ORIGINAL_ARTICLE
Purification and Characterization of a Thermostable β-Mannanase from Halophilic Aspergillus terreus strain ARSA Associated to a Mangrove Plant of Red Sea Coast, Egypt, and its Application in Mannooligosaccharides Production and Juice Clarification
Mangrove-associated fungi are of great significance in industries due to their various and versatile enzyme production. So, this work studies the purification of β-mannanase produced by a halophilic Aspergillus terreus strain ARSA (accession No. MN075514) isolated from marine sediment of mangrove, Safaga, Red Sea coasts, Egypt. The enzyme was precipitated by 50% acetone, followed by purification using gel filtration on Sephadex G-100 yielding an active major protein peak showing 6.77-fold purification. The molecular weight of the purified β-mannanase was approximately 48 kDa, determined by a sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Km and Vmax values were found to be 3.33 mg/ml and 1666.67 U/ml, respectively. The optimum pH and temperature of the purified enzyme were 6.5 and 60oC, respectively. The enzyme was stable from pH 5.0 to 7.5 and partially stable up to 80oC. The effect of activators and inhibitors was studied providing that EDTA, Hg2+, Tween 80, and SDS (10%) strongly inhibited the enzyme activity, while Mg2+, Mn2+, and Na+, enhanced enzyme activity. Mixtures of mannooligosaccharides are resulted from the hydrolysis of locust bean gum by the enzyme. Crude and purified A. terreus ARSA β-mannanase gave promising results on fruit juices clarification as on apple juice extraction with a yield of 128.32 and 167.65%, respectively.
https://ejabf.journals.ekb.eg/article_209588_fc99c41484671544d83d7b001f7c394e.pdf
2021-12-01
1
16
10.21608/ejabf.2021.209588
Aspergillus
β-mannanase
Mangrove
Purification
Mannooligosaccharides
juice clarification
Aida
Farag et al.
1
AUTHOR
ORIGINAL_ARTICLE
Quality evaluation and safety of little tuna fish shawarma
The quality and effect of using two different recipes with and without fat (T1, T2, T3 and T4) of fish shawarma processed from little tuna fish (Euthynnus alletteratus) were determined during frozen storage at -18ºC for three months. The analysis was carried out at an interval of 15 days. A significant decrease (P≤0.05) in the values of moisture, protein, lipid, and pH was correlated with increasing the duration of the frozen storage period. While ash and carbohydrate were significantly increased (P≤0.05) with an increasing storage period. The values of cooking loss, TVB-N, TMA-N and TBA were significantly increased (P≤0.05) after 3 months of the frozen period. However, significant decreases (p≤0.05) of fish shawarma in the water holding capacity (WHC), cooking yield and microbial parameters occurred periodically during the frozen storage till its end. Sensory examination indicated that the cooked fish shawarma samples kept their integrity well. Panelists rated the color and taste of shawarma in the next ranking T1> T2> T3> T4, although shawarma samples were desirable, their color intensity was intense. In conclusion, the first recipe (T1) without adding fat was the best one, however, more researches on processing and improving the quality of fish shawarma are essential to provide an insight into the consumer’s purchasing patterns.
https://ejabf.journals.ekb.eg/article_209932_f8f628daf55c3719b575cdbb0859da8c.pdf
2021-12-01
17
31
10.21608/ejabf.2021.209932
Fish shawarma
Euthynnus alletteratu
Sensory evaluation
tuna
Mohamed
M. M. Khallaf et al.
1
AUTHOR
ORIGINAL_ARTICLE
Comparative Physiological Aspects of Plasma Hemostasis of some Commercial Fish Species
The hemostasis system is designed to ensure the integrity of the internal environment of the body and bleeding control and maintain the liquid state of blood in the vasculature. Clinicodiagnostic characterization of clotting in different fish species contains incomplete and scarce information in modern biological science. The data obtained revealed some issues of functioning of the ancient mechanism of blood clotting in these animals in both evolutionary and veterinary aspects. Thus, a comparative study was conducted on the functional state of plasma hemostasis in some commercial fish; namely, cartilaginous ganoids sturgeon (Acipenser baerii), hybrid of sterlet (Acipenser ruthenus), starred sturgeon (Acipenser stellatus), bony – common carp (Cyprinus carpio) and the tilapia, Oreochromis niloticus. The following coagulogram parameter changes were addressed: thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), the concentration of fibrinogen, and soluble fibrin monomer complexes (SFMC). It is assumed that the functioning of the plasma hemostasis system has species specificity regardless of stress resistance, especially in commercial fish at different evolutionary stages. Hence, species-specific characteristics of fish clotting were determined. Activation by the common and extrinsic pathways was several times faster in cartilaginous ganoids (reduced TT by 17.8-26 times, PT by 1.9-2.6 times, reduced fibrinogen concentration by 4.8-6.11 times) than in both the species of bony fish. The hemostasis, with activation of the intrinsic pathway (APTT), was faster in the hybrid and the tilapia by 20.6-16.8 times compared to that in sturgeon, and by 2.8 and 2.2 times compared to carp. The SFMC content in all fish was (1.3-4.3 times) higher than that noted in dogs and 2.5-8.3 times higher than the SFMC content in humans. But, it was lower (1.0-2.4 times) compared to that recorded in cattle. The highest/lowest values of SFMCs were detected in carp and the hybrid of A. ruthenus and A. stellatus, respectively.
https://ejabf.journals.ekb.eg/article_209965_785e2e64bd8aa7863a79e5a703ace289.pdf
2021-12-01
33
41
10.21608/ejabf.2021.209965
Clotting
Coagulogram
Blood
carp
Sturgeon
tilapia
Daria
Igorevna Berezina
1
AUTHOR
Luybov
Leonidovna Fomina
2
AUTHOR
ORIGINAL_ARTICLE
Development of the parasite nematode Echinuria uncinata (Nematoda: Acuariidae) in the intermediate host Daphnia magna, in Uzbekistan
The current study is the first to record that larvae of the nematode Echinuria uncinata were found in Daphnia magna species in the Fergana Valley, Uzbekistan. Zooplankton specimens of Daphina magna were collected using hydrobiological methods from the Sariqamish Lake shoreline and the adjacent pond areas (9 spots) in spring and autumn, 2019-2020. It was noticed that 11.5% of the samples were infected by nematode larvae. To detect the impact of infection on the intermediate host, samples were subjected to morphological and morphometric parameters.[A1] In addition, the development of larvae was addressed in the intermediate host, D. Magna. The infected nematode eggs were supplied with food and their development was studied at different temperatures. After 24- 26 days, at low temperatures (1-15°C), the fourth invasive stage was reached. While, on days 9-10 of the experimental period, and at 20-22°C, the invasive stage was recorded. Meanwhile, on days 8-9 days at a relatively high temperature of 24-26° C[A2], the same stage was noted.
https://ejabf.journals.ekb.eg/article_210299_5207e9c05680da85a60141c3d0325e20.pdf
2021-12-01
43
48
10.21608/ejabf.2021.210299
Nematode
Invasive larva
Intermediate host
Daphnia magna
Maqsadjon
J. Madumarov et al.
1
AUTHOR
ORIGINAL_ARTICLE
Antimicrobial and antifouling activities of the cellulase produced by marine fungal strain; Geotrichum candidum MN638741.1
Fungi are one of the most important groups of marine microorganisms used to produce important enzymes and antimicrobials. Industrially, the cellulase produced from marine fungi plays an impotent role; however, using it medically is very limited. Hence, this study aimed to use purified and characterized cellulase enzymes produced from Geotrichum candidum strain Gad1 to determine their antimicrobial and antifouling activities. The maximum cellulase activity was achieved (55.54 U/ml) with maximum specific activities (325.8 U/mg). The highest antimicrobial activity of cellulase was 42 mm diameter of zone inhibition found against Vibrio damsel as antibacterial, and19 mm diameter of zone inhibition observed against Aspergillus niger as an antifungal. By using 600 ul/l of cellulase, the high reduction of the bacterial load in the formed biofilm was shown. The data obtained during the present study confirmed the potential of fungal cellulase. The cellulase enzyme produced by G. candidum strain Gad1 demonstrated promising antibacterial, antifungal and antifouling properties.
