The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
INJURIES IN KIDNEY TISSUE OF THE MUGIL FISH LIZA RAMADA AS A BIOMARKER FOR ENVIRONMENTAL POLLUTION IN THE LAKE MANZALAH
1
24
EN
Shadia
Kadry
Department of Zoology, Girls College for Arts, Science and
Education.
Amal
Yacoub
National Institute of Oceanography and Fisheries.
Talaat
Siliem2
National Institute of Oceanography and Fisheries
Dalia
Mabrouk
National Institute of Oceanography and Fisheries
10.21608/ejabf.2003.1763
This study deals with the effect of aquatic environmental pollution of Lake Manzalah on Lizaramada. The fish and water samples were collected seasonally for a year from Autumn 2000 to Summer 2001 from the selected stations near Boughaz El-Gamil. Other water samples were collected from 12 different stations in other locations. The study included heavy metal analysis of the water lake and histopathological changes in the kidneys of the same fish. The investigation revealed that the high values of heavy metals (Fe, Mn, Cu, Zn, Pb and Cd) encountered during the different seasons in lake Manzalah induced toxic effects on Lizaramada kidneys which may decrease the productivity of this Mugil species. So, it is recommended to try to protect this fish from the destruction by drainage water loaded with agricultural and industrial pollutants as well as sewage.
Lake Manzalah,pollution,fish,kidney
https://ejabf.journals.ekb.eg/article_1763.html
https://ejabf.journals.ekb.eg/article_1763_caf73fa3e773ebe1eb388c3274ba2017.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
PHYTOPLANKTON STANDING CROP AND SPECIES DIVERSTIY IN RELATION TO SOME WATER CHARACTERISTICS OF SUEZ BAY (RED SEA), EGYPT.
25
48
EN
Mohamed
Nassar
National Institute of Oceanography and Fisheries, Suez and Aqaba Gulfs Branch, Egypt.
Mohamed
Hamed
National Institute of Oceanography and Fisheries, Suez and Aqaba Gulfs Branch, Egypt.
10.21608/ejabf.2003.1764
Phytoplankton standing crop and species composition in Suez Bay were studied and discussed in relation to the environmental physico-chemical parameters during 2002-2003. A total of 80 species and varieties were recorded and identified at the selected stations of the bay'/Of them 47 species and 29 genera of diatoms; 19 species and 11 genera of dinoflagellates; seven species of cyanophytes within four genera; six species of chlorophytes among four genera and one species of chrysophytes. Two main phytoplankton peaks were recorded during spring and autumn seasons (average of 15,676 and 15,376 unit.!/1 respectively). The diatom species responsible of these peaks were, Nitzschia pungens var. atlantica, Asierionellajapomca, Skeletonema costatum, Chaetoceros decipiens and Gyrosigma attenuatitm. The species diversity showed a minimum value at the sewage treating company (ABB station) ranging from 2.17-3.36 nats. While, the highest diversity values were recorded at the unpolluted station, Aiyoon Mousa (VI) and varied from 2.74-3.61 nats. The results revealed regional and seasonal inverse correlation between diversity and phytoplankton standing crop in Suez Bay and it is regarded as a pollution habitat.The results of N:P ratio indicated that Suez Bay is generally P-limited, mainly due to the high load of nitrogenous compounds specially ammonia, which formed about 60.7:1 % of the total inorganic nitrogen, followed by nitrate (33.7 %) and:nitrite (5.57 %). Dissolved inorganic phosphate recorded with annual average of 0.98 pmoIX"1. Generally, the level of nutrient salts indicated that Suez Bay is in the eutrophic state.
