21 September 2022 – When talking about mycotoxins and strategies to mitigate their impact on animal health and performance, conversations often centre around monogastrics, and mostly poultry. What tends to dominate these conversations a little less is how these compounds can impact ruminants, and dairy cows in particular.
One reason for that might be because ruminants can neutralise some mycotoxins on their own. But this ability does not necessarily mean that they are completely spared the impacts on their performance. According to Arno Duchateau, Global Product Manager at Impextraco, this system is not perfect and does not necessarily prevent these animals from developing mycotoxicosis.
So, in the below Industry Perspectives chat, he shares with Feedinfo why it is vital for dairy farmers to have a mycotoxins mitigation strategy in place, what an effective strategy for dairy cows should look like, and why Impextraco’s mycotoxin eliminator, Elitox, should form a vital part of it. He also takes us through key findings of Elitox investigations, showing the product’s efficacy in combatting mycotoxin carryover into milk and reduction of mastitis.
[Feedinfo] Ruminants are less susceptible to mycotoxins than monogastrics. So why should ruminant farmers be concerned about them at all?
[Arno Duchateau] Ruminants are more robust animals in comparison to poultry and swine. This is also true and accepted for the effects of individual mycotoxins. This can be accounted for by the presence of the rumen. This fermentation vessel has a large population of microbes that are able to degrade mycotoxins. Hereby the original ingested mycotoxin will be transformed to another, potentially less toxic metabolite.
However, the total mixed ration that ruminants are fed is a very complex diet of concentrates and forages. Consequently, ruminants come into contact with a wider variety of mycotoxins than monogastrics.
Moreover, not all mycotoxins are transformed in the rumen to less toxic metabolites. Aflatoxin, for example, is only partly converted and zearalenone is converted to another toxic metabolite. In fact, some mycotoxins have direct effects on the microbial population in the rumen, resulting in less efficient fermentation and mycotoxin degradation. In total, there will be a synergistic load of mycotoxins and metabolites that is of concern for the animal’s health and the farmer’s income. We should also not forget human health as aflatoxins are known to be excreted in the milk.
[Feedinfo] Let’s first look at dairy farmers and the potential financial impact on their operations should they have no mycotoxin strategy in place.
[Arno Duchateau] There are multiple aspects to consider when talking about the impact of mycotoxicosis on the turnover of dairy farmers. Firstly, milk production will be reduced, which directly affects income. Secondly, milk quality will be impaired. This is due to the elevated somatic cell count as a consequence of inflammation during mycotoxicosis. This could translate into the possible rejection of milk quality premiums due to quality standards not being fulfilled. Last, but not least, mastitis is a disease which is associated with mycotoxicosis, whose veterinary treatments represent an extra cost for the farmer.
[Feedinfo] So, what does an effective dairy mycotoxin strategy look like? What are some of the key factors that should be considered when developing one?
[Arno Duchateau] While mycotoxin prediction and detection are necessary tools in order to have a glimpse on the mycotoxin load, uncertainty remains about the true load that is present in the final feed. This is especially the case with the total mixed ration, where many feedstuffs are mixed together before feeding. Therefore, mycotoxin mitigation should also form part of this strategy and be able to tackle a broad spectrum of mycotoxins. Although each mycotoxin will exert a specific damage (zearalenone, for example, targets the reproductive system) their subclinical effects on the immune system and gut integrity overlap. Therefore, mycotoxicosis can be prevented when these common primordial effects are counteracted by mycotoxin solutions.
[Feedinfo] Let’s zoom in on Elitox, your mycotoxin eliminator that you are putting forward as a solution. Considering the more intricate digestion and varied diet of the dairy cow, how does it go about negating the effects of various mycotoxins in ruminants?
[Arno Duchateau] Elitox is active in the gut. In the lumen, it will absorb mycotoxins and wash them out. Additionally, Elitox provides the necessary ingredients to protect vital tissues like the intestinal epithelium and internal organs from mycotoxin stress. Moreover, mycotoxins have a direct effect on the immune system by both lowering the number of immune cells and by triggering an inflammation pathway. Elitox balances the immune status and avoids inflammation. Lastly, Elitox facilitates a reduction in secondary diseases that manifest when the animal has mycotoxin-related stress.
[Feedinfo] So, what can you share with us on the product’s efficacy against some of the adverse effects of mycotoxicosis in dairy cattle, especially on feed intake, feed efficiency, and milk yield?
[Arno Duchateau] Dairy cows lower feed intake when they receive contaminated feed. Moreover, mycotoxins have an effect on the rumen population. As a consequence, feed efficiency is reduced as rumen fermentation is affected and less nutrients can be digested and absorbed. When feed efficiency is lowered, milk yield will decrease. Simultaneously, mycotoxins will cause inflammation and therefore the somatic cell count of the milk increases, which, in turn, negatively impacts milk yield. Furthermore, when the animal’s health status decreases, its productivity will be impaired.
In a field trial, we observed that Elitox improved the average feed intake. Overall, the customer noticed an improvement of both the health status and the condition of the herd. In another trial, we observed that Elitox lowered average somatic cell count of a dairy herd by 20% over a 5-month period.
[Feedinfo] What about mycotoxin carryover to milk? As you mentioned earlier, when aflatoxins are fed to dairy cows, they can show up in the milk produced. How can Elitox be of help here and how effective can it be at preventing carryover? What findings can you share with us?
[Arno Duchateau] Animals have an internal metabolism to cope with toxins. They can transform, degrade, accumulate and excrete toxins. Specifically, aflatoxin B1 is transformed into aflatoxin M1 and excreted in the milk. Despite, the conversion, this metabolite is still harmful for both calves and humans, so the carryover effect from animals to humans is one of the biggest concerns related to mycotoxins. Consequently, the EU limit for aflatoxin B1 in the final feed for dairy cows is set at a very low level of 5 ppb.
Aflatoxins are planar polar molecules, so can be adsorbed by binding agents. We examined this carryover effect in dairy cows. The Elitox group showed an aflatoxin M1 level in the milk, which was significantly lower than the group receiving the same feed, but without Elitox.
[Feedinfo] You also mentioned mastitis being a disease which is associated with mycotoxicosis. What is the connection between the two? You’ve also investigated how Elitox can be of help in this regard. What are the key findings that you can share with us?
[Arno Duchateau] Mastitis is an inflammation of the mammary gland mainly caused by a bacterial infection. Globally, it is the costliest disease for the dairy industry as it directly impacts milk quality. Due to the inflammation, immune cells are sent to the udder and leak into the milk. This increases the somatic cell count and milk quality is reduced. Mycotoxicosis is a predisposing factor for this disease as it lowers the immunity and triggers inflammation. As a consequence, the animal is more prone to secondary diseases, like mastitis.
Although Elitox has no direct effect against the mastitis-causing bacteria, the incidence of mastitis in a dairy herd can be reduced by eliminating the stress of mycotoxins and by avoiding inflammation. Again, this was observed in a field trial, where Elitox was able to reduce the number of treated cows by 20%. This result was consistent with the reduction in somatic cell count.
Published in association with Impextraco