https://ejabf.journals.ekb.eg/article_210301_8dee38736c4b16b0837e621b585f0ab2.pdf
2021-12-01
49
60
10.21608/ejabf.2021.210301
Ahmed
M. Gad et al.
1
AUTHOR
ORIGINAL_ARTICLE
Influence of Water Temperature and Salinity on Rearing of Nile Tilapia Fry under Biofloc Culture System
Nile tilapia fry (1.45 g each) were subjected to four salinity treatments (0.5‰, 5‰, 10‰, 15‰) under two temperature regimes (Statistical analysis: two-way ANOVA). Nile tilapia fry grew to harvest weights of 3.92 to 8.12 g/fingerling after 60 days of rearing. Tilapia fry reached higher harvest weights and daily weight gains when raised within 5-10 ‰ salinity range than those reared in 15 ‰ salinity. Among all treatments, there was an adverse effect of the highest salinity (15‰) on the growth performance of tilapia fry compared to other salinities. The better growth performance of Nile tilapia fry underwater salinity of 5-10% can be ascribed to the ease of osmoregulation under those salinities. Nile tilapia fry had better feed conversion ratio FCR performance when reared under high-temperature conditions (2.05-2.22) within the salinity range of 0.5-10% when compared to those of low temperature (3.04-5.38). Feed conversion ratios were deteriorated (4.01-5.74) when fry were raised in water salinity of 15 ‰ due to the adverse effect of increased salinity. The protein efficiency ratios were also better under high temperatures when fry were raised in 0.5-10 ‰ salinity range. Biofloc volumes were optimal and lower under high temperature and increased at low temperature due to the negative effect of low temperature on bacterial metabolism. Rearing Nile tilapia in biofloc system reduced ammonia and nitrite concentrations to recommended levels. Consequently, it is recommended to rear Nile tilapia fry under optimal range of salinity and temperature when reared in biofloc systems.
https://ejabf.journals.ekb.eg/article_210384_61505d4f844e1131511719a5ff8d1462.pdf
2021-12-01
61
77
10.21608/ejabf.2021.210384
Biofloc
Fry
Nile tilapia
Temperature
salinity
M. A.
Elnady et al.
1
AUTHOR
ORIGINAL_ARTICLE
Insecticidal, Repellency, and Histopathological Effects of Four Extracts of Clove Oil (Syzygium aromaticum) Against Culex pipiens (Diptera: Culicidae)
Solvent extraction, a classic method to separate different components, was used in this study. Clove (Syzygium aromaticum) was macerated using four solvents, namely, water, petroleum ether, ethyl acetate, and ethanol, to extract the essential oil. The insecticidal and repellent activities on third-instar larvae and adult females of Culex pipiens were investigated. Based on LC50, water extract was more active (LC50 = 39 ppm) against larvae. The highest efficacy of the repellent solvent of the clove extract against adult females was 28%. The ultrastructural effect was studied on the cuticle, muscles, and midgut of third-instar larvae. The tested larvicide showed histopathological changes in the treated larvae compared with the untreated ones. Thus, the water extract could be a good candidate and promising alternative in control programs of mosquitoes, especially against Cx. pipiens in Egypt and other developing countries.
https://ejabf.journals.ekb.eg/article_210806_555155f17a11bc5922d025d5f68af092.pdf
2021-12-01
79
96
10.21608/ejabf.2021.210806
Culex pipiens
histopathology
larvicidal
repellent
Syzygium aromaticum
El Gohary
E. El Gohary et al.
1
AUTHOR
ORIGINAL_ARTICLE
Length-weight relationship and population parameters of the sea bream, Sparus aurata (Linnaeus, 1758) in Abu Qir Bay, Mediterranean Sea, Egypt
The present work aimed to study some biological and population parameters of Sparus aurata in Abu Qir Bay, Alexandria to understand the status of its stock and give essential information to assess proper management for this species in the bay. A total of 1029 random specimens of gilt-head sea bream, S. aurata were monthly collected from commercial catch in the landing site at Abu Qir Bay during the period from January 2020 to January 2021. For each fish sample, total length (cm) and total weight (g) were measured, and scales were used for age determination. The total scales’ radius and the radius of each annulus were calculated to the nearest 0.01 cm. The back-calculation method was used to estimate growth in length and weight at the end of each year. Results of the length-weight relationship showed that the growth of S. aurata in Abu Qir Bay fishery is nearly isometric (b: 3.01). The longevity of S. aurata was more than 5 years. The maximum increment of the linear growth occurred by the end of the first year of life (15.61 cm), but the maximum value of increment in weight (69.95 g) was recorded at age group IV+. Age groups I+ and II+ were the most abundant amounting 55.6% of its total catch. The length at first capture (Lc)was 18.96 cm. Total, natural and fishing mortality rates for S. aurata were 1.16 yr-1, 0.56 yr−1 and 0.60 year−1, respectively. Growth parameters were calculated as L∞ = 35.49 cm, K = 0.25 yr-1 and t0 = -1.27 yr. Exploitation rate (E = 0.52) indicates that the stock of sea bream was slightly higher than that optimally exploited stock.
https://ejabf.journals.ekb.eg/article_210808_3ee656dee2ef6b61bff96a63b7cf0660.pdf
2021-12-01
97
109
10.21608/ejabf.2021.210808
Sparus aurata
length-weight
population
age and growth
Mortality rates
Exploitation
Mohammed
G. Desouky et al.
1
AUTHOR
ORIGINAL_ARTICLE
A comparative study on gill histology and ultrastructure of the sea bass (Dicentrarchus labrax) inhabiting brackish, marine and hyper-saline waters
The present work was carried out to study the gill histology and ultrastructure of the seabass, Dicentrarchus labrax; and to compare between these structures in fish specimens inhabiting waters with different salinities. Fish specimens of the sea bass (D. labrax) were collected from Gholion Pond at Kafr El-Shiekh Governorate (Salinity: 18-20 ‰); Timsah Lake at Ismailia Governorate (salinity: 35-37‰) and Bardawil Lagoon at Al-Arish, North Sinai Governorate (Salinity: 64 ‰). Histological examination showed that the chloride cells in brackish waters are located within the epithelium of the inter-lamellar regions and secondary lamellae, but in marine and hypersaline waters they are located within the primary epithelium of the inter-lamellar regions. The flat elongated pavement cells of secondary lamellar epithelium in hypersaline specimens are more flattened than those in brackish and marine waters. The ultrastructure examination showed that chloride cells in specimens of brackish water are large; polygonal and ovoid in shape with a little population of mitochondria. While the chloride cells in specimens from marine and hypersaline waters displayed more rich populations of mitochondria. In marine and hypersaline specimens, each lamellar epithelium mostly consists of one layer of flat elongated pavement cell, while it consists of two layers in brackish water specimens. Results of statistical analysis to gill characteristic counts and measurements of D. labrax inhabiting waters with different salinities revealed that there are statistically significant differences between groups for most counts and measurements as well as their ratios, except that of the pillar system diameter. Generally, most of the multiple comparisons (brackish versus marine; brackish versus hypersaline or marine versus hypersaline) are significantly varied
https://ejabf.journals.ekb.eg/article_210812_152b742c40d88a573cd05fb7277ae360.pdf
