In the title you said "Tift", but in the body of your question it says "tight". I assume you mean "Tifton"? If so, that's a type of Bermuda grass, which has relatively small stems and narrow leaves, so it shouldn't look like straw.
As with any hay, the nutritional value will depend on many factors, like the amount of growth when it was cut, and what (if any) fertilizer was applied to the soil.
I don't know anything about peanut hay, or why your cows would prefer it. Maybe the new hay is poor quality, or maybe your cows just aren't accustomed to it, or maybe the peanut hay is just more palatable than the Tifton (if that's what you have).