Thats the great thing
But what is difference between barley and oats?
Barley Grain
Barley Grain is a filler, like corn, but having higher protein values. Its often used where its abundant for that purpose (or the products of barley, like spent brewer's grains). Unfortunately, Barley contains some chemicals which are difficult for most creatures to digest, and can contribute to reduced weight gain in growing birds as well as sticky fecals in birds of all ages - it shouldn't exceed 20% of total diet in a complete feed, 10% is a better figure if enzymes aren't added to aid digestion. Whole, its very resistant to spoilage, but also almost entirely undigestible - its usually steam rolled or flaked.
Oats (de-hulled)
Another corn-like filler, with the hulls removed (or naked), its more protein dense than barley, still with the hulls, its less (but still better than corn). Its also higher fat, which may or may not be a positive depending on the rest of your feed mix, and may be higher or lower fiber (based on the presence of the hulls). Again, this is used as a filler where its readily available. Like Barley, Oats contain some polysaccharides which contribute to sticky fecals, quantity in the feed should be limited.
Now, comparing the two - Due to the digestibility of their starches and higher fat content, Oats have a higher total energy value, meaning birds need to eat less to meet their caloric needs. You can compare relative differences in average fat, protein, fiber above or in the chart I linked earlier. While there is wide variability based on location, time of year, cultivar, etc, differences in the grounds where these crops are raised generally results in barley containing more Potassium, Copper, and Iron, while Oats tend to be higher in Manganese. They have similar amino acid profiles per pound fed, with oats being slightly superior across the board in terms of the four we most focus on - Methionine, Lysine, Threonine, and Tryptophan.
Haven't located a reputable source yet to compare vitamin content of various feeds, but grains tend to be very high in B-vitamins, and a good source of selenium too. Which is better? Couldn't tell you. (yet)
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