2021-12-01
111
128
10.21608/ejabf.2021.210812
Seabass
Dicentrarchus labrax
Gill histology
Gill Ultrastructure
salinity
brackish water
Hypersaline
Sanaa
E. Abdel Samei et al.
1
AUTHOR
ORIGINAL_ARTICLE
Antioxidant, Antimicrobial and Cytotoxic activity of Some Common Seaweed along West Coast of Maharashtra
This study aimed to evaluate the antioxidative potential and antimicrobial activity of eleven seaweeds, including Sargassum ilicifolium, Sargassum tenerrimum, Stoechospermum marginatum, Padina tetrastromatica, Dictyota maxima, Gracilaria corticata, Acanthophora spicifera, Batrachospermum sp., Caulerpa peltata, Chaetomorpha crassa, Ulva lactuca. Sargassum ilicifolium, Sargassum cinereum, and Sargassum tenerrimum were studied for anticanser activity. Seaweed extracts were screened for their antimicrobial activity against the following pathogens: Klebsiella, Bacillus thrungenis, Psudeomonus sp < em>., and Streptococcus aureus. Antimicrobial activity was measured using ELISA microplate reader. In ethanol extract, Sargassum tenerrimum and Caulerpa peltata exhibited maximum inhibition on the growth of the tested Klebsiella species. The antioxidant potential of various seaweed extracts was determined using the DPPH and FRAP. In the present study, the DPPH activity was consistently higher in the methanolic extracts of Phaeophyta. The maximum percentage of radical-scavenging activity was observed in the Padina tetrastromatica. This study was designed to assay the cytotoxic activity of the extract from brown alga; namely, Sargassum ilicifolium, Sargassum cinereum and Sargassum tenerrimum against breast cancer cells MCF7 by using MTT assay. The research was performed as an in vitro study. The Sargassum cinereum showed the highest IC50 value compared to Sargassum ilicifolium and Sargassum tenerrimum. The seaweed extract can be used as promising anti-oxidative agents, anti-microbial and anti-cancerous in cosmeceutical or nutraceutical products which can upturn the value of an otherwise worthless weed.
https://ejabf.journals.ekb.eg/article_210814_d196876025937b3c525aca35b38188fb.pdf
2021-12-01
129
143
10.21608/ejabf.2021.210814
antioxidant
anti-microbial
Anti-cancerous
Seaweeds
Ahilya
Vitthal Waghmode et al.
1
AUTHOR
ORIGINAL_ARTICLE
Provisional Checklists on Blackwater Fish from the Peat Swamp in Terengganu, West Coast of Peninsular Malaysia.
The blackwater fish species endemic to the peat swamp is economically and ecologically important in Southeast Asia, notably Malaysia. This report is the first peat swamp fish species of Kampung Yak Yah, Kemaman, Terengganu, (KYYKT), west coast of Peninsular Malaysia, aimed to document the fish species richness and update the provisional fish checklist in Malaysia. All species were collected from several stagnant blackwater peat swamps. A total of 14 species of freshwater fish from six families were recorded, and the most dominant family recorded was Cyprinidae (n=7), followed by Osphronaemidae, comprised of four species. Meanwhile, other families of Anabantidae, Siluridae, and Zenarchopteridae contributed at least one species each. Hence, more species may be recorded in future studies applying other sampling methods, such as the electrofishing technique, and believably be able to add a few more fish species to the checklist.
https://ejabf.journals.ekb.eg/article_210853_024fb9d890debee2a709c8b49a7e8a18.pdf
2021-12-01
145
164
10.21608/ejabf.2021.210853
Peat swamp fish
species richness
Kemaman Terengganu
Peninsular Malaysia
Logging
Hussin-Jasmin
N. et al.
1
AUTHOR
ORIGINAL_ARTICLE
Reproductive Biology of the Brushtooth Lizardfish (Saurida undosquamis) (Richardson, 1848) Inhabiting the Northern Gulf of Suez and the South-Eastern Mediterranean Sea
The Brushtooth Lizardfish Saurida undosquamis is one of the economically successful Lessepsian species, which migrated from the Red Sea to the Mediterranean Sea. The present study was carried out from September 2018 till April 2019 in the Northern Gulf of Suez (at Suez) and from March 2018 to March 2019 in the South-Eastern Mediterranean Sea (at Port Said). A total of 838 specimens were monthly collected from both sites. Overall sex ratio was 1:0.40 and 1:0.54 for the Gulf of Suez and the Mediterranean population, respectively. There was a highly significant difference between the ratios of both sexes in both populations (P<0.001). The monthly changes in maturity stages and gonado-somatic index showed that S. undosquamis have a prolonged spawning season extending from December to April in the Gulf of Suez and from June to March, with two major spawns occurring in August and February in the Mediterranean Sea. The fish length corresponding to 50% (L50) was 17.3 cm for males and 18.2 cm for females from the Gulf of Suez, whereas it was 16.9 cm for males and 17.8 cm for females from the Mediterranean Sea. The absolute fecundity for the Gulf of Suez population ranged from 14750 to 63553 ova (average: 38075 ± 18181 ova) for fish that ranged from 20-22 cm to 30-32 cm (TL). For the Mediterranean Sea population, the absolute fecundity ranged from 18090 to 62025 ova (average: 39274 ± 15783 ova) for fish that ranged from 18-20 cm to 30-32 cm (TL).
https://ejabf.journals.ekb.eg/article_210928_965b24446e13bcb3c789146d5394a0a4.pdf
2021-12-01
165
180
10.21608/ejabf.2021.210928
Lessepsian migration
Saurida undosquamis
sex ratio
First maturity
Gonado-somatic index
fecundity
Alaa
A. Roshdy et al.
1
AUTHOR
ORIGINAL_ARTICLE
The variations of Clark and Gastrosomatic indexes of Glossogobius giuris living in some regions the Mekong Delta, Vietnam
This study lasted one year to describe the energy accumulating capacity and feeding intensity of Glossogobius giuris by analyzing the Clark index and Gastro-somatic (GaSI) indexes of this species. A total of 1,291 individuals were collected in four sites, including Cai Rang, Can Tho; Long Phu, Soc Trang; Hoa Binh, Bac Lieu and Dam Doi, Ca Mau. In each sampling site, fish were monthly caught using trawl nets from January to December 2020. The data analysis results showed that the fish species displayed high energy accumulating capacity due high value of the Clark index. This capacity varied between males and females, immature and mature groups, and four sites, but not between the dry and wet seasons as Clark changed with gender, fish size and location but not the season. With a high value of GaSI, the goby showed high feeding intensity. This fish showed intraspecific and spatiotemporal changes in feeding intensity since GaSI varied with fish size, season and location. The gender ´ season interaction affected GaSI but not Clark, whereas the reverse case was found in gender ´ site interaction. These indexes were influenced by the season-site interaction. The findings are helpful for fish’s adaption understanding and future artificial cultivation study.
https://ejabf.journals.ekb.eg/article_211009_c4a913f76b5bfa031a6749ce215cdf79.pdf
2021-12-01
181
191
10.21608/ejabf.2021.211009
Gieo
H. Phan et al.
1
AUTHOR
ORIGINAL_ARTICLE
Using the Otolith Mass in Growth Determining of Glossogobius giuris in the Mekong Delta
Otoliths played essential roles in fish growth determination but were limited to gobies living in the Mekong Delta, Vietnam (VMD). This study consequently lasted for one year from January to December 2020 in order to provide knowledge of morphology and mass of otoliths and their roles in growth determining for a commercial goby Glossogobius giuris in VMD. Samples were monthly collected using trawl nets in four locations from the fresh to brackish waters, including Cai Rang, Can Tho (0‰); Long Phu, Soc Trang (24.9‰); Hoa Binh, Bac Lieu (30.4‰) and Dam Doi, Ca Mau (30.8‰). Data analysis results of 1,291 individuals showed that the otolith mass was similar between left and right sides, but varies with gender, fish size, season and site. Due to high determination parameters, the otolith mass had positive relationships with fish dimension measurements such as weight, total length, eye diameter, body height, and head length. The findings showed otolith mass could be used as a growth indicator for this species.
