Effects of canola meal pellet conditioning temperature and time on ruminal and intestinal digestion, hourly effective degradation ratio, and potential nitrogen to energy synchronization in dairy cows

Abstract

The increase in bio-oil production in North America has resulted in millions of tonnes of co-products: canola meal and carinata meal. Little research has been conducted to determine the effect of pellet conditioning temperature, time, and their interaction on processing-induced changes in nutrient digestibility in the rumen and intestine (in vitro) of dairy cattle. The objectives of this study were to investigate the effects of conditioning temperature (70, 80, and 90°C), time (50 and 75 s), and their interaction (temperature × time) during the pelleting of canola meal on (1) rumen degradation kinetics and effective rumen degradability of dry matter, crude protein (CP), and neutral detergent fiber; (2) intestinal digestibility of rumen-undegradable protein (RUP); and (3) hourly effective rumen degradation ratio and potential N to energy synchronization in dairy cattle. The results showed that the temperature and duration of pellet conditioning significantly altered the degradation characteristics of nutrients in the rumen. Pelleting increased CP degradation in the rumen, and CP digestion site was shifted to the rumen rather than to the small intestine. When conditioning temperature was set 80°C, the rumen degradation of CP and neutral detergent fiber was highest, but postrumen digestion was lowest. With respect to intestinal digestion, the available CP for intestinal digestion became less because of reduced RUP supply to the small intestine. The pelleting process tended to significantly affect the intestinal digestibility of RUP. However, the total digestible CP content of canola meal was not affected. In conclusion, pelleting induced changes in rumen and intestinal digestion profiles, and altered the potential N to energy synchronization and hourly effective rumen degradation ratio of canola meal in dairy cattle.

Structural changes on a molecular basis of canola meal by conditioning temperature and time during pelleting process in relation to physiochemical (energy and protein) properties relevant to ruminants

“…The pelleting conditions and sample preparation were reported previously [ 11 ] as follow: “The co-product from bio-oil processing—canola meal were used in this study to investigate on the effect of conditioning temperature, time and their interaction of pelleting process on internal protein structure changes on a molecular level in relation to nutrient nutritional value in dairy cattle. Two representative sources of the co-product were obtained from Federated Cooperatives Limited (Saskatoon, SK, Canada) with different manufacturing dates.…”

“…Detailed chemical analyses were reported previously [ 11 , 12 ] as follow: “For chemical analyses, all samples were ground through a 1 mm screen using a Retsch ZM 200 Rotor mill (Rose Scientific Ltd., Edmonton, AB, Canada). Dry matter (DM), ash, ether extract (EE), and crude protein (CP) were analyzed according to AOAC official methods 930.15, 942.05, 954.02, and 984.13, respectively.…”

“…All samples were incubated with a bicarbonate-phosphate buffer, then filtered through the Whatman #54 filter papers to determine the total soluble crude protein (SCP) content [ 32 ]. The method used to determine non-protein nitrogen (NPN) was in accordance with Licitra et al [ 31 ], in which tungstic acid is used to precipitate the true protein fraction and then the difference between total crude protein and precipitated crude protein is considered the NPN.” The detailed chemical profiles and PDI changes induced by different conditioning temperatures and time of pelleting process were reported previously [ 11 , 12 ]. These data were used for relationship study between pelleting induced molecular structural changes in relation to predicted protein and energy values in dairy cattle.…”

“…Detailed methods were reported previously [ 11 , 12 ] as follow: “summative approaches from the National Research Council [ 33 ] dairy were used to estimate values of the total digestible non-fiber carbohydrates (tdNFC), the total digestible crude protein (tdCP), the total digestible neutral detergent fiber (tdNDF), the total digestible fatty acid (tdFA), the total digestible nutrients at 1× maintenance (TDN 1x ), the total digestible nutrients at 3× maintenance (TDN 3x ), the digestible energy (DE 1x ), the digestible energy at the production level of 3×maintenance (DE p3x ), the metabolizable energy at the production level of 3× maintenance (ME p3x ), and the net energy at the production level of 3× maintenance (NE Lp3x ). The methods to determine the metabolizable energy (ME), the net energy for maintenance (NE m ) and the net energy for gain (NE g ) were in accordance with NRC [ 33 ].” The energy value changes induced by different conditioning temperatures and time were reported previously [ 11 , 12 ]. These data were used for relationship study between pelleting induced molecular structural changes in relation to predicted protein and energy values in dairy cattle.…”

“…Recently we reported the effects of canola meal pellet conditioning temperature and time on ruminal and intestinal digestion, hourly effective degradation ratio, and potential nitrogen to energy synchronization in dairy cows [ 11 ]. However, no systematical study was conducted to determine how the pelleting at different conditioning temperature and time induce the changes in protein intrinsic molecular structures in the co-products and how these molecular structure changes affect energy and protein utilization in dairy cows.…”