Advances in dairy Research
Open Access

Canola Meal as a Feed Ingredient for Lactating Dairy Cows: A Review

Essi Evans^1* and Brittany Wood^{2 *}Correspondence: Essi Evans, Department of Nutrition, Essi Evans Technical Advisory Services Inc., Bowmanville, ON, Canada, Email:

Author info »

Introduction

Canola is derived largely from Brassica napus (95%), with the remaining portions from Brassica rapa and Brassica juncea seed [1]. Canola differs from rapeseed by having been bred through traditional plant breeding techniques to contain very low levels of the two most prominent anti nutritional factors erucic acid and glucosinolates. Rapeseed with low levels of these anti nutrients is often referred to as “canola quality” rapeseed, or double low rapeseed. True canola is produced in Canada and Australia. Canola meal and canola-quality rapeseed meals are the residues remaining after the highly prized oil are extracted from seeds. Canola meal, along with its parent crop rapeseed meal, ranks second with respect to protein meals traded globally [1,2]. The nutrient compositions of canola meal from Canada and Australia along with European canola-quality rapeseed meal are provided in Table 1.

Table 1: Nutrient composition of Canadian and Australian solvent extracted canola meal and European 00 rapeseed meal (DM basis) ^1,2,3

Canola meal is a relatively new and evolving ingredient, and the bulk of the relevant research with respect to contemporary dairy production has been conducted in the last 15 years. The purpose of this review is to highlight the true feeding value of canola meal and to dispel misconceptions regarding this meal that persist from earlier research, testing varieties of the meal that are no longer available, and not tested with cows with lower levels of milk production. Most of the research referenced in this review relates to Canadian solvent extracted canola meal.

Literature Review

Canola meal palatability

Canola meal is a highly palatable ingredient for adult ruminant animals. Many recent studies have revealed that intakes in dairy cows can be maintained or enhanced when canola meal replaces soybean meal or distillers’ grains. In a Latin Square designed study, provided dairy cows with diets containing 0, 8, 16 or 24 percent canola meal, replacing soybean meal [3-7]. Dry Matter (DM) intakes increased linearly with canola meal inclusion contributing to greater milk yield (Table 2). Broderick and Faciola replaced 8.7% of soybean meal with 11.7% canola meal [8]. Cows consumed 0.5 kg more DM with the canola meal diet. Substituted 20.8% canola meal in replacement of 13.7% soybean meal, with cows consuming 23.6 and 24.0 kg of DM for the two diets, respectively [9]. Fed up to 20% of DM as canola meal to high-producing cows in exchange for high-protein distillers’ grains, with no reduction in Dry Matter Intake (DMI) [10]. Three early lactation trials [11-13] noted a onekg increase in intake when canola meal replaced soybean meal in the diet. Heim and Krebs suggested that solvent extracted canola meal may be more palatable than expeller canola meal. Solvent extracted meal is more readily available on the North American market [1,14].

Table 2: Effect of increasing dietary canola meal on dry matter intake¹.

Protein value of canola meal

Amino acid composition: Canola meal has been recognized as the star of all vegetable proteins due to the meal’s superior amino acid profile. A quarter century ago, Shingoethe demonstrated that the amino acid profile of canola meal matched the needs of dairy cows for milk yield (Table 3) and complemented rumen microbial protein to a greater degree than other vegetable proteins [15]. This was recently underscored by Kuehnl and Kalscheur who examined the effect of amino acids in early lactation and showed that the efficiency of amino acid utilization was superior for canola meal [16]. The amino acid composition of the intact meal and the Rumen Undegraded Protein (RUP) fraction of the meal are provided in Table 4. These values were determined by Ross based on the RUP method developed [6,17]. The samples were a subset of a survey of samples obtained between 2011 and 2014 from 13 processing plants across Canada [18-20].

Table 3: Milk protein score system used to compare proteins (1.00 = perfect) ¹

Table 4: Essential amino acid composition of canola meal and canola meal RUP fraction as determined by Cornell University using the Ross method^{1, 2}.

Rumen under graded protein in canola meal: While the amino acid profile contributes greatly to the importance of canola meal in ruminant feeds systems, equally so does the RUP component of the meal. Approximately half of the protein in canola meal is in the form of RUP, an amount greater than that found for solvent extracted soybean meal (Table 5) [5,6,12,21-23].

Table 5: The RUP value for canola meal and soybean meal, as determined by newer methods of analysis (% of total protein).

The in-situ nylon bag method was the standard procedure used to partition feed protein into RUP and Rumen Degraded Protein (RDP fractions) in early studies. The error in this method resides in the fact that soluble protein, along with protein that becomes soluble and leaves the porous bags are presumed to be completely degraded by the microbes in the rumen, and therefore unavailable as an amino acid source for the cow. Indeed, so entrenched is the notion that solubility and degradation are equal, that the recently released NASEM did not update this concept since the last publication where the inaccuracy was mentioned. Errors in estimating how feed proteins are partitioned hamper the ability of feed formulators to ensure nutrient availability to support optimum rumen microbial growth, as well as to accurately determine the amounts of amino acids entering the intestine from microbial and feed ingredient sources [18,19].

The actual rumen degradability of soluble protein is highly variable and has long been described as such. The degradation of protein and amino acids results in the release of ammonia nitrogen in the rumen. Determined that the amount of ammonia generated under in vitro conditions indicated that peptides and amino acids can accumulate [21-24]. The authors clearly stated “a portion of the soluble protein may require some disruption of secondary and tertiary structure for proteolysis to proceed. Proteins with extensive disulfide bonding, such as albumins or immunoglobulins, or those containing artificial cross-links caused by chemical treatment, are more slowly degraded than less ordered proteins”.

Proteins that are rich in disulfide bonds are soluble, but resistant to degradation in the rumen [25,26] The two major storage proteins in canola meal are napin, an albumin protein and cruciferin, a globulin protein [27].Both proteins can readily become soluble, with napin highly likely to become soluble under rumen conditions [28]. In the case of canola meal, with napin rich in disulfide bonds, the degradability of soluble protein is less than some other common vegetable proteins.

