I really love having roosters, 100AcreWood, but I don't have guinea hens, so I can't answer that part of your question. While it is definitely not necessary to have a rooster, they do help protect the flock, and I love watching their antics and how they interact with the hens. You'll want to have enough hens that the rooster doesn't over-mate them. I also like having fertile eggs so I can hatch them.
As far as the feed goes, if your pullets are all the same age, I start the layer feed when the first one starts laying. I mix flock raiser and layer feed 50-50 year-round, plus leave out oyster shell free-choice. The reason I mix them is to give a higher protein content. Your leghorn will definitely want the oyster shell. They are egg-laying machines.
As far as the feed goes, if your pullets are all the same age, I start the layer feed when the first one starts laying. I mix flock raiser and layer feed 50-50 year-round, plus leave out oyster shell free-choice. The reason I mix them is to give a higher protein content. Your leghorn will definitely want the oyster shell. They are egg-laying machines.