IJA Volume 57, Issue 1, 2005
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ItemPotential Of Poultry By-Product Meal As A Substitute For Fishmeal In Diets For Black Sea Turbot Scophthlmus Maeoticus: Growth And Nutrient Utilization In Winter(Israeli Journal of Aquaculture - BAMIGDEH, 2005)The use of poultry by-product meal as an alternate dietary protein for Black Sea turbot Scophthalmus maeoticus (initial avg wt 18 g) in winter was evaluated. Triplicate groups of 15 fish were fed one of five isoenergetic (gross energy 20.5±0.21 kJ/g) and isonitrogenous (protein con- tent 55±0.35%) diets with 25%, 50%, 75%, or 100% of the fishmeal protein replaced by poultry by-product protein. White fishmeal was the sole protein source in the control diet. There was no significant (p<0.05) reduction in growth performance of the turbot fed the 25% replacement diet compared to the control diet (100% fishmeal). At the replacement levels of 50%, 75%, and 100%, however, there was a severe decrease in feed intake, growth performance, feed utiliza- tion, protein efficiency ratio, and apparent net protein utilization. Results indicate that up to 25% of the fishmeal protein can be replaced by poultry by-product meal with no negative effects in fish performance at temperatures ranging 6-8°C.
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ItemEffects Of Androstenedione, A Phytoandrogen, On Growth And Body Composition In The African Catfish Clarias Gariepinus(Israeli Journal of Aquaculture - BAMIGDEH, 2005)The present study investigated the effects of a phytoandrogen, androstenedione, on growth, body composition, and survival in African catfish, Clarias gariepinus. Three concentrations (25, 50, and 75 mg/kg feed) were administered for 120 days. Survival of treated groups did not sig- nificantly differ from the control and ranged 94.44-97.78%. A significantly higher weight gain was obtained in the 50 and 75 mg/kg diets. The fish fed these diets also had significantly better food conversion and protein efficiency ratios. Apparent net protein utilization was better in treated groups than in the control. The protein and lipid contents of the carcass of treated fish were sig- nificantly higher than in the control, with the highest contents in the 50 mg/kg treatment. The highest ash content was in the 25 mg/kg treatment. In overall parameters, 50 mg androstene- dione per kg diet was the optimal concentration.
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ItemEffect Of Stimulants On Feeding Response, Feeding Behavior, And Growth Of Fry Of Sea Bass, Lates Calcarifer (Bloch, 1790)(Israeli Journal of Aquaculture - BAMIGDEH, 2005)The influence of four stimulants (glycine, proline, L-lysine, and Bombay duck fishmeal) on the feeding behavior of sea bass fry was studied. The substances were added at a level of 1% of the weight of moist pellets made from purified diets. Feeding responses were observed in glass tanks containing one or two fish.The fishmeal had significantly greater stimulating effect on the feeding behavior than the chemical substances. Feeding responses were significantly different when there were two fish in the tank. Inclusion of fishmeal at a 10% level (compared to 1%, 5%, 7.5%) produced the greatest ingestion response (50%). Compared to 7.5%, inclusion at 10% produced a significantly higher weight gain (0.54±0.03 g), FCR (1.79), and PER (1.20). The pre- sent investigation revealed that Bombay duck meal is a better natural fish feed stimulant than the tested chemicals.
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ItemUse Of Glucan From Saccharomyces Cerevisiae As An Immunostimulant In Carp: Impact On Hematology, Phagocyte Function, And Infection With Aeromonas Hydrophila(Israeli Journal of Aquaculture - BAMIGDEH, 2005)Glucan was extracted from yeast (Saccharomyces cerevisiae) and subjected to chemical analy- ses. Thin layer chromatography (TLC) revealed that glucan is primarily composed of glucose units and contains 97.2% glucose. Infrared spectrum showed a major band at 883/cm, suggest- ing that glucan is linked to β-glycosidic. Intraperitoneal administration of different doses of glu- can enhanced the survival rate of carp (Cyprinus carpio) infected by Aeromonas hydrophila. When a concentration above 500 μg glucan per fish was administered, survival relative to the uninfected control was 100%. The total leukocyte count and neutrophil and monocyte popula- tions increased after administration of the glucan. The maximum effect occurred on day 6 after injection. Macrophages of compound-administrated test animals significantly increased produc- tion of superoxide anions, efficiently killing the bacterial pathogen. This study showed that glu- can can be effective in inducing non-specific cellular defense mechanism in carp.
