عنوان پایان‌نامه
تاثیر یونجه خشک بر کیفیت تخمیر و تجزیه پذیری ذرت سیلو شده
- رشته تحصیلی
- مهندسی کشاورزی - علوم دامی - تغذیه دام
- مقطع تحصیلی
- کارشناسی ارشد
- محل دفاع
- کتابخانه پردیس ابوریحان شماره ثبت: 567;کتابخانه مرکزی -تالار اطلاع رسانی شماره ثبت: 51963
- تاریخ دفاع
- ۲۵ مهر ۱۳۹۰
- دانشجو
- سمیه معینی زاده
- استاد راهنما
- علی اکبر خادم, علی اسدی الموتی
- چکیده
- چکیده این تحقیق به منظور بررسی اثر یونجه خشک بر کیفیت تخمیر و تجزیه پذیری ذرت سیلو شده انجام شد. سه علوفه کامل ذرت حاوی ماده خشک 41/18 درصد (S1)، 9/21 درصد (S2) و 63/24 درصد(S3) برداشت شد. به هر کدام از علوفه های ذکر شده 4 سطح یونجه خشک (جاذب) در سطوح صفر، 10، 5 و 20 درصد اضافه شد و هر کدام در 3 تکرار در مینی سیلو، سیلو شد. آزمایش به صورت یک طرح کاملاً تصادفی در قالب آزمایش فاکتوریل 4×3 اجرا شد. سطوح جاذب و رطوبت روی ماده خشک سیلوها اثر معنی دار داشتند. ماده خشک سیلوها با استفاده از 10 و 20 درصد جاذب بیشترین افزایش را نشان داد. چربی خام تحت تأثیر رطوبت، جاذب یا اثر متقابل این دو عامل قرار نگرفت (05/0
- Abstract
- Abstract The main objectives of this study were to evaluate effects of alfalfa-hay (AH) addition to corn forage on the resulting corn silage effluent loss and fermentation. Corn forage harvested at dry matter (DM) contents of 18.41(S1), 21.9 (S2) and 24.63% (S3) and each were ensiled with four levels of AH including 0, 5, 10 and 20% on wet matter basis. Ensiling was performed in mini-silos. The experiment was completely randomized design with a 3×4 factorial arrangement. Level of AH and DM had significant effect on silage DM with greater DM for silages with 10 and 20% AH. Ether extract was not affected by DM, AH or interaction of them (P>0.05), however, AH increased the ash content. In S3 silages concentration of nitrogen increased, while that of neutral- and acid-detergent fibre decreased as the level of AH increased. In S3 silages with 20% AH, the NH3-N as a percentage of total nitrogen was decreased as well. Silage pH increased as the level of AH increased. Aerobic stability of S1 and S2 silages improved as AH was increased, however, S1 and S3 silages had lower pH values at the time silages reached unstable condition. Addition of AH successfully decreased effluent loss and neither of treated silages had effluent at 20% AH addition. Moreover, the S3 silages produced 0 ml effluent at all levels of AH addition. The water soluble carbohydrates of silages increased as the DM content increased, but this was observed only when AH added at 10%. The DM degradability of silages, determined using nylon bag technique with 2 fistulated rams, affected by DM, level of AH and their interaction. In S1 silages the DM degradability increased at 24 and 36 hours of incubation as AH increased, while in S2 silages it did not follow a constant trend. Conversely, in S3 silages DM degradability decreased in all incubation times as the level of AH increased. The NDF degradability increased as the level of AH increased, while decreased as the DM content of original forage increased. Nonetheless, the NDF degradability in S2 silages was greater than that in S1 and S3 silages. The results indicate that adding AH to corn forage with various DM contents resulted in a significant reduction in effluent volume and an increase in aerobic stability of silages and had inconsistent effects on DM and fibre degradabilities. Successful effluent reduction by AH addition warrants further research on nutrient, particularly nitrogen, utilization of these silages when fed to ruminants. When effective effluent reduction would be a goal at ensiling, addition of a minimum of 10% AH to corn forage is recommended. Key words: corn silage, alfalfa hay, absorbent, effluent, degradability
