| Total 25 roughage samples in 5 classes and 14 types were collected from such sites of different cities or counties in Heilongjiang province as Harbin, Daqing, 853 farm and Hongwei farm of Baoqing County, and farms in Qinggang County. Nutritional values in 25 roughages samples were totally determined and some new nutritional values were assayed according to the CNCPS. Values of available energy in vitro or in vivo of the roughage were obtained by evaluating profiles of rumen fermentation of the feeds in vitro or in vivo, and regression equations that feed nutrients were used to predict their available energy were established. Finally effectiveness of values both from in vitro and in vivo were compared and analyzed by using animal experiments. The objective of this study was to provide a convenient and effective way for evaluating energy values in roughages. The results were as following:1. Common nutritional values in 25 roughages and some indexes in the CNCPS system were totally determined.2. The profiles of rumen fermentation of the feeds were determined by applying method of in vitro gas production. A preliminary evaluation on nutritional values of roughages in Heilongjiang province was completed according to results of the study, which provided basis for scientific utilization of roughage feed. The results indecated that the leguminosae class in vitro fermentation effect was good, the quality was the most superior; The gramineae fermentation effect was worst, the quality was the poorest; the ensilage class and the straw stalk were medium, the ensilage class forage grass quality surpassed the straw stalk.3. Energy value in vitro and GI index of roughages and diets were determined by using the method of two graded exsomatize digestion and furthermore, applying GI index to evaluate nutritional values of the experimental roughages and diets. The results indicated that there was a consistency in classification of quality of 16 roughages and rations according to the graduation index of GIN, GIA and GIL which calculated from fiber indexes of NDF, ADF and ADL respectivly. Namely: 853 farm alfalfa >Daqing alfalfa>oak alfalfa>Hongwei farm alfalfa>853 farms ensile>Harbin to ensile>the Hongwei farm to ensile>Daqing to ensile>Daqing aneurolepidium chinense>Harbin aneurolepidium chinense> 853 farm Langsdorffii Kunth>Harbin corn straw>Hongwei farm small Langsdorffii Kunth >Daqing corn straw>Hongwei farm corn straw>853 farm corn straw; Oak alfalfa+C>853 farm alfalfa+C> Hongwei farm alfalfa+C>853 farm alfalfa+C>Hongwei farm alfalfa+C>Daqing alfalfa +C>Harbin ensiles the+C>853 farms to ensile+C>Daqing aneurolepidium chinense+C>Hongwei farm to ensile+C >the Harbin aneurolepidium chinense+C>Daqing to ensile+C>Daqing corn straw +C>Harbin corn straw+C>Hongwei farm corn straw+C>Hongwei farm Langsdorffii Kunth+C>853 farm Langsdorffii Kunth+C>853 farm corn straw+C. GIL is more precise to the coarse fodder quality division.4. Prediction model that contents of chemical constituents in feeds were used to forecast their available energy was established according to available energy, laboratory common values and CNCPS indexes in vitro determined in different roughages. The prediction model we built predicts the target data involving nutrition evaluation with high accuracy. 5. Comparisons were made among measured values in vitro, predictive values obtained by establishment of prediction model based on feed classification and predictive values obtained by not establishment of prediction model based on feed classification and the results showed that accuracy of prediction model based on feed classification was higher than the one based not on feed classification.6. Measured values in vivo in different roughages were obtained by metabolism experiment of animals, which were used to test the accuracy of prediction model. The results demonstrated that little differences were detected among measured values in vivo and in vitro or predictive values which came from of classification, and the prediction model can be used in practice with high accuracy and performance.
|
PDF Full Text Request