Guide to Pig Management: Gestation (Part 2)
Although gestation appears to be one of the simpler stages of the pig production cycle, management and nutrition can have a big impact on herd productivity both for the current and the following generation of animals.03.06.2021
• Recovery after parturition, especially the first parturition, and preparation for the next lactation is key to optimizing performance of the herd. In some instances, skipping a heat and allowing the sow to recover may be beneficial in the long term.
• Conditions in the loose sow pens should be strictly monitored to meet the requirements of the gestating sow. This includes meeting the nutritional requirement of the sow and providing enough access to fresh water.
• Mycotoxins can negatively impact sow performance and decrease the fertility of the female fetuses. Mycofix® is the most complete mycotoxin risk management available to pig producers.
Recovery and preparation for the next lactation is not always easy for a sow, especially if more than 13% of their body weight was lost during the previous lactation. In some countries, skipping a heat after first parturition or when a challenging lactation has caused the sow to become very thin is a fairly common practice. This gives the sow time to recover and prevent second parity syndrome. Waiting until the following heat (21 days) to service the sow may be preferable to a second parity of only a few piglets.
Waiting until the following heat may be preferable to a second parity of only a few piglets.
Sows are usually housed in individual crates for 30 days following insemination. Once pregnancy is confirmed, they are moved to loose sow pens. They should be grouped according to weight to keep hierarchy fighting to a minimum and to allow all animals equal access to feed. Transponders can be used to ensure that all loose sows are fed according to their feeding schedule. The loose sow system has proven beneficial in terms of welfare, and for maintaining sow muscle tone which makes calcium metabolism more effective leading to positive effects at farrowing. Gestating sows require:
- Temperatures of 16 – 20 °C
- Dry floors
- One nipple/bowl drinker per 10 sows
- Clean, fresh water at a flow rate of at least 2 l/min
- 8 hours of light at an average of 250 lux.
The sow's hooves should also be given attention during the gestation period.
As shown in Figure 1, requirements for the embryo and maternal development are initially low, then increase exponentially. In practice however, feed levels can be higher than the actual requirements in the first weeks of gestation to compensate for the loss of body condition in the previous lactation. However, extra feeding during this period cannot compensate an excessive loss of condition.
During late gestation, when requirements are higher, feed must be increased to meet demand depending on body weight and litter size. Bump-feeding at the end of gestation is of no benefit to the sow and can cause periparturient hypogalactia syndrome and vulvar edema. In general, feed intake during gestation is negatively correlated with feed intake in the subsequent lactation.
Fiber is very important during gestation as it dilutes the energy density of the feed, causes an effect of satiety and calms the sow, which is important in group-housed animals. Sows can also ferment soluble fiber and increase their production and absorption of short-chain fatty acids (SCFA). Diets that contain soluble fibers can stabilize glucose levels in the blood, increase SCFA absorption and potentially improve colostrum production. Finally, soluble fibers can have a laxative effect and prevent peripartum constipation.
During gestation, the nutritional target is to support embryo development to increase piglet birth weights and for high-quality colostrum production.
The gestation period seems to be one of the least complicated in the production cycle, but insufficient water consumption during this period can cause numerous problems to the sow's urinary system. Free access to water and a sufficient number of drinkers must be available to all sows after insemination in both group houses and in individual stalls. This reduces the risk of competition between animals that are still trying to establish a hierarchy in the newly formed group. Aggression between sows can be significantly reduced by providing a constant water supply.
Zearalenone (ZEN) poisoning can cause abortion during the first 14 days after insemination, resulting in the invisible loss of some piglets. Ergot alkaloids can also cause abortion at any stage of gestation as can T-2 mycotoxin (Weaver et al., 1978). ZEN can cross the placenta and affect female fetuses, jeopardizing their future fertility (Alm et al., 2006). ZEN also causes vaginal prolapse around farrowing (Supakorn et al., 2017). It is therefore important to eliminate mycotoxins during gestation to prevent these problems. Mycofix® is the most state-of-the-art and complete mycotoxin risk management solution for protecting animal health.
Mycotoxins must be eliminated during gestation to avoid problems including abortion, vaginal prolapse, and the fertility of female fetuses.
Silibinin, a polyphenolic flavonoid isolated from the milk thistle Silybum marianum inhibits lipopolysaccharide (LPS)-induced macrophage activation and nitric oxide production. Phytogenic supplements such as Digestarom® improve digestion and help reduce the risk of constipation. They also reduce the level of LPS in the gut, as well as levels of biogenic amines. Biogenic amines can have a direct impact on the uterus due to its anatomical proximity to the gut and the blood vessels that it shares with the rectum. The end result is a less functional uterus.
Alm, H., Brüssow, K.-P., Torner, H., Vanselow, J., Tomek, W., Dänicke, S. and Tiemann, U. (2006). Influence of Fusarium-toxin contaminated feed on initial quality and meiotic competence of gilt oocytes. Reproductive Toxicology 22(1). 44-50.
NRC. (2012). Nutrient requirements of swine. 11th rev. ed. Washington, DC: The National Academies Press.
Supakorn, C., Stock, J.D., Hostetler, C. and Stalder, K.J. (2017). Prolapse incidence in swine breeding herds is a cause for concern. Open Journal of Veterinary Medicine 7(8). 85-97.
Weaver, G.A., Kurtz, H.J., Mirocha, C.J., Bates, F.Y., Behrens, J.C. and Robison, T.S. (1978). Effect of T-2 toxin on porcine reproduction. The Canadian Veterinary Journal 19(11). 310-314.