Just back online after a holiday.
Firstly, Jerseys can be tricky to get in calf using AI. I struggled a lot at first but
have got better at it now. The main thing is to make sure they don't get upset *at all* for a good 6 weeks after insemination - and any change can upset a Jersey, they like routine.
Secondly, we have a superb Angus bull (and I'll tell you what his Jersey x calves are like in about 5 months' time
) - but he was subfertile when we bought him - from one of the top local Angus breeders - at 14 months old. We had the vet at him, of course, and there was nothing wrong with him at all, he was just immature. (He was acting the part but firing blanks. Sperm count *extremely* low. He's fine now
) So I would say you absolutely cannot bank on a youngster doing the job, no - and you would definitely need to know that the girls were in calf before you sent him away.
I haven't tried Hereford on mine but Herefords are used on dairy heifers to give them an easy first calving, so it could be a good one to use. Jerseys have a very wide pelvis so really shouldn't have a problem with a Hereford calf. (Although I do use AI for a Jersey calf for mine first time, and would use the Angus if I couldn't get them with AI.)
As to disease status, ask your vet. Up here ours recommends BVD-free for *at least* two years. You'll have other advice locally, they'll know what's what in your area.
And it's disease status that is the worry with hiring bulls, of course.
I suppose you've already checked what live bulls are around on the farms near you? When we were struggling to get Hillie in calf for her 2nd, and our bull wasn't yet working, we had lined up that we could walk her along the road to the neighbour's Whitebred Shorthorn if we needed to...