Millet is actually pretty crappy when it comes to protein lol. Take a look at the fourth and fifth lines of this chart:
http://www.littlefeatheredbuddies.com/i ... seeds1.jpg It tells the total protein in grams (which is actually the total amino acids not the total complete protein - a lot of those AAs are superfluous). And it also gives the amino acid score from SELFNutritionData, which is an indicator of the quality of the protein (meaning the completeness of the amino acids). Millet has only 11 g of protein per 100 g of seed, and the amino acid score is 38 which is the lowest on the page. Sunflower has 21 g of protein and an amino acid score of 88, which is a lot better. It's also considerably higher in calories, so there's a tradeoff. Safflower is lower in calories than sunflower but it's also lower in protein, vitamin E, and B vitamins.
I haven't been able to figure out exactly how their amino acid scoring system works. It's not based on a scale of 1 to 100, because I've seen scores as high as 144 (for beef steak). I don't know exactly how much complete protein is in sunflower, but the amino acids are better than most of the seeds on the chart. I know what the limiting amino acid is too - it's lysine. "Limiting amino acid" means the one that you run out of first when you're putting together complete protein with the amino acids on hand. So if you offer another food that's got some extra lysine in it, it will combine with the AAs in the rest of the diet and help you get more complete protein out of the sunflower. Safflower is even shorter on lysine than sunflower is, so it has an amino acid score of only 65.
Here's the Self Nutrition listing for sunflower:
http://nutritiondata.self.com/facts/nut ... cts/3076/2 I always hit the little dropdown box that lets you change the amount to 100 grams, so when I compare stuff everything is in the same units. It has a little black and purple "protein quality" graph showing you that the lysine is limited but the difference isn't too bad. Further down on the page if you click "more details" under Protein & Amino Acids, it will tell you exactly how much of everything there is.
Here's the listing for millet:
http://nutritiondata.self.com/facts/cer ... sta/5701/2 It's WAY low on the lysine, which is why its amino acid score is so bad.
BTW the essential amino acids for birds aren't exactly the same as the ones for humans. I don't remember offhand what the difference is, but there's one that's essential for humans that isn't essential for birds, and one that's essential for birds that isn't essential for humans.