Q.horse manure
Can you plant vegetable directly into aged horse manuure. I say no and my husband says yes.

Properly composted, horse manure is an excellent source of fertilizer or amendment to the soil.
The composted manure alone is likely to rich in nitrogen for a vegetable garden. You may have lots of green leaves, but no vegetables.
You need a good balance in the soil.
Here are some articles for you with more information.
https://www.gardeningknowhow.com/composting/manures/horse-manure-compost.htm
https://www.gardeningknowhow.com/composting/manures/the-benefits-of-manure-in-your-garden.htm
https://www.gardeningknowhow.com/edible/vegetables/vgen/vegetable-garden-soil.htm