Changes in swine nutrition over the past two decades have been sweeping, and the namesake for the London Swine Conference’s new CFM de Lange Lecture in Pig Nutrition played a pivotal role.
“Kees (de Lange) was certainly a pillar in the swine nutrition community,” Mike Tokach, a Kansas State University animal sciences and industry professor, told delegates to the annual conference held in London earlier this year.
Tokach, the annual lecture’s first speaker, said the late de Lange, a University of Guelph professor who specialized in swine nutrition, “was held in high regard for not only for his basic research side (but also) because he was one of those rare souls who was able to take basic research information and make it understandable to people at the barn level.”
De Lange died last year.
Tokach touched on many breakthroughs in swine nutrition, such as changes in expressing and determining nutritional requirements.
Modified net or metabolizable energy value calculations, for example, are increasingly replacing measures such as digestible energy or metabolizable energy. The new approaches that are beginning to be referred to as productive energy promise more accurate results than their predecessors, which tend to overestimate the true energy use of food ingredients, Tokach said.
In terms of amino acids and phosphorus, the industry has moved toward standardized measures derived from how much a pig would realistically digest and away from measures based on calculations of total amounts contained in a feed or by subtracting what remains at the other end of the digestive system (but not accounting for the other ways these food components could be lost along the way.)
Changes in research methods have also sped advances in nutrition, he said, noting that in 1995, there were only four production research facilities in the United States. Today, Kansas State University alone manages 17 production research facilities.
“These field research facilities allow for more robust testing of ingredients and additives in production systems,” Tokach said.
The facilities also allow field evaluations of the growth and reproductive models that nutritionists increasingly use to estimate feed requirements for different levels of productivity.
Tokach highlighted several other breakthroughs over the past two decades:
- At one time it was thought that growth rates in the nursery are linked to finishing growth rates. It’s now known that weaning age and weight are key factors. Later weaning ages or weights allow important changes in the animal’s gastrointestinal tract to occur and also lead to better immune and digestive function. These factors in turn create better potential to reach a heavier market weight.
- As the trend to increasing weaning age grows, reliance on expensive nursery diets diminishes. “The move towards older weaning ages is still underway in the North American swine industry and average weaning age will likely continue to increase as antibiotic use decreases,” he said.
- Other research has revealed that a change in nutrition prompts a change in growth performance only as a specialized diet is fed. It won’t continue to affect performance after the pig is switched to a common diet. The new understanding “has greatly reduced nursery diet complexity and cost for many production systems.”
- Over the past two decades producers have increasingly added zinc to early nursery diets to reduce diarrhea and promote growth. However, pressure to curtail the practice grows. There is an issue of toxicity for animals if pharmacological concentrations are used for too long. There are also concerns that its use could increase methicillin-resistant staphylococcus aureus. Tokach urged industry to be proactive by using zinc only where “the greatest benefits are observed.”
- Changes to feeder design, such as the advent of automatic feeding systems, allow better access for animals, improve their feed intake and reduce the labour required to provide the feed.
- The availability of dried distillers grain with solubles has “changed feeding programs in many North American production systems more than any other ingredient over the last 20 years,” he wrote in a paper accompanying the lecture. The use of DDGs has also triggered understanding of other areas of swine nutrition, the effect of the source and feeding duration of fat on the animal’s fat quality being one.
- On Jan. 1, most antibiotics could no longer be used to promote growth in finishing pigs in the United States. “Oversight and cost of compliance will continue to increase and apply further pressure on antibiotic use,” he wrote.
- Mycotoxin issues appear to be on the rise for the industry, perhaps because of the adoption of new technologies in corn production or improvements in how myco-toxins are tested and measured. There are some solutions on the horizon, but they are limited, he said.
Looking back reveals “just how far we’ve come with improving production in the industry,” Tokach said, noting that in 1994 in the United States, producers marketed 14 pigs per sow per year. In 2015, that number had grown to 22 on average.