phytoplankton,Nutrients,Suez Bay
https://ejabf.journals.ekb.eg/article_1764.html
https://ejabf.journals.ekb.eg/article_1764_587238be368dbead0830f097b42d7f90.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
EXPERIMENTAL TOXICITY OF CHROMIUM TO TWO FRESHWATER CRUSTACEANS; DAPHNIA MAGNA AND MACRQBRACHIUM ROSENBERGII
49
70
EN
Mahasse
Ghazy
Water Pollution Control Division, National Research Center, Cairo, Egypt
Madlen
Habashy
National Institute of Oceanography and Fisheries, Fish Research Station, EI-Qanater-El-Khayriya, Egypt
10.21608/ejabf.2003.1767
The analysis of the potential toxicity of chromium, was conducted on two aquatic model systems, namely the cladoceran Daphnia magna and the decapod Macrobrachium rosenbergii. Chromium was chosen since human activity has led to a conspicuous increase of this metal in the environment. The toxicity of chromium to Daphnia magna was evaluated on the basis of a 48-hr 50% lethal concentration (LC50)3 a 3-week LC50 and a 16% decrease in the number of bom young (reproductive impairment). The daphnids were exposed for concentrations ranging from 2 to 30 \ig Cr/L from which 48 hr- LC50 was calculated both in absence and presence of EDTA, a chelating agent to be 8 and 27 |ig Cr /L, respectively. In the static- renewal systems, daphnids were exposed to sublethal doses (13, 16, 18,22 and 23 jag Cr/L) equivalent to LC10, LC20, LC25, LC35 and LC40, respectively, as deduced from the regression line for chromium toxicity for 48 hr. in the static system in presence of EDTA. The 3-week 16% reproductive impairment concentration for the metal ions was 17fig- Cr/L. At metal concentrations permitting survival but impairing reproduction (sublethal concentration), daphnids body length and weight were less than those of control animals. The concentration causing 50 % reproductive impairment was more or less the same as the 48-hr LC50 (in presence of EDTA), being 26 and 27 M-g Cr/L respectively. The 21-day LC50 was 16. 5 ngCr/L. The time of onset of reproduction ranged from 6 days in the control to 14 days in the highest concentration. The acute toxicity of chromium to the freshwater prawn Macrobrachium rosenbergii revealed that the 48-hr LC50 was 425 jigCr/L. Prawn juveniles were exposed in static-renewal systems for 45 days, to sublethal doses (210, 300, 325 and 375 ngCr/L) equivalent to LC10, LC25, LC30 and LC40 respectively, as deduced from the regression line for chromium toxicity for 48 hr in the static system. The results showed that juvenile prawn of initial weight 0.255±0.097 g, in higher concentration (375 \i g Cr / L), had given a significant decrease (PO.05) from the control in final mean weight, weight gain, % weight gain, specific growth rate and survival, represented by 0.270 g, 0.015 g, 1.928, 0.127 and 33.3 % , respectively. Also prawn in different concentrations of chromium recorded the highest food conversion ratio represented by 3.76,6.39, 8.1 and 8.7, respectively, Amounts of total protein and lipids of both daphnids and prawns varied with the different concentrations. This study indicated that Daphnia magna was more sensitive to chromium than Macrobrachium rosenbergii and that bioassays with these two organisms are useful to assess the toxic potential of aquatic pollutants,
Chromium,Daphnia magna,Macrobrachium rosenbergii,toxicity,Survival,growth rate,reproductive impairment
https://ejabf.journals.ekb.eg/article_1767.html
https://ejabf.journals.ekb.eg/article_1767_579910df3b305de17fcee66355a4d559.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
POPULATION DYNAMICS OF THE BIGEYE SNAPPER LUTJANUS LINEOLATUS, RUPPELL, 1829 (FAMILY: LUTJAN1DAE) FROM THE GULF OF SUEZ, EGYPT.
71
85
EN
Sahar
Mehanna
National Institute of Oceanography and Fisheries, Suez, Egypt
10.21608/ejabf.2003.1768
Age, growth, mortality, relative yield per recruit and relative biomass per recruit of Lutjanus lineolatus collected from the Gulf of Suez during the period from October 2001 until May 2002 have been estimated. Age was determined from otolith's reading and the results showed that the maximum life span of L lineolatus is 4 years. The growth parameters were estimated as K = 0.40 year"1 and L« = 24.45 cm. The annual rates of total, natural and fishing mortality were calculated as 1.37, 0.31 and 1.06 year"1 respectively. Exploitation rate E was estimated as 0.77. The relative yield per recruit analysis showed that the stock of L. lineolatus is overexploited, To maintain this living marine resource, precautionary management measures including decrease of the present fishing pressure and increase of the length at first capture to be about 13.5 cm should be applied.
