I wanted to WARN anyone using the chicken nipples with baby chicks----watch out that you aren't forming a vacuum! I almost killed my chicks.
We started them off on the nipples right away, I have 4 chicks, so I took two water bottles and put a nipple in the bottom of each, screwed on the top, and hung them in the brooder. I tested them, and water was coming out. I showed each chick how to get water when I brought them home from the feed store, and they all seemed to get it right away. I watched on and off that first day, and all seemed good. The next morning I was surprised how little they drank. I could barely see that the water had decreased. I got a spoon and tried to put some water on it from the nipple, and could barely get a drop or two. Turns out, with the tops screwed on tightly, a vacuum forms in the water bottle so no water will come out. (I thought air bubbles would go in through the nipples, but it doesn't) The chicks were desperate for water. After several hours panicking, feeding them all diluted pedialyte with a dropper, and drilling an air hole in the top of the water bottle the chicks seem to be behaving normally today, scratching around and running into each other. And they drank more like what I would think, maybe a cup of water.
So, anyway, either do NOT screw the top tightly on the water bottle, or drill an air hole in the top. Nipples do not let in air.
(This is not usually a problem for grown chicken waterers, as they aren't a sealed container.)