https://ejabf.journals.ekb.eg/article_211034_182a47a910acd3135c1457e93f47351f.pdf
2021-12-01
193
203
10.21608/ejabf.2021.211034
Gieo
H. Phan et al.
1
AUTHOR
ORIGINAL_ARTICLE
Biochemical evaluation of the carp hypophyseal homogenate as spawning stimulator in teleosts
Hypophyseal homogenate of common carp is considered one of the different hormonal sources for spawning induction in the teleosts. The present work aimed to measure the hormonal concentration of the hypophysis in different carp species, which can be used as a source of hormones for spawning induction in teleosts. The hypophysis of different mature carp species (both males and females); namely, common carp (Cyprinus carpio), grass carp (Ctenopharyngodon idella) and silver carp (Hypophthalmichthys molitrix) were evaluated biochemically to discuss their hormonal source. Five hormones in the pituitary gland, including adrenocorticotropin hormone (ACTH), prolactin hormone (PRL), growth hormone (GH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were analyzed using electrochemiluminescence immunoassay (ECLIA). Compared to female carps, the hypophysis homogenate of male carps recorded lower levels of the measured hormones. The biochemical results showed that the hypophysis homogenate of H. molitrix showed higher levels of 426±13, 118±6, 2355±47, and 1005±35 ng/mg for PRL, GH, LH, and FSH, respectively. Whereas, lower level of ACTH (5±0.5 ng/mg) was recorded compared to those obtained in C. carpio and C. idella. However, the concentrations of those hormones recorded the lowest values in male carp fish, while the concentration of ACTH hormone was higher in male common carp, recording 13±1.2 ng/mg. The present biochemical observations revealed the suitability and effectiveness of the cheap silver carp hypophysis as a spawning inducer in fishes.
https://ejabf.journals.ekb.eg/article_211258_7744434e9951e101e645a49a2a9bc197.pdf
2021-12-01
205
214
10.21608/ejabf.2021.211258
Hormone
Hypophysis
carp
Biochemical analysis
Mohamed
F. Kora et al.
1
AUTHOR
ORIGINAL_ARTICLE
Effect of cooking methods and refrigeration conditions on quality and safety of the crayfish (Procambarus clarkii)
This work aimed to investigate the nutritive value, quality, and safety of raw and cooked crayfish (Procambarus clarkii) samples collected from several locations of the River Nile. The extracted meat of the crayfish tails was sampled to be examined. They were divided into two batches; the control samples (without any treatment), and the other batch in which samples were brined, rinsed with tap water, drained, spiced (with garlic, salt, lemon, and cumin), cooked, and stored in the refrigerator at 4±1ᵒC for 9 days. Based on their cooking methods (frying& microwave cooking), the refrigerated boiled tails were divided into two groups and compared to the control. The chemical composition, physicochemical, and microbiological quality of the raw samples were adjusted. The effect of cold storage on the safety and quality of the cooked samples was determined. The effect of the two cooking methods on the samples was also recorded. The recorded nutritive values of raw crayfish tails were addressed as follows: moisture = 78.61%, crude protein = 18.46%, fat = 1.58%, ash = 1.33%, carbohydrates = 0.02% and 65.08 mg\16 g N for total EAAs. Additionally, the values of quality and safety indices were recorded, including: pH (6.02), TVB-N (11.20 mg/100g), TMA (0.123 mg/100g), TBA (0.113mg MDA/kg) and TPC (185 cfu/g sample) on wet wt.. An apparent increase was detected in the total protein, fat, and ash with respect to both types of cooking, whereas water content recorded a progressive decrease, particularly in the fried samples. However, a little change was found throughout refrigeration storage. Remarkably, crayfish proved to possess a high quality and safety. Thus, the current study recommended using crayfish to fill the gap in the Egyptian fish market. In addition, the frying method was determined to be better than the microwave cooking method.
https://ejabf.journals.ekb.eg/article_211313_b3d0b692811e7021aa8304ed6c4d8ab1.pdf
2021-12-01
215
226
10.21608/ejabf.2021.211313
Crayfish
cooking methods
Quality
safety
Mahamed
Abou-Taleb et al.
1
AUTHOR
ORIGINAL_ARTICLE
The Effect of Bait Types on Catch per Unit Effort in Trapping the Oriental River Prawns (Macrobrachium nipponense)
Opera house traps are the most popular gear used to catch the oriental river prawns in the Anzali Lagoon, Iran. In this study, the effect of two kinds of baits attached to opera house traps was subjected to an evaluation from April to September 2015 in the Anzali Lagoon. The opera house trap was designed for catching the oriental river prawns. A total of 20 opera house traps were randomly set along the shoreline at intervals of approximately 3 m. Ten traps were set baited by bread, and ten traps were set baited by fish. Results showed that the mean catch per unit effort (CPUE) was significantly different between the two different baits (P < 0.05). The maximum CPUE was recorded in July (22.95) with bread bait. During the period time of each treatment, the CPUE did not show any significant difference (P > 0.05). In addition, the length-frequency distributions of M. nipponense in opera house traps, baited with fish and bread, showed no significant difference (P < 0.05). Therefore, there was no difference between bread and fish baits of any size for absorbing the prawn. Results showed that, due to most factors affecting the CPUE of M. nipponense, bread proved to be a better bait selection.
https://ejabf.journals.ekb.eg/article_211318_6c48684a54cd24fa4d39f4975de306b5.pdf
2021-12-01
227
234
10.21608/ejabf.2021.211318
TRAP
Bait
CPUE
Macrobrachium nipponense
Mehrnoush
Aminisarteshnizi
1
AUTHOR
ORIGINAL_ARTICLE
Effects of entrance design on catch efficiency of Hokkaido pot: a field experiment in Anzali Lagoon, Iran
In this study, the catch per unit effort (CPUE) of Hokkaido pot was compared with the oriental river prawn (Macrobrachium nipponense) in the Anzali Lagoon, Iran. Capture efficiencies and catch rates of the Hokkaido pot were compared during 2015. This field experiment investigated the effects of different entrance designs on the catch efficiency of Hokkaido pot (H1) by fishing with commercial Hokkaido pot (H2) (entrance inclination angle and number were different). The experimental pot was identical, in size and design, to commercial pots, apart from some difference in the entrance (Pots: H1: α = 45° and 90°, three entrance; H2: α = 90°, one entrance). Significant differences were detected between pots of H1 and H2 (P < 0.05). H1 pot yielded more than H2; however, no significant differences were recorded in the mean total length or the frequency distributions of the total length between both pot types (P > 0.05).
https://ejabf.journals.ekb.eg/article_211323_ffb1cda7ada8630a250c76e2749d4dc2.pdf
2021-12-01
235
242
10.21608/ejabf.2021.211323
CPUE
Macrobrachium nipponense
Pot entrance
Inclination angle
Hokkaido pot
Mehrnoush
Aminisarteshnizi
1
AUTHOR
ORIGINAL_ARTICLE
Length-weight relationship, morphometric and meristic controlling elements of three freshwater fish species inhabiting North-Western Himalaya
Length-weight relationship (LWRs) is a propondral index used to understand the general health of the fish through various growth-related indices, besides being helpful to compare different fish populations. In the present study, LWRs, morphometric and meristic elements of three food fish species, including Tor putitora (Chirak), Labeo dero (Karah)and Schizothorax richardsonii (Lass) and inhabiting the Rajouri River of North-Western Himalayan region were investigated. From June 2019 till May 2020, Specimens of T. putitora, L. dero, and S. richardsonii (45, 40, 40 individual/species, respectively)were collected by using gill and cast nets. Results showed that ‘b’ value for L. dero was 3.187 and for T. putitora was 3.102, indicating a positive allometric growth (b > 3). While, in the case of S. richardsonii, the ‘b’ value was recorded 1.915 with negative allometric growth (b < 3). The regression coefficient (r2) value was noted as 0.95, 0.94, and 0.91 for T. putitora, L. dero, and S. richardsonii, respectively. Moreover, the condition factor of all the three species was near to ‘1’, indicating the suitability of environmental conditions for better growth of these fish species. In addition, a total of 23 morphometric characters and 6 meristic counts were also analyzed, where morphometric characters showed a gradual increase with respect to body length, while the meristic counts remained constant with respect to the increase of body length. Data obtained can give a deep insight into the welfare of fish upon which a proper strategy can be affordable to manage and conserve fish population and their biomass.
https://ejabf.journals.ekb.eg/article_211325_fd9150a8e29a47b3566beca7d110166e.pdf
2021-12-01
243
257
10.21608/ejabf.2021.211325
Condition factor
Controlling elements
Food fish
Length-weight relationship
Rajouri river
Shahid
Mehmood et al.
