Looking for an accurate nutrition database
You should generally trust the USDA. They've put a lot of effort into getting everything accurately measured for nutrition labeling, and in the US at least, pretty much everyone gets their nutrition data from them.

That's true in this case: the bodybuilding.com nutrition page says "This database contains data from the U.S. Department of Agriculture, Agricultural Research Service." So there's no good reason they should disagree with the USDA - if they do, I'd assume it's because their data is out of date, or they miscopied it from the USDA database.

That said, the differences are pretty tiny (pretty much insignificant in this case), so assuming they haven't made any big mistakes, you should be fine using either - it's supposed to be the same data. (Personally, I would much prefer the USDA's website or http://nutritiondata.self.com/ because they're a lot easier to read than that bodybuilding site.)