Essential, long chain polyunsaturated (omega-3 and omega-6) fatty acids and rumen protected (bypass) protein sources play an important role in the nutrition of high producing dairy cows. These nutrients are indispensable for reaching appropriate levels of production and also play an important role in maintaining an optimal health status and increasing productive life. Linolex can provide a solution to these challenges. This linseed-based product has a significant undegradable dietary protein content of minimum 60% that can contribute to fulfilling the increased protein and amino acid requirements of high yield dairy cows, while it’s alpha-linolenic acid content has a beneficial effect on the reproductive performance of dairy cows.
One of the greatest challenges in modern dairy cow nutrition is to improve the reproductive parameters of high producing cows. Linseed is a raw material that has the potential to alleviate this problem because a significant part of its oil content (55%) is essential, polyunsaturated omega-3 fatty acids. It is important to note that the animal is not capable of producing omega-3 fatty acids, so appropriate fatty acid supplementation is essential for dairy cows. Alpha-linolenic acid (ALA; C18:3, n-3) is an important omega-3 fatty acid and is the precursor of eicosapentaenoic acid (C20:5-EPA) and docosahexaenoic acid (C22:6-DHA) produced in the body. EPA and DHA play key roles in the reproductive process (Moallem, 2018). It is also worth noting that supplementing the ration with appropriate fatty acids decreases the energy deficit at the beginning of lactation, which also contributes to improving reproductive performance on the long-term.
Genetic improvement has led to an increase in protein requirements for high yielding dairy cows. Microbial proteins produced in the rumen alone are not enough to fully meet this requirement. And since microbial proteins provide only 50-60% of the protein requirement, the remaining part has to be supplemented by dietary bypass protein.
It has to be pointed out that the UDP content of linseed based products can be increased by appropriate chemical, physical treatments or a combination of them (Ganai et al., 2019), which allows them to play an important role in providing a sufficient protein supply to dairy cows. Instead of expensive chemical or combined solutions we use a cost-effective physical method, a thermomechanical treatment during the production process of Linolex. This gentle and continuously improved process makes Linolex a source of bypass protein and lipid that, according to our test results, has a UDP content of over 60% (relative to crude protein) and contributes to an optimal protein supply of dairy cows.
We tested the rumen degradability of Linolex’s nutrients in cooperation with the Hungarian University of Agriculture and Life Sciences. To test the rumen degradability of the crude protein content of the by-pass product produced by a thermomechanical process, we used two rumen fistulated Holstein cows. We performed the tests to evaluate the effect of the method used to achieve the bypass feature of the product on the rumen degradability of the crude protein and the UDP content of Linolex. For the purpose of the study we used the in sacco method (Mehrez és Ørskov, 1977; Ørskov és McDonald, 1979). For the control sample we used the mixed mash before heat treatment taken from the production line after going through the crusher and the disc mill. For the experimental sample we used the same mixture after it had undergone thermomechanical treatment.
For both samples (control and Linolex) we determined two incubation time points (0 and 16 hours). Measurements were taken at all incubation time points for both animals, with five replicates. Samples from time point “0” were not placed into the rumen but received the same treatment (washing, drying, chemical analysis) as the samples that were taken out of the rumen following incubation.
Chemical analysis revealed that the nutrient content of the feed samples were the same as measured by Bonfarm-Bábolna Takarmány Ltd. at their accredited laboratory, i.e. confirmed the values stated on the product sheet of Linolex (Table 1).
The graph in Figure 1 indicates that during it’s 16 hour stay in the rumen, the degradation of the protein content of Linolex was 14.20% lower in absolute terms than the control. Thermomechanical treatment causes a change in the structure of proteins and results in the Maillard reaction in the product. As a result, the RDP (Rumen Degradable Protein %) content of Linolex is reduced. During the Maillard reaction, reducing sugars react with free amino groups – under appropriate conditions – and are subject to multiple changes through a series of complex reactions. This results in the production of various aromatic components and brown pigments (melanoidins) (Csapó and Csapóné, 2003).
Under real life feeding conditions we can consider an outflow of 8% based on the Hungarian protein evaluation system for high yield dairy cows kept in intensive management systems. This means that we assume 8% of the rumen content leaves the rumen every hour. A 2% outflow rate is considered to be the maintenance level, 5% represents a moderate nutritional level. Results indicated in Figure 2 demonstrate that both the rapidly and the slowly degradable fractions of the crude protein content are reduced in Linolex.
The effect is significant, since the treatment resulted in a degradation of 36.07% of the proteins in Linolex in the rumen, while 50.14% was degraded in the control sample (Figure 2). In absolute terms this means that when feeding 1 kg of the control sample, 117.67 g of its protein content goes through the rumen without undergoing microbial degradation, while 150.87 g of protein from 1 kg Linolex will leave the rumen undegraded, which is an increase of 28.11%. This means that Linolex has a UDP content of almost 64%, while the control is about 10% lower.
In conclusion, the most important results are the following: both the rapidly and the slowly degradable fractions of the rumen degradable crude protein content of Linolex is reduced compared to the control samples, and the rumen bypass protein (UDP) content of Linolex was close to 64% after 16 hours of incubation. This value is 14% higher than for the control feed (which was about 50%). These results indicate that it is possible to increase the proportion of the bypass protein content in dairy cow rations with Linolex in a way that is also safe regarding blood urea nitrogen levels.
In summary we can say that it is recommended to use Linolex, the linseed based product of Bonafarm-Bábolna Takarmány Ltd. in the nutrition of dairy cows because of its favourable omega-3 fatty acid composition and high UDP ratio.
Literature:
- Csapó, J. – Csapóné Kiss, Zs. (2003): Élelmiszer-kémia. Mezőgazda Kiadó. Budapest. ISBN: 9789632866420.
- Ganai, A.M., Haq, Z., Beigh, Y.A., Sheikh, G.G. (2019): Bypass nutrient technology with recent advances for enhancing animal production: A review. Journal of Pharmacognosy and Phytochemistry. SP5: 269-275
- Mehrez, A.Z., Ørskov, E.R. (1977): A study of the artificial fibre bag technique for determining the digestibility of feeds in the rumen. Journal of Agriculture Science. 88, 645-650.
- Ørskov, E.R., McDonald, I. (1979): The estimation of protein degradability in the rumen from incubation measurements weighed according to rate of passage. Journal of Agriculture Science. 92:499–503.
- Moallem (2018): Invited review: Roles of dietary n-3 fatty acids in performance, milk fat composition, and reproductive and immune systems in dairy cattle. Journal of Dairy Science. 101(10), 8641-8661. https://doi.org/10.3168/jds.2018-14772.
Fédra Borbély
junior product manager
Zoltán Hatvani
“Iránytű” program trainee
Bonafarm-Bábolna Takarmány Ltd.