1
AUTHOR
ORIGINAL_ARTICLE
Fishery Biology and Population Structure of the Blue Swimmer Crab, Portunus pelagicus, from the Red Sea, Egypt
More than 300 MT of blue swimmer crabs (BSC), Portunus pelagicus, are annually captured from the fisheries of the Egyptian Red Sea waters. During the last 20 years, a decline has been witnessed in the production of this species. For management purposes, information about the fishery's biology and population structure is required. Hence, monthly samples of P. pelagicus were collected from the commercial catch of Hurghada landing site, Red Sea, Egypt during the period from November 2017 to October 2018. A number of 1190 specimens were measured for morphometric relationships, sex ratio, age determination using carapace width frequency, population structure, mortality rate and exploitation ratio. The study revealed that P. plagicus was targeted by trammel nets and caught by a small bottom trawler as a by-catch. Carapace width- total weight relationship showed positive allometric growth (b-value= 3.10). Higher condition factors were observed in the small individuals. Four age groups were determined and age group +I was dominant by number (60.6%). Parameters of the von Bertalanffy equation were 21.19 cm, 0.414 year-1, and -0.998 year for CW∞, K and to, respectively. The carapace width at first capture was estimated (CW50 = 8.7 mm). The mortality rates were calculated as 2.929, 1.285 and 1.644 year-1 for total, natural and fishing mortalities, respectively. The blue swimmer crab fisheries on the Red Sea is over-exploited (E= 0.65) by the trammel net. Some management measures were suggested to maintain its stock for sustainability.
https://ejabf.journals.ekb.eg/article_211506_a8a8404fc5b88f4f7ffe2659b98ba71d.pdf
2021-12-01
269
283
10.21608/ejabf.2021.211506
Protunus plagicus
Fishery biology
population structure
Red Sea
Midhat
A. El-Kasheif et al.
1
AUTHOR
ORIGINAL_ARTICLE
Comparison of Catch per Unit Effort in three traps for fishing the Common Rudd (Scardinius erythrophthalmus) in Anzali Lagoon, Iran
In this study, catch per unit effort (CPUE) of three different traps were subjected to a comparison being used for catching the common rudd (Scardinius erythrophthalmus) in the Anzali Lagoon, Iran. The capture efficiencies and the catch rates of the cylindrical pot, the opera house trap, and the hokkaido pot were compared during 2017. The results showed significant differences among the cylindrical pot, opera house traps, and Hokkaido pot. The Hokkaido pot yielded similar performances in stations 2 and 3; however, it differed in station 1. The opera house trap produced different performances in all three stations (P < 0.05), while for the cylindrical pot, the performance was similar in all the three stations (P > 0.05). In conclusion, the opera house trap proved its superior efficiency and is therefore recommended to be used for catching the common rudd in the Anzali Lagoon.
https://ejabf.journals.ekb.eg/article_211510_828d43d0817af5a152d5c694a15bf5c9.pdf
2021-12-01
259
268
10.21608/ejabf.2021.211510
CPUE
Scardinius erythrophthalmus
Traps
Iran
Mehrnoush
Aminisarteshnizi
1
AUTHOR
ORIGINAL_ARTICLE
Checklist of Phytoplankton in the Halda River, Chattogram, Bangladesh
Halda River is a renowned natural spawning ground of major carps due to the unique physicochemical and biological properties of its water. The productivity of the Halda ecosystem depends mainly on plankton diversity. A 2- year- study was conducted (Jan. 2017- Dec. 2018) to identify the phytoplankton community of the Halda River. A total of 74 species of phytoplankton were recorded, which represent 47 genera and belong to 8 classes. The dominant class of phytoplankton was 28 species of Bacillariophyceae (37.84%) followed by 14 species of Zygnematophyceae (18.92%), 8 species of Chlorophyceae (10.81%), 10 species of Cyanophyceae (13.51%), 9 species of Euglenophyceae (12.16%), 3 species of Dinophyceae (4.05%), 1 species of Ulvophyceae (1.35%), and 1 species of Trebouxiophyceae (1.35%). Thus, the River Halda is a productive water body with diversified groups of phytoplankton.
https://ejabf.journals.ekb.eg/article_211516_dab1dd14bf0ce20cfcfef3881898ea90.pdf
2021-12-01
285
296
10.21608/ejabf.2021.211516
Halda River
phytoplankton
Checklist
Chattogram
Bangladesh
Md. Safiqul
Islam et al.
1
AUTHOR
ORIGINAL_ARTICLE
Genotypic characterization of some dermotropic and systemic bacterial pathogens affecting two commercial Red Sea fishes
The genotypic characterization of some bacterial pathogens that were incriminated in disease outbreaks among Haffara seabream “Rhabdosargus haffara” and marbled spine foot “Siganus rivulatus” was investigated in full through the current study. A total of 250 fish samples (125 of each species) were collected along the Red Sea coasts of Hurghada City, Egypt. Fish samples were inspected for clinical signs, post-mortem changes, and bacteriological examination. The investigated fishes displayed septicemic signs and external skin lesions characteristic of streptococcosis and tenacibaculosis. Enterococcus spp., Streptococcus spp., and Flavobacterium spp. were isolated from moribund fishes using selective media. These isolates were phenotypically and genetically identified and characterized. The identities of bacterial isolates were confirmed as Enterococcus fecalis, Streptococcus iniae, Enterobacter cloacae, and Tenacibaculum maritimum based on sequencing the 16S rRNA gene. Enterococcus fecalis was the most common pathogen isolated from S. rivulatus and R. haffara and accounted for 46.8% and 47.8% of the total isolates, respectively. Accordingly, the present study proved that Enterocoocus spp., Streptococcus spp., and T. maritimum are important pathogenic bacteria incriminated in wild fish outbreaks in the Red Sea in Egypt. These findings proved the importance of regular and permanent bacteriological examination of wild fish to overcome fish mortalities, which lead to economic losses. Finally, sequencing and phylogenetic relationship techniques proved their usefulness as an ideal assay to develop a reliable, accurate, and rapid detection method for bacterial pathogens in the aquatic environment.
https://ejabf.journals.ekb.eg/article_211886_913403cb2e3a3abe91ec0a4d5fd3efd9.pdf
2021-12-01
297
312
10.21608/ejabf.2021.211886
E. faecalis
E. cloacae
S. iniae
T. maritimum
Red Sea fishes
Phylogenetic analysis
Awad
A. Abdelbaky et al.
1
AUTHOR
ORIGINAL_ARTICLE
Temporal abundance and distribution of Octopus vulgaris (Cuvier, 1797) in the southern Atlantic waters of Morocco.
A study on the presence of Octopus vulgaris (Cuvier, 1797) in the southern Atlantic coastal waters of Morocco was carried out using data collected by boarding a cephalopod offshore trawler operating in this area by calculating the catch per unit effort (CPUE). The study showed a remarkable abundance of young Octopus individuals in terms of catches compared to large individuals over the entire study period, whether day or night, with lower yields during the nights. Winter trips produced the highest yields. The first days of resumption of fishing, (after a closed season) relating to each trip, showed very large quantities of catch except for the 2016 summer trip. Yields between the 2016 and 2017 summer trips remain relatively constant, while those of the winter trip of 2017/2018 experienced a very significant fall, with a quota achievement rate not reaching 49% compared to 81% achieved during the 2016/2017 winter trip. The results obtained by this study concluded that such management of Octopus vulgaris requires first and foremost good control of its temporal distribution based on the knowledge of the biological and physical phenomena, which interact and govern the abundance and the fluctuations of the stocks of this species.
https://ejabf.journals.ekb.eg/article_212488_ab964548303db7ca8ad75b5ff9468356.pdf
2021-12-01
313
326
10.21608/ejabf.2021.212488
Abundance
CPUE
Distribution
Octopus vulgaris
Recruitment
Trawler
Brahim
Oubahaouali et al.
