|Full disclosure. This image is of Racing Oxen. How can you tell? Easy, look at their chips. No, actually, that is what the caption of the photo said.
I don't believe I have ever seen cattle with so little gut-fill and so many ribs.
For the non-farmers, cattle have four stomachs. The first stomach is enormous and is called the rumen. The rumen functions as a fermentation vat where microbes break down cellulose and other indigestible carbs and proteins into short-fatty acids and digestible proteins.
The fermentation process is slow, especially for low quality, over-ripe forage. Cattle on a high roughage diet usually have a rounded, beach-ball on legs look to them. For example, a thousand pound steer might have a rumen volume between 10-and-30 gallons.
It is hard to imagine these animals having more than five gallons of rumen fill and I doubt they are getting grain supplements.