Table 6 references examples of true degradation rates for the soluble fraction of proteins as determined by Hedqvist and Udén [20]. The soluble protein in canola meal is broken down much more slowly than the soluble protein in the remaining test ingredients except for flax meal, resulting in considerable opportunity for the soluble fraction from canola meal to reach the intestine. Adding to this the fact that soluble protein exits the rumen with the liquid outflow, which is at least twice as fast as the solid turnover rate [29].

Table 6: Rates of digestion of the soluble fraction of protein in the rumen for selected ingredients¹

Rumen under graded protein in canola meal: Using direct measurement of abomasal nitrogen flow, both determined that there were no differences in microbial protein yield when canola meal was used to replace soybean meal as a source of protein [30,31]. Results from two feeding trials using urinary purine derivatives to estimate microbial protein yield found no differences in the two sources of protein, while using the same methodology found that the canola meal diet promoted rumen conditions to improve microbial growth [32-34]. Determined that there were no differences in microbial protein yield for soybean meal or canola meal diets in a dual flow fermentation study [35].

In a different experimental model in which heat-treated canola meal was substituted for barley, rumen microbial growth was decreased with higher levels of canola meal. Increasing concentrations of heat-treated canola meal resulted in greater amounts of rumen escape protein and lesser amounts of rumen microbial protein [36]. However, by substituting heat-treated canola meal for barley in the diets the level of available starch needed to support microbial growth was reduced.

Energy value of canola meal

Like most concentrate ingredients, canola meal is a good source of energy, providing nutrients for rumen microbial growth, and supporting animal productivity. In the past, the energy in canola meal has been undervalued and remains in error in many publications mainly resulting from the underestimation of Neutral Detergent Fiber (NDF) digestibility [19,37]. Several popular feed formulation programs use multiples of lignin percentage to discount the digestibility of the cell wall. Using lignin, NRC estimated unavailable NDF in canola meal approached 65%, with the potentially available NDF estimated at 35% [19]. Using a newly developed indigestible NDF assay, demonstrated that the unavailable NDF in canola meal was 32% of the total NDF after 120 hours of rumen incubation, and that the potentially digestible cell wall was therefore 68% [38]. Again, actual digestibility would be lower due to potentially digestible cell wall exiting the rumen before digestion is complete. The recently released NASEM system, which recommends a 48-hour NDF digestibility determination, is more accurate and provides a more realistic energy value than the previous calculation from lignin [18].

Based on the results of a 4-year survey of 12 canola processing plants (144 samples), determined that NDF digestibility at 288 hours of rumen incubation to be 80.2% of NDF and estimated actual rumen digestibility at 3 times maintenance intake to be 60.2% [39]. In a follow up to this, determined that the calculated Net Energy of Lactation (NE-L) at 3 times maintenance intake would be 1.87 Mcal/kg [40]. These results corroborate with some older studies that show that approximately half of the NDF is truly digested in lactating dairy cows [41,42].

In a study comparing distillers’ grains, high-protein distillers’ grains, soybean meal and canola meal, there were no differences in energycorrected milk/DM or changes in body condition score that could be associated with the protein sources [43]. Saw no differences in DMI or body condition score when up to 20% canola meal replaced high-protein corn distillers’ grains [10]. Energy output in milk was higher with the diets containing canola meal, indicating that the energy value of canola meal was at least as great as the high protein distillers’ grains. Built on these newer results, the average energy values for canola meal provided in Table 7.

Table 7: Average energy values for solvent extracted and expeller canola meal ^1,2.

Canola fatty acids

Solvent extracted canola meal of Canadian origin tends to contain somewhat higher fat than many other oilseed meals, and this fat contributes to the energy value of the meal. This highly unsaturated source of fatty acids is made up largely of the mono-unsaturated fatty acid, oleic acid (C18:1).

Unsaturated fatty acids in the rumen have the potential to allow the accumulation of bio hydrogenation intermediates that can interfere with milk fat synthesis and result in milk fat depression. Oleic acid is less likely to produce the fatty acid intermediates that contribute to milk fat depression than the fatty acids with 2 or more unsaturated bonds. In a meta-analysis, Dorea and Armentano determined that feed ingredients with oils containing predominately linoleic acid (C18:2) were twice as likely to reduce milk fat as those containing mainly C18:1 or linolenic acid (C18:3). Oilseeds with higher C18:1 concentrations are likely to increase milk fat concentration and yield as well as the C18:1 content of milk indairy cows, compared with oils containing C18:2 [44,45].

He and Armentano added large amounts of vegetable oils (5% of DM) varying in fatty acid composition to the diet of lactating cows [46]. Fat yield declined from 1.14 kg/cow/day to 1.02 kg/cow/day for the diets with the added C18:1 and linoleic acid (C18:3) but fell to 0.86 kg/cow/day with linoleic acid (C18:2). In a follow up study, again with high concentrations of added fat, determined that C18:2 was a more potent fatty acid than C18:1 for causing milk fat depression [47]. Provided cows with experimental diets differing in fatty acid composition, but the added fat sources were provided at levels that would be typical of practical feeding situations [48]. The effects on milk fat percentage and milk fat yields were strikingly different for the diets. Milk fat yield was 1.44 kg/cow/day with the high C18:1 diet as compared to 1.31 kg/cow/day for the high C18:2 diets. Fat yield with the low oil control diet was 1.41 kg/ cow/day, indicating that the diet with greater levels of C18:1 did not impact milk fat yield when provided at normal feeding levels.

Furthermore, the common unsaturated fatty acids (C18:1, C18:2 and C18:3) can interfere with microbial metabolism by destabilizing the cell membrane, increasing the permeability of the membrane [49]. This effect is greatest as the number of double bonds increases (C18:3>C18:2>C18:1).

In contrast, some studies have indicated that rumen digestibility increases with C18:1 added approximately 6.5% canola oil (62% C18:1) into diets for late lactation cows and evaluated ruminal digestibility [50]. As Table 8 shows, rumen digestibility values were greater for the diet to which the canola oil had been added. Prom and Lock found that added oleic acid improved rumen DM and NDF digestibility [51].

