Definitely not normal. It actually looks like my megacolon rabbits poops. They are irregular shaped like that, and can be really big and really small. It's a genetic thing with one of my rabbits, and digestive damage from getting sick, with another rabbit. It's a possibility that this is the cause with your new bun. If it is, then you are better off never giving treats, and you may even have a hard time giving him pellets, as it will start to cause digestive trouble for him. My one rabbit with genetic megacolon, has a diet of a limited amounts of a specific pellet that doesn't have added sugar and grain in it, unlimited timothy hay, a small amount of alfalfa hay, and a few dark leafy greens. The other rabbit with megacolon from intestinal damage, doesn't get any pellets(as he can't tolerate them without getting sick), unlimited timothy hay, some alfalfa hay, and a handful of dark leafy greens. Neither one ever gets treats with sugars or carbs.
It could also possibly be due to being on new food, but I haven't observed any rabbits having these kind of poops from food problems, besides my megacolon rabbits. Someone mentioned that they had a rabbit with kidney disease, had poops like this. Signs of kidney disease are changes in appetite, increased thirst and urination, severe weight loss. But with him being a new rabbit, it might be hard to determine these things yet. You would need a blood test to know for sure. An upset of the gut flora, may be a possibility as well. You could try pet probiotics, but if you do, try and find one with the added sugar being dextrose or glucose. I think Bene bac has that, if you have it available there. Also, start out with a very tiny amount and keep an eye on the poop, and only gradually increase if there aren't any poop changes, like all of the poop coming out really tiny or mushy, or him sitting hunched up in one position for a long time, or teeth grinding. You want to make sure he is drinking too. It could be that he is a little dehydrated if he isn't drinking, or if he isn't getting enough greens to make up for him not drinking(if he isn't), and that could contribute to the strange poop.
It would probably be best to wait a while on sugary/starchy treats, and on the pellets, to see if his poop changes back to normal, after he has been with you a little while and starts to eat a bunch of hay. If he starts to have normal poop, then you should be fine to gradually start him on pellets. If the poops stay the same, you could still try pellets if you want, but you will want to wait til he is eating a lot of hay, and you will want to go really slow with it, like starting out with 3 little pellets, twice a day, for a few days, then very very gradually increase the amount each day. With one of my megacolon buns, I did this, and after about a month, I was up to 1/16 cup, twice a day, until I noticed he was starting to squint and sit like he was uncomfortable after eating pellets. So I stopped pellets for him, and he was fine after that. This is what one of my megacolon buns poops looks like.
