1850's Four Poster Bed

I recently acquired some items of interest from my mother's estate.......this bed has been in our family's possession since the 70's when we moved into a century home in Ontario, Canada. My father and I discovered this bed in a barn on the property (see photo....small barn - that is still erect on the property). I do not remember if it was already painted at the time, but it is painted white now. I am sure that we used this bed throughout my teens, but it didn't mean a thing to me then :)
Now.....another story.....I am fascinated by this 'stuff'. I stripped two small areas on the inside of the baseboard and found 'reddish' wood on the post and a 'coarser, lighter wood on the crosswise plank'. Overall, the bed is in good shape - a few small cracks, but no chips, etc. I think it was a 'rope' bed at one time as it has a couple of small holes in the railings and a 'slit' (my apologies for my terminology). Now is has two square 'bolts' that fit into a metal slot in the baseboard. The size of the bed, from the metal slots across, is 39"W and the 'railings' are 71"L.
I also have the slats. I have included a photo from an Upper Canada Village book - as it is somewhat similar to that.
Can anyone tell me how old they think the bed is. Do you think it could be mahogany......would mahagany look different with different cuts?
Do you think it originally was a 'rope' bed and then was updated?
Thank you to all of you who take an interest. As you can see, I am from Canada, and you know, our history isn't as old as most countries....but is certainly can be fascinating.