Plants developed highly sophisticated mechanisms to cope with stressors, many of which are based on bioactive substances that can be extracted from plant material. One way of empowering animals to cope with stressors better is therefore to supplement their diets with relevant plant extracts and bioactive substances derived from plants.
Stress reactions to mycotoxins in animals
Many trials have proven the significant negative impact of mycotoxins on performance in pigs and poultry. Looking at the effects of mycotoxins at a cellular level, it is becoming obvious that many reactions seen to mycotoxins in animals are those commonly seen in response to other stressors.
One reaction to stressors is an increase in Reactive Oxygen Species (ROS). ROS are produced endogenously by normal metabolic processes, but amounts may be increased markedly by certain stressors, including mycotoxins. Deficiencies of natural protective substances or excess exposure to stimulators of ROS production may result in oxidative stress, which occurs when ROS exceed the capacity of antioxidants. Oxidative stress is a major factor related to the development of inflammatory diseases.
Consumption of DON-contaminated feed in pigs, not only increases oxidative stress, it has also shown to impact the gastrointestinal tract, causing epithelial injuries of the stomach and the intestine, leading to intestinal inflammatory response. In vitro and in vivo studies have also demonstrated that DON compromises the intestinal barrier function and increases gut permeability. Furthermore, it has been shown that mycotoxins modify the intestinal microbiota in pigs and in poultry. However, not all mycotoxins show this effect. For example, feeding pigs with fumonisin was not reported to induce any modification of the intestinal microbiota, whereas DON did. In the chicken a high dose of ochratoxin exhibited significant numbers of Salmonella typhimurium in the digestive tract when compared to non-administered birds. However, feeding birds with high levels of aflatoxin or T-2 toxin had no effect on incidence or severity of S. typhimurium colonization.
Taken all together these type of responses at the cellular level will predispose the animal to intestinal and systemic infections and impair efficient digestion and absorption of nutrients, with the associated effect on animal productivity and efficiency.
How plants adapt to stress factors
Plants are stressed by environmental changes that threaten their health, such as drought, pathogens and plant-eating insects. However, compared to animals and humans, plants have to be a lot more sophisticated with their response to stress since they are stuck where they grow and cannot run from the stress they are exposed to.
The exposure of plants to unfavorable environmental conditions increases the production of reactive oxygen species (ROS) and the ROS detoxification process in plants is essential for the protection of plant cells against the toxic effect of ROS. The ROS detoxification systems in plants include enzymatic and non-enzymatic antioxidant. Non-enzymatic antioxidants involved include phenolic compounds, flavonoids, alkaloids, tocopherol and carotenoids. The antioxidant defense systems work in concert to control the cascades of uncontrolled oxidation and protect plant cells from oxidative damage.
Apart from antioxidants, plants contain a multitude of bioactive substances, with a variety of proven properties such as anti-inflammatory, anti-microbial and aromatic, which are part of their mechanisms for survival and defense. The combination of the many substances makes plants polyvalent to different stressors and threats to survival and hence more agile.
Beat mycotoxins to the punch with plant extracts
As mentioned above mycotoxins can lead to a variety of stress reactions at the cellular level, which again will affect the animal’s performance, efficiency and susceptibility to disease.
Through a multitude of bioactive substances, with a variety of adaptive properties plants are very well equipped to be polyva¬lent to different stressors and to prevent their negative impact. Bioactive substances derived from plants have also shown to support humans and animals to adapt to stressors more ade¬quately and help counteract some of the negative physiological and metabolic side effects.
Since the stress reactions seen to mycotoxins are very similar to those commonly seen in response to other stressors, applying the right combination of plant extracts to animal feed can therefore help the animal become more robust and efficient in the face of mycotoxin challenges.