Not if you're not prepared to pay for or pump out extra water for them. You will have to expect your cattle to be drinking more water than normal if you are going to be feeding them this stuff, as it would contain more salt than "normal" hay like Brome or Fescue hay. I believe that this hay is a bit coarser than most, so you will have to watch their body condition and how much and how often they are eating it to see how they're doing and whether it is good for them or not.
No
Grass, and hay, primarily. They are genetically selected to rely solely on grass and hay and not grain.
Hay (dried grass)
Yes, if you are referring to lespedeza-grass mix to use for hay and not lespedeza grass, which doesn't exist. This mix is best for cattle, but not horses as the protein content would be too rich for horses to eat.
cows eat grain, grass and hay
Watusi's eat grass, just like other breeds of cattle do.
Yes. Roughage is in reference to such forage as hay or stockpiled grass.
No beef cattle can also be fed, grass, corn, insilage, silage, grain, oats, barley.
A balanced diet of mainly hay with supplemental grain is better. A sedentary horse fed a good quality hay may not require grain but will benefit from the addition of free choice salt and mineral supplements.
If she was given a choice, she would eat grass over hay. But she likes to nibble on a bit of hay too. Hay is just dried grass, and is recommended to be fed to cattle if they are put in a alfalfa pasture or on a pasture with young, high-nutrient grass to help with digestion and to discourage bloat.
Hay is used to feed animals when grass is not available.
For the rest of its life, as long as it's given water and salt as well. Horses are naturally made to live on grass and hay, and will have no problem living on it for all their lives.