Don't see why not. But if it worries you why not make a separate heap of it? Its quite OK anyway to use it neat as long as its totally rotted- changed texture, loss of smell etc. After a year in any case there shouldn't be a problem.
My Mum used to send me out with a shovel and put what I collected straight on the roses and nothing drastic happened.

If you are mostly fill ing your compost bin with horse 'poo' I think you need to dilute down with things like card and green stuff. Keep collecting the 'poo' and create a heap of somewhere to allow it to totally rot down, a good year of time! You can put the just collected neat 'poo' around roses and similar but keep away from the actual rose and only a shovel full of. You could also dig trenches where your tatties are to grow and add the 'poo'. Don't overdo on anything though.

Thanks, i like the idea of digging it in where I’ll be growing potatoes. From the road straight into the spud trench - yes, no problem.

There you go Hank :)

Agree with Mg. If it's totally rotted down like she said, it's high quality top soil.