Evaluation of digestibility and microbial protein production of diets containing different forms of flaxseed with two levels of rumen undegradable protein in vitro condition in ruminants
Investigation of fermentation parameters by gas production method is one of the common methods for evaluating feeds and can be a reflection of the fermentation pattern in the rumen. The gas production method in a relatively short time can evaluate the fermentation process of feeds and a large number of samples, and also used to determine the quantity and quality of value and digestion rate of a feed. In recent years, the flaxseed and its oil, due to high concentration of α-linolenic acid extremely considered and used as a fat supplementation in diets of ruminant, but one of the most important concerns in the nutrition of oilseeds is the negative effects of their unsaturated fatty acids on ruminal fermentation. The aim of this study was to evaluate the digestibility, gas and microbial protein production of diets with different forms of flaxseed (whole, grounded and extruded) and the high (40%) and low (20%) levels of rumen undegradable protein (RUP).
Two hundred mg of each feed sample was incubated with ruminal fluid with buffer and gas production was measured at 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, 96 and 120 h. The experimental diets were: 1) diet no flaxseed + 20% RUP; 2) diet no flaxseed + 40% RUP; 3) diet containing 10% whole flaxseed + 20% RUP; 4)diet containing 10% whole flaxseed + 40% RUP; 5) diet containing10% grounded flaxseed + 20% RUP; 6) diet containing10% grounded flaxseed + 40% RUP; 7) diet containing10% extruded flaxseed + 20% RUP, and 8)diet containing 10% extruded flaxseed + 40% RUP.
The results showed that the amount of gas production during 96 hours incubation was higher with control diets compared to other diets (255.8 vs 217.8, 198.1 and 200.4 ml/g DM, P=0.001) and also at 20% RUP level (255.5 vs 210.1 ml/g DM, P=0.049). True digestibility of control diets (684 vs 568, 619 and 538 mg/g DM) and NH3-Nof diets containing grounded flaxseed compared to other diets (1.12 vs 0.41, 0.49 and 0.21 mg), was higher (P>0.05), but microbial nitrogen production by diets containing grounded flaxseed compared to other diets (2.72 vs 3.29, 3.36 and 3.45 mg), was lower (P>0.01). The disappeared DM (161.6 vs 149.9 mg), neutral detergent insoluble nitrogen (1.63 vs 1.35 mg) and NH3-N (0.76 vs 0.35 mg) with 40% RUP, and microbial nitrogen production (3.48 vs 2.93 mg) in 20%RUP (P>0.05), was higher.
Since one of the main objectives of the present experiment was to examine the production of microbial protein in experimental diets, diets containing whole and extruded flaxseed despite their low digestibility, but showed higher microbial protein production. On the other hand, 20% RUP level also showed the highest amount of gas and microbial protein production. So, it seems from an economic point of view as well as the performance of the diets, using a diet containing 10% extruded flaxseed along with 20% RUP can be beneficial and effective.
- حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران میشود.
- پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانههای چاپی و دیجیتال را به کاربر نمیدهد.