Table 8: Rumen digestibility of nutrients by cows receiving supplemental canola oil ¹.

The rate of bio hydrogenation of C18:1 has been shown to be lower than the more saturated fatty acids [52] resulting in greater rumen escape of this fatty acid. Unlike other C18 fatty acids, C18:1 has been shown to act as an amphiphilic agent and improve nutrient digestibility [53,54]. Compared diets containing conventional (high C18:2) soybean meal to a genetically modified high C18:1 soybean meal variety [45]. Total tract digestibility was greater with the high C18:1 meal. The only difference in the diets was the composition of the fatty acids. In another study infusing C18:1 into the abomasum improved fatty acid digestibility [55].

Micronutrients in canola meal

Phosphorus: Canola meal is a rich source of phosphorus, with most of this mineral in the form of phytate phosphorus. Unlike monogastric animals, this form is available to ruminants, due to the presence of bacterial phytases in the rumen that rapidly degrade phytate [56].

Iodine: Cruciferous plants such as canola and rapeseed contain glucosinolates that reduce iodine uptake by the thyroid gland and mammary gland [57]. While levels of glucosinolates are extremely low in current day canola meal and double zero rapeseed meal, several studies have shown that milk iodine concentrations are reduced when these protein sources are provided at higher levels of intake [58,59]. Cows with diets containing 0, 6, 14 or 20% expeller rapeseed meal, which contained a total of 1.07 μ mol/g of glucosinolates [59]. They determined that the proportion of iodine consumed that was transferred to milk was 25, 19, 13 and 10% for the four respective diets. The benefit of this was shown in a study [60]. Feeding 13.9% canola meal in the test diet and 2.0 mg of iodine resulted in milk iodine levels that were close to that found when 0.5 mg/kg of iodine was provided in diets where canola meal was excluded. However, blood serum iodine concentrations were much higher with canola meal (Table 9) and this would permit the benefits of higher iodine inclusion to be manifested, without producing unacceptable levels of iodine in milk.

Table 9: Effects of feeding canola meal on iodine concentrations in blood serum and milk (ug/L)¹.

Dietary cation anion difference: The Dietary Cation Anion Difference of the diet (DCAD) provides a calculation of the difference between the major cations (sodium and potassium) and anions (sulfur and chlorine) in the diet. When there are equal amounts of these on a molecular basis, then the diet is neutral. It is considered desirable to have excess anions in the close-up dry period, as this may be beneficial in reducing the incidence of milk fever at calving. The sudden drain on blood calcium when lactation begins must be offset by greater calcium absorption as well as mobilization of calcium from bone. Negative DCAD diets have been shown to help maintain blood calcium levels by assisting in the release of calcium from bone.

Erdman and Iwaniukdemonstrated that canola meal, unlike many other grains and protein meals, has a negative DCAD value (-76 mEq/kg DM), which can be beneficial when formulating diets for this parameter, reducing the need for often unpalatable anionic salts [61].

Antioxidants: Oxidative stress is a common occurrence in the transition period, and during heat stress. Canola meal contains a variety of antioxidants, including phenolic compounds, vitamin E and carotinoids [62-64].These may contribute to the reduction of free radical compounds and concomitant cellular damage produced by them.

Feeding canola meal to lactating cows

Meta-analyses of feeding value: There have been five in-depth meta-analyses conducted since 2011 in which canola meal was compared to other vegetable proteins in diets for lactating dairy cows. Evaluated results from 122 studies where supplemental protein was supplied by either soybean meal or canola meal [65]. In all trials, the added protein replaced grain and the forages were kept constant. The analysis revealed that for each kg increase in crude protein consumed, milk production increased by 3.4 kg with canola meal and 2.1 kg with soybean meal. The researchers concluded that canola meal was undervalued when compared to soybean meal.

Using different data selection criteria, compared the effects of replacing vegetable proteins in the diet with the same amount of protein from canola meal [66]. Results from 27 published studies, evaluating 88 treatments were included in the analysis. At the average inclusion level (2.3 kg per day) of canola meal, milk yield was 1.4 kg greater.

In a continuation of the previous meta-analysis, compared the response in plasma amino acids to changes in the protein source in the diet [67]. Results from 10 feeding experiments and 21 treatment comparisons were available. Plasma essential amino acid concentrations were higher and milk urea nitrogen was lower when cows received canola meal compared to all other sources of protein. The conclusion from this report was canola meal increased the availability of essential amino acids.

Collected data from 37 peer-reviewed manuscripts evaluating the use of canola meal to replace other vegetable protein sources [68]. Mean treatment differences were compared in this analysis. Differences attained significance for all values shown in Table 10.

Table 10: Meta-analysis of the use of canola meal in diets for dairy cows [68]

To incorporate some more recent research findings, conducted a final meta-analysis to compare feeding results from studies limited to those in which canola meal was compared to another protein in full and in part [69]. Several research studies have shown that mixing other vegetable proteins with canola meal enhances the value of the non-canola protein source, but it was not clear if the non-canola proteins enhanced the value of canola meal. This comprehensive study indicates that blending other vegetable proteins with canola meal will not improve milk production. The study also showed that canola meal can be provided in diets up to 19% of the DM, the highest level tested at the time data were collated, with no losses in milk production, and no negative effect upon intake [70-75].

Canola meal in early lactation: Only recently have trials been conducted to evaluate canola meal for cows in early lactation. Since 2016, there have been four research studies that support the utilization of canola meal in diets for dairy cows in early lactation (Table 11). All trials showed that cows given canola meal produced greater yields of milk. Feed efficiency values were similar for both protein sources, with one exception where there was a significant advantage for the canola meal diet [11,76-80].

Table 11: Performance of cows receiving canola meal or soybean meal in early lactation.

Although there were no differences in feed efficiency in the experiments conducted and showed lower losses in body condition when cows received the diets containing canola meal. Both were large herd studies conducted under actual farm conditions [34,13].

Mid lactation feeding trials: Tables 12 and 13 show the milk yield results for head-to-head studies that have been published in recent times comparing canola meal to other common vegetable protein sources. Most of the trials involved comparing canola meal to soybean meal, although there have been trials involving other proteins As the results illustrate, canola meal performed as well or better than the alternative meals evaluated for milk production potential in most published studies [81-89].

