Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Dairy Science

First Advisor

Kenneth F. Kalscheur


Canola meal, degradability, digestibility, dairy cattle, corn, barley


Canola meal (CM) is a by-product in the manufacturing process of canola oil which can be performed with or without using solvent extraction. It is a protein supplement which has grown its importance in dairy cattle feeding competing with soybean meal (SBM). However, final quality of the feed depends on the oil extraction process and the production conditions used by the individual processing plant. Two studies were conducted to investigate: 1) the variability among the CM produced in different processing plants and 2) the best starch source or the most suitable proportion of corn and barley to be fed with CM, in order to optimize dairy cattle performance. The first study consisted of an in situ and in vitro experiment where ruminal disappearance kinetics and intestinal digestibility parameters were estimated in seven CM samples obtained from different processing plants located in Canada. Canola meal 5, 6, 7, 9, 10, and 11 were obtained from processing plants using solvent extraction and CM12 was from a plant using mechanically extraction. Disappearance and digestibility parameters for CM were compared with SBM. Ruminal degradation and intestinal digestibility varied significantly among treatments. However, values obtained for degradability and digestibility parameters were in agreement with NRC with slight variations. Data from this study suggests that, variabilities in the chemical composition of CM may be because of the production variabilities occurring during CM manufacturing process in different processing plants. In the second experiment, CM was used as the primarily protein supplement with four different ratios of corn and barley 1) 100:0, 2) 67:33, 3) 33:67, and 4) 0:100. Sixteen multiparous Holstein cows were used in 4×4 Latin square design. Production parameters were not significantly different among treatments. Milk production was averaged for 41.2 kg/d and the efficiency of milk production averaged 1.53. There were no significant differences between the milk protein fractions among treatments. However, ruminal propionate and acetate to propionate ratio varied quadratically. Ruminal pH, NH3-N, and plasma glucose concentration were similar to all treatments. Apparent total tract digestibilities of nutrients (except starch) were linearly decreased as the proportion of barley starch increased in the diet. However, total tract starch digestibility averaged 95.5% and was not affected by varying proportions of corn and barley in the diet. Results of this study concludes that there is no significant effect of starch source on animal performances when CM was used as the major protein source, and similar production responses of feeding corn can be obtained by feeding barley or by mixing corn and barley in different proportions.

Library of Congress Subject Headings

Dairy cattle -- Feeding and feeds
Canola meal as feed
Proteins in animal nutrition


Includes Bibliographic Reference (pages 102-117)



Number of Pages



South Dakota State University


In Copyright - Non-Commercial Use Permitted

18706.pdf (514 kB)