Unlocking the Role of B Vitamins in Receiving Cattle

Timestamps & Summary Chris Gwyn (02:04)Could you share with the audience why B vitamins would be important to receiving cattle in particular?Dr. Stephanie HansenAbsolutely. If we go back and look at the NRC guidelines, we've really ignored two classes of vitamins, vitamin C and vitamin B. Cattle are able to make vitamin C from glucose in their liver. […] Not a lot of work is focused on that because the assumption has been that the animal can make it, it's fine. Similarly, they get most of their B vitamins from rumen microbial synthesis. And so, again, a lot of the requirements were largely ignored, or potential requirements, because the thought has been: Well, his bugs make it for him, so he's fine. […]Chris Gwyn (04:19)What do they do to a feed lot receiving cattle that would be important in their overall performance, health, productivity, profitability in the end?Dr. Stephanie HansenThe way that I teach this to my nutrition students is that if you think about the macros like protein and carbohydrates and lipids, often the things that we formulate rations for initially, those are like the bricks in a wall. If you stacked those bricks on top of each other, they're pretty robust, and they're a big chunk of that wall. But you could push those bricks over with a finger because there's nothing holding them together. If you think about minerals and vitamins in water as collectively making the mortar that you could put between those to hold it together, and you let it dry, now it'd be pretty hard to push that wall over. It's a sturdy structure. I love that analogy. I stole that from one of my friends in the industry. […]Chris Gwyn (06:20)Can you tell us in particular, about some of the health or immune outcomes? You had mentioned immunity that you saw in a study, and what also excited you about to look in the future?Dr. Stephanie HansenThis was an eight-week trial. Basically, what we did was we had a pen-based study, so Delivering to Pens. That's what we call an experimental unit for this. This was a set of steers that came out of a ranch up in Wyoming, I think, for this. Basically, we tracked weekly feed intakes throughout those eight weeks of the trial. As expected, intakes are pretty low when cattle first arrive, and they're newly weaned, they're bawling, so they're just literally figuring out everything in life. And slowly, intakes increase over the eight weeks. And one of the things, one of our treatments was a ruminal-protected B-vitamin A combination. […]Chris Gwyn (08:50)Was there any direct impact on immunity that you were able to measure in this study?Dr. Stephanie HansenI think one of the things that's been really fun about some of the research that we've done at Iowa State over the last several years is some of the collaborations that we formed. […]Jodi McGill is our collaborator at our vet school. She's a bovine immunologist, and her expertise is really about things that happen in the lung, in particular. She's really interested in bovine respiratory disease complex, which is very common in receiving cattle. With Jodi, what we have done is what I would call a two-prong approach. One is we're actually able to take essentially a tube and put it in that calf's nose, flush his lungs with a little bit of saline, and then draw that saline back up. […]That fluid that we pull back up, they then isolate cells out of there. Some of these cells are going to be things like immune cells, and they're not in the lung tissue itself. They're hanging out around it. This is a snapshot of who's on the way to the lung from an immune response perspective. […]Chris Gwyn (12:42)Are there other interesting key findings from that study that you're able to share at this point?Dr. Stephanie HansenI think the health stuff is really the most interesting. Maybe at the end of the day, 28 days look like it might be the peak beneficial window. I think that makes sense because after 28 days, we're starting to pick up nicely on intakes. Really, the majority of our health benefits are seen there, especially, I would say, in week two and three, which fits perfectly when we typically see shipping fever break and things like that for newly arrived calves. […]