Lutjanus lineolatus^ age and growth,mortality and exploitation rates,relative yield per recruit,relative biomass per recruit
https://ejabf.journals.ekb.eg/article_1768.html
https://ejabf.journals.ekb.eg/article_1768_d0b5d7e5296f3d971e72d3c9e83ba037.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
MIRACIDIOPHAGIC AND CERCARIOPHAGIC ACTIVITY OF THE FISH GAMBVSIA AFFINIS AND OREOCHROMIS NILOTICUS AND THEIR EFFECT ON THE INFECTION OF BIOMPHALARIA ALEXANDRJNA BY SCHISTOSOMA MANSONI MIRACIDIA
87
98
EN
Nahed
Ismail
Department of Environmental and Medical Malacology, Theodor Bilharz Research Institute
10.21608/ejabf.2003.1769
Miracidiophagic and cercariophagic activity of two fish species namely Gambusia affinis and Oreochromis niloticus and their possible role in controlling the infection of Biomphalaria alexandrina with Schistosoma mansoni mracidia were studied. The results showed that the infection rates of B. alexandrina exposed for about 3000 miracidia in presence of each fish species were significantly lower than the controls. There was an inverse relation between the number of O. niloticus and the infection rate of B. alexandrina. Conversily, in case of G. affinis, the rate of infection of B, alexandrina was increased by increasing the number of fish added to the same volume of water. The miracidiophagic activity of O. niloticus indicated that the average percentage of miracidia consumed by fish after 60 minutes exposure were 71.05 % and 78.2 % when fish were exposed to approximately 1500 and 3000 miracidia respectively. The cercariophagic activity of G. affinis and O. mlojicits showed that the reduction in the number of cercariae offered to each fish species were significantly higher than the controls. The consumption of cercariae by each fish species was greatly influenced by cercariae concentration; the higher the concentration, the more cercariae consumed by the fish.
fish,Gambusia affinis,Oreochromis niloticus,Biomphalaria alexandrina,schistosmiasis,miracidia,Cercariae,biological control
https://ejabf.journals.ekb.eg/article_1769.html
https://ejabf.journals.ekb.eg/article_1769_03df9818f98841a066c5db79a97f328e.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
HISTOPATHOLOGICAL STUDIES ON SOME ORGANS OF OREOCHROMIS NILOTICUS, TILAPIA ZILLII AND SYNODONTIS SCHALL FROM EL-SALAM CANAL, EGYPT
99
138
EN
Fatma
Mohamed
National Institute of Oceanography and Fisheries, Inland Waters and Aquaculture Branch, Al-Qanater Al-Khairya Fish Research Station,
Cairo, Egypt.
10.21608/ejabf.2003.1770
In the present study, the histological structures of the gills, liver, kidneys and gonads of Oreochromis niloticus, Tilapia zillii and Synodoniis schall from El-Salam canal were studied for a period extending from spring 2000 to winter 2001 (4 successive seasons). Several histopathological changes were observed in the gills, liver, kidneys and gonads of the studied fish during the four seasons.In the gills, proliferative changes in the epithelium of gill filaments and secondary lamellae, degenerative and necrotic changes in gill filaments, separation of the epithelium of the secondary lamellae from the lamellar supporting cells in gill filaments, intravascular haemolysis and dilation in the blood vessels of gill filaments, haemorrhage between gill filaments, edema in secondary lamellae and mucus accumulation between gill filaments were seen.In the liver, vacuoiar degeneration, focal areas of coagulative necrosis, focal areas of necrosis, destruction of hepatoportal blood vessels and haemorrhage between the hepatocytes were observed. Besides, intravascular haemolysis and dilation were seen in hepatic and hepatoportal blood vessels. Also, dilation and congestion were noticed in blood sinusoids.In the kidneys, the histopathological changes included vacuoiar degeneration in the epithelium of renal tubules, focal areas of necrosis between the renal tubules, depletion in the haemopoietic areas, haemolysis between the renal tubules and edema in Bowman's capsules. Moreover, intravascular haemolysis in renal blood vessels and over population of glomeruli were observed.
