Behire Işıl Didinen

Effect of protease and phytase supplementation on growth performance and nutrient digestibility of rainbow trout (Oncorhynchus mykiss, Walbaum) fed soybean meal-based diets

ABSTRACT An experiment was conducted to evaluate effects on growth, body composition and nutrient digestibility of addition protease and phytase to soybean meal-based diet in rainbow trout. Seven soybean meal-based diets were prepared by adding protease, phytase and mixture of both enzymes at two different levels (1 and 2 g kg−1) to a base diet without enzymes. Mixed enzymes (1, 2 g kg−1) were prepared by adding protease and phytase at the same doses (0.5 + 0.5 and 1 + 1 g kg−1). Diets consisted of 31% fish meal and 44% dehulled hexane extracted soybean meal. At the start of the experiment, 45 rainbow trout (initial mean body weight 88 g) were stocked into each of 21 fibre tanks. After 90 days, there were no significant differences on the growth, feed conversion ratio, digestibility of protein and lipid among the groups. Results of this study showed that the addition of protease or phytase as mix to soybean meal-based diet could not increase growth and nutrient digestibility in trout.

Immunohistochemical evaluation of experimental Vagococcus salmoninarum infection in rainbow trout (Oncorhynchus mykiss, Walbaum 1792)

The aim of this study was to investigate the pathogenesis and histopathological and immunohistochemical findings in rainbow trout (Oncorhynchus mykiss) following experimental vagococcosis. For this purpose, 60 rainbow trout were used. The experimental study used the pathogen Vagococcus salmoninarum. The fish were intraperitoneally (IP) administered with an inoculate containing 0.1 mL of the bacteria, resulting in a dose of 1.2 × 10(9) cfu mL(-1) per fish. For histopathological observations, tissue samples were taken from fish that died during the experiment and fish that survived until the end of the trial (60th day). All the tissue samples were immunohistochemically stained by the avidin-biotin-peroxidase complex and immunofluorescence methods using polyclonal antibody to detect V. salmoninarum antigens. In immunoperoxidase staining, positive reactions to bacterial antigens were most commonly seen in the kidney, heart and liver. In the immunofluorescence analysis, the distribution of antigens in the tissue and organs was similar to that observed with the immunoperoxidase staining. The results reveal an important correlation between histochemical and immunohistochemical staining in demonstrating the distribution of V. salmoninarum antigens in the affected tissues.

Effect of β-Mannanase and α-Galactosidase Supplementation to Soybean Meal Based Diets on Growth, Feed Efficiency and Nutrient Digestibility of Rainbow Trout, Oncorhynchus mykiss (Walbaum).

A 12-week feeding trial was conducted with 87 g rainbow trout to evaluate the effects on growth performances, feed efficiency and nutrient digestibility of adding β-mannanase and α-galactosidase enzymes, solely or in combination. Seven diets were prepared by adding β-mannanase, α-galactosidase and mixed enzyme at two different levels (1 g/kg and 2 g/kg) to control diet (without enzyme) including soybean meal. Mixed enzymes (1 g/kg, 2 g/kg) were prepared by adding β-mannanase and α-galactosidase at the same doses (0.5+0.5 g/kg and 1+1 g/kg). At the end of the experiment, addition of β-mannanase, α-galactosidase and mixed enzyme to diet containing 44% soybean meal had no significant effects on growth performance and gain:feed (p>0.05). In addition, adding β-mannanase, α-galactosidase and mixed enzyme in different rations to trout diets had no affect on nutrient digestibility and body composition (p>0.05).

Farklı Yem ve Stok Yoğunluğunun Astacus leptodactylus (Esch., 1823) Juvenillerinin Hayatta Kalma ve Büyüme Performansı Üzerine Etkisi

Bu calismada, iki farkli yem (canli yem- Daphnia magna ve ticari alabalik yemi) ve stok yogunlugunun (650 ve 1300 juvenil/m 2 ) Astacus leptodactylus yavrularinin hayatta kalma ve buyume performansi uzerine kombine etkileri arastirilmistir. Denemede II. donem yavrular kullanilmistir. Deneme sonunda, yavrularin hayatta kalma ve buyume parametreleri degerlendirilmistir. Bu calismanin sonuclari, diyetlerin hayatta kalma oranlari uzerinde etkili olmadigini, ancak artan stok yogunlugunun yasama oranlarini azalttigini gostermistir. En iyi yasama orani % 21,99 olarak 650 juvenil/m 2 stok yogunlugunda canli yemle beslenen grupta saglanirken, en dusuk yasama orani ise % 10,84 olarak 1300 juvenil/m 2 stok yogunlugunda alabalik yemi ile beslenen grupta elde edilmistir. Denememe sonunda en yuksek vucut agirligi, 650 juvenil/m 2 stok yogunlugunda alabalik yemi ile beslenen grupta bulunmustur. Calismamiz sonucunda ayrica, yavru kerevit beslenmesinde her iki yem ile beslenen yavrularda hayatta kalma oranlari uzerinde stok yogunlugunun onemli bir etkiye sahip oldugu gorulmustur.

Bazı Bakteriyel Balık Patojenlerine Karşı Bazı Bitkisel Uçucu Yağlarının Antibakteriyel Aktivitesi

B u ara stirmada, karanfil ( Eugenia caryophyllata ), nane ( Menta piperita ) ve lavanta ( Lavandula hybrida ) ucucu yaglarinin kimyasal bilesimleri ve bakteriyel balik patojenler, Aeromonas sobria, Aeromonas salmonicida achromogenes, Aeromonas caviae, Aeromonas hydrophila, Vibrio anguillarum, Vibrio ordalli, Vibrio alginolyticus , Yersinia ruckeri , Flavobacterium psychrophilum, Lactococcus garvieae ve Vagacoccus salmoninarum ’a karsi in vitro a ntibakteriyel etkileri arastirilmistir. Sonuc olarak, karanfil ucucu yaginin guclu antibakteriyel etki gosterdigi tespit edilmistir. Bununla birlikte, nane ve lavanta yaglari orta derecede etkili bulunmustur.

Ichthyobodo spp. Infection in Meagre (Argyrosomus regius) from Turkey: Parasitological and Pathological Findings.

OBJECTIVE The aim of this study is to describe the first report of Ichthyobodo spp. infection in meagre (Argyrosomus regius) fry in a marine aquaculture facility in Turkey. METHODS The material of the study was composed of 30 meagre A. regius in 2-3 g weight taken from the fry adaptation unit of a fish farm in the Aegean Sea. In this study, parasitological and pathological examinations were performed on the meagre. Ichthyobodo spp. was determined on the body surfaces and gills. RESULTS Pathological examination revealed grayish mucous and erosions between the pin head and lentin over the skin of the examined specimens. Microscopic examinations revealed significant spongiosis, vacuolar degeneration, and hyperplasia in epidermal malpighian cells and hyperplasia in goblet cells. CONCLUSION In the present study, Ichthyobodo spp. infection was for the first time determined in an alternative cultured meagre in Turkey.