Authors:
Jordi Camp (PIC® Europe nutrition team) Pablo Magallón, Maria Ros, Patricia Blanco, Serhii Shevchenko, Adrian Lopez, Isaac Huerta (PIC® Southern Europe technical services).
Introduction
The article, which will be published in 2 parts, focuses on management and nutrition strategies to address post-weaning challenges in pig farming. Weaning is a critical period in the life of piglets, marked by adaptation to a new environment and changes in diet that can affect their health and growth. Post-weaning diarrhoea (PWD) is a significant concern in the pig industry, exacerbated by stricter environmental regulations.
Pre-weaning management, such as access to colostrum and early socialisation, can influence piglet adaptation to weaning. Age at weaning and body weight are key factors related to the incidence of DPD. In addition, the health status and integrity of the intestinal tract are crucial in the prevention of post-weaning diseases.
Nutritional strategies include reducing crude protein, using highly digestible sources of protein, balancing amino acids and adjusting stomach pH. In addition, vitamins, minerals, fibre, particle size, lactose and feed additives are considered to improve gut health and reduce DPD.
In summary, addressing post-weaning challenges requires a holistic approach combining management and nutrition strategies to ensure healthy piglet growth.
Management and Nutrition Strategies for Post Weaning Challenges
Weaning is one of the most challenging periods in a pig’s life (Campbell et al., 2013). At weaning, piglets must adapt to a new environment in combination with impaired gut and immune function (Huting et al., 2021), which can ultimately affect pig health, growth, feed intake and behaviour (Campbell et al., 2013). Post-weaning diarrhoea (PWD) is a multifactorial disease and one of the most relevant in terms of treatment cost, production performance and mortality in pig farms (Bonetti et al., 2021). In addition, more restrictive environmental regulations are being issued in several countries or regions, such as restrictions on the use of antibiotics or zinc oxide, which makes this period even more challenging.
DPD needs to be evaluated considering management, health and nutritional factors. This article will focus on management and nutrition, which play a key role in the post-weaning period.
Management Strategies for Post Weaning Challenges
Weaning is a very sensitive and stressful time for the piglet, as it undergoes a number of important and abrupt changes:
- Loss of maternal protection and sudden separation from its mother.
- Interruption of the transmission of antibodies from the mother to the piglet through the mother’s milk, with the consequent loss of passive immunity. The so-called ‘immune window’ occurs, which makes the piglet susceptible to pathological problems in the post-weaning period.
- Change of location, almost always by vehicle transport and sometimes over long distances.
- Frequent changes of rearing companions, becoming part of larger groups than the original litter, with consequent struggles to re-establish social hierarchy.
- New feeding systems, new hoppers and drinkers with mechanisms that require learning and handling.
- Abrupt change from warm liquid feed to cold solid feed, which are in turn less digestible diets.
- Increased water requirements.
- Major changes in feed supply: from feeding in suckling cycles every 40-60 minutes, to having ad libitum feed available to them that most of the time they have barely tasted.
Pre-weaning management strategies
Post-weaning challenges can be managed before weaning. There are a number of factors for which a set of pre-weaning strategies can be considered to improve performance in the lactation period, reduce weaning stress and achieve better adaptation to the weaning period. Birth and weaning weights are related to the incidence of scours and mortality in the transition phase. Piglets born and weaned prematurely will have more difficulty in coping with the weaning period. To avoid a high number of light piglets at weaning, it is important to ensure good colostrum and milk intake, good management of piglets picked up and sows in more prolific sow lines, and to provide supplementary feed during lactation, such as milk replacers/complements and feed to improve piglet weight and adaptation to the weaning period. The use of creep-feed is recommended during lactation because its consumption promotes the piglets’ familiarisation with the type of feed they will receive in the future and, in turn, stimulates the maturity and enzymatic capacity of the intestinal tract (Pluske et al., 2007).
Early socialisation can also help to reduce weaning stress when pigs are mixed with other litters, which leads to stressful situations and/or fights that can cause poor production performance, health and animal welfare. In addition, good sow management will be important to improve the farrowing process and milk production during lactation, which will result in a better adapted piglet at weaning.
Post-weaning management strategies
At weaning, piglets should have ample access in terms of water and feed. In addition, adequate housing space with optimal temperature, ventilation and humidity should also be considered. Please refer to the PIC® Wean to Finish Manual to follow the PIC® recommendations.