pollution, histopathology, gills, liver, kidneys, gonads,Oreochromis niloticus, Tilapia zillii, Synodoniis schall, El-Salam Canal
https://ejabf.journals.ekb.eg/article_1770.html
https://ejabf.journals.ekb.eg/article_1770_031b5fc1fb760dbcf5afeba2f47cde44.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
CONCENTRATIONS OF CERTAIN HEAVY METALS IN IMPORTED FROZEN FISH IN EGYPT
139
154
EN
Ahmed
El Nemr
Environmental Division, National Institute of Oceanography and Fisheries, Kayet Bay, Alexandria, Egypt
10.21608/ejabf.2003.1771
Concentrations of nine heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pd and Zn) were determined "in; imported frozen'fish namely Mackerel (Scomber scolnbrus)^ ' Striped red mullet (Mullus surmuletus), Groster argentine {A rgentina silus), Commen pandora (Pagellus erytlvinus) and Atlantic horse mackerel (Trachurus trachurus). The average concentrations of the heavy metals analyzed exhibited the following decreasing order: Fe > Zn > Pb > Co > Cu > Cr > Mn > Ni > Cd. The concentrations of the studied heavy metals in fish tissues were lower than the Effect Range-Low (ERL) for such fish, while gill and liver exhibited elevation over the ERL for Cd only. The metal pollution index (MPI) for most studied fish fluctuated between 0.90 and 4.42 with average 2.18 for wet weight. The ingestion of heavy metals and the calculated lifetime daily intake have been reported and do not represent any actual risk due to the low concentrations of heavy metals in the studied fish tissues. These results suggest that the studied imported frozen fish might be considered as unpolluted with heavy metal.
Imported frozen fish,Heavy metals,pollution,ingestion fish,Hazard index,Egypt
https://ejabf.journals.ekb.eg/article_1771.html
https://ejabf.journals.ekb.eg/article_1771_f09c56fd3f405543fc19d0c6a46aa7b2.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
HEAVY METALS CONCENTRATION IN SOME FISH TISSUES FROM SOUTH MEDITERRANEAN WATERS, EGYPT
155
172
EN
Ahmed
El Nemr
Environmental Division, National Institute of Oceanography and Fisheries, Kayet Bay, Alexandria, Egypt
Amany
El-Sikaily
Environmental Division, National Institute of Oceanography and Fisheries, Kayet Bay, Alexandria, Egypt
Azza
Khaled
Environmental Division, National Institute of Oceanography and Fisheries, Kayet Bay, Alexandria, Egypt
10.21608/ejabf.2003.1772
The concentrations of nine heavy metals (Cd, Co, Cu, Fe, Hg, Mn, Ni, Pd and Zn) were determined in five common fish namely: Sigana-Batata (Siganiis rivulatus), Bouri {Mugil capito\ and Balarnita bed' (Scomber unicolor) from the open sea, facing to Lake Edku, and Bolti Aklidar (Tilapia zillii) and Karmout (Clarias lazera) from Lake Edku. Three metals (Co, Ni and Pd) were not yet detected in the studied fish species during the four seasons. The average concentrations of the other heavy metals analyzed exhibited the following decreasing order: Fe > Zn > Mn >Cd>Cu>Hg. The concentrations of Cu and Zn were lower than the Effect Range-Low (ERL) for all studied fish, while the other metals (Fe, Mn, Cd and Hg) were ranging from over the ERL and under the Effect Range-Median (ERM). These results suggest that the fish collected from open sea and Lake Edku might be considered relatively unpolluted 'with heavy metals. The metal pollution index (MPI) for most studied fish fluctuated between the calculated MPI for ERL and ERM. However, MPI recorded for summer showed the highest value over other seasons in the studied fish samples.