1
AUTHOR
ORIGINAL_ARTICLE
Acanthamoeba genotypes and Vermamoeba vermiformis in drinking water treatment facilities
Free-living amoebae species, such as Acanthamoeba and Vermamoeba vermiformis are found worldwide and cause severe infections in humans. In the present study, inlet and outlet water samples (n = 96) were collected from conventional and compact drinking water treatment facilities (DWTF), concentrated through nitrocellulose membrane filters (0.45µm pore size), and cultured on non-nutrient agar covered with dead Escherichia coli. The morphologically positive Acanthamoeba and Vermamoeba isolates were subjected to molecular identification and 19 morphologically different Acanthamoeba and two Vermamoeba isolates were genotyped for further confirmation. The results revealed that the predominance free-living amoebae species in surface water samples were belonging to Acanthamoeba (68.8%). All morphologically positive samples for Acanthamoeba proved to be positive by PCR. The conventional DWTF showed better results (66.7%) for removing Acanthamoeba and Vermamoeba vermiformis than the compact DWTF (50%). At the sequence level, three Acanthamoeba genotypes (T3, T4, and T15) and one Vermamoeba species (i.e., Vermamoeba vermiformis) were obtained. In conclusion, conventional DWTF was more effective than compact DWTF in removing Acanthamoeba. The presence of viable Acanthamoeba strains especially the pathogenic types (e.g., Acanthamoeba T4) in outlet water could cause health hazards to consumers.
https://ejabf.journals.ekb.eg/article_212783_17b934ed36607e41b901e5a24886ebe6.pdf
2021-12-01
327
341
10.21608/ejabf.2021.212783
Water treatment
Escherichia coli
Acanthamoeba genotypes
Vermamoeba vermiformis
Mohamed
A. Marouf et al.
1
AUTHOR
ORIGINAL_ARTICLE
Suppressive of hepatotoxicity caused by lead and cadmium in the sea bass Dicentrarchus labrax by using an algal mixture of Spirulina platensis and Chlorella vulgaris
Heavy Metals as Cadmium (Cd) and lead (Pb) are toxic and harmful to humans and animals. The present study aimed to investigate the protective effect of three concentrations of an algal mixture of Spirulina platensis and Chlorella vulgaris in chelating of the mixture of cadmium chloride and lead nitrate in the liver of seabass (Dicentrarchus labrax). Na+/K+-ATPase, the total cytochrome P450 (CYP 450), antioxidant enzymes Superoxide dismutase SOD, Catalase CAT, Glutathione peroxidase Gpx, and non-enzymatic antioxidant metallothionein MTs were measured as biomarkers. n the experimental diets, the first group was fed with a basal diet and lived in seawater (control 1); in other groups, heavy metals (0.003 mg/l of CdCl2 + 0.003 mg/l Pb(NO3)2 were added and fed a basal diet (control 2), or 3% of diet supplemented with the algal mixture of Spirulina and Chlorella in the ratio (1: 1) (diet 1), 5% of a diet with the algal mix (diet 2), and 7% of a diet with the algal mixture (diet 3). Fish were fed 5% of the average body weight three times a day. There is a significant decrease in the activity of Na+/K+-ATPase (P <0.05) between (control 1) and the other groups. The groups of diets 2 and 3 showed significant improvements in the value of Na+/K+-ATPase compared to the control “1” group. The CYP is highly induced in the control “2” compared to the control “1” or other groups. Diet “3” shows a minimum significance of CYP concentration than the control “2”. There is a significant increase in SOD and Gpx activities in the liver of treated fishes (diets 2 and 3) compared to the control “2”. The results reveal that the best supplement of the algal mixture appears in the concentration of 7% (diet 3). This concentration repairs the ionic disturbance and oxidative stress of lead and cadmium toxicity and increases the antioxidant activities responsible for reactive oxygen species ROS scavenging
https://ejabf.journals.ekb.eg/article_212893_d97fd3864d4976bef45577281ca1ecba.pdf
2021-12-01
343
360
10.21608/ejabf.2021.212893
Spirulina platensis, Chlorella vulgaris
Antioxidant enzymes SOD
catalase
GPx
Non-enzymatic antioxidant, metallothionein
Soha
S. Hasanein
1
AUTHOR
Amr
M. Helal
2
AUTHOR
ORIGINAL_ARTICLE
Monitoring the relationship between alteration in environmental factors and nutritive value of Rissoides desmaresti (Crustacea)
Rissoides desmaresti shrimp is a good source of a high nutritional value, which makes it a very healthy food choice for humans. The relationship between the environmental factors (temperature, salinity, pH value, and dissolved oxygen) and the nutritive values of Rissoides desmaresti (Crustacean- Stomatopoda) was addressed and the factors were seasonally measured in the current study. Concurrently, the nutritive values (crude protein, lipid, carbohydrate, calorific value, moisture, and ash) in the muscle tissue of Rissoides desmaresti were seasonally analyzed. The statistical analysis showed that the values of the correlation coefficient for different biochemical composition parameters with the ecological factors ranged between very strong positive correlation and very strong negative correlation. The relationships were different; the most influential detected factor was salinity, followed by temperature, dissolved oxygen, and pH. Remarkably, these constituents are affected by the alteration in ecological factors, forming an indicative indicator to know how far the organism is affected by those factors, and detect their permanent change associated with the climatic changes.
https://ejabf.journals.ekb.eg/article_213134_daf0bce9059f23238071997ae9ff8245.pdf
2021-12-01
361
375
10.21608/ejabf.2021.213134
Mediterranean Sea
Environmental factors
Rissoides desmaresti
Crustacea
Nutrative value
Benthos
Amr
M. Nasef
1
AUTHOR
ORIGINAL_ARTICLE
Dynamic of microcystin-LR-producing cyanobacteria in a drinking water supply: Guenitra dam (North-East of Algeria)
The presence of microcystins (MCs) in waters exclusively intended for drinking water production is a major problem for both ecosystems and public health. The current study aimed to identify the environmental factors that explain the spatial and temporal variations in the abundance of cyanobacteria and the concentration of microcystins in the Guenitra Dam, a Mediterranean water body used for drinking water production, irrigation supplies, and fisheries. The Guenitra Dam waters are mesotrophic to eutrophic; they shelter nine genera of cyanobacteria in which Microcystis flosaquae is dominant in the frequency of occurrence and densities. Cyanobacterial densities in the Guenitra Dam exceed the level of vigilance in January; alert level 1 was shown during the rest of the year and alert level 2 was in November, with a peak registration of more than 189 million cells / mL. The highest cell densities were found in surface waters and decreased with depth. In autumn, more than 99% of the overall cyanobacteria density was detected. The MC-LR contents did not exceed 0.5 µg.L-1 except in November (1.02 µg.L-1 in St5) and December (1.5 µg.L-1 in St4). From January to September, the levels did not surpass 0.22 µg.L-1. Statistical analysis revealed the existence of very highly significant (p <0.0001) positive correlation of M. flosaquae with microcystins (MC-LR) and highly significant (p <0.001) of M. flosaquae with NH4+. During the bloom found in November, the presence of MC-LR in the drinking water was recorded, with a concentration of 0.57 µg.L-1, which is clearly higher than that allowed (0.1 µg.L-1) by the WHO. The presence of MC-LR in the drinking water is indicative of a failure in the water treatment process. The presence of cyanobacteria and cyanotoxins in raw and drinking waters of the Guenitra reservoir involves regular monitoring of the cyanobacterial communities and cyanotoxins in raw water.
https://ejabf.journals.ekb.eg/article_213138_4374aedd54e20f09112ba181da1a6de2.pdf
2021-12-01
377
395
10.21608/ejabf.2021.213138
Cyanobacterial blooms, Microcystis, Microcystine-LR,
Drinking water, Guenitra da
Khedidja
Boufligha et al.
