A three year old should be able to cover 25 to 30 cows easily. Make sure he has a breed soundness exam (BSE), though, because if he's not fit - he may not be able to successfully breed one.
A strong 3 year old bull can service 30 cows easily if you turn him in to freshen all together. If you leave him in year round, he can service 50-60 with no problem, unless you live in an area where they are in a 200 acre or bigger pasture
As an Amazon Associate we earn from qualifying purchases. Product prices and availability are accurate as of the date/time indicated and are subject to change.
Unless you have alot of pasture and feed for them it's hardly worth the time and expense to keep a bull for such a small amount of cows. Maybe you can get your cows bred and then loan him out to a friend or neighbor who could put him to use on a larger herd for awhile. That's just a thought.