Kürşat Fırat

Allometric Growth in Hatchery-Reared Gilthead Seabream

Abstract Morphological development and allometric growth were investigated in the gilthead seabream Sparus aurata during larval development until the end of the weaning period on day 41. Fertilized eggs had a diameter of 1.01 ± 0.02 mm (mean ± SE) and a lipid vesicle diameter of 0.227 ± 0.021 mm. Mean total length (TL) was 2.68 ± 0.04 mm for newly hatched larvae and 3.57 ± 0.09 mm at the onset of feeding (4 d after hatching [DAH]). At 10 DAH, initial swim bladder inflation occurred, mean TL was 4.19 ± 0.08 mm, and notochord length (NL) was 4.00 ± 0.07 mm. At 16 DAH, the swim bladder became more elongated, TL was 5.13 ± 0.09 mm, and NL was 4.94 ± 0.07 mm. Notochord flexion occurred at 6.46 ± 0.11 mm TL on 23 DAH, and the complement of the flexion occurred at 8.67 ± 0.109 mm TL on 35 DAH. At the end of the weaning period (at 41 DAH), larvae were 10.85 ± 0.116 mm TL. The majority of all allometric changes from the inflection point were expressed during the larval stage and integrated with the metamorphosis s...

Ozone Disinfection of Eggs from Gilthead Seabream Sparus aurata, Sea Bass Dicentrarchus labrax, Red Porgy, and Common Dentex Dentex dentex

The risk of fish pathogen transmission via eggs can be reduced by disinfection in ozonated seawater. The aim of this study was to determine the suitable conditions for ozone disinfection of the eggs of gilthead seabream Sparus aurata, sea bass Dicentrarchus labrax, red porgy Pagrus pagrus, and common dentex Dentex dentex. The eggs were disinfected with a concentration (C) of 0.5 mg of ozone/L of water at four different exposure times (T = 2, 4, 8, and 16 min). The hatching rate was determined in triplicate for each treatment. Bacterial colonies were counted on tryptic soy agar and thiosulfate-citrate-bile salts-sucrose agar. At the end of the experiment, bacterial load and hatching rate were assessed together to determine the optimal ozone treatment values, which were estimated in CT units (i.e., C [= 0.5 mg/L] x T [min]). Optimal values were CT 2-4 (T = 4-8 min; 18 degrees C) for gilthead seabream and red porgy, CT 2 (T = 4 min; 18 degrees C) for common dentex, and CT 4 (T = 8 min; 15 degrees C) for sea bass.

SERUM BIOCHEMISTRY OF FARMED BLUEFIN (Thunnus thynnus L.) IN THE AEGEAN SEA

Values of blood biochemistry are important for all animals in terms of health and welfare, providing knowledge of evidence in diseases. One of the most economically important fish species bluefin tuna-BFT ( Thunnus thynnus L.) in aquaculture considering high prices in the related business. Accordingly, farmers care about fattening fishes and some analyses provide significant knowledge, especially blood analyses for them. In the study, blood samples were recovered from fishes (10 male and 12 female) in fattening farms at Ildir, Cesme, Izmir province, East of Aegean Sea. Fork length and weight values were 140–180cm, and 40–80kg, respectively. Water quality parameters such as temperature, salinity, dissolved oxygen, pH and turbidity were indicated as 16–20 o C, ‰ 35.7–38.2g L -1 , % 6.9-7.8mgL -1 , 36.8–38.2m. The research measured uric acid 4.32mg/100mL -1 , creatinine 1.12mg/100mL -1 , serum urea concentration 15.04mg/100mL -1 ), albumin 2.30g/100mL -1 , globulin 2.56g/100mL -1 , total protein 6.15g/100mL -1 , serum glutamic oxaloacetic transaminase 178.24UL -1 , serum glutamate pyruvate transaminase 141.52UL -1 , alkaline phosphatase 54.26UL -1 , g-glutamyl transferase 220.14UL -1 , total cholesterol 272.04mg/100mL -1 , triglycerides 320.75mg/100mL -1 , high-density lipoprotein 88.68mg/100mL -1 and low-density lipoprotein 180.18mg/100mL -1 . Results during the fattened period in growing cages indicates that BFTs were under pressure and stress attacks because of unnatural habitats such as feeding, narrow area etc. in farm area. Also, males were more sensitive and undergo more stress than females.