See Purina® Outlast Supplement in action. Watch as Dr. Robert Jacobs, Purina PhD research equine nutritionist, demonstrates how a horse’s stomach would respond to a feeding of Outlast Supplement.

In this short experiment, Purina® Outlast Supplement raises the pH level of a simulated equine stomach environment from a harmful pH of 2 to a safe pH level of 6.3 in just two minutes. This demonstrates that it outperforms alfalfa and competitive products on the market. Ready to put Outlast Supplement to the test? Start your Feed Greatness™ Challenge at

Welcome to the Equine Research Unit here at Purina Animal Nutrition Center. My name is Dr. Robert Jacobs, a research equine nutritionist, and today, I’m here to demonstrate our new gastric support supplement, Outlast.

Outlast is designed to provide gastric support and help comfort the horse’s stomach. Horse are herbivores. That mean they are designed to consume forages eighteen to twenty hours a day. Modern management practices, however, require that we feed our horses concentrate and meal feed them throughout the day. Outlast is designed to support the overall health of the gastric environment in the horse.

Today, we’re going to demonstrate how the horse’s stomach would respond to a feeding of Outlast. In this beaker we have a constantly churning fluid at a pH right around 2. This is the constant pH of the horse’s stomach when they’re at a fasting state. Additionally, we’ve heated this environment to approximately 37 degrees Celsius. This would be the internal body temperature of the horse.

We’re going to take Outlast, our gastric support supplement, and grind it up. You can see what we’ve done here to stimulate the chewing that the horse would do before this supplement would reach the gastric environment or into the stomach of the horse. We’re going to put this into that gastric environment, then we’re going to show you exactly what happens to the pH.

I want to focus on this pH meter. We put this gastric buffer into this gastric environment. So we’ll simply put this in here. We’ll give it a little bit of a mix, again to help stimulate what would happen in the horse’s stomach. Then we’ll set this timer to about two minutes.

We’ve done a significant amount of lab work at the Purina Animal Nutrition Center, as well as at universities throughout the country to better understand how Outlast buffers the equine stomach. We’ve done in vitro trials similar to what you can see in this setup here as well as in vivo trials. Here we’ve fed this supplement to hundreds of horses and examined what happens with the pH of the gastric environment. We also observed what happens to the overall health of the horse’s stomach.

We’ll wait until this gets to its buffering capacity at about two minutes. Then we’ll take another pH reading to see exactly how this gastric support supplement works.

You can see here, after two minutes we’re going to take another pH reading on our simulated gastric environment. So, we look here at this pH meter, and you can see after only two minutes, the pH has already risen to approximately 6.3. Well above the threshold of four which we generally consider a buffered stomach environment.

Remember, a higher pH is indicative of a lower acidity in the stomach. This is what we would want to see to provide the gastric comfort and the support that Outlast is designed to do.

Outlast gastric support supplement is different from some of the other products that are currently on the market. It acts quicker, in only two minutes you can see the pH rose substantially. Additionally, it acts longer, as we saw in our in vivo as well as our in vitro trials. Plus, it has a significantly higher buffering capacity and buffering ability, as is demonstrated here in these test tubes.

In these test tubes, you can see a representation of how much acid a single serving of any one of these supplements. This includes Outlast, which is able to buffer in a simulated gastric environment. You can see here in these tubes that Outlast is able to buffer a significantly larger quantity of acid than even alfalfa or some of the other competitive products. This is demonstrated by these different colored tubes.



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