Raspberry protection

I found that summer raspberries were much more attractive to birds than autumn ones, which are usually left alone, at least where I am.

If you do net (and unless you construct a large fruit cage it's a bit of a nuisance TBH) it should go down to the ground and be pegged there or you run the risk of trapping birds inside it. Upturned small plastic bottles or small drinks cans make good cane-toppers, and the netting (which should be of large enough mesh size to let bees through) needs to be in place as soon as the berries start to ripen.

Raspberries need plenty of water, and should be fed if you haven't done so already - mulching helps keep the roots cool and moist.

I daresay the chicken manure would make both a good mulch and feed (unless you mean the dried poo variety which is a good feed but not a mulch!)

Don't know much about using comfrey as a mulch - it would no doubt help keep the moisture in (almost anything would!) but you need a comfrey expert to advise whether it's a good way of feeding too (my guess is that it would be a long time before it released much in the way of nutrients.)

I think Jay may have meant that the dried pellets don't make a good mulch 

The stuff from the bottom of the sty would be fine, I would think, especially if you wet it as it goes down