Good that you have an analysis on your hay. Now you know what you need to supplement. What are those cubes costing you?
We have learned that alfalfa hay as a SUPPLEMENT is much cheaper than buying cake, lick tubs, etc. If you could feed 5# alfalfa hay every other day, 25% protein alfalfa, 10% moisture, would give you 2.25# dry matter. At 25% protein they would be getting .56# protein.
You could feed 10# alfalfa every third day if that works better for you. Your cows @30# day of your grass hay, are getting 26# as fed.
6.5% protein would give them 1.7# protein which is right at requirement until third trimester. 54% TDN gives them 14# energy.
So they are short on energy, but using alfalfa hay @2.5# p/h/da @60% TDN would give you 1.5# energy so that would be a total of
15.5# energy. What is the TDN in your cubes? It would be helpful to compare the cost of the two, alfalfa vs cubes and the nutrition
from each. 28% protein sounds good til you break it down to how much protein they are getting out of 1.5# of cubes. Protein that high tells me that some of it comes from urea. A little urea is okay but you don't want to much because it causes other problems....cows can't digest it so it takes a lot of energy for her to break it down to utilize it. What is the protein source in those cubes and what is the energy source? Can you post a tag?
Your comment about what happens when there is green grass showing, we found that putting out an old bale of anything....just set it out there--the cows won't eat it like they would when on full feed, but they'll come by and work on it and soon it is gone. Cows chase dry matter in the spring, not green grass--the green grass has everything they need, but it is high % moisture. We are finding out more all the time how important dry matter is. Putting out those old bales seems to make cattle more content and they will breed up better. We laughed when we were told this and we said 'they aren't going to eat that old junk stuff." We were wrong. We tried it and it sure does work.
You are right on, with your energy statement. In our country, protein is easily met, energy is what is lacking. I think you can get more energy in cows with something less expensive than cubes. But it depends on what the cubes are costing you.
This is an interesting thread.
I commend you for wanting to take care of your cows!
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