Successful weaning starts with healthy gut development

Neonatal piglets face many challenges as they do not get sufficient prenatal maternal immunity and have a limited energy supply in the body. To overcome this hiccup, Mother Nature provides the new-born piglet with a high permeable epithelium enabling macromolecular passage of immunoglobulins and vitamins. The effective gut closure normally happens within 24hrs after birth and is modulated by the colostrum supplied by the sow. The colostrum has several functions such as maturing and modulating the intestinal tract and its microbiome by specific prebiotic compounds and other bioactive substances. After gut closure the important function of absorbing nutrients and keeping out pathogens can start. The gut barrier development however not only includes the epithelial barrier, transport functions and immune system maturation, but it also involves the development and the functioning of the enteric nervous system (ENS). The ENS undergoes several important developmental changes in early life including the synthesis of neurochemicals and synapse formation. It functions separately from the central nervous system however Moeser et al., indicated that the association between the ENS and the higher centres also plays a key role in animal well-being, health, structure and function of the GIT.

Neonatal gut development

The window of opportunity to develop the gut barrier function lasts for several weeks after weaning and coincides with the normal weaning age in nature. However, modern weaning happens much earlier and compromises this development. In addition to this, weaning piglets are stressed around this phase: change from milk to solid feed, new littermates, new environment are to name a few. These stressors play an important role in the gut barrier functioning. Stress contributes to higher permeability of the epithelium and leads to the so called ‘leaky gut’. Translocation of pathogens consequently can cause intestinal disorders and the need for medical intervention. The leaky gut syndrome is a very important contributor to post weaning diarrhoea and it takes several weeks before a compromised gut barrier is restored in its original function. However, by applying appropriate early life interventions we can steer neonatal gut development, reduce the risk of pathogen translocation and overcome gastro-intestinal disorders such as post-weaning diarrhoea without the use of therapeutic ZnO and with no or very limited antibiotic use.

Farrowing house interventions

Successful weaning starts prenatal by proper sow feeding to ensure a smooth farrowing process and giving birth to vital piglets. These piglets will locate the udder more rapidly allowing them to take in colostrum sooner and in higher quantity. In addition, last-born piglets, often less vital piglets, are condemned to the rear teats producing less colostrum and milk. Management strategies such as split suckling can help the intake of colostrum by the smaller, more vulnerable piglets. Colostrum plays an important role in the gut closure process, protecting the piglet from pathogen translocation. Besides good colostrum management, training the piglet to eat solid feed is an excellent way of preparing it for weaning. Middelkoop et al., indicated that getting used to solid feed in a playful way will ‘train the brain’. The author described it as: “training for the unexpected hypothesis”, in other words getting the piglets used to new situations at an early phase and therefore reducing stress occurrence later in life. The authors did not see a higher feed intake before weaning, but after weaning piglets ate more and especially earlier, which is important to maintain the villi structure created before weaning.

Creep feeding

An early creep feed such as Babito is especially developed to train the piglets to eat and stimulate their exploratory behaviour as the product sticks to the nose of the piglet and contains specific corn flakes allowing the piglets to discover the feed in a playful way. Due to its specific composition it will also develop the gut structure (eg. villi formation) and stimulate enzyme secretion to digest plant based raw materials. This will make the transition to a weaning diet smoother and reduce stress. Recently Babito has been enriched with the new START+ concept. This concept contains specific components mimicking the prebiotic oligosaccharides present in the colostrum. Research in collaboration with universities showed that START+ has a positive effect on gut microbiome, gut structure and gut barrier function (Figure 1).

Figure 1 – Gut barrier function. measured as TEER (TransEpithelial Electrical Resistance) after 4 hours on a Caco2 cell line with or without stressor. (Relative value compared to T0h = 100%)

Multifactorial approach to weaning

At weaning, it is of utmost importance to maintain the created gut structure, the commensal microbiome and a low epithelial permeability. This demands a multifactorial approach focusing on management and nutrition around weaning. Within the nutritional approach, the Aim For Zero programme was developed: adapted formulation and targeted functional feed ingredients to keep the gut healthy to reduce the dependency of ZnO and antibiotics. From a nutritional point of view, it focusses on applying optimal post weaning formulation, aiming to avoid protein fermentation and steering carbohydrate fermentation. This approach needs to be adapted according to the different genetics as this has an important effect on the formulation strategy to follow. The functional feed ingredient concept is aiming at reducing pathogens, disarming endotoxins and maintaining gut barrier integrity. The latter is being accomplished by specific polyphenols with a strong focus on gut integrity (Figure 2). The combination of START+ around weaning with the Aim for Zero concept after weaning has proven in practice to be very beneficial to piglet health and growth.

Figure 2 – Influence of oxidative stress and natural anti-oxidants on the intestinal permeability.

Healthy weaning process

Gut barrier development in neonatal piglets is a complex process and needs to be done in a very short period of time. Weaning stress should be avoided as much as possible as it jeopardises the gut structure. In addition, effective gut integrity improving interventions and a well-balanced formulation will help to prevent a leaky gut and will be a prerequisite for a healthy weaning process.