O. Kahraman

Determination of protein degradability of alfalfa hay via buffer or protease

Abstract This study was conducted to determine the effect of different vegetative periods on protein fractions of alfalfa hay and to compare two different methods for estimation of its protein degradability. In this study, 44 alfalfa hay samples cut in late vegetative, late bud, early bloom and late bloom were used. Crude protein decreased with advancing maturity (p < .05), but neutral detergent insoluble nitrogen and acid detergent insoluble nitrogen were similar. Protein degradability of the samples was estimated using Streptomyces griseus protease or borate–phosphate buffer, kinetic model, as described in Cornell Net Carbohydrate Protein System (CNCPS). Alfalfa hay samples were subjected to proteolysis for 30 h with 0.115 U/mL or 0.230 U/mL of the protease at pH 6.8. There was a moderate correlation (0.66, 0.72) between enzymatic and buffer method estimates with protein degradation. As vegetation progresses, rapidly degradable fraction (A) decreased (p < .05) and undegradable fraction (C) increased (p < .05), while potentially degradable fraction (B) was unchanged. Rumen degradable protein content decreased (p < .05) with advancing maturity. The enzyme/duration limits should be standardised and investigated whether the protease enzyme alone is sufficient for all forages.

Fatty Acid Composition of the Muscle Lipids of Five Fish Species in Işıklı and Karacaören Dam Lake, Turkey

Total fatty acid composition of muscle lipids in some fish species (Cyprinus carpio (Işıklı Dam Lake), Tinca tinca (Işıklı Dam Lake), Scardinius erythrophthalmus (Işıklı Dam Lake), Cyprinus carpio (Karacaören Dam Lake), and Carassius carassius (Karacaören Dam Lake)) was determined by gas chromatography. Polyunsaturated fatty acids (PUFAs) of Cyprinus carpio (Işıklı Dam Lake) were found higher than PUFA of other species. Palmitic acid was the highest saturated fatty acid (SFA) in Tinca tinca (24.64%). Oleic acid was the highest monounsaturated fatty acid (MUFAs) in Cyprinus carpio (Işıklı Dam Lake) (19.25%). The most abundant polyunsaturated fatty acid in Scardinius erythrophthalmus was docosahexaenoic acid (DHA) (17.94%). Total ω3 fatty acid composition was higher than the total ω6 fatty acids of Cyprinus carpio in both dam lakes. ω3/ω6 rates in Cyprinus carpio (Işıklı Dam Lake), Tinca tinca, Scardinius erythrophthalmus, Cyprinus carpio (Karacaören), and Carassius carassius were 2.12, 1.19, 2.15, 2.87, and 2.82, respectively.