IJA Volume 58, Issue 2, 2006

Permanent URI for this collection


Recent Submissions

Now showing 1 - 8 of 8
  • Item
    Growth and body composition of European catfish (Silurus glanis L.) fed diets containing different percentages of protein
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Bekcan, Süleyman ; Dogankaya, Levent ; Cakirogullari, Gul Celik
    European catfish (Silurus glanis) were fed anchovy-based diets containing 30, 35, 40, or 44% crude protein to satiation for 112 days. Data were collected to determine the relationship between dietary protein level and mean weight gain, specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER), daily growth index (DGI), average daily growth (ADG), feed efficiency (FE), and survival. The highest mean weight gain and SGR were obtained with the 40% (59.94 g and 0.74, respectively) and 44% (56.15 g and 0.71) diets. The best FCR (0.97), PER (2.62), DGI (2.18), ADG (1.14), and FE (1.04) were obtained with the 40% protein diet (2.75 kcal/g, digestible energy). Survival was 100% in all treatments. Results indicate that the optimum level of dietary protein for European catfish is 40%.
  • Item
    cDNA cloning and mRNA expression of growth hormone in Belontiidae (Anabantoidei suborder)
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Degani, G. ; Jackson, K. ; Yom-Din, S. ; Goldberg, D.
    Complete cDNA encoding for the growth hormone (GH) of the Belontiidae fish family (Anabantoidei suborder) was cloned by RACE PCR using several sets of degenerate oligonu- cleotides. GH cDNA of the pearl gourami (Trichogaster leeri; pgGH), cloned from the pituitary, included the 5’ and 3’ noncoding sequences of 44 bp and 181 bp, respectively, and consisted of 840 bp that encoded for a prehormone of 204 amino acid (aa) residues. GH cDNA of the blue gourami (T. trichopterus; bgGH) and its deduced aa sequence had the same lengths as those of the pgGH, with nucleotide and aa identities of 97% and 99%, respectively. GH cDNA cloned from the dwarf gourami (Colisa lalia; dgGH) differed from both pgGH and bgGH. The identity of the dgGH cDNA nucleotides was 88%, compared to pgGH and bgGH. However, the identity of the deduced dgGH aa sequence was 97% when compared to bgGH and 96% when compared to pgGH. Nucleotides of GH cDNA of the fighting fish (Betta splendens; ffGH) had an identity of 82% to those of pgGH and bgGH, and 81% to the dwarf gourami. Higher identity was found among the aa sequences than among the nucleotide sequences. The identity of the cloned aa ffGH compared to bgGH, pgGH, and dgGH was 93%, 92%, and 91%, respectively. Higher levels of GH mRNA were found in females in immature, vitellogenic, and mature stages than in males in various stages of gonadal development. No significant differences in the GH transcription level were found between immature and mature females and males. However, the mRNA level decreased significantly during sexual behavior in males. GH sequence and expression may be used as systematic markers for Belontiidae fish and possibly other fish.
  • Item
    Consumer willingness to pay for organic sea bass in Turkey
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Budak, Fuat ; Budak, Dilek Bostan ; Kacira, Ozlem O. ; Yavus, M. Cihan
    This study analyzes the willingness of Turkish consumers to pay for organically farmed sea bass (Dicentrarchus labrax). A contingent valuation survey was conducted during 2004 in six super- markets in Adana, Turkey. An ordered probit analysis with a sample selection model was used to determine the probability of consumers’ willingness to pay for organically farmed sea bass by considering related explanatory variables. Results indicate that 91.5% of the respondents would be willing to pay a premium for organically farmed sea bass. Econometric results suggest that willingness to pay is mainly related to household income, education, food safety concerns, whether the respondent is the primary food shopper in household, and whether there are chil- dren under the age of 10 in the household.
  • Item
    Preliminary study of settlement of flat oyster spat (Ostreaedulis L.) on oyster and mussel shell collectors
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Lok, Aynur ; Acarli, Sefa
    Oyster recruitment was monitored in Karantina Island near Izmir, Turkey, from May to October 1999. The aim of the study was to determine the recruitment pattern for six months and the most suitable time to collect oyster spat from nature. Oyster and mussel shells were used as sub- strates in spat collectors. Five groups of each type of collector were deployed from May to August. The recruitment levels were highest in the groups deployed on June 16, with 4069 and 1575 oyster spats collected on the oyster and mussel shell collectors, respectively. Spat recruit- ment varied considerably between collector types as well as between the outsides and insides of shells (p<0.05). Spats larger than 10 mm were found on the second or third sampling date in each group for both oyster and mussel shell collectors. Barnacles (Balanus sp.) settled on both collector types in high numbers throughout the study. Data suggest that maximum recruitment in this area is most likely to occur on both collector types between May and mid-June.
  • Item
    Effect of dietary Spirulina level on growth, fertility, coloration and leucocyte count in red swordtail, Xiphophorus helleri