Table 12: Comparison of milk production (kg) by cows where the major supplemental protein was provided by canola meal or soybean meal.

Table 13: Comparison of milk production (kg) by cows where the major supplemental protein was provided by canola meal or another vegetable protein.

Discussion

Using canola meal to reduce greenhouse gas emissions

Several recent studies have indicated that canola meal may have application in diets to reduce emissions in lactating Holstein dairy cows and can provide a potentially economical mechanism for lowering enteric methane and output, the two greenhouse gases of greatest importance to livestock production [86,87].

Enteric methane production can be expressed in several ways. The first is amount/animal/day. This is influenced by the size (Jersey vs. Holstein as an example) or maturity of the animal, as well as level of production. Another measurement used is methane/unit of feed consumed. This metric is useful for analyzing the portion of the total gross energy lost under defined conditions, as is referred to as methane yield. Methane intensity is a measure of methane output/ unit of meat or milk produced [88-90].

Table 14 provides results from recent studies where canola meal was used to replace soybean meal as a protein source in experimental rations. Only one trial was available with Jersey cows, and the inclusion of 10.1% CM in that study did not reduce methane output, as determined using the indirect calorimetry method [90].

Table 14: Comparison of methane output for diets in which canola meal replaced soybean meal as the primary source of protein.

The results show that on average Energy Corrected Milk (ECM) was increased by 1.0 kg/cow/day, while methane was reduced by 5.0, 7.5 and 8.6 percent when expressed as grams/day, yield or intensity, respectively [7,32,74,90,93,94].

There are many factors that influence the extent to which enteric methane output is reduced by the inclusion of canola meal in the diet, such as the forage sources or the forage to concentrate ratio. The level of canola meal inclusion appears to be a factor as well. In a recent experiment cows received 16% crude protein diets that varied from 0%-24% canola meal [7]. As Table 4 shows, methane output was reduced as the level of inclusion increased.

Part of the methane reduction value of canola meal can be associated with the lipid profile, which is rich in oleic acid. Lipids can reduce enteric methane in three ways: by directly targeting methanogens and protozoa, by acting as a reservoir for H+, and by providing a concentrated source of energy. Unsaturated fatty acids can bind to protozoa cell membranes and inhibit the transport of H+ by protozoa to methanogens [91]. The biohydrogenation of unsaturated fatty acids likewise provides a hydrogen sink, resulting in less H+ available in the rumen to produce methane. A metaanalysis revealed that methane was reduced by 2.2% for each 1% addition of lipid to the diet of dairy cows. Similarly, found that dietary lipids reduced methane by 5.6% for each 1% lipid added to diets for beef cattle [92].

The reduction in methane that occurs with the feeding of canola meal is only partially related to the contribution of the lipid fraction determined that when canola, flax or sunflower oil were added to diets already containing canola meal, all supported reduced methane output, demonstrating additivity between the meal and oil fractions [86,93,94]. Furthermore, found that the fermentation of canola meal increases propionate, resulting in less one carbon moieties available to contribute to gas production [95]. These researchers were able to identify a high negative correlation between the slowly degraded protein fraction of CM (-0.99) and methane. They additionally correlated reduced methane with fat content of the meal (-0.80) determined that tannins can likewise reduce methane, with the effect being additive to the effects of fat [96]. The seed hull of canola is a notable source of tannins (Table 15).

Table 15: Relationship between the level of inclusion of canola meal in the diet and methane output as determined in one study ¹

Additionally, canola meal has been shown to reduce nitrous oxide output by dairy cows. Many research papers, as described in two recent meta-analyses have shown that the efficient use of absorbed protein results in lower blood urea nitrogen when compared to other vegetable protein meals [66,69]. Excreted urea nitrogen is rapidly converted to ammonia gas, which can thereby indirectly contribute to atmospheric nitrous oxide. As Table 16 illustrates, urine nitrogen excretion is reduced and milk nitrogen (protein) is elevated as canola meal in the diet is increased [96]. Modifying the level of canola oil in diets containing canola meal did not alter nitrous oxide production [89].

Table 16: Effect of increasing canola meal on the diet on urinary nitrogen excretion ¹

Conclusion

Feed represents a large part of the cost of dairy production. Selection of ingredients for inclusion in diets for dairy cows therefore requires careful consideration with respect to costs, nutrient delivery and cow performance. The data provided herein should assist nutritionists and feed formulators in determining the advantages or disadvantages of including canola meal in diets for lactating dairy cattle.

Disclosures

Competing interests

The authors have no competing interests.

Funding

Not applicable.

Author’s contributions

EE Gathered available literature and prepared the first draft. BW revised the manuscript and added information. EE and BW prepared the final draft and approved the final manuscript prior to submission.

Acknowledgements

Not applicable

References

1. Canola Meal Feeding Guide. Canola Council of Canada. 2019.

   [CrossRef] [Google Scholar] [PubMed]

2. Bernard JK. Oilseed and oilseed meals. 2019.

   [CrossRef] [Google Scholar]

3. Australian Canola Meal Guide for the Feed Industry . Australian Oilseed Federation. 2014.
4. INRAE-CIRAD Feed Tables. 2000.
5. Broderick GA, Colombini S, Costa S, Karsli MA, Faciola AP. Chemical and ruminal in vitro evaluation of Canadian canola meals produced over 4 years. J Dairy Sci. 2016; 99(10):7956-7970.

   [CrossRef] [Google Scholar] [PubMed]

6. Ross, D. Personal communication. 2015.
7. Benchaar C, Hassanat F, Beauchemin KA, Gislon G, Ouellet DR. Diet supplementation with canola meal improves milk production, reduces enteric methane emissions, and shifts nitrogen excretion from urine to feces in dairy cows. J Dairy Sci. 2021; 104(9):9645-9663.

   [CrossRef] [Google Scholar] [PubMed]

8. Broderick, GA and Faciola, AP. Effects of supplementing rumen-protected methionine and lysine on diets containing soybean meal or canola meal in lactating dairy cows. J Dairy Sci.2014; 97 (Suppl 1):750-751.