Age at Weaning – Body Weight – Intestinal Maturity
Intestinal maturity and intestinal health are terms closely associated with the age of the piglet at weaning and the feed intake capacity at that time. Age at weaning is a key factor related to adaptation and post-weaning challenges. In general, pigs weaned at an older age have better adaptation to weaning and a lower incidence of post-weaning syndrome compared to immature pigs. Depending on weaning age and body weight, four situations can be considered (Table 1).
Table 1. Summary of weaning situations.
| Low Weaning Weight | High Weaning Weight | |
| Physiological Age Inadequacy | Situation 1: very unfavourable | Situation 2: unfavourable |
| Physiological Age Appropriate | Situation 3: unfavourable | Situation 4: optimal |
Situation 1: very unfavourable
This is the most unfavourable situation, as the piglets are not only immature but also underweight. These piglets are very sensitive to the lack of ‘thermal comfort’. They have an immature digestive system, so they need highly digestible ingredients, and the feed intake achieved at weaning is extremely low, so they will need nutrient-rich diets.
Situation 2: unfavourable
Piglets with adequate weaning weights, but inadequate intestinal maturity. This situation usually occurs with the heaviest piglets in the litter, the so-called strict sucklers, who do not recognise the new feed source at weaning, leading to a period of anorexia and weight loss. In this situation, it is key to get as many piglets as possible started early on solid feed with strategies such as slow feeding, use of mash or wet feed, stimulating exploratory behaviour by feeding small amounts of feed several times a day, encouraging water intake, and using high quality, digestible diets and feed supplements to encourage intake.
Situation 3: unfavourable
In this case, the piglets are of low weight, but of appropriate physiological age. Normally, the youngest animals in each litter consume and explore the feed to satisfy the nutritional intake that they do not find in the mother’s milk. Thus, in the transition they are already familiar with the consumption of solid feed and show a better adaptation. In this type of piglets, the main disadvantage is that they are very sensitive to environmental comfort, as they have low body reserves of glycogen and fat. Therefore, in this case, good facilities and environmental conditions become very important.
Situation 4: optimal
In this case these are piglets with high weaning weights and adequate physiological age or intestinal maturity. These piglets will have a more favourable starting situation than the rest, because, if the environmental conditions and facilities are adequate, and the feed is of good quality, they will have a good start at weaning.
Health
The most important factor affecting mortality is the health status of the piglets at weaning. The piglet progressively loses passive immunity after weaning before it has fully developed acquired immunity, so if piglets have conflicting health backgrounds they will suffer from multiple problems and increased digestive processes and therefore increased post-weaning mortality. Health controls such as vaccination protocols should be considered. Proper cleaning and disinfection of rooms will be important to reduce the incidence of post-weaning syndrome. This procedure consists of cleaning, disinfection and drying. Previous studies have pointed to the drying process as key to reducing microbial populations.
Latency period
From the beginning of weaning, high and regular feed consumption by the piglet is necessary to ensure the integrity of the intestinal microvilli. In the first days the feed intake should be at least 150 g/day, so that the piglet can maintain its body mass reserves. It is common that the piglet loses weight in the first days because it takes too many hours to start eating. Some authors refer to this period as the latency period, which is the time from weaning until the piglet reaches a regular feed intake. As discussed above, the time at which piglets start eating after weaning will also affect their subsequent performance. Bruininx et al. (2001) observed that 20% of piglets take more than 20 hours to start. Fluctuations in feed intake cause the piglets’ digestive microbiota to become unbalanced and pathogenic bacteria such as E. coli proliferate, leading to diarrhoea and promoting the expression of digestive problems such as oedema disease. Therefore, piglets that take longer to start eating may have a higher incidence of digestive problems in the post-weaning period. In addition, it is important to take into account the time piglets spent without feed during their transfer from the farrowing house to the transition room. In addition, the management of the whole weaning process and transport should also be considered, as it will have an impact on the post-weaning behaviour and performance of the piglets.
Different feed management strategies could be followed to improve post-weaning feed intake. These strategies are provided in the section on pre-weaning and post-weaning feeding strategies.
Water
Water is one of the main nutrients for the piglet. Therefore, the quality of the water should also be considered. On farms with digestive problems in piglets at weaning, it is advisable to feed water with organic acids that lower the pH around 5. Acidification of water is a good strategy that could help reduce the incidence of PWD. Refer to the PIC® Wean to Finish Manual for water guidelines.
