They are desert animals so mine may jut be weirdos to not be cold and to be so wooly. The largest we had was 14.2 and my tiniest right now is 28". The large standard passed away last year so now all we have is 1 standard, about 50" or so and 5 minis. They get grass hay twice per day, about 15% of estimated body weight and all of the straw they will eat. We literally just throw a bale in the pen and add another when that one is almost gone. Norm is penned with Snow and Smokey, pony sized mules, so I don't know exactly how much straw he is eating since the mules help him a lot. The three of them do in a regular 2 string bale of straw in 10-14 days. They stomp a lot of it and love to role in it but it is pretty cheap so I don't really mind. They get salt and minerals but no other feed. This is not normal. They should not be any more sensitive on the back than any other equine. I don't know how hard you are touching but they might flinch away from a little more than firm touch. I've seen folks do the flinch test and rub hard on either side of the spine or tap/push at intervals along the spine. They always get flinches if they do it like this. There is a method to these sorts of "tests" and, if you do it wrong, you will get wrong results.