   [CrossRef]

9. Maxin G, Ouellet DR, Lapierre H. Effect of substitution of soybean meal by canola meal or distillers grains in dairy rations on amino acid and glucose availability. J Dairy Sci. 2013; 96(12):7806-7817.

   [CrossRef] [Google Scholar] [PubMed]

10. Swanepoel N, Robinson PH, Erasmus LJ. Determining the optimal ratio of canola meal and high protein dried distillers grain protein in diets of high producing Holstein dairy cows. Anim Feed Sci Technol. 2014.

    [CrossRef] [Google Scholar]

11. Moore SA, Kalscheur KF. Canola meal in dairy cow diets during early lactation increases production compared with soybean meal. J Dairy Sci. 2016.

    [CrossRef] [Google Scholar]

12. Gauthier H, Swanepoel N, Robinson PH. Impacts of incremental substitution of soybean meal for canola meal in lactating dairy cow diets containing a constant base level of corn derived dried distillers’ grains with solubles. Anim Feed Sci Technol. 2019.

    [CrossRef] [Google Scholar]

13. Kuehnl JM, Kalscheur, KF. Production and temporal plasma metabolite effects of soybean meal versus canola meal fed to dairy cows during the transition period and early lactation. J Dairy Sci. 2021.
14. Heim R, Krebs G. Utilisation of canola meal as protein source in dairy cow diets: A review. Agric Nat Resour. 2020; 54(6):623-632.

    [Google Scholar]

15. Schingoethe DJ. Balancing the amino acid needs of the dairy cow. Anim Feed Sci Technol 1996; 60(3-4):153-160.

    [CrossRef] [Google Scholar]

16. Kuehnl, J.  Kalscheur, K. Canola meal enhances early lactation milk production. Hoard's Dairyman. 2022.
17. Ross DA, Gutierrez-Botero M, Van Amburgh ME. Development of an in vitro intestinal digestibility assay for ruminant feeds. In Proceedings of the cornell nutrition conference 2013.  

    [Google Scholar]

18. NASEM. Nutrient Requirements of Dairy Cattle. National Research Council, National Academies Press, Washington, D.C. 2021.  

    [Google Scholar]

19. NRC. Nutrient Requirements of Dairy Cattle. National Research Council, National Academies Press, Washington, D.C. 2001.  

    [Google Scholar]

20. Hedqvist H, Udén P. Measurement of soluble protein degradation in the rumen. Anim Feed Sci Technol. 2006; 126(1-2):1-21.

    [CrossRef] [Google Scholar]

21. Jayasinghe, NK. Kalscheur, KF, Anderson,JL,  Casper, DP. Ruminal degradability and intestinal digestibility of protein and amino acids in canola meal. J Dairy Sci. 2014.
22. Maxin G, Ouellet DR, Lapierre H. Ruminal degradability of dry matter, crude protein, and amino acids in soybean meal, canola meal, corn, and wheat dried distillers grains. J Dairy Sci. 2013; 96(8):5151-5160.

    [CrossRef] [Google Scholar] [PubMed]

23. Tylutki TP, Fox DG, Durbal VM, Tedeschi LO, Russell JB, Van Amburgh ME, et al. Cornell net carbohydrate and protein system: A model for precision feeding of dairy cattle. Anim Feed Sci Technol. 2008; 143(1-4):174-202.

    [CrossRef] [Google Scholar]

24. Broderick GA, Wallace RJ, Ørskov ER. Control of rate and extent of protein degradation. In Physiological aspects of digestion and metabolism in ruminants. 1991.

    [CrossRef] [Google Scholar]

25. Wallace RJ. Hydrolysis of 14C-labelled proteins by rumen micro-organisms and by proteolytic enzymes prepared from rumen bacteria. Br J Nutr. 1983; 50(2):345-355.

    [CrossRef] [Google Scholar] [PubMed]

26. McNabb WC, Spencer D, Higgins TJ, Barry TN. In‐vitro rates of rumen proteolysis of ribulose‐1, 5‐bisphosphate carboxylase (rubisco) from lucerne leaves, and of ovalbumin, vicilin and sunflower albumin 8 storage proteins. J Sci Food Agric. 1994; 64(1):53-61.

    [CrossRef] [Google Scholar]

27. Perera SP, McIntosh TC, Wanasundara JP. Structural properties of cruciferin and napin of Brassica napus (canola) show distinct responses to changes in pH and temperature. Plants. 2016.

    [CrossRef] [Google Scholar] [PubMed]

28. Chmielewska A, Kozłowska M, Rachwał D, Wnukowski P, Amarowicz R, Nebesny E, et al. Canola/rapeseed protein–nutritional value, functionality and food application: A review. Crit Rev Food Sci Nutr. 2021; 61(22):3836-3856.

    [CrossRef] [Google Scholar] [PubMed]

29. Seo S, Tedeschi LO, Lanzas C, Schwab CG, Fox DG. Development and evaluation of empirical equations to predict feed passage rate in cattle. Anim Feed Sci Technol. 2006; 128(1-2):67-83.

    [CrossRef] [Google Scholar]

30. Brito AF, Broderick GA, Reynal SM. Effects of different protein supplements on omasal nutrient flow and microbial protein synthesis in lactating dairy cows. J Dairy Sci. 2007; 90(4):1828-1841.

    [CrossRef] [Google Scholar] [PubMed]

31. Paula EM, Broderick GA, Danes MA, Lobos NE, Zanton GI, Faciola AP. Effects of replacing soybean meal with canola meal or treated canola meal on ruminal digestion, omasal nutrient flow, and performance in lactating dairy cows. J Dairy Sci. 2018;101(1):328-339.

    [CrossRef] [Google Scholar] [PubMed]

32. Lage CF, Räisänen SE, Stefenoni H, Melgar A, Chen X, Oh JO, et al. Lactational performance, enteric gas emissions, and plasma amino acid profile of dairy cows fed diets with soybean or canola meals included on an equal protein basis. J  Dairy Sci. 2021;104(3):3052-3066.

