrarchus labrax</em>, fingerlings (5.0±0.5 g fish<sup>-1</sup>) were used to investigate the effect of different levels of Yucca, <em>Yucca schidigera, </em>extract (YE) on growth performance, feed utilization and survival rate. Yucca extractwere used at level of 0, 0.25, 0.50 and 1 g YE kg<sup>-1</sup> diet for 45 days. The fish were reared in twelve glass aquaria (three replicates per treatment), measuring (70x40x30 cm; approximately 70 liters each) at an initial stocking density of 15 fish aquarium<sup>-1</sup>. The aquaria were supported with artificial aeration and the water exchange rate was 15% with saline ground water (32‰). The results indicated that YE dietary supplementation significantly improved final weight, weight gain and specific growth rate in groups fed on 0.50 and 1 g YE kg<sup>-1</sup> diet compared to the control. Feed intake tended to increase with all groups fed on YE supplemented diet. The feed conversion ratio and protein efficiency ratio improved significantly with the highest two level of YE compared to the control. From the above mentioned, it can be concluded that YE can be used at level of 1 g YE kg<sup>-1</sup> diet as feed additive in sea bass fingerlings diet for improving growth performance and FCR and protein metabolism and maintaining survival rate.https://eja.journals.ekb.eg/article_56373_1305164d7905380a7cf518731595f9cb.pdfBlue Resources for Aquaculture, Environment and Society DevelopmentEgyptian Journal for Aquaculture2090-78779320190901Morphological studies on prevailing parasitic infections in the greater lizard fish Saurida undosquamis from the Red Sea47696743910.21608/eja.2019.18069.1006ENWalaa TalaatEl-EkiabyCentral Laboratory for Aquaculture Research, Agricultural Research Center, Egypt.Journal Article20191011Two hundred and seventy specimens of the marine greater lizard fish Saurida undosquamis were collected during the period from October 2018 to April 2019 from Red Sea at Suez province, Egypt. Fish were subjected to clinical, postmortem and parasitic examinations. The total parasitic infestation rate was 87.4%.The isolated parasites were one species of Microsporidia (Glugea sp.) with infestation rate 23%; one species of digenetic trematode (Lecithochirium grandiporum) with infestation rate 34.4%; one species of adult cestode (Oncodiscus sauridae) with prevalence rate 9.6%. The total prevalence rate of cestode larvae was 67.7%; three species of larval cestodes (Tetraphyllidean larvae; Pseudogrillotia sp. and Floriceps sp.). Tetraphyllidea plerocercoid and Trypanorhyncha Plerocrcoid larvae infection rate were 59.6% and 40.4 % respectively. The total prevalence rate of larval nematodes infection was 39%. Two species of larval nematodes (Anisakis simplex larvae and Echinocephalus overstreeti) with prevalence rate 89.5% and12.4% respectively. The histopathological alterations due to different parasitic agents were studied.