Pellets are usually made in a machine that uses hydraulic pressure to compress them so they will stay together. So it's not a simple DIY project, I would think.

Curious why you need pellets - are you wanting to store it for an extended period, or... ???

thanks
I suppose when you put it like that I could just lay it(my semi-rotted manure) on as a mulch.
I think it is the fact that I have run out of the pellets and it is a long drive to get them again that set me to wondering along those lines..... I was also interested as to how they were made .

Manure should not be put onto a garden as mulch because too much of the nutrient value is lost to the atmosphere and if it is put down during the growing season the potential of getting disease pathogens on the foods growing there is much too great. Compost that manuure, with 3 parts vegetative waste, and if the material gets hot enough that should kill off any potential disease pathogens.

thanks
yes I understand.

However I am pretty unprofessional as regards my stable manure and ,unless I give my donkeys plenty of straw, the heap doesn't heat up as well as it might otherwise.

Can I hope , though , that if I collect and use the end product after a long enough period that the pathogens will have died out?
I mean after a year?
I don't expect the weed seeds to have died but can I be hopeful regarding pathogens provided the heap has rotted enough?

Yes, if it's been aerobically composted (i.e. with plenty of air, not a smelly anaerobic pile) it should be free of pathogens after a year. Quite possibly well before that.

well the way I do my heap is normally to just fork it out from the stable onto an area just outside.I might not aerate it as such , other that moving it around once or twice to accommodate additional amounts every so often.

I think the result is a mixture of aerobic and anaerobic (although I do tend to use the best stuff first which would be at the top or at the edges and I do cover it with a carpet so it doesn't get waterlogged.)
If the stuff that has decomposed eventually anaerobically isn't smelly or slimy would it be reasonable to hope that it to might be more or less free of pathogens at that stage?

If it's turned over once or twice during the process I wouldn't worry about it.

Some disease pathogens most likely die quickly while others are like many of the plant disease pathogens and can hibernate, go dormant, so to speak, and reappear the next growing season. Like the Tetanus Toxoid that can stay dormant in the soil for years before finding a point of entry into you and developing from there.