کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8492841 1552435 2011 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Fecal nitrogen to estimate intake and digestibility in grazing ruminants
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Fecal nitrogen to estimate intake and digestibility in grazing ruminants
چکیده انگلیسی
This study aimed at evaluating forage intake and digestibility in ruminants using fecal nitrogen content, as well as validating a non-linear model to estimate digestibility in ruminants. A total of 58 conventional metabolism trials, carried out with sheep fed 27 forages (offered pure or in mixture) used in Rio Grande do Sul (RS) during the period 1969-1989 was analyzed. OM intake and OM digestibility (OMD) results were regressed linearly against fecal N, and OMD was also estimated from fecal crude protein (N × 6.25) content by a non-linear regression model. Fecal nitrogen excretion estimated forage intake in sheep with an R2 = 0.73, whereas a low R2 value of 0.36 was observed for OMD estimates. The equation obtained using the non-linear model was OMD = 0.7326 − 0.3598 exp [(−0.9052 CP (g/kg OM))/100]. The parameters a (0.7326) and b (0.3598) estimated by the equation for all forages were significant (P<0.00001) and there was no effect of type of forage (P=0.38). The mean prediction error (MSPE), was 0.2379, indicating that the equation fit well to the data. The difference between estimated and observed organic matter digestibility was mainly caused by random variation (0.9765). The results indicated that the equation using the non-linear model developed with all forages can be used with enough precision to estimate the OM digestibility of forage consumed by sheep in Rio Grande do Sul.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Animal Feed Science and Technology - Volume 163, Issues 2–4, 11 February 2011, Pages 170-176
نویسندگان
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