    [CrossRef] [Google Scholar] [PubMed]

33. 33. Pereira AB, Moura DC, Whitehouse NL, Brito AF. Production and nitrogen metabolism in lactating dairy cows fed finely ground field pea plus soybean meal or canola meal with or without rumen-protected methionine supplementation. J Dairy Sci. 2020;103(4):3161-3176.

    [CrossRef] [Google Scholar] [PubMed]

34. 34. Swanepoel N, Robinson PH, Conley A. Impacts of substitution of canola meal with soybean meal, with and without ruminally protected methionine, on production, reproduction and health of early lactation multiparous Holstein cows through 160 days in milk. Animal Feed Sci Technol. 2020;264:114494.

    [CrossRef] [Google Scholar]

35. Paula EM, Monteiro HF, Silva LG, Benedeti PD, Daniel JL, Shenkoru T, et al. Effects of replacing soybean meal with canola meal differing in rumen-undegradable protein content on ruminal fermentation and gas production kinetics using 2 in vitro systems. J Dairy Sci. 2017;100(7):5281-5292.

    [CrossRef] [Google Scholar] [PubMed]

36. Krizsan SJ, Gidlund H, Fatehi F, Huhtanen P. Effect of dietary supplementation with heat-treated canola meal on ruminal nutrient metabolism in lactating dairy cows. J Dairy Sci. 2017;100(10):8004-8017.

    [CrossRef] [Google Scholar] [PubMed]

37. National Research Council. Nutrient requirements of beef cattle. National Research Council. Subcommittee on Mineral Toxicity in Animals. National Academy of Science. Washington DC. 1996:234.
38. Cotanch KW, Grant RJ, Van Amburgh ME, Zontini A, Fustini M, Palmonari A, et al. Applications of uNDF in ration modeling and formulation. Proceed Cornell Nutr Conf.2014: 114-131.

    [Google Scholar]

39. Paula EM, Daniel LP, Silva LG, Costa HH, Faciola AP. Assessing potentially digestible NDF and energy content of canola meal from twelve Canadian crushing plants over four production years. J Dairy Sci. 2017;100:329-340.

    [Google Scholar]

40. Arce-Cordero JA, Paula EM, Daniel JL, Silva LG, Broderick GA, Faciola AP. Effects of neutral detergent fiber digestibility estimation method on calculated energy concentration of canola meals from 12 Canadian processing plants. J Anim Sci. 2021;99(11):309.

    [CrossRef] [Google Scholar] [PubMed]

41. Mustafa AF, Christensen DA, McKinnon JJ. Chemical characterization and nutrient availability of high and low fiber canola meal. Canadian J Anim Sci. 1996;76(4):579-586.

    [CrossRef] [Google Scholar]

42. Mustafa AF, Christensen DA, McKinnon JJ. The effects of feeding high fiber canola meal on total tract digestibility and milk production. Canadian J Anim Sci. 1997;77(1):133-140.

    [CrossRef] [Google Scholar]

43. Christen KA, Schingoethe DJ, Kalscheur KF, Hippen AR, Karges KK, Gibson ML. Response of lactating dairy cows to high protein distillers grains or 3 other protein supplements. J Dairy Sci. 2010;93(5):2095-2104.

    [CrossRef] [Google Scholar] [PubMed]

44. Dorea JR, Armentano LE. Effects of common dietary fatty acids on milk yield and concentrations of fat and fatty acids in dairy cattle. Anim Prod Sci. 2017;57(11):2224-2236.

    [CrossRef] [Google Scholar]

45. Lopes JC, Harper MT, Giallongo F, Oh J, Smith L, Ortega-Perez AM, et al. Effect of high-oleic-acid soybeans on production performance, milk fatty acid composition, and enteric methane emission in dairy cows. J Dairy Sci. 2017;100(2):1122-1135.

    [CrossRef] [Google Scholar] [PubMed]

46. He M, Armentano LE. Effect of fatty acid profile in vegetable oils and antioxidant supplementation on dairy cattle performance and milk fat depression. J Dairy Sci. 2011;94(5):2481-2491.

    [CrossRef] [Google Scholar] [PubMed]

47. He M, Perfield KL, Green HB, Armentano LE. Effect of dietary fat blend enriched in oleic or linoleic acid and monensin supplementation on dairy cattle performance, milk fatty acid profiles, and milk fat depression. J Dairy Sci. 2012;95(3):1447-1461.

    [CrossRef] [Google Scholar] [PubMed]

48. Stoffel CM, Crump PM, Armentano LE. Effect of dietary fatty acid supplements, varying in fatty acid composition, on milk fat secretion in dairy cattle fed diets supplemented to less than 3% total fatty acids. J Dairy Sci. 2015;98(1):431-442.

    [CrossRef] [Google Scholar] [PubMed]

49. Yoon BK, Jackman JA, Valle-González ER, Cho NJ. Antibacterial free fatty acids and monoglycerides: Biological activities, experimental testing, and therapeutic applications. Intern J Mol Sci. 2018;19(4):1114.

    [CrossRef] [Google Scholar] [PubMed]

50. Chelikani PK, Bell JA, Kennelly JJ. Effects of feeding or abomasal infusion of canola oil in Holstein cows 1. Nutrient digestion and milk composition. J Dairy Res. 2004;71(3):279-287.

    [CrossRef] [Google Scholar] [PubMed]

51. Prom CM, Lock AL. Replacing stearic acid with oleic acid in supplemental fat blends improves fatty acid digestibility of lactating dairy cows. J Dairy Sci. 2021; 104(9):9956-9966.

    [CrossRef] [Google Scholar] [PubMed]

52. Baldin M, Rico DE, Green MH, Harvatine KJ. An in vivo method to determine kinetics of unsaturated fatty acid bio hydrogenation in the rumen. J Dairy Sci. 2018; 101(5):4259-4267.

    [CrossRef] [Google Scholar] [PubMed]

53. de Souza J, Prom CM, Lock AL. Altering the ratio of dietary palmitic and oleic acids affects nutrient digestibility, metabolism, and energy balance during the immediate postpartum in dairy cows. J Dairy Sci. 2021; 104(3):2910-2923.