fish,Heavy metals,south Mediterranean,Lake Edku,Egypt
https://ejabf.journals.ekb.eg/article_1772.html
https://ejabf.journals.ekb.eg/article_1772_57b2ffa0874789284b81d7007574ca62.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
AN EXPERIMENTAL TRIAL FOR INFECTING THE SCAVENGER CATFISH CLARIAS LAZERA WITH TRICHINELLA SPIRALIS LARVAE WITH SPECIAL REFERENCE TO CERTAIN FISH BIOCHEMICAL REACTIONS.
173
195
EN
Adel
Nabih1
Vet. Res. Lab., Giza Province, Animal Health Res. Inst. Egypt.
Mohamed
Rashed
Biochem., Food Deficiency Diseases and Toxicolo. Dept, Animal Health Res. Inst., Dokki. Egypt.
Esam
Rizkalla
Biochem., Food Deficiency Diseases and Toxicolo. Dept, Animal Health Res. Inst., Dokki. Egypt.
10.21608/ejabf.2003.1773
Scavenger catfish Glorias gariepius were experimentally infected with viable infective Trichinella spiralis larvae (1000 larvae/fish), Examination of the intestinal contents revealed the presence of viable larvae (that infect albino rats, xenodiagnosis) up to 48 hours post infection. Adult worms were not detected in the intestines of any of the experimentally infected fish.Trichinella spiralis larvae were not detected neither in the muscles of the infected catfish nor in the diaphragms of albino rats fed on muscles obtained from the experimentally infected fish by the 40th day post infection. Thus, C. gariepius might be considered as a paratenic host for T. spiralis infection and could play a role in the epidemiology of trichinosis.Sequential serum samples from each fish were collected 7 and 40 days post infection. Small but statistically significant changes, in alanine aminotransferase and aspartate aminotransferase occurred after infection. Serum concentration of total protein remained constant, indicating little disturbance of liver function. Infection significantly lowered the relative mobility of serum protein fractions separated by polyacrylamide gel electrophoresis on the 40th day post infection. The relative intensities of the more mobile fraction (# 1) significantly rose, while fractions # 3, 5 and 11 decreased 40 days post infection.It is concluded that the immune response of C gariepius is probably held responsible for the failure
Claries lazera,Trichinella spiralis,serum transaminases,Serum protein,protein fractionation
https://ejabf.journals.ekb.eg/article_1773.html
https://ejabf.journals.ekb.eg/article_1773_caec1daa3a7a01b08af743594dbbaf93.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
FOOD AND FEEDING HABITS OF BAY AD FISH BAGRUS BAJAD (FORSSKAL, 1775) IN El-NOZHA HYDRODROME, ALEXANDRIA, EGYPT
197
211
EN
Shnoudy
Bakhoum
National Institute of Oceanography and Fisheries, Alexandria. Egypt
Samir
Faltas
National Institute of Oceanography and Fisheries, Alexandria. Egypt
10.21608/ejabf.2003.1774
In order to elucidate the food and feeding habits of Bagrus bajed fish, stomach contents of 188 specimens with total body length ranging from 22 to 71cm were examined. Samples were collected monthly during the period from July 2000 to December 2001 from the commercial catch of El-Nozha Hydrodrome. The results of relative gut index indicated that B. bajed is carnivore. The range of its food material is wide, including cichiid species (Oreochromis niloticus, Oreochromis aureus, Sarotherodon galilaeus and Tilapia zillii), mullets ( Mugil cephalus and Liza ramada ), Clarias garlepinus, fish eggs, amphipods (Corophium volutator), shrimps ( Leander serratus) , aquatic insects (chironomid larvae and Coleoptera), vegetable matter and detritus. The maximum feeding intensity was in spring, while the lowest was in winter. Seasonal variation in the diet composition of B bajed revealed that fish prey was the main food item eaten throughout the year except in spring, where it represents the second important food item- after crustaceans. Variation in food species with fish length revealed an increase in the percentage of fish prey in the diet of this species. The diversity in diet of B. bajed, revealed low values in spring increasing in autumn and winter to reach the maximum in summer. Selectivity coefficient for fish prey group of B. bajed showed that cichiid species were negatively selected (-0.08), while the positively selected fishes were Clarias gariepinus (+0^57) and mullets (+ 0.29).
