Is my SO taking advantage of me?

We moved in together about 9 months ago. We both have pets, his is a dog. Since we've been living together I've progressively felt as if I'm responsible for his dog. We have different sleep schedules. This is relevant because since we've lived together, I've been the one to take the dog out first in the morning. My SO claims the dog doesn't want to go out as early as my SO get up. (even though that was his schedule before we lived together). The dog eats twice a day. He does not put out his morning food. The dog is picky about eating, and won't just eat whenever he needs someone there with him, he's gotten better about it now though. It's been ongoing thing where I'm keeping better track and keeping thee dog on schedule of eating with us and having fresh water. I've discussed my frustration, and it's been discussed that I'm goin to take a step back from responsibilities when he's home. Still he forgets at times.

Today I mentioned the dog was low on water, the second time being more intently. He fills up his water jokingly. Then later he's in bed and I reminded him that he hadn't fed the dog. He said "I was going to" I said " doesn't sound that way with you trying to get me to lay down with you" (He goes to sleep earlier than me, but tonight was extra early.) then he changed it to he had already fed him. Which I knew he hadn't, so I told him that. I then asked him if this was why the dog weighed 15lbs less when I met him. He laughed and said no and that he would feed him. I left the room to finish what I'm doing, go back shortly after, and he is passed out. Something else to mention is my SO is a drinker. I know that can make you forgetful, but responsibilities should come first. Do I sound like a jerk? Do you think he's doing this intentionally knowing I'll pick up his slack? There's a lot more details I couldn't fit, so if you have any questions, I can answer them. Thanks in advance!

Is my SO taking advantage of me?
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