Does rice milk or milk from grain-fed cows emit less methane?

[FlatAssembler]

So, a few days ago, I made a new video about vegetarianism. I won't link to it, as that seems to be against the rules. In the video, I mentioned the methane argument for vegetarianism. However, does anybody here know for sure, does rice milk actually emit less methane than cow's milk? Has there been some actual study about that? I know some studies that show oat milk emits less methane than cow's milk, but I know no such studies about rice milk. I know the production of rice emits some methane, so I think it's a reasonable question whether rice milk or milk from grain-fed cows (that most milk comes from today, which also emits far less methane than milk from grass-fed cows) emits less methane.