Bagrus bajed,food,Feeding habits,El-Nozha Hydrodrome
https://ejabf.journals.ekb.eg/article_1774.html
https://ejabf.journals.ekb.eg/article_1774_6ec9e4281f6a5250931988ff6a7107dd.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
RESPONSE OF NILE TILAPIA TO DIETARY ANIMAL PROTEIN LEVEL AND POULTRY MANURE FERTILIZER LEVEL m EARTHEN FONBS.
213
227
EN
Esam
Ayaad
Nat. hist of Ocean. Fish, 101 &asr El-Eini Sc.s Cairo, ARE
Mohanmi
Hassowaa
Anirn. Prod. Dspt., Fac. Agric., Cairo Univ. Fayoum Branch. Fayoum. ARE.
10.21608/ejabf.2003.1775
NTile tilapia, Qrvochromis nitonc-ix juveniles averaging about 6.02 Ig in weight, r^re assigned in. eaithen ponds, one teddan(fdn) each. Fish weir: stocked at a rate of 5500/fdn. The v/ork was conducted at cc ■ iimercial fish ih :a at Fayoum Governorate for 22 wk started at Marc in, 15. Treatments were arranged factorally to contain two animal protein levels (24 and 35%) in the diet and two fertilizer levels in ponds (30 and 60 kg N from poultry manure / fdn.), forming four treatments. Diets were isomtrogenous and isocaloric. Data on diets chemical composition, fish growth performance feed utilization and fish body composition as well as a simple economic evaluation were illustrated.<br />The main effects for animal protein level (AP) and poultry manure (PM) levels showed insignificant differences in growth performance, feed utilization and body chemical composition. The simple effects showed significant differences. Generally, growth performance, feed utilization and body composition were positively affected by increasing AP and PM in the diet, even though the diet continued was the lower animal protein (24%), and the higher fertilization rate (60 kg N/ fdn) showed better revenue and revenue/ total production costs (%).
Nile tilapia:, dietary animal protein, feeding rate, poultry manurs,, growth p^iforusaricc, feed utilization, body cozrrposuioru economic evaluation
https://ejabf.journals.ekb.eg/article_1775.html
https://ejabf.journals.ekb.eg/article_1775_feb9d2a06247eb27f352ba0e6d6c5eb2.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
ONTOGENETTC CHANGES IN SOME STRUCTURES OF EARLY EMBRYOS AND LARVAE OF THE BIG HEAD CARP, ARISTICHTHYS NOBILIS
229
257
EN
Nabil
EL-Fiky
Department of Zoology, Faculty of Science, Tanta Univ. Egypt
10.21608/ejabf.2003.1777
The present study contributes to many major topics in the developmental biology of fishes: the development of the early respiratory organs, the differentiation of red muscle layer and its specific function, the deveiopment of the visual system, the time of the first feeding, the development of mechanosensory organs (free neuromasts) and finally the development of scales,A provocative question on these topics could be asked: how growing structures adapt themselves to the constantly changing demands of function and behaviour? Morphological, histological and scanning electron microscopic investigations were combined to study the ontogenetic changes in some selected structures of the developing embryos and larvae of the big head carp, Aristichthys nobilis,It was found that the newly hatched larvae have four gill arches. After three days of hatching, small protuberances (filaments) were found on these arches during which such gills were not yet functional. Larvae of 4-5 days old possess four gill arches with series of relatively short filaments, each possesses numerous secondary lamellae (the true respiratory surface) on both sides.The muscle regions in the pre-hatched embryo consist of scattered undifferentiated myoblasts. The body of the recently hatched larva was surrounded by a single layer of muscle fibers (the gills were still in a rudimentary state). The larvae respire almost exclusively through the superficial layer of red muscle fibers. This layer is to great extent short after hatching but diminishes gradually by contracting towards the lateral region of the body until it merges with (or gives rise to ) the proper red muscle fibers of the adult. The present study suggests