Cell to Rail: Pre and Post Natal Development

yeah you made a very interesting presentation back this spring when we did the hoof to plate conference there on campus and it's something i'd really not thought about i've thought about it in other aspects but so we went back through it you shared your slideshow with us and so we thought we'd share this with producers i'm going to kind of kick it off this is about development and developing the beef animal and where all that starts and so It starts prenatal and postnatal.

We get is how we grow the beef animal to try to get the best beef that we can.

So with that, why don't you just kind of explain to us, you know, in a short, you know, you had a nice hour long presentation.

We're going to try to shrink it.

How skeletal muscle and fat development occurs, both prenatal and postnatal.

Yeah, and it's such a good question.

And I think often, like as a meat scientist, one of the questions that I kept getting and why I really started diving into this a bit more is people would see a carcass and would want to know what went wrong.

Why wasn't it yielding? Why didn't it grade? And really didn't understand how the components of meat, muscle and fat, were developing when they were developing and what contributed to their development.

And I remember in graduate school and even as an undergrad student taking classes on growth and development, really focusing on muscle development, skeletal and fat development, but never really tied that together and made the connection with, well, how the animal develops both pre and postnatally is connected to the ability of that animal to produce either a high yielding or a high quality green carcass.

And so we really started taking a step back when I was interacting with producers across the country and especially post, like in the pandemic, when folks were really getting interested into home-raised beef, particularly other species, but really in the beef space and understanding why.

why despite their best efforts, things weren't working out as they planned, right? Like we thought we did everything right.

And then at the end, it didn't work out as we thought.

So that really was what led to this sort of discussion series that we've been having with producers across the country is understanding the building blocks of meat, primarily muscle and fat, but the skeleton plays a role because when we talk about meat, we're talking about skeletal muscle.

So I like to say that the skeleton is the foundation of the house that we're building.

And skeletal muscle development begins in the prenatal period.

So while the animal is in utero, most of the cells that will form their skeleton are developed.

And then after birth, just like within humans, those skeletal cells start to mature and differentiate and bones start to get longer and start to get more dense, etc., Muscle development is very similar.

It occurs a little later in the prenatal period, but at the time of birth in humans and in cattle, we have a fixed number of muscle cells, meaning that the number of muscle cells we will ever have is determined at the point of birth.

Now, there's some wiggle room with satellite cells and some of these things, but it's pretty small and on the margins.

So what that means from a human development perspective is that I can't today take pills and get more muscle cells.

All that I can do is grow and size the existing muscle cells that I have.

What that means from an animal production perspective is that the ability of an animal to produce muscle depends on what happens to the mother or the calf in utero.

And at the point of birth, all that changes is the ability of that muscle of that animal to grow the muscle cells that it already has.

Fat is the one that's a little different in that fat kind of transcends the prenatal and into the early postnatal period.

And it reflects how the animal uses fat.