Taking the next step in sow feeding

Since the early days of swine production, raising healthy animals and maximising the number of piglets produced have been top priorities in the industry. This continues to increase in modern husbandry, where optimising efficiency and performance are paramount. With a stronger focus on piglet production, the number of highly prolific sows has been gradually increasing in modern farms, but more piglets requires a new approach in housing and feed management, feed formulation and improved veterinary care.

Due to improvements in genetics, reproductive figures are increasing but a number of challenges still remain to be addressed in sow nutrition to improve piglet quality. Stillborn piglets, low birth weight and reduced viability are common piglet quality consequences of highly prolific sows. The number of piglets will influence the birth process and, without the correct feeding level and technique, less quality colostrum and lower intake can occur. Consequently, higher mortality in the first 3 days after birth and less uniformity within and between litters until weaning will occur when the sow is not fed according to her needs throughout lactation. In sows, nutritional deficiencies at weaning can lead to:

• low body condition with increased number of days weaning to oestrus,
• less pronounced mating behaviour,
• lower number of matured and
• less uniform follicles and higher risk of re-heats after mating.

Taking care of highly prolific sows begins with a nutritional plan that matches the growing, pregnancy and lactating phase necessities.

Gilt development

Gilts represent the most expensive investment on farm. As well as economic value, this also includes biosecurity, feed management and reproductive performance. Much progress can still be made on how to best introduce and feed gilts to reach maximum performance in areas such as growth rate, body composition, first mating and skeletal integrity.

Usually, special gilt rearing and development diets, taking into account mineral and vitamin levels, stop at the gestation and lactation phase, with the risk of incurring into nutritional deficiencies.

Feeding phases in gestation

Most feed formulations are based on cost efficiency; best practice dictates this should be led by the requirements of the different phases of the sow cycle. Modern sow production already takes this into account in terms of quantity, but further effort could be made to better match the needed nutrient profile.

In addition, this effort is being made in early or late gestation to adjust the amount of nutrients in the feed; the specific nutritional requirements of the period around birth still need to be addressed.

Protein and amino acids

Towards the end of gestation and around birth, the udder and foetal tissue need more proteins. Data suggests that the amino acid requirement in late gestation increases to a much greater extent than the energy requirement.

Research has also shown that increasing digestible lysine levels in the mid and late gestation period improved piglet quality. Both litter weight and average birth weight of the piglets increased and even colostrum protein content increased. Moreover, supplementing proteins has been shown to provide the sow with more backfat and better body weight development, which means more reserves for lactation.

An increasing focus is placed on the amino acid requirements for sows. The ability to use more than one phase feed during gestation means that amino acid requirements can be very specific in the periods where it is needed most: early gestation and late gestation. Moreover, gilts still develop body mass during their first gestation period and therefore need a different amino acid and energy profile than older parity sows.

Fibre

Fibre is one of the most important raw materials and nutritional aspects of sow nutrition. The ability to ferment fibre in late small intestine and large intestine is much higher for the mature sow. Early research has provided a few considerations to keep in mind when using fibre in sow diets, including:

• Sows fed high-fibre diets must eat more feed to meet their energy requirements, as energy content drops in the total feed.
• Digestion coefficients for high fibre ingredients are greater than those obtained with growing pigs.

More recent research work on fibre also shows beneficial effects on the birth process, which is essential for good quality born piglets. In this research, an increased fibre diet (7.6% vs 3.3% crude fibre) in late gestation shortened the birth process by 25 minutes. Consequently, the colostrum intake of the piglets improved and the duration for the piglet to go to the udder directly after birth decreased.

Fat and fatty acids

During lactation, more concentrated energy sources are needed to supply the necessary energy. Besides high starch materials, like maize and wheat, fat is the most important energy source. Sows are the most sensitive on palatability around farrowing and during lactation. Therefore, quality and source of fat are equally important.

The use of palm oil or linseed oil has been found to influence the duration of birth. Linseed oil fed during late gestation was found to have a positive influence on the duration of the birth process and litter size. Moreover, fish oil is known as a frequently used fat in late gestation and lactation diets, benefiting piglet quality. When fish oil was used in end gestation feed and transition diets, more active piglets were observed; for example, they were more vital and quicker at the udder and faster in drinking colostrum.

Vitamins

The importance of vitamins in high productive processes like birth, lactation and mating is often underestimated. Especially, in situations of oxidative stress, vitamins like E and C in combination with selenium can significantly help by catching the free radicals and balancing the process.

Around birth and the first days post-birth, oxidative stress is high and the vitamin E content in blood is the lowest, meaning extra anti-oxidant effect added in the feed would help the sow to improve her status on health support.

Studies have also shown the effects of dietary L-carnitine supplementation on the reproductive performance of sows. Most studies show consistently that L-carnitine supplementation to a sow’s diet increases piglet and litter weights at birth and enhances growth of litters during the suckling period.

There is evidence that carnitine influences the insulin-like growth factor-axis in sows and leads to greater placentae, which in turn improves intra-uterine nutrition. These effects may be responsible for higher birth weights of piglets.

DSM research has showed that the use of the 25-OH vitamin D3 (Hy-D) form in sow nutrition reduces the number of dead born piglets by 16%. Explained as the beneficial influence of more available 25-OH D3 in the blood in the calcium metabolism, it improves the uterine muscle contraction during birth, making the process more comfortable for the sow. Moreover, research has shown a 3% increase in birth weight and weaning weight of the piglets.

Conclusion

Besides the standard vitamins needed for maintenance and growth, specific parts of the sow cycle benefit from additional feed vitamins to support high prolific production.

As well as these specific nutrient requirements and raw materials, the total feed balance is key to successful sow feed and management. This requires a more holistic approach in sow nutrition where management, sanitary status and veterinary status are and should be combined.

Overall, there is enough research to show that sows need a more specific approach to feeding and nutrition. However, the latest advances in genetics for high prolific sows require an update of nutritional requirements.

References are available upon request.