that there is a close relationship between the rate of differentiation of gill structures and the rate at which the larval red muscle layer disappears. It seems quite clear the that red layer of muscle fibers and the secondary lamellae of gills serve as organs of gas exchange at different stagesof development. This is expected if one organ is to replace the other without causing a break in respiratory function.In newly-hatched larvae, free neurornasts were already recognized in both the head and trunk regions. During growth, the number of free neurornasts increased. In the head, free neurornasts were located around the eye and nose, their direction of maximum sertsitivity.* Distinct changes in free-neuromasts occurred during the formation of the canal organ. The free neurornasts were become functional as a mechanoreceptors when they well developed cupulae and can detect the origin of mechanical stimuli at this very early stage.The visual system is poorly developed and free of pigment at hatching, and eyes were probably non-functional at this time. The development of eye pigmentation should provide a first feeding larvae with sight.As the larvae develop, the number of the surface neurornasts gradually decreased and finally disappeared. At the same time, the canal organ was formed and the scales has advanced. The lateral-line scales extend posteriorly nearly the tail and anteriorly nearly to the pectoral girdle. Our data show clearly that the disappearance of the free neurornasts was correlated with the appearance of both retinal pigments and body scales.It seems quite clear that right the sequence of the development of the structures necessary for vital functions appears to be'well adapted to the demands.
Development,gills,muscle,Eye,feeding,free neuromasts,Scales,big head carp,Aristichthys nobilfs
https://ejabf.journals.ekb.eg/article_1777.html
https://ejabf.journals.ekb.eg/article_1777_6b85a29987791fd308e18a2406e2db36.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
SOME BIOLOGICAL ASPECTS OF GENUS CHRYSICHTHYS IN THE EGYPTIAN INLAND WATERS
259
277
EN
Shnoudy
Bakhoum
National Institute of Oceanography and Fisheries, Alexandria, Egypt
Mohamed
Ahmed
National Institute of Oceanography and Fisheries, Alexandria, Egypt
10.21608/ejabf.2003.1778
Meristic and morphometric analyses were used to compare Chrysichthys auratus auratus, Chrysichthys auratus longifilis and Chrysichthys rueppelli from commercial catch of River Nile (Al Minya) and El-Nozha Hydrodrome (Alexandria), A total of twenty-nine separate body measurements and counts were taken from each fish. Significant differences were found between Chrysichthys auratus auratus and Chrysichthys auratus longifilis in 4 out of 29 examined characters. These characters were: maximum dorsal rays height, standard length, prepelvic length and dorsal base length. Specific variations revealed that C. auratus differed from C rueppelli significantly in eighteen out of twenty-nine examined characters. The univariate and multivariate analyses . indicated that C. rueppelli was defined from G auratus as the first has larger standard length, relatively short first dorsal fin ray; larger head width; longer upper and lower jaws lengths and caudal peduncle, pectoral fin and prepelvic lengths are longer than that of C. auratus. Discriminate function analysis showed that the percent correct site allocation were 96% for C. auratus auratus, 61% for C auratus longifilis and 92% for. C. rueppelli. All analyses suggested that Chrysichthys auratus and Chrysichthys rueppelli are distinct species. The relative abundance of these species revealed that C. auratus auratus dominated the catch by number in both regions. Length-weight relationship and condition factor indicated that C auratus auratus and C. auratus longifilis inhabiting El-Nozha Hydrodrome are heavier than those from. River Nile. In addition, the natural mortality coefficient for examined species inhabiting in El-Nozha Hydrodrome was comparatively lower than those from River Nile.
