Time to read: 10 min

raising healthy piglets

Raising healthy piglets from start right through weaning is a challenge you may not underestimate.

If you don't pay enough attention to it, it might impact the performance and health of your animals at later stages. Early weaning is still a widespread practice in the modern pig industry and piglets weaned at an early age suffer from different stresses. The sudden change in dietary regimens and management at weaning puts a heavy burden on the immature piglet.

This results in a disturbed immune system, increased susceptibility to diseases and can be considered as a main driver for on farm therapeutic use of antibiotics. A preventive strategy focusing on the immune system of the piglet is the future and natural approach which will help you to decrease therapeutic antibiotic consumption.  

Stressors in a piglet’s life 

We see that stress already starts at birth, a crucial period filled with risks. Therefore, piglets must be born strong and healthy to be able to cope with this stress.  At birth, piglets suffer from all kinds of pathogenic challenges due to an immature immune system. 

Once the piglet learned how to manage these challenges, another major stressor occurs: weaning. Although technological improvements in housing, nutrition, and management are available to minimize the stress, piglets are still weaned at unphysiologically early ages. The sudden change in dietary regimens at weaning places a heavy burden on the immature young piglet. The effects are aggravated by the immature immune system which has not developed a full response to cope with pathogens, resulting in disease (Table 1). It is clear that this impairment of the immune function, leading to diarrhea and even death, needs to be avoided. 

Table 1. Piglet’s diarrhea chart 

Focus on the sow 

It is not a surprise that a healthy sow has a better chance to farrow healthy piglets. All piglets are born with an immature immune system lacking protective immunoglobulins (Ig), as the placenta is impermeable for those proteins. Consequently, sow’s colostrum and milk quality are important for neonatal survival. Maternal Ig need to be provided via the colostrum, produced during the first 24 hours after farrowing, and via the milk (Table 1) to the piglet. The intestinal barrier of the piglet is permeable for those protective immune substances for the first 24-36 hours of life, allowing passage of IgG to the bloodstream. Consequently, the predominant Ig in colostrum is IgG, mainly active in serum, but in milk, the IgA concentration is predominant, protecting the intestinal mucosa of the piglet. By improving the immune status of the sow, the quality of the colostrum is enhanced, as transfer of antibody producing immune cells from the blood circulation to the milk is common in sows. Application of the correct vaccination program for sows, against circulating diseases during pregnancy and lactation is a start. Additionally, the immune system of the sow can be optimized using in feed solutions. The beneficial effect of beta-glucans in sow diets is known for a long time. Furthermore, new research has shown that piglets from a mother sow supplemented with an algal beta-glucan during pregnancy and lactation, have a better developed and more mature immune system after weaning. Supplementation of the piglets with the algal beta-glucan after weaning even reinforces that effect.  A screening of the circulating immune cells (T-cells¹) in those piglets blood showed more mature immune cells, like cytotoxic and memory T-cells, and less naive immune cells. Both cells are part of the cell-mediated immunity and are important in protecting the young piglet from disease. Consequently, fortifying the natural immune system of the piglet by feed ingredients is becoming an important strategy in managing piglet morbidity and mortality without antibiotics.   

¹T-cells are immune cells predominantly produced in the thymus. They recognize foreign particles (antigens) consequently playing an important role in identifying pathogens and triggering a further immune response resulting in a destruction of the invader. There are two major types of mature T-cells: the memory T-cell and the cytotoxic T-cell. They are formed out of preliminary or naive T-cells, which need to mature before they are becoming an effector cell (cytotoxic or memory). Cytotoxic T cells kill virally infected cells and tumor cells, while memory t-cells have a memory and respond directly to antigens by recruiting and stimulating antibody producing B-cells. 

Table 2. Composition of colostrum and milk. Colostrum provides easy accessible energy and an immune boost to the piglet, showed by the high energy and protein content.  

Secondly, a piglet’s gastro-intestinal tract only begins to establish a microbiota of its own after birth. The primary colonisation comes from secretions of the sow, faeces and the environment. The sow has no influence over which part of her microbiota she passes on to the piglet. A healthy sow with a balanced microbiome can supply large quantities of positive microbiota to her litter. Key here is to manage the intestinal flora of the sow, primarily for neonatal survival. To establish and maintain a positive microbiome as early as possible in a piglet’s life, do not supply a probiotic at weaning, start supplying it to the sow.

Continue with the piglet after weaning 

Weaners are suffering from intestinal and immune dysfunctions that can lead to reduced health and performance, increasing the on-farm antibiotic consumption. Identifying causes and targeted (nutritional) approach is of great importance to raise healthy performing pigs. One big advantage of weaning: piglets receive solid feed, which can be supplemented with health improving ingredients. Intestinal integrity is severely affected by weaning. Therefore, supplementation with ingredients supporting the intestinal lining, such as butyric acid needs to be considered. Weaners have a limited capacity for digesting protein in solid diets, as they do not have the ability yet to secrete sufficient HCl to obtain a gastric pH of 3 which is required for conversion of the inactive gastric zymogens into active protein digesting enzymes. Undigested protein in the gut could lead to microbial growth and subsequently to diarrhea. Reducing the buffering capacity of the feed with low protein levels and non-buffering calcium sources and additional free acids, can help to assure optimal protein digestion. Using multienzymes will help the piglet digest nutrients and free protein at the level of a more mature animal. Bridging the immunity gap – when the passive maternal immunity is gone and the piglet ‘s immune system is not well developed yet – is crucial to prevent diseases. Supplying those young animals with an immune modulating ingredient, a beta-glucan, can help them to develop their immunity and be more resistant to disease.  

Fig. 2. Managing the immunity gap in piglets 

A good start is half the battle 

To raise healthy piglets, a good start is really half the battle: starting with a proper management of the sow, and proceeding with a supportive strategy in the piglet, anticipating all stressful events in a pig’s life. Prevention is the key to reduce the on farm therapeutic use of antibiotics.  

Zn O, interested on Zn oxide replacement with sustainable solutions, download our peer reviewed paper.