The effects of fish meal replacement by yeast based nucleotides on growth body composition and digestive enzyme activity in rainbow trout juveniles Oncorhynchus mykiss
HUNT, ARZU ÖZLÜER | YILMAZ, FERBAL ÖZKAN | ENGİN, KENAN | YALIN, SERAP | ŞAHİN, NEFİSE ÖZLEN
This 60 day study investigated the effects of organically certified nucleotide yeast-derived protein source (Nu-Pro®) on growth, feed efficiency, fillet proximate composition and digestive enzymes in rainbow trout (Onchorhyncus mykiss). Diets were isonitrogenous and isocaloric. Three experimental diets wherein 20%, 40% and 60% of the fish meal content was replaced by Nu-Pro®, were compared to the control diet in which the crude protein content was anchovy fish meal and corn gluten meal. The rainbow trout (initial weight 27 g/fish) were fed twice daily in 200-l Aqaria. Live weight gain increase ranged from 125-195% in fish fed the experimental diets. Results indicated that up to 40% fish meal protein can be replaced by Nu-Pro® without compromising growth rates, feed efficiency or the fillet...
Effect of Mannan Oligosaccharide on Growth Body Composition and Antioxidant Enzyme Activity of Tilapia Oreochromis niloticus
HUNT, ARZU ÖZLÜER | YILMAZ, FERBAL ÖZKAN | YALIN, SERAP
The effects of three inclusion levels of mannan oligosaccharides (MOS) derived from the outer cell wall of a select strain of Saccharomyces cerevisiae (Bio-Mos, Alltech Inc, USA) on growth, feed utilization, body composition, and antioxidant enzyme activity of tilapia (Oreochromis niloticus) were determined. Specimens (12 g) were fed a commercial diet supplemented with 0‰, 2.5‰, 3.5‰, or 4.5‰ dietary MOS for 60 days. Food conversion rates (FCR), specific growth rates (SGR), and the biochemical composition of muscle tissue were determined. Growth was greatest, protein was highest, and lipid was lowest in fish fed the 2.5‰ MOS diet. The FCR was significantly better in all MOS-treated groups than in the unsupplemented control. At the end of the study, antioxidant enzyme activity of superoxid...
Evaluation of Fluorescence in situ Hybridization (FISH) and Polymerase Chain Reaction (PCR) for Identification of Enterococcus spp. in Fish and Water
ÖZER, Selmin | BÖREKÇİ, Gülay | KANIK, Arzu
Three methods for identifying Enterococcus spp. and E. faecalis were compared. Using conventional culture methods, 99 isolates from rainbow trout (Oncorhynchus mykiss Walbaum) and water samples were identified as Enterococcus spp. and 86.7% of these were identified as E. faecalis. Using the oligonucleotide probes Eub338, NonEub, Enc145, Efs129, and Str, fluorescence in situ hybridization (FISH) identified 73.7% of the 99 Enterococcus spp. as Enterococcus spp. and 58.6% as E. faecalis. Using polymerase chain reaction (PCR) methods, 88.9% of the 99 samples were identified as Enterococcus spp., 36.4% as E. faecalis, and none as E. faecium. Thus, the consistency between conventional, FISH, and PCR methods was inadequate.
Effects of Organic Selenium on Growth, Muscle Composition, and Antioxidant System in Rainbow Trout
HUNT, ARZU ÖZLÜER | YILMAZ, FERBAL ÖZKAN | YALIN, SERAP
This experiment was conducted to understand the effects of organic selenium on rainbow trout, Oncorhynchus mykiss. Fish (33.47±0.15 g; n = 216) were randomly assigned to four treatment groups consisting of three replicates of 18 fish each in 100 x 100 x 125 cm cages. The fish were fed a basal diet supplemented with 2, 3, or 4 mg/kg organic Se (Sel-Plex®) supplementation for 8 weeks. Muscle of fish fed the unsupplemented control diet had a lower (p