Chrysichthys auratus auratus,C. auratus longifilis,C. rueppelli,Biometric,Length-weight relationship,coefficient of condition,Natural mortality
https://ejabf.journals.ekb.eg/article_1778.html
https://ejabf.journals.ekb.eg/article_1778_84cf7676e0a2c9b1ea7d3b555aff3a92.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
STUDIES ON HYSYTEROTHYLACIUM SP. (NEMATODA: ANISAKIDAE) INFECTING KUWAITI FISHES.
279
308
EN
Bahija
Al-Behbehani
Science Department, College of Basic Education, Public Authority for applied Education and Training, Kuwait,
10.21608/ejabf.2003.1779
Agroup of 186 fish specimens were obtained from Kuwait water including 37 silver pomfrets, (Pampas argenteus), 71 greasy groupers, (Epinephelus tauvina) and 78 Malabar blood snapper (Lutjanus malabaricus). They were examined during the period from December, 2001 to November, 2002 for helminth infection. Only one snapper fish and a small proportion of the silver pomfrets were found infected with the nematode, Hysterothylacium sp., but all the greasy groupers were free of infection with any species of helminthes. Thus no- cestodes, trematodes, monogeneans or acanthocephalans were found yet in any of the examined fishes. The relationships between level of infection, sex of the infected fishes, and the environmental factors are hereby discussed.
Hysterothylacium,Nematoda,Anisakidae,Fishes,Kuwait
https://ejabf.journals.ekb.eg/article_1779.html
https://ejabf.journals.ekb.eg/article_1779_2e7dbbdc1736fa2f9682b1c2080cd3a0.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
EFFECT OF PROTEIN LEVELS ON GROWTH PERFORMANCE AND ECONOMICAL EVALUATION OF NILE TILAPIA (Oreochromis niloiicus)
309
318
EN
Abd El-Hamid
Eidl
Department of Animal & Fish Production, Fac.'Of Agric. Suez Canal Univ. - Ismailia - Egypt.
Mostafa
Saiid
Department of Aquaculture, Desert Research Center, Egypt
Rahman
Salama
Department offish Economics, Central Laboratory for Aquaculture at Abbassa, Sharkia Governorate, Egypt.
10.21608/ejabf.2003.1780
Six approximately isoenergetic diets were formulated with protein levels from 20% to 45% in increments of 5%. The effects of varying dietary protein level on growth performance and economic efficiency were studied. The best growth rate was obtained with 30% dietary protein, followed by the diets containing 35,40, 45,25 and 20% protein, respectively. Feed conversion ratio was improved with increasing dietary protein levels up to 30%. Protein efficiency ratio was decreased with increasing dietary protein levels.Body protein was increased with increasing dietary protein levels up to 45%. There was an inverse relationship between the body moisture and lipid contents. Dietary protein levels did not affect the body ash content. From the economical point of view, the highest net return percentage of the total costs was 110.3% as recorded by the 3.0% Protein; followed by 102.4 % (25%. Protein) 99.4% (20%. Protein); 94.1 % (35%. Protein); 59.0 % (40%. Protein) and finally 48.6 % for (45%. Protein). The optimum dietary protein level for Nile tilapia (weighing 20g) was 30% and the feeding rate was 3% of body weight.
protein levels,Nile tilapia,Growth performance,productivity,economic efficiency
https://ejabf.journals.ekb.eg/article_1780.html
https://ejabf.journals.ekb.eg/article_1780_e65f0f5698f22479d23113b30b70b091.pdf
The Egyptian Society for the Development of Fisheries and Human Health (ESDFHH)
Egyptian Journal of Aquatic Biology and Fisheries
1110-6131
2536-9814
7
3
2003
06
01
الأضرا الناتجه في أنسجه کليه سمکه الطوبار البوريه کدلاله للتلوث البيئي في بحيره المنزله ,مصر
1
15
EN
10.21608/ejabf.2003.1781
https://ejabf.journals.ekb.eg/article_1781.html
https://ejabf.journals.ekb.eg/article_1781_db8eaf0c9823badfafec826dddca1fa7.pdf