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Canola (Brassica napus) is a crop grown primarily for oil extraction from the seeds. However, this process generates a co-product called canola meal, that is rich in protein. Modifications in the processing of the seeds can affect the meal. The general objective of this research was to reveal the association of intrinsic molecular structures with the nutrient supply to dairy cows from canola seeds and meals from two countries using an advanced vibrational molecular spectroscopy technique, the Fourier transform infrared – Attenuated Total Reflectance (FTIR-ATR). Chapter 1 brings a general introduction of this thesis. And chapter 2 contains the literature review that demonstrates the reasoning and some methods considered when developing this project. Following these, from chapter 3 to chapter 6 each study with its respective results is discussed, and chapter 7 summarizes the whole project. All references are presented on chapter 8 and extra tables and information are brought in the final chapter, chapter 9. In chapter 3, the chemical and nutrient profiles of canola seeds and meals from Canada and China were evaluated. The results showed that DM (dry matter) was higher on Canadian canola meals (89.96 vs. 88.55%, P<0.001) and CP (crude protein) was higher in Chinese meals (43.04 vs. 41.87% DM, P=0.003), but only DM was higher in Canada’s seeds (93.10 vs. 92.28%, P=0.008). Chinese meals presented higher tdNDF (P<0.001) and tdCP (P<0.001), and lower tdNFC (P=0.006) than Canada’s. Only tdNDF of canola seeds was higher in Canada (P=0.023). The soluble fraction (PA2) was higher (P<0.001) in meals from China and the slowly degradable fraction (PB2) was higher (P<0.001) in meals from Canada. Chinese meals and seeds showed higher content of water-soluble carbohydrates (CA4) (P=0.040 and P=0.022, respectively). And Canadian meals presented higher soluble (CB2) and indigestible (CC) fiber contents (P=0.010 and P<0.001). These suggest that although few differences were observed, different procedures in crushing plants affect the meals. Chapter 4 examines the ruminal degradation and intestinal digestibility and provides a characterization of nutrient supplies. From these studies, results showed that the rumen undegradable fraction (U) was higher in Canadian meals (P=0.025) and the rumen degradable fraction (D) was higher in Chinese meals (P=0.016). Also, the hourly degradation of CP was higher in Chinese canola meals on 24 (P=0.042) and 48 hours (P=0.040) of incubation. The in vitro intestinal digestibility showed that the total digestible dry matter and the intestinal digestibility of protein of the canola meals from China were higher (P=0.018 and P=0.016, respectively) than from Canada. The feed milk value (FMV) was determined according to the NRC 2001, DVE/OEB model and based on the energy and no differences were observed for seeds or meals between countries on either method (P>0.05). These results propose that the ruminal and intestinal performance of canola meals and seeds from different companies and countries is similar, as well as the nutrient supply to dairy cows. Chapter 5 is the molecular spectroscopy study of protein and carbohydrate-related structures from canola seeds and meals. Chinese meals showed higher peak heights for total carbohydrate on peaks 3 and 4 (TC3, TC4), cellulosic compounds (CEC), structural carbohydrates (STC2, STC3, and STC4), and areas for TC, CEC, and STC (P<0.05). Canadian canola seeds presented higher peaks for TC1, TC2, TC3, TC4, CEC, STC2, STC4, and TC area (P<0.05), while the ones from China showed a higher peak for SCT1 (P=0.033). Regarding the protein-related structures of canola seeds, they showed no differences between countries (P>0.05). However, the Chinese meals presented higher amide I height; α-helix and β-sheet heights and their ratio; and amide and amide I areas (P<0.05). Principal Component Analysis (PCA) done on the FTIR-ATR analysis was not able to completely differentiate samples from different countries or companies. These results suggest that the canola seeds and meals processed in Canada are comparable to those processed in China. Chapter 6 describes the relationship between the molecular structures spectra features of canola seeds and meals and nutrient utilization and availability to dairy cows. The results from the correlation study showed that the area of structural carbohydrate (STCA) commonly appears to be related to meals’ characteristics and total carbohydrate area (TCA) to features of the seeds. The amide region showed a strong relationship with nutritional characteristics of both seeds and meals. These results indicate that the carbohydrate and protein structures studied with FTIR-ATR are related to canola seeds and meals’ chemical and nutrient profiles, as well as rumen degradable and intestinal digestibility characteristics. In conclusion, canola seeds processed in crushing plants in Canada mostly presented the same characteristics and behaviors as the seeds processed in China; although canola meals presented some differences in the chemical and nutrient profiles, they provide similar nutrient supply and utilization to dairy cows; and the FTIR-ATR technique applied on the samples to study protein and carbohydrate-related structures proved to an efficient method to predict chemical, degradable and digestible characteristics of canola meals and seeds.



Brassica napus, canola, spectroscopy, dairy cows



Master of Science (M.Sc.)


Animal and Poultry Science


Animal Science


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