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ItemEffect Of Bacterial Load In Feeds On Intestinal Microflora Of Seabream (Sparus Surata) Larvae And Juveniles(Israeli Journal of Aquaculture - BAMIGDEH, 2005)Aerobic bacterial flora in the intestines of seabream (Sparus aurata) larvae and juveniles, in diets they were fed (rotifers, brine shrimp, artificial diet), and in their rearing water were analyzed. Fish fed live feeds had a higher bacterial count than the fish fed the artificial diet. In rotifers, the total bacteria count was 8.7 x 106 and Pseudomonas dominated the flora (60.2%). In larvae fed rotifers, the bacteria count was 9.8 x 102, with Pseudomonas (48.4%) and Vibrio (28.3%) domi- nating. In brine shrimp, the bacterial count was 1.7-3.5 x 107 cfu/g and Vibrio (73.7-81.3%) was more prevalent than Pseudomonas (10.2-15.5%). In larvae fed brine shrimp, the bacterial count was 5.3 x 104-1.8 x 105 and Vibrio (61.2-70.1%) dominated. The count for the artificial feed was 1.2 x 104 with Pseudomonas slightly dominating while for juveniles fed artificial feed the count was 2.3 x 104, with Vibrio slightly dominating. Bacterial microflora in the rearing water ranged from 1.3 x 102 to 3.2 x 103 cfu/ml. The study showed that the microflora of fish feeds quantita- tively and qualitatively affect the intestinal microflora of seabream larvae and juveniles.
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ItemEffect Of Photoperiod On Plasma Thyroxine Hormone Level Of Mirror Carp (Cyprinus Carpio) Raised At A Low Water Temperature In A Controlled Environment(Israeli Journal of Aquaculture - BAMIGDEH, 2005)The objective of this study was to examine the effects of various lighting regimes on the plasma thyroxin hormone (T4) level of mirror carp (Cyprinus carpio). The carp were kept at the low tem- perature of 9°C to eliminate any influence of water temperature on feed intake, growth, and the hormone level. Treatments were 8 h light:16 h dark, 12 h light:12 h dark, and 16 h light:8 h dark. Plasma thyroxin levels were measured every four weeks for 12 weeks. The levels were signifi- cantly higher (p<0.05) in the groups exposed to 8 or 12 h light than in the group exposed to 16 h. The T4 levels significantly dropped with time in all photoperiods.
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ItemEffects Of Pre-weaning Feeding Frequency On Growth, Survival, And Deformation Of Senegalese Sole, Solea Senegalensis (Kaup, 1858)(Israeli Journal of Aquaculture - BAMIGDEH, 2005)Despite much interest in the production of Senegalese sole (Solea senegalensis) in southern Europe, weaning of this species onto artificial diets is problematic and varying results are obtained. The aim of this study was to test two feeding frequencies during a 13-day pre-wean- ing period and assess their impact on the growth and survival of Senegalese sole. Postlarvae were fed Artemia metanauplii with a peristaltic pump every hour for 12 hours per day or twice daily (morning and late afternoon). Both groups were suddenly weaned onto a commercial diet for an additional 30 days. At the end of the experiment, the relative growth rate and final dry weight were significantly higher and the survival significantly lower in the 12-hour treatment than in the twice-daily treatment. The feeding frequency had no effect on condition factor. The inci- dence of deformities was about 80% in both treatments.
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ItemGrowth, Behavior, And Mating Of Pharaoh Cuttlefish (Sepia Pharaonis Ehrenberg) In Captivity(Israeli Journal of Aquaculture - BAMIGDEH, 2005)The pharaoh cuttlefish (Sepia pharaonis) was successfully reared from egg to an average size of 168 mm mantle length and 521 g in 210 days, using simple biological filtration systems. The period of egg incubation was 15 days at a temperature of 27-31 ̊C. Hatchlings were reared at a stocking density of one animal per liter during the first month; density was reduced as growth proceeded. Food items consisted of live mysids, Artemia salina, juvenile fishes, and prawns. Juveniles were gradually acquainted with dead food items such as caridian prawns and small fishes. The present study shows that the pharaoh cuttlefish can be reared in captivity with a sur- vival rate of 41%, using live feeds during the first 50 days. Future commercial scale culture of this species depends on development of artificial feeds and high density culture systems.