To increase the efficacy of pig breeding, it is important to increase the number of piglets weaned per sow per year. This is generally achieved by using hyper-prolific hybrids, where it is not unusual to have more than 20 piglets born alive per litter. However, additional husbandry and feeding solutions must be implemented to successfully raise these big litters.
Issues related to selection for increasing litter size
The past 30 years have yielded great results in genetic selection for increasing litter size in modern hybrid sows. Parallel to the increase in litter size, the number of stillborn piglets and pre-weaning mortality also increased (Table 1). But an increase in the number of piglets born will only mean greater profits if the piglets reach the weaning age.
- Table: Average number of live born and pre-weaning mortality of piglets in the Netherlands in 1996 and 2022
Source : Publications of Kengetallenspiegel, AgroVision B.V., Apeldoorn, Netherlands
Average farrowing duration for modern hybrid sows is 3.6 hours (Nam and Sukon, 2020). Large litter size may also negatively affect the process and the duration of farrowing. Prolonged duration of farrowing not only increases stillbirths by increasing the risk of ruptures of the umbilical cord and asphyxia (Mota-Rojas et al., 2006), but also affects vitality, colostrum intake, growth and chances of survival in piglets negatively (Langendijk et al., 2018; Oliviero et al., 2019). A prolonged farrowing also means a bigger stress for the sow, and it is associated with issues such as decreased colostrum production, retained placenta, post partum dysgalactia syndrome, problems with uterine involution and further reproductive issues (Peltoniemi et al., 2016). Based on this we can conclude that the duration of farrowing is a highly important index in swine breeding.
The importance of the transition phase, aspects of designing a feeding concept
The nutritional requirement of gestating and lactating sows differs greatly because of the dynamic changes in the physiological requirements. These significant changes are reflected in the ingredients and nutritional composition of the feeds. Because of the difference in the intensity of metabolism during the different phases, it is easy to provide energy in excessive amounts to the gestating sow. In order to avoid this and maintain the optimal body condition for breeding, sows must be fed a restricted diet that is low in energy and protein. In this phase, fibre fermented in the hind gut is an important source of energy. The energy requirement of the sow increases significantly after farrowing, since they need energy for milk production while being in a state of energy deficit. The increased energy requirement of lactating sows justifies a diet with a high energy content. Special attention must also be paid to providing an appropriate lysine to energy ratio, as well as maximising feed intake.
In most cases the change from gestation feed to lactation feed happens abruptly when the sows are transferred to the farrowing unit, without a transition period. The last few days of gestation and the first week of lactation is a stressful period for the sow partly because of the change of housing and the abrupt feed change. Providing a transition (gradual change) between the two nutritional phases is therefore of major importance. Transition feeds are similar to lactation diets regarding their crude protein content, while the fibre content is closer to that of gestation diets. It contains an increased amount of fibre from different sources, the importance of which has long been recognised in the nutrition of gestating sows and in preventing obstipation around farrowing, while its importance in providing energy to hyperprolific sows during farrowing represents a new concept. Up to 25% of the maintenance energy requirement of sows with high genetic potential is provided by fermentation in the hind gut. Microbial fermentation of fermentable fibres in the hind gut of the sow results in the production of volatile fatty acids (acetic acid, propionic acid and butyric acid), and these compounds play a role in further energy generating processes. This metabolic pathway means that energy generated from fermentation is absorbed slowly and gradually. Surplus energy generated this way might be available for the sow for an additional 24 hours (Potthast, 2022). This is why we must focus on providing fibre sources with different fermentation characteristics in sow diets (Figure 1).
Figure 1. Classification of different fibre sources according to fermentation characteristics
We can also evaluate the water binding and swelling capacity of different fibre sources to induce satiety in sows and avoid overfeeding that can lead to an increase in body condition. Fibre can increase gastric and intestinal capacity, which then can lead to increased feed intake during lactation.
Besides choosing the appropriate dietary fibre sources, the correct electrolyte balance is also critical in sow feeds because of its role in calcium (Ca) metabolism. Inappropriate electrolyte concentrations might result in slow Ca-mobilisation through hormonal pathways and lead to Ca deficiency. The dietary electrolyte balance is typically lower in transition and lactating sow feeds compared to gestation feeds, which is extremely important in promoting Ca mobilisation from bones and improving uterine contractions, thus exerting a positive effect on the farrowing process as well as milk production and milk flow (Helvoirt-Kremers, 2015).
Parto-Plusz – a solution to overcome the challenges
Apart from challenges related to genetic selection, some issues might arise from technological deficiencies: in many cases Hungarian farms lack the infrastructure that would allow the use of a transition feed. Bonafarm-Bábolna Takarmány Ltd. has introduced Parto-Plusz, a feed supplement for the transition period designed to prevent and treat the previously mentioned problems. Parto-Plusz was developed specifically for use in the transition period. The product should be fed for a few days between the time of transfer to the farrowing unit until farrowing to reach the desired effect. Parto-Plusz supports the farrowing process, contributes to decreasing the length of the farrowing process and can increase the number of live born piglets and their vitality. We formulated the supplement to contain ingredients with high energy content as well as fibre sources with different fermentation characteristics. These ingredients help the sow maintain a stable blood glucose concentration. Fibre improves fecal consistency and prevents obstipation that might act as a mechanical obstacle during farrowing. The probiotics in Parto-Plusz promote the growth of lactic acid producing bacteria, thus contributing to maintaining a healthy gut flora. The vitamin D source (25-OH-D3) specifically chosen for its biological efficiency promotes uterine contractions, milk production and milk flow through Ca mobilisation.
The number of piglets weaned per sow is one of the most important factors determining the profitability of swine production, and thus it is our main goal to maximise this number. However the continuous efforts to increase the performance of the sows should always include dietary efforts, especially during the critical period around farrowing. The Parto-Plusz transition supplement of Bonafarm-Bábolna Takarmány Ltd. provides a solution to addresses these challenges. The special ingredients of the product contribute to ensuring profitable production through the improvement of reproductive performance.
Literature is available at request.
Fédra Borbély
junior product manager
Bonafarm-Bábolna Takarmány Ltd.