    [CrossRef] [Google Scholar] [PubMed]

54. Prom CM, dos Santos Neto JM, Lock AL. Abomasal infusion of different exogenous emulsifiers alters fatty acid digestibility and milk fat yield of lactating dairy cows. J Dairy Sci. 2022; 105(4):3102-3112.

    [CrossRef] [Google Scholar] [PubMed]

55. Prom CM, dos Santos Neto JM, Newbold JR, Lock AL. Abomasal infusion of oleic acid increases fatty acid digestibility and plasma insulin of lactating dairy cows. J Dairy Sci. 2021; 104(12):12616-12627.

    [CrossRef] [Google Scholar] [PubMed]

56. Spears JW. Trace mineral bioavailability in ruminants. J Nutr. 2003;133(5):1506S-1509S.

    [CrossRef] [Google Scholar] [PubMed]

57. Flachowsky G, Franke K, Meyer U, Leiterer M, Schöne F. Influencing factors on iodine content of cow milk. Euro J Nutr. 2014:351-365.

    [CrossRef] [Google Scholar] [PubMed]

58. Veselý A, Křížová L, Třináctý J, Hadrová S, Navrátilová M, Herzig I, et al. Changes in fatty acid profile and iodine content in milk as influenced by the inclusion of extruded rapeseed cake in the diet of dairy cows. Czech J Anim Sci. 2009: 201-209.

    [CrossRef] [Google Scholar]

59. Trøan G, Pihlava JM, Brandt-Kjelsen A, Salbu B, Prestløkken E. Heat-treated rapeseed expeller press cake with extremely low glucosinolate content reduce transfer of iodine to cow milk. Anim Feed Sci Technol. 2018; 239:66-73.

    [CrossRef] [Google Scholar]

60. Weiss WP, Wyatt DJ, Kleinschmit DH, Socha MT. Effect of including canola meal and supplemental iodine in diets of dairy cows on short-term changes in iodine concentrations in milk. J Dairy Sci. 2015;98(7):4841-4849.

    [CrossRef] [Google Scholar] [PubMed]

61. Erdman R, Iwaniuk M. DCAD: It's not just for dry cows. Proc Florida Nutr Conf.  2017.
62. Vuorela S, Meyer AS, Heinonen M. Impact of isolation method on the antioxidant activity of rapeseed meal phenolics. J Agric Food Chem. 2004;52(26):8202-8207.

    [CrossRef] [Google Scholar] [PubMed]

63. Wanasundara UN, Amarowicz R, Shahidi F. Partial characterization of natural antioxidants in canola meal. Food Res Intern. 1995;28(6):525-530.

    [CrossRef] [Google Scholar]

64. Loganes C, Ballali S, Minto C. Main properties of canola oil components: A descriptive review of current knowledge. Open Agri J. 2016.

    [CrossRef] [Google Scholar]

65. Huhtanen P, Hetta M, Swensson C. Evaluation of canola meal as a protein supplement for dairy cows: A review and a meta-analysis. Can J Anim Sci. 2011;91(4):529-543.

    [CrossRef] [Google Scholar]

66. Martineau R, Ouellet DR, Lapierre H. Feeding canola meal to dairy cows: A meta-analysis on lactational responses. J Dairy Sci. 2013; 96(3):1701-1714.

    [CrossRef] [Google Scholar] [PubMed]

67. Martineau R, Ouellet DR, Lapierre H. The effect of feeding canola meal on concentrations of plasma amino acids. J Dairy Sci. 2014 ;97(3):1603-1610.

    [CrossRef] [Google Scholar] [PubMed]

68. Moura DC, Alessi KC, Assis JR, Torres, RN, Soares SR, Donadia AB, et al. Meta-analysis of the use of canola meal in diets for dairy cows. J Dairy Sci.2018,100 (Suppl 2): 107.

    [CrossRef] [Google Scholar] [PubMed]

69. Martineau R, Ouellet DR, Lapierre H. Does blending canola meal with other protein sources improve production responses in lactating dairy cows? A multilevel mixed-effects meta-analysis. J Dairy Sci. 2019;102(6):5066-5078.

    [CrossRef] [Google Scholar] [PubMed]

70. Broderick GA Faciola AP, Nernberg L, Hickling D. Effect of replacing dietary soybean meal with canola meal on production of lactating dairy cows. J Dairy Sci.2012;95( Suppl 2): 249.
71. Broderick GA, Faciola AP, Armentano LE. Replacing dietary soybean meal with canola meal improves production and efficiency of lactating dairy cows. J Dairy Sci. 2015; 98(8):5672-5687.

    [CrossRef] [Google Scholar] [PubMed]

72. Galindo CE, Ouellet DR, Maxin G, Martneau R, Pellerin D, Lapierre H. Effects of protein and forage sources on milk production, rumen parameters and intestinal digestibility in lactating dairy cows. J Dairy Sci. 2017;100:111.

    [CrossRef] [Google Scholar]

73. Gidlund H, Hetta M, Krizsan SJ, Lemosquet S, Huhtanen P. Effects of soybean meal or canola meal on milk production and methane emissions in lactating dairy cows fed grass silage-based diets. J Dairy Sci. 2015; 98(11):8093-8106.

    [CrossRef] [Google Scholar] [PubMed]

74. Holtshausen L, Benchaar C, Kröbel R, Beauchemin KA. Canola meal vs soybean meal as protein supplements in the diets of lactating dairy cows affects the greenhouse gas intensity of milk. Animals. 2021;11(6):1636.

    [CrossRef] [Google Scholar] [PubMed]

75. Kuehnl J, Kalscheur K. Production effects of feeding soybean meal versus canola meal to dairy cows with low versus high residual feed intake. J Dairy Sci. 2022.

    [Google Scholar]

76. Paula EM, Broderick GA, Danes MA, Lobos NE, Zanton GI, Faciola AP. Effects of replacing soybean meal with canola meal or treated canola meal on ruminal digestion, omasal nutrient flow, and performance in lactating dairy cows.  J Dairy Sci. 2018; 101(1):328-339.