1
AUTHOR
ORIGINAL_ARTICLE
Reproductive Biology of Charybdis hellerii in Lasongko and Kendari Bays, Southeast Sulawesi, Indonesia
Limited Data have been found on the reproductive biology of Charybdis hellerii (A. Milne-Edwards, 1867) in Indonesia. To fill this gap, the current study aimed to analyze various aspects of the reproductive biology of C. helleri, male and female, in Lasongko and Kendari Bays. Using traps, samples of crab species were monthly collected (from March- November 2019) with the help of blue swimming crab fishermen. Results showed that the total sex ratio of C. hellerii in Lasongko and Kendari Bays were 1: 0.48 and 1: 0.57, respectively. However, the temporally sex ratio of the crabs varied. In Lasongko Bay, male gonads of C. hellerii were majorly immature, while those of the females and ovigerous females were mature. Meanwhile, in Kendari Bay, all three types were predominantly immature, and they were all temporally varied. The first sizes sexual maturity of the male and female C. hellerii in Lasongko Bay were 60.04 mmCW and 53.12 mmCW, respectively, while those of Kendari Bay were 60.23 mm CW and 53.24 mmCW, respectively. The spawning season of this crab species tends to occur throughout the year. Therefore, the data obtained in this study can be used for the management of C. hellerii in Lasongko and Kendari Bays and Southeast Sulawesi waters.
https://ejabf.journals.ekb.eg/article_213140_44e650ed76d1bb30fd080ea4e0f37521.pdf
2021-12-01
397
410
10.21608/ejabf.2021.213140
Crustaceans
Gonad development
sex ratio
sexual maturity
Spawning season
Abdul
Hamid et al.
1
AUTHOR
ORIGINAL_ARTICLE
Salinity variation as a limiting environmental factor and its effect on biochemistry and protein quality of Tilapia zillii
Fish differ in their ability to adapt to the environment and vary in their nutritional and economic values. Therefore, this study was conducted to clarify the dynamics of the biochemical composition of the Tilapia zillii, and detect the impact of salinity, as a limiting environmental factor, on the organism’s potential to adapt to the environment. In addition, the assessment of the feasibility of transport and farming operations with their financial returns was also considered. Hence, the green tilapia, Tilapia zillii that lives in different aquatic environments (fresh: <0.05 ‰ Ismailia Canal - brackish 20:28 ‰ Altemsah Lake - salty 30 - ‰ eastern Altemsah Lake) was subjected to a quantitative/ qualitative study. The approximate composition and biochemical components were seasonally analyzed in the muscle tissue of this species representing different environments. The amount of crude protein, fat, carbohydrates, calorific value, moisture and ash were also measured.
The quantitative biochemical analyses showed statistically significant differences (P<0.05) among the samples extracted from the environmental areas of different salinity levels. Similar results were detected in the values of protein, fat, carbohydrates, calories, water, and ash content. On applying the protein electrophoresis technique, the qualitative analysis showed no large qualitative variation among the studied samples.
https://ejabf.journals.ekb.eg/article_213188_bea6046ec3e9ebf6f859b55ed1395286.pdf
2021-12-01
411
431
10.21608/ejabf.2021.213188
environment
Tilapia zillii
salinity
Limiting factor
Lake Timsah
biochemical
composition
Amr
M. Nasef
1
AUTHOR
ORIGINAL_ARTICLE
The potential effect of Trivir® (10% carvacrol) as an alternative antibacterial agent for controlling bacterial infections in the African catfish (Clarias gariepinus).
Production and control of fish health safely together with living in harmony with nature, natural substances considered as an important area for future developments in aquaculture. In this respect, the current study aimed to investigate the antibacterial activities of Trivir®(10% carvacrol), one of the major essential oils of oregano, against some fish pathogenic bacteria isolated from diseased catfish (C. gariepinus). Trivir®solution was designated to be used as a broad-spectrum disinfectant for aquaculture according to the manufacture instructions. The antibacterial effects of the Trivir®were tested on clinical isolates of Aeromonas hydrophila, Enterococcus faecalis and Shewanella putrificans. The minimum inhibitory concentrations (MICs) of carvacrol against Aeromonas hydrophila were estimated as 62 μg/ ml, 125μg/ml for Shewanella putrificans, and 250μg/ml for Enterococcus faecalis. At all tested levels, Trivir®showed no bactericidal activities against all tested clinical bacterial isolates. C. gariepinus exposed to 32, 62, and 125 μg/ml of Trivir®showed survival rates of 100% at all exposure times tested. In the contrast, Trivir® showed its toxic effects at concentrations of 1000, 500, 250 μg/ml after exposure times of 15, 30, and 60 min causing 100% mortalities in catfish. In conclusion, carvacrol can be considered as an effective alternative for antibiotics usage in aquaculture with ultimate competent health and a safe environment.
https://ejabf.journals.ekb.eg/article_213605_4bf4872a9bc5d747af050f7afd9ef4e0.pdf
2021-12-01
433
443
10.21608/ejabf.2021.213605
African catfish
Clarias gariepinus
Aeromonas hydrophila
Enterococcus faecalis
Shewanella putrificans
Mortada
M. A. Hussein et al.
1
AUTHOR
ORIGINAL_ARTICLE
Seasonal variations in the abundance and diversity of zooplankton community inhabiting River Nile and its branches at Qena governorate, Upper Egypt.
In the present study, the diversity and seasonal variation of the freshwater zooplankton were studied throughout a period of one year (September 2020 to August 2021). Sampling collections were monthly carried out from fifteen sites representing 7 cities located north, and south to Qena city from the River Nile and its branches (26°9'18.22"N and a longitude of 32°42'57.64"E). Physiochemical factors of water of the different collecting sites were measured and analysed using One-way Analysis of variance (ANOVA), and 195056 individuals were collected. Shannon-Weiner diversity, Equitability and Margalef’s indices were used to determine zooplankton composition. The results revealed that there were 48 taxonomic units dominated by cladocerans (87%, 23 taxa) followed by copepods (11.74%, 12 taxa), rotifers (1.01%, 8 taxa), and ostracods (0.24%, 3 taxa). The most common species of Cladocera was Chydorus sphaericus representing 62.95 %; while the most common of Copepoda was Messocyclops ogunnus representing 34.71%. The most common species of Rotifera was Lecane lune representing 34.80 %; whereas, the most common of Ostracoda was Cypridopsis vidua representing 96.22 %. Both zooplankton communities and populations of Cladocera showed higher density during the rainy season. Investigation on the physiochemical parameters showed that pH, turbidity, and dissolved oxygen all recorded maximum values in the autumn season. Furthermore, both the total dissolved solids and conductivity recorded maximum values in the winter season. Total abundance of zooplankton showed a positive relationship with Taxa richness, Shannon-Weiner diversity, and Margalef’s index and Equitability. They showed their peaks during the winter season, while the evenness index increased in the dry season.
https://ejabf.journals.ekb.eg/article_213776_d0d54faae16543053ac42c9316a21d9d.pdf
2021-12-01
445
466
10.21608/ejabf.2021.213776
Cladocera
copepoda
Ostracoda
Rotifera
composition
- Physicochemical measurements
Wafaa
A. Mohammad et al.
1
AUTHOR
ORIGINAL_ARTICLE
Three decades of remote sensing habitat mapping, along the Egyptian Coast of Aqaba Gulf, Red Sea
Over the last three decades, the Egyptian Red Sea shorelines had seen significant growth. In this short period, the Gulf of Aqaba's coastline has been turned into a lengthy belt of tourism settlements and hotels. Due to scarcity of information about this area, herein, a first-time ultimate remote sensing time-series change detection in the region. Landsat satellite data collected over the Gulf of Aqaba during the period from 1985 to 2020 and analysed to estimate urban expansion and shoreline changes in the study area, in addition, from 1995 to 2020 to monitor changes in the coral reef and benthic habitats coverage over time. Landsat 5-TM, Landsat 7-ETM+, and Landsat 8-OLI imagery were used to create a time series of satellite observations. The results showed that the urban development had a large scale increase in the past three decades by about 4.1 km2 and 2.8 km2 at Dahab and Nuweiba’a sectors respectively. While shoreline changed on a smaller scale than the urban development in a regular way without harm to natural resources. Changing – urban and shoreline – came along with tourism intensity. Concerning key environmental factors results of Time Series Analyses showed high variance in time especially during the period from 1993 to 2003, while the sea surface temperature had a stable trend. Benthic habitat mapping at Dahab showed stability of the coverage area of the most benthic habitats except for an increase of both corals and macroalgae between 1995 and 2005, whereas there is a fluctuation in coral coverage at Nuweiba’a area over time.
