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Subunit DIVA Vaccine for Lawsonia Intracellularis Sows Promise

Researchers with VIDO-InterVac are developing a safer easily identifiable vaccine to protect pigs from Lawsonia intracellularis. Lawsonia intracellularis, a bacteria found in about 90 percent of the world's swine herds, causes Ileitis, a swelling of the intestine in pigs. Researchers with VIDO-InterVac are developing a subunit DIVA vaccine which will allow the differentiation of infected from vaccinated animals.
 
Dr. Heather Wilson, a research scientist with VIDO-InterVac, says researchers are now narrowing down the choices of proteins to include in the vaccine.
 
Clip-Dr. Heather Wilson-VIDO-InterVac:
 
We've done a couple fancy little molecular things to identify the proteins of interest and we've found 11 to choose from out of the hundreds and hundreds that are in the bacteria and, from those 11, we’ve further narrowed them down. Some of them are better at triggering an antibody response, some are better at triggering a t-cell response.
 
We're further narrowing that down so that we can do some challenge studies to see if subunit protein one, two or three alone or together actually show a good protection from disease. Now what we do is we just keep running trials and changing the adjuvant platform, which is something that you add to the vaccine to try to trigger an antibody or a t-cell response or both.
 
We need to play around with the concentration of subunit proteins that we add, the routes of immunization. Ideally, we would put it in dinking water or have it as a mist or something like that so it could be easy to administer. All of these things is a new set of experiments and data collection and then try to get together a good package showing that we've got a very nice vaccine that is protective.
Source : Farmscape

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US Soy: Pig growth is impaired by soybean meal displacement in the diet

Video: US Soy: Pig growth is impaired by soybean meal displacement in the diet

Eric van Heugten, PhD, professor and swine extension specialist at North Carolina State University, recently spoke at the Iowa Swine Day Pre-Conference Symposium, titled Soybean Meal 360°: Expanding our horizons through discoveries and field-proven feeding strategies for improving pork production. The event was sponsored by Iowa State University and U.S. Soy.

Soybean meal offers pig producers a high-value proposition. It’s a high-quality protein source, providing essential and non-essential amino acids to the pig that are highly digestible and palatable. Studies now show that soybean meal provides higher net energy than current National Research Council (NRC) requirements. Plus, soybean meal offers health benefits such as isoflavones and antioxidants as well as benefits with respiratory diseases such as porcine reproductive and respiratory syndrome (PRRS).

One of several ingredients that compete with the inclusion of soybean meal in pig diets is dried distillers grains with solubles (DDGS).

“With DDGS, we typically see more variable responses because of the quality differences depending on which plant it comes from,” said Dr. van Heugten. “At very high levels, we often see a reduction in performance especially with feed intake which can have negative consequences on pig performance, especially in the summer months when feed intake is already low and gaining weight is at a premium to get them to market.”

Over the last few decades, the industry has also seen the increased inclusion of crystalline amino acids in pig diets.

“We started with lysine at about 3 lbs. per ton in the diet, and then we added methionine and threonine to go to 6 to 8 lbs. per ton,” he said. “Now we have tryptophan, isoleucine and valine and can go to 12 to 15 lbs. per ton. All of these, when price competitive, are formulated into the diet and are displacing soybean meal which also removes the potential health benefits that soybean meal provides.”