The Southern railroads were so terribly overloaded with the need to transport troops, war material, and agricultural products that could not be produced elsewhere (ie salt, sugar and molasses) that carrying cattle long distances could never happen. Therefore, cattle had to be carried by water (steamboats down the Red and Ouachita Rivers to Vicksburg) and used within a couple of hundred miles of Vicksburg or by swimming the Mississippi River and walking two or three hundred miles. Obviously, Atlanta, Charleston and Richmond will have to be supplied by closer sources than Texas. In fact, the diffused cattle production in the rest of the Confederacy provided beef enough for the first year or two. After that, the easy/close cattle had been consumed and the reliance on pork, in the east, was the only solution.
The cattle from Florida dream turned out to be the product of real estate developers and their sales programs. The cattle were over counted, were too far apart to easily collect, and needed too many potential soldiers to collect them. When collected and driven north, the nature of the country and the weather prevented the arrival of large numbers of healthy cattle. The cattle that did arrive was consumed in the Atlanta/Charleston/Montgomery area.