|Institution:||University of Saskatchewan|
|Keywords:||canola meal; pelleting; protein and carbohydrate; feed value; molecular structures; Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR); model prediction|
|Full text PDF:||http://hdl.handle.net/10388/ETD-2015-02-1952|
Production of and demand for Canadian canola meal have been increased yearly. In order to improve the competitiveness of canola meal domestically and internationally, as well as to develop potential markets for canola meal, it is necessary to develop canola meal-based products that have high feed values and can be easily transported. The objectives of this research were: 1) to investigate the effects of temperature and time of conditioning during pelleting process on the nutritive values of canola meal in terms of chemical profiles, protein and carbohydrate subfractions, and energy values, using the AOAC procedures, CNCPS v6.1 and NRC (2001), respectively; 2) to detect the effects of temperature and time of conditioning during the pelleting process on rumen degradation and intestinal digestion characteristics and predicted protein supply of canola meal, using the in situ procedure, the three-step in vitro procedure, and the NRC 2001 model; and 3) to determine pelleting-induced changes in spectral characteristics of molecular structures of canola meal using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) with univariate and multivariate analysis, and reveal the relationship between molecular structures of protein and carbohydrate and nutrient values, rumen degradation and intestinal digestion characteristics, and predicted protein supply of canola meal. Three different conditioning temperatures (70, 80 and 90ºC) and two different conditioning time (50 and 75 sec) were applied in this research. Two different batches of canola meal from a commercial feed company were selected. A randomized complete block design (RCBD) with 3 × 2 factorial arrangement was employed in this research. Molecular spectral functional groups related to protein, cellulosic compounds, and carbohydrates were used in the spectral study. This research indicated: 1) soluble crude protein (SCP) was decreased and neutral detergent insoluble CP (NDICP) was increased with increasing temperature; 2) the lowest protein rumen degradation of pellets was observed at conditioning temperature of 90 ºC and protein rumen degradation was increased by pelleting; 3) the amount of protein digested in the small intestine tended to increase with increasing conditioning temperature; 4) pelleting under different temperatures and time in the current study shifted the protein digestion site to the rumen, rather than to the small intestine; 5) with respect to predicted protein supply, based on the NRC 2001 model, increasing conditioning temperature tended to increase the metabolizable protein supply of canola meal pellets to dairy cattle; 6) changes in the molecular structure of canola meal induced by pelleting can be detected by ATR-FTIR; 7) not only protein molecular structure characteristics but also carbohydrate molecular structure characteristics play important roles in determining nutrient values, rumen degradation and intestinal digestion characteristics, and the predicted protein supply of canola meal.