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) James, Raja ; Sampath, Kunchitham ; Thangarathinam, Ramasamy ; Vasudevan, Iyyadurai
    Experiments were performed to investigate the influence of different levels of Spirulina (0, 1, 3, 5 and 8%) on feed consumption, growth, fertility, coloration, and leucocyte count in the orna- mental red swordtail, Xiphophorus helleri. Feed intake, specific growth rate (SGR), and mean body length and weight increased as levels of Spirulina increased. Fish fed 8% Spirulina per- formed better than those fed lower levels. The gonad weight and gonadosomatic index (GSI) increased with the Spirulina level and rearing period. Fish fed 8% Spirulina had four times heav- ier gonads than fish fed 0-3% Spirulina. Female X. helleri fed 8% Spirulina released 89 young, significantly higher (p<0.01) than those fed 5, 3, 1, or 0% Spirulina (79, 64, 49, and 41 young, respectively). The total carotenoid content in the fins, skin, and muscle increased with the Spirulina level and the maximum carotenoid content was obtained in fish fed 8% Spirulina. The maximum coloration was in the fins, followed by the skin and muscle in all treatments. Fish fed 8% Spirulina had more monocytes, neutrophils, and lymphocytes and fewer basophils and thrombocytes while control fish showed the opposite trend. The necessity of incorporating an optimum level of Spirulina (8%) in the diet for maximum growth, reproduction, and coloration in X. helleri is discussed.
  • Item
    Traditional Indian herbal extracts used in vitroagainstgrowthofthepathogenicbacteria–Aeromonashydrophila
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Bhuvaneswari, R. ; Balasundaram, C.
    Crude ethanol extracts of Acalypha indica, Acorus calamus, Coleus aromaticus, Heliotropium indicum, and Indigofera aspalathoides were screened for antibacterial activity in vitro against the growth of the fish pathogenic bacteria, Aeromonas hydrophila. Terramycin, widely used to con- trol A. hydrophila in aquaculture, was used as a positive control. The herbs A. calamus and I. aspalathoides warded off the growth of the pathogen completely at minimum inhibitory concen- trations of 1.29 and 2.16 mg/l, respectively. A minimum bacterial concentration of 1.00 cfu occurred at concentrations of 0.77 mg/ml for A. calamus and 1.29 mg/ml for I. aspalathoides. The order of potency of the herbs in warding off growth of A. hydrophila in vitro was ranked: A. calamus, I. aspalathoides, C. aromaticus, A. indica, and H. indicum. The inhibitory potency of A. calamus and I. aspalathoides was significantly higher (p<0.05) than that of the positive control, indicating the potential of these herbs to replace antibiotics in controlling A. hydrophila infection.
  • Item
    Prevalence and pathology of ectoparasites of Mediterranean sea bream and sea bass reared under different environmental and aquaculture conditions
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Vagianou, S. ; Athanassopoulou, F. ; Ragias, V. ; Di Cave, D. ; Leontides, L. ; Golomazou, E.
    Sea bream, Sparus aurata L., and sea bass, Dicentrarchus labrax L., were sampled from an off- shore cage farm in eastern Greece, an inshore cage fish farm in southern Greece, and a lagoon in northern Greece. The prevalence and intensity of Metazoan parasites and factors associated with the prevalence were investigated. In Farm 1 (eastern Greece), ectoparasite prevalence in sea bream and sea bass was 61.5% and 76.9% for Monogenea, none for Isopoda, and 0 and 23% for Copepoda. In Farm 2 the prevalence was 13.3% and 26.3% for Monogenea, 13.7% and 20% for Isopoda, and 0 and 13.6% for Copepoda. In the lagoon, the prevalence of ectoparasites was 100% and 21.9% for Monogenea and Copepoda, respectively. The lagoon had the highest prevalence of parasites among the studied ecosystems, however, the variety did not significant- ly affect the health of the infected fish. In Sparidae, gill lesions were due to monogeneans while skin and eye lesions were due to larvae of the isopod Ceratothoa oestroides that caused severe pathology. Furnestinia echeneis and Diplectanum aequans were host specific to sea bream and sea bass, respectively, and persisted in all aquaculture systems. Lernanthropus kroyeri was host specific and detected only in sea bass from the cage farms.
  • Item
    Digestible energy in dietary sorghum, wheat bran, and rye in the common carp (Cyprinus carpio L.)
    (Israeli Journal of Aquaculture - BAMIGDEH, 2006) Degani, Gad
    The digestibility of protein, fats, carbohydrates, and energy in three feed ingredients (sorghum, wheat bran, and rye) in common carp, Cyprinus carpio, was studied using the chromic oxide method. Three experimental diets were tested. Each contained 52.5% of a basal diet and 47.5% of the test ingredient. The carbohydrate levels in the test ingredients ranged 65-83% and the pro- tein levels ranged 11-18%. Therefore, carbohydrates were the main energy source. Results showed that the digestibility of protein in rye (91.89%) was significantly higher (p<0.05) than in sorghum (71.86%) and wheat bran (80.64%), producing 12.4, 6.7, and 9.3 kJ/g digestible ener- gy, respectively. The lipid levels in the test ingredients were very low, 1-4%. Lipid digestibility was 79.84%, 76.71%, and 82.01% in rye meal, sorghum meal, and wheat bran, respectively.