Weaning is a critical time for piglets. They change environment, they are separated from the sow and are frequently mixed with piglets from other origins. More importantly, they change diets, transitioning from the sow milk (lactose-based diet, easily digestible) to a dry pelleted starter feed (plant-based diet, often less digestible).
This change of diet and the various stressors associated to weaning often leads to a drop in feed intake post-weaning, followed by a reduction of growth, and intestinal dysbiosis. The extent of this growth reduction and intestinal dysbiosis depends on how rapidly the pig is able to adapt to its new situation.
Several studies demonstrate a reduction of villus height the days following weaning. It takes at least 7 days to recover the height from before weaning. This reflects the impairment of the intestinal barrier and is correlated to an increase in intestinal permeability. As feed antigens cross the intestinal epithelium from the lumen to the blood flow, they are recognised by the innate immune system as ‘potential aggressors’. Therefore, an inflammatory response can be elicited, which, not controlled, can lead to post-weaning diarrhea (Figure 1).
Therefore, it seems critical to limit the drop of feed intake at weaning to avoid a chain reaction leading to growth reduction and intestinal dysbiosis leading to post-weaning diarrhea and pain.
How to limit the drop in feed intake and the growth reduction at weaning
Several actions can be taken to limit the feed intake drop at weaning:
- Wean older and more mature piglets
- Offer liquid or solid creep feed during lactation
- Feed formulation and technology
- Use feed additives
Some of these actions depend on the production system: weaning older piglets is not always possible without changing the farm schedule and conflicting with sow health and longevity. Other actions do not show consistent results: creep feeding highly depends on whether the piglet consumed creep feed or not during the pre-weaning period. Feed formulation (e.g., using more digestible source of proteins), feed technology (e.g., pellets vs. flour diets), and the use of feed additives can be used to make the feed more palatable and attractant for young pigs.
The use of specific molecules to control inflammation and oxidative stress
The set of inflammation is part of the innate response of the immune system. It is necessary to fight exogenous pathogens. However, if not controlled, it can become detrimental for the organism and damage tissues. As shown in the figure above, inflammation can also cause fever. The pig is down and does not eat, which fuels this vicious circle once again, leading to growth reduction.
Several plant extracts such as essential oils and spices have been proven to limit inflammation and the oxidative stress when fed to piglets post-weaning. Their use could contribute to the return to homeostasis after weaning by securing intestinal function and integrity. However, piglets are very sensitive to these ingredients and care must be taken when formulating these products to make them palatable enough for young animals. At Phodé, we design our products using specific galenic to protect these active ingredients and to match piglets’ taste!
The use of sensory molecules to stimulate the appetite at weaning
As the specialist in olfactory and bio-innovative solutions destined to animal feed, Phodé has developed a new solution that attracts piglets to feed via volatile molecules, creates a pleasure sensation and positive memorization of the feed, and stimulates the appetite in the pituitary by activating the hypothalamic-pituitary-adrenal (HPA) axis.
A study led in France demonstrated an increase in the time spent by the piglets at the feeder when feed was supplemented with this solution for two weeks post-weaning (Figure 2). The average daily feed intake of the piglets also increased by 4.2% during the supplementation period.
To go further, this solution could also be of interest in the creep feed. After weaning, the pigs would then identify the smell as ‘familiar’, thereby reducing the feed neophobia even more quickly.
Securing the feed intake at weaning: a multifactorial approach
To conclude, managing the transition at weaning depends on several actions that can be implemented from the early life of the piglets. The use of selected sensory solutions in the diet can help to limit the feed neophobia and increase the intake of pigs at weaning. Therefore, these approaches along with good farm practices are key to secure piglets’ growth at weaning, improve their well-being.
