But just before that the article says:

"Pre-partum nutrition is really important, because the cow sets up the calf's ability to marble," Fluharty says.

Comparing the above link article to what I am doing now, my calves are weaned around 205 days, I keep them on hay only for about 30 days, then open up a cornfield. As of right now in mid Feb I am not going to put out any more hay for them. Just water, mineral and standing corn.

They are looking fairly marbled then at about 400 days and 1000-1100 lb when harvested. I do however see a significant difference between steers in this system. I hope to select/cull to reduce this difference.

It is interesting to read the section about forage putting on more backfat than marbling fat. That jives with my recent experience. My cows and retained heifers are now on good forage and hay only while the steers spend about 120 of their 400 days grazing corn. 

I want backfat on heifers/cows but more marbling than backfat in their steers. Not asking much...

I find the Hereford EPD's for low backfat and high marbling useful too as there is definitely a genetic component to marbling.

Interesting question.

Jim at Dawn