https://ejabf.journals.ekb.eg/article_214042_bb7275db59b53070e42d7593358a6223.pdf
2021-12-01
467
487
10.21608/ejabf.2021.214042
Change Detection
Remote Sensing
Habitat mapping
tourism
Overfishing
Dahab
Nuweiba’a
Red Sea
Egypt
Kareem
F. Darweesh et al.
1
AUTHOR
ORIGINAL_ARTICLE
Effect of different salinity levels on egg hatching and survival rate of different metamorphosis larval stages of Kuruma shrimp, Penaeus japonicus (Bate, 1888)
The effect of six different salinity levels was studied on egg hatching percentage and survival rate of different larval stages of the Kuruma shrimp, Penaeus japonica. Eggs of the Kuruma shrimp and different larval stages included nauplius, zoea, mysis, and postlarvae were stocked at experimental glass vessels (2 L) in replicates for each treatment at a density of 50 per replicate. The different stages were evaluated under different water salinity levels included 20, 25, 28, 30, 35 and 38 ppt. All vessels were supplied with continuous aeration. Kuruma shrimp stages were fed during the experimental period with micro-algae, rotifers, and Artemia on a live food program. Some physico-chemical parameters included temperature, salinity, pH, Turbidity, TAN, NH3, and DO were determined during the experimental period (23 days). The data of the eggs hatching percentage and survival rate of the different larval stages of Kuruma shrimp reared in different tested salinity levels showed that all stages reared in 20 ‰ salinity level gave the lowest survival rate in compared to those reared in 38 ‰ and the other tested salinity levels without significant differences (P < 0.05). Increasing the water salinity levels in the culture water over 20 ‰ resulted in an improvement in survival rate in all tested larval stages especially on 38 ‰, it was the best survival rate between all tested salinity levels in the Nauplius stages (N1- N6), Zoea stages (Z1- Z3) with significantly differences (P < 0.05). Also, the best survival rate was in 38‰ with significant differences (P < 0.05) for Mysis stages (M1- M3), Data showed that the highest tested salinity level (38 ‰) gave the higher survival rate to post larvae of the kuruma shrimp included 94%, 85%, and 80%, for PL1, PL6, and PL12, respectively. The results showed that the survival rate for all larval stages was obtained in 38 ‰ salinity levels. Therefore, it could be recommended for applying and extending out these results under Egyptian conditions.
https://ejabf.journals.ekb.eg/article_214164_0de79c604bcdc52e0968563969b53d92.pdf
2021-12-01
489
502
10.21608/ejabf.2021.214164
Salinity levels
Nauplius
Mysis
Post larvae
Kuruma shrimp
Penaeus japonicas
El-Sayed
Hemdan Eissa et al.
1
AUTHOR
ORIGINAL_ARTICLE
Effect of diel variation on trawl fishery-catch rates in the Gulf of Suez, Red Sea, Egypt
Two experimental trawl surveys were conducted in the Gulf of Suez during[m1] April (spring) and November (autumn) 2014. The current study addressed the effect of the diurnal variables (day and night) on the catch rates of three fish species (lizard fish Saurida undosquamis, horse mackerel Trachurus indicus, threadfin bream Nemipterus japonicus), two cephalopods (cuttlefish Sepia sp, Indian squid Loligo duvauceli) and two crustaceans (Crab Portunus pelagicus and shrimp < em> Penaeus sp.). In both surveys, the highest catch was caught just after dusk during the daytime, while during the night, it was recorded in the middle of the night. In spring, day and night mean catch rates were not significantly different (P˃0.01) for all species. While in autumn, the rates of Trachurus indicus, Loligo duvauceli, and Penaeus sp. were significantly different (P ˂ 0.01 and T values were 2.80, 3.28 and 2.34, respectively). In addition, those of Saurida undosquamis, Nemipterus japonicus, Sepia sp., and Portunus pelagicus were not significantly different (P˃0.01). The results of the study revealed that both the early morning and the late evening are the best times for fishing.
[m1]
https://ejabf.journals.ekb.eg/article_215046_dc05b3651dfddc69029b40b467b144b7.pdf
2021-12-01
503
512
10.21608/ejabf.2021.215046
catch rate
Diurnal variation
Trawl fishery
Gulf of Suez
El-Azab
E. Badr El-Bokhty et al.
1
AUTHOR
ORIGINAL_ARTICLE
Effects of Feeding Frequency on Growth Performance of the Juvenile Bagrid Catfish, Chrysichthys nigrodigitatus
This study was presented to evaluate the effects of feeding frequency on growth performance, feed utilization, proximate composition and water quality parameters of Bagrid catfish (Chrysichthys nigrodigitatus). Four groups of fishes were fed at four different feeding frequencies; once, twice, thrice and four times per day (Trt1, Trt2, Trt3& Trt4, respectively).. C. nigrodigitatus, with an initial weight of 24.80 ± 0.99 g, were stocked at 30 fishes per concrete tanks, with dimensions of 3 m×1 m× 1 m and fed to apparent satiation in accordance to the designated feeding frequencies. Fish fed Trt2 recorded ammonia content of 0.26 ± 0.04 and was significantly lower than fish fed Trt4 (P<0.05). However, no significant difference was detected in values of temperature, pH, nitrite, and nitrate. The maximum final weight (67.20 ± 2.07) and specific growth rate (4.13 ± 0.03) were observed in fish fed Trt2 and were significantly higher than all other groups (P<0.05). A significant difference was recorded among treatments with respect to protein efficiency ratio, feed intake and feed conversion ratio. The protein efficiency ratio was higher in fish fed Trt 2 (1.72 ± 0.08) and was significantly higher than fish fed Trt3 (0.87 ± 0.06) and Trt4 (0.92 ± 0.06). Fish fed Trt2 consumed more feed (42.01 ± 4.17) and was significantly higher than all other groups. In conclusion, the optimum feeding frequency of Bagrid catfish (Chrysichthys nigrodigitatus) was proved to be two times a day with equal intervals.
https://ejabf.journals.ekb.eg/article_215164_e7958c6df5cbb567d37ffc5e404b479d.pdf
2021-12-01
513
527
10.21608/ejabf.2021.215164
proximate composition
water quality
Feed conversion ratio
feed utilization
Christian
Larbi Ayisi et al.
1
AUTHOR
ORIGINAL_ARTICLE
Seasonal Variations in the Proximate Composition of the Wild-Captured and Cultured Pangas
The current study was conducted to compare the nutritional values of the wild-captured Pangasianodon hypophthalmus and those of the farm-cultured Pangasius pangasius, pangas. Fish samples were collected from the Meghna River Estuary (from the river and a fish farm) from October 2018 till January 2020 with respect to three seasons. Moisture, protein, lipid, carbohydrate, ash, and fiber contents were estimated. according to AOAC 2000 methods data obtained were analyzed using one- and two-way ANOVA. The means of values were compared using Duncan’s test at (p < 0.05). Proximate composition was affected by season and fish environment. Protein content was significantly higher in winter for both wild and farmed fish. Ash, fiber, and carbohydrate contents were higher in winter than in other seasons in both wild and farmed fish. Protein and carbohydrate contents were higher in wild pangas than in farmed fish in all seasons. The ash content of pangas was higher in the wild fish in autumn and winter, while in the farmed fish, the ash content was higher in summer. It was concluded that wild pangas contain higher levels of nutrients than farmed pangas. This variation is due to the feeding regime, feed type, environmental factors, and water depth. However, both wild and farmed pangas are rich in essential nutrients, so both may play a significant role in contributing to the nutritional demands of the population in Bangladesh.
https://ejabf.journals.ekb.eg/article_215172_d123d461e4ef8d1bce9f57d228920066.pdf
2021-12-01
529
540
10.21608/ejabf.2021.215172
Seasonal variation
nutritional composition
Wild-captured pangas
Farm-cultured pangas
protein
Md. Refat
Jahan Rakib et al.
1
AUTHOR