    [CrossRef] [Google Scholar] [PubMed]

77. Paula EM, Broderick GA, Faciola AP. Effects of replacing soybean meal with canola meal for lactating dairy cows fed 3 different ratios of alfalfa to corn silage. J Dairy Sci. 2020;103(2):1463-1471.

    [CrossRef] [Google Scholar] [PubMed]

78. Sánchez-Duarte JI, Kalscheur KF, Casper DP, García AD. Performance of dairy cows fed diets formulated at 2 starch concentrations with either canola meal or soybean meal as the protein supplement. J Dairy Sci. 2019; 102(9):7970-7979.

    [CrossRef] [Google Scholar] [PubMed]

79. Brito AF, Broderick GA. Effects of different protein supplements on milk production and nutrient utilization in lactating dairy cows. J Dairy Sci. 2007; 90(4):1816-1827.

    [CrossRef] [Google Scholar] [PubMed]

80. Maesoomi SM, Ghorbani GR, Alikhani M, Nikkhah A. Canola meal as a substitute for cottonseed meal in diet of midlactation Holsteins. J Dairy Sci. 2006 ;89(5):1673-1677.

    [CrossRef] [Google Scholar] [PubMed]

81. Acharya IP, Schingoethe DJ, Kalscheur KF, Casper DP. Response of lactating dairy cows to dietary protein from canola meal or distillers’ grains on dry matter intake, milk production, milk composition, and amino acid status. Can J Anim Sci. 2015; 95(2):267-279.

    [CrossRef] [Google Scholar]

82. Mulrooney CN, Schingoethe DJ, Kalscheur KF, Hippen AR. Canola meal replacing distillers grains with solubles for lactating dairy cows. J Dairy Sci. 2009; 92(11):5669-5676.

    [CrossRef] [Google Scholar] [PubMed]

83. Abeysekara S, Mutsvangwa T. Effects of feeding canola meal or wheat dried distillers' grains with solubles alone or in combination as the major protein sources on ruminal function and production in dairy cows. J Dairy Sci. 2016.

    [CrossRef] [Google Scholar]

84. Chibisa GE, Christensen DA, Mutsvangwa T. Effects of replacing canola meal as the major protein source with wheat dried distillers grains with solubles on ruminal function, microbial protein synthesis, omasal flow, and milk production in cows J Dairy Sci. 2012; 95(2):824-841.

    [CrossRef] [Google Scholar] [PubMed]

85. Mutsvangwa T, Kiran D, Abeysekara S. Effects of feeding canola meal or wheat dried distillers grains with solubles as a major protein source in low-or high-crude protein diets on ruminal fermentation, omasal flow, and production in cows. J Dairy Sci. 2016;99(2):1216-1227.

    [CrossRef] [Google Scholar] [PubMed]

86. Beauchemin KA, McGinn SM, Benchaar C, Holtshausen L. Crushed sunflower, flax, or canola seeds in lactating dairy cow diets: Effects on methane production, rumen fermentation, and milk production. J Dairy Sci. 2009; 92(5):2118-2127.

    [CrossRef] [Google Scholar] [PubMed]

87. Vincent IC, Hill R, Campling RC. A note on the use of rapeseed, sunflower and soyabean meals as protein sources in compound foods for milking cattle. Anim Sci. 1990; 50(3):541-543.

    [CrossRef] [Google Scholar]

88. Moate PJ, Williams SR, Grainger C, Hannah MC, Ponnampalam EN, Eckard RJ. Influence of cold-pressed canola, brewers grains and hominy meal as dietary supplements suitable for reducing enteric methane emissions from lactating dairy cows. Anim Feed Sci Technol. 2011.

    [CrossRef] [Google Scholar]

89. Hristov AN, Domitrovich C, Wachter A, Cassidy T, Lee C, Shingfield KJ, et al. Effect of replacing solvent-extracted canola meal with high-oil traditional canola, high-oleic acid canola, or high-erucic acid rapeseed meals on rumen fermentation, digestibility, milk production, and milk fatty acid composition in lactating dairy cows. J Dairy Sci. 2011; 94(8):4057-4074.

    [CrossRef] [Google Scholar] [PubMed]

90. Reynolds MA, Brown-Brandl TM, Judy JV, Herrick KJ, Hales KE, Watson AK, et al. Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming common coproducts. J Dairy Sci. 2019; 102(1):320-333.

    [CrossRef] [Google Scholar] [PubMed]

91. Kobayashi Y. Abatement of methane production from ruminants: Trends in the manipulation of rumen fermentation. Asian-Aust J Anim Sci. 2010; 23(3):410-416.

    [CrossRef] [Google Scholar]

92. Beauchemin KA, Kreuzer M, O’mara F, McAllister TA. Nutritional management for enteric methane abatement: A review. Aust J Exp Agri. 2008; 48(2):21-27.

    [CrossRef] [Google Scholar]

93. Gidlund H, Hetta M, Huhtanen P. Milk production and methane emissions from dairy cows fed a low or high proportion of red clover silage and an incremental level of rapeseed expeller. Livestock Sci. 2017; 197:73-81.

    [CrossRef] [Google Scholar]

94. Moore SA, Kalscheur KF, Aguerre MJ, Powell MJ. Effects of canola meal and soybean meal as protein sources on methane and ammonia emissions of high producing dairy cows. J Anim Sci. 2016.

    [CrossRef] [Google Scholar]

95. Ramirez-Bribiesca JE, McAllister T, Ungerfeld E, Ortega-Cerrilla ME. In vitro rumen fermentation and effect of protein fractions of canola meals on methane production. Sci Agr. 2018.

    [CrossRef] [Google Scholar]

96. Williams SR, Hannah MC, Eckard RJ, Wales WJ, Moate PJ. Supplementing the diet of dairy cows with fat or tannin reduces methane yield, and additively when fed in combination. Ani. 2020; 14(S3):464-472.

    [CrossRef] [Google Scholar] [PubMed]

97. Hassanat F, Gislon G, Beauchemin KA, Benchaar C. Canola meal in dairy cow diets: Effect on nitrogen utilization. J Dairy Sci. 2020. 

    [Google Scholar]