**1.1 Parturition and birth complications**

About 10 years ago, a duration of 300 min was the upper limit for a physiological parturition [1]. Since then, litter size and farrowing duration increased steadily [1]. Nowadays, sows are hyperprolific (average litter size > 16) with an average farrowing duration of longer than 300 min [1–7]. This means that more than half of all parturitions are longer than physiologically. This rapid increase is concerning and leads to a high incidence of dystocia with subsequent negative consequences on piglet survival and sows' fertility and longevity [1–7]. An older survey showed that dystocia was mostly of maternal origin [8], whereas a newer survey identified that dystocia is nowadays almost exclusively due to maternal causes; with uterine inertia being the most common cause [9]. Primary uterine inertia, which is the reduction or complete absence of contractility of the myometrium already at the beginning of parturition, is due to hormonal abnormalities such as increased progesterone, and/or deficiencies of oxytocin and prostaglandin secretion and/or the presence of their receptors. Stress, e.g., caused by the inability of sows to express normal

nest-building behavior, is an important cause of primary uterine inertia [10]. Other causes are nutritional factors, e.g., diets low in fiber and high in energy leading to constipation and obesity [11]. Secondary uterine inertia is more common than primary inertia, usually occurring because of a prolonged farrowing particularly associated with a large litter size [12]. Idiopathic dystocia may occur because of the use of prostaglandin F2α and oxytocin to induce or control parturition [12].

Thus, in order to prevent birth complications, the needs of the sow must be fulfilled, stress must be avoided, and nutrition must be optimized. If not, hormonal imbalance will result into weak uterine contraction and subsequently dystocia. Therefore, active birth management starts before birth in order to prevent this and continues during birth when proper response to hormonal imbalance is needed.

### **1.2 Colostrum and piglet survival**

Sufficient mammary gland development is important for optimal colostrum production and therefore prevention of piglet mortality [13]. Pre-weaning piglet mortality rate was 7.1% (reference value: <11%), when piglets ingested more than 200 g of colostrum, and increased to 43.4% when intake was less than 200 g [14]. Thus, piglets need at least 200 g of good quality (>50 mg IgG/ml) colostrum. Unfortunately, colostrum yield is highly variable, averaging 3.5 kg and ranging between 1.5 and 6.0 kg [15, 16]. This means that some sows will not produce enough colostrum for their piglets. Further, even though the average yield might be enough for a litter of average size (about 17–18 piglets), it can be difficult for many sows to adequately nurse more than 10–11 piglets without human assistance (such as assisted suckling, cross fostering, movement to a nurse sow, split or suckling assistance) [17]. Thus, factors affecting mammary gland development and colostrum production need to be identified and optimized [13]. One of these factors is the hormonal status of the sow, which can be because of stress, suboptimal feeding, and husbandry during the week(s) before parturition.

Besides the production of a sufficient amount of good quality colostrum, there are further challenges. One of them is the length of the colostral phase. Colostrum is produced only during the first day after the start of parturition. Already after the first 6 h, the IgG content in colostrum is halved [18]. Since large litters can easily extend farrowing beyond 6 h [1], many piglet are born too late in order to get an appropriate amount of good quality colostrum. Therefore, the goal at each parturition is not only to optimize colostrum production by the sow but also the colostrum uptake by neonate piglets. Neonate piglets must acquire a sufficient amount of immunoglobulins from ingested colostrum for energy and passive immune protection [19]. The concentration of immunoglobulins in the plasma of piglets shortly after birth correlates positively with their survival rate [20]. Thus, it is necessary to assess colostrum quality and colostrum intake by piglets throughout parturition in order to reduce piglet pre-weaning mortality. This is especially important if mammary gland development is low and/or parturition is prolonged.

#### **1.3 Postpartum dysgalactia syndrome and sows' fertility**

PDS is the most important puerperal disease and is characterized by insufficient colostrum and milk production by the sow during the first days of lactation [21]. As consequence, colostrum and milk intake by piglets is reduced, and therefore their mortality increased [21]. Further, PDS negatively affects subsequent reproductive health of the sow [4]. Unspecific symptoms for PDS include fever (>40°C), loss of appetite, and lethargy [21]. Specific symptoms are dysgalactia and vulvar discharge syndrome [21]. Causes of the vulvar discharge syndrome are vaginitis, endometritis, and cystitis [22].

**91**

**Table 1.**

*gland development and colostrum production.*

*Tools and Protocols for Managing Hyperprolific Sows at Parturition: Optimizing Piglet Survival…*

An increasing incidence for PDS of up to 34% was recently reported [23], which is connected with the increase in litter size and farrowing duration [3]. In one study, the percentage of sows with fever during the first 24 h postpartum increased from 40 to 100%, when the farrowing duration increased from less than 2 to more than 4 h [24]. Furthermore, until the third day postpartum, the percentage of sows with reduced appetite was higher in sows with a farrowing duration of more than 4 h than in sows with less than 4 h [24]. In another study, 85.9% of sows with puerperal disease had farrowing durations of more than 6 h, whereas 78.8% of healthy sows

Both prolonged farrowing and PDS share mutual risk factors [11, 21]. Further, both are connected with a decrease in subsequent fertility [4, 5, 26]. Thus, prevention of birth complications and proper birth management will also prevent postpar-

Proper management of hyperprolific sows in order to optimize piglet survival and sow's reproductive health starts before parturition. The aim is to improve mammary gland development and colostrum production as well as to prevent birth complications and puerperal diseases. In order to do so, optimizing environment, management, and nutrition is highly important. **Table 1** provides a checklist for preventive measures.

*Checklist for prevention of birth complications and puerperal diseases as well as for improving mammary* 

tum disease and therefore optimize subsequent reproductive performance.

*DOI: http://dx.doi.org/10.5772/intechopen.91337*

completed parturition in less than 3 h [25].

**2. Tools and protocols before parturition**

*Tools and Protocols for Managing Hyperprolific Sows at Parturition: Optimizing Piglet Survival… DOI: http://dx.doi.org/10.5772/intechopen.91337*

An increasing incidence for PDS of up to 34% was recently reported [23], which is connected with the increase in litter size and farrowing duration [3]. In one study, the percentage of sows with fever during the first 24 h postpartum increased from 40 to 100%, when the farrowing duration increased from less than 2 to more than 4 h [24]. Furthermore, until the third day postpartum, the percentage of sows with reduced appetite was higher in sows with a farrowing duration of more than 4 h than in sows with less than 4 h [24]. In another study, 85.9% of sows with puerperal disease had farrowing durations of more than 6 h, whereas 78.8% of healthy sows completed parturition in less than 3 h [25].

Both prolonged farrowing and PDS share mutual risk factors [11, 21]. Further, both are connected with a decrease in subsequent fertility [4, 5, 26]. Thus, prevention of birth complications and proper birth management will also prevent postpartum disease and therefore optimize subsequent reproductive performance.
