It is well known that the immediate consequence of weaning is a drastic reduction in feed intake and a loss of body weight in the first few days. Some piglets will not even eat during the first 48 hours. This lack of nutrient intake has a dramatic impact on the anatomy, functions and microorganisms of the gastrointestinal tract, impairing efficient digestive processes and barrier functions. Many researchers have shown that this reduced nutrient intake leads to villi atrophy (decrease of villus height up to 30%), negative effects on tight junctions and lower barrier function of the gastrointestinal tract (GIT).
After this reduced feed intake, piglets start to eat and will often try to compensate these nutrient deficiencies, and end up overeating. Excess feed intake at a time of lower digestibility means that protein will be less digested, providing a good source of nutrients for pathogens such as E. coli. During this period, pathogens are also better able to adhere to the intestine wall where they can multiply and produce endotoxins.
Endotoxins, or lipopolysaccarides (LPS), are parts of the cell wall of Gram-negative bacteria (e.g. E. coli, Salmonella), that are released by bacteria after death or during proliferation. GIT barrier impairment through decreased nutrient intake or overconsumption, for example, can lead to an increased passage of endotoxins, which in turn result in local or systemic damage or inflammatory reactions. Endotoxins themselves are able to damage tight junctions among epithelial layer cells, enhancing the already compromised TEER (Trans Epithelial electric Resistance) by the presence of mycotoxins, or the reverse. TEER is a measure of gut wall permeability, giving account of the level of leaking situation that brings a dramatic increase of pathological consequences by the adsorption and flow to the blood of endogenous and exogenous toxins such as bacteria. Endotoxins are synergetic with tricothecenes in the leaking effect. Not to be underestimated, the effect of endotoxins on feed intake can reach a 26% decrease—a considerable amount.
Nutritional strategies to reduce the stress around weaning and to help to overcome the weaning dip are often advised in the direction of increasing nutrient intake and implementing highly digestible ingredients. In recent research increasingly demonstrates that even small amounts of the mycotoxin deoxynivalenol (DON) affects the intestinal immune system and harms intestinal villi. A healthy gastrointestinal tract is crucial for an efficient uptake of nutrients, immune system function, and the indigenous microflora.
Accept the reality
In recent experiment with DanAVL genetics, the main goal of the trial was to see the effect of Mycofix® on the technical performance, diarrhea score and ear necrosis in a non-contaminated feed. This setup should prove the efficiency of Mycofix® on the reduction of negative effects of endotoxins in this period. After analyzing of the different badges of the trial feed there was shown a medium-low contamination level of DON in the weaner diet (between 600-800 ppb, Figure 1). The feed producer was unaware of this low contamination in the ingredients.
Figure 1. Mycotoxin contamination in feed (ppb).
The trial was conducted with 720 piglets. Those in the Mycofix®-supplemented treatment group gained 0.6 kg more (Figure 2) and had an improved feed conversion rate 0.12 (Figure 3).
Figure 2. Body weight (kg/animal). Figure 3. FCR (kg/kg).
In addition to performance, some animal health-related parameters that may occur in connection with enhanced mycotoxins in the feed or increased levels of endotoxins in the GIT were evaluated as well. Mycofix® showed a lower incidence of diarrhea in the first 14 days after weaning (Figure 4), and of top ear necrosis (Figure 5). This trial offers a perfect example how problems in the field could be diagnosed. In discussion about disappointing results of performance of piglets, often the quality of the ingredients assumed to be correct. It can be difficult to accept that even low level mycotoxin contamination can have huge influences on performance and health status. Another point of view in this context could be that the effect of adding Mycofix® has influence on the reduction of the negative effect of endotoxins. Besides formulating pre-starter / weaning diets on increased nutrient intake, more highly digestible ingredients and digestion-enhancing additives, it is also recommended to use Mycofix® in a standard solution to counteract low level mycotoxin contamination and the negative effects of endotoxins on piglets’ heath and performance.
Figure 4. Diarrhea score (1 = no diarrhea to 5 = severe diarrhea).
Figure 5. Score top ear necrosis (1 = no necrosis to 5 = severe necrosis).