Spent Grain and yeast for my ducks and muscovy

I have access to a nearly endless supply of tons of spent grain and gallons of 'dumped yeast' from my brewer husband. I have read quite a bit about feeding it to pigs and chickens, but I need to figure out how to best use it for my egg ducks and muscovy.

I have tried offering it to them as a separate  free feed supplement, I've mixed in with flock pellets, and I've mixed it with corn. The corn seemed to go the best, oddly they ate a greater portion of the spent grain than the 20% mix I intended because they usually leave some corn in the feeder. I worry about this since I'm trying to raise them efficiently for meat. The birds free range in their paddocks 24/7 so they do have good access to supplemental forage. They look healthy but I have seen them fatter.

some of my limitations:
harsh climate, this year to date ranged from -10 to 110F
cash poor

opportunities:
I have a few acre pasture, some of it has been divided into a shift paddock system for the ducks but there is a ton to work with.
lots of extra eggs
access to poultry offal in large quantity



some ideas that we have bounced around were

pile/compost style feeding like chickens
meal worms
bsf
red worms
making flock blocks (maybe they'd like that more?)
trying other protein/carb additions
some sort of silage/fermenting thing
feed to fish or some aquatic thing and then feed them to the ducks?


What ideas do you have or what have you observed? What other animals could I incorporate to use up the grain?

Fermenting might be a great idea to decrease feed costs. I use Scratch and Peck feeds, and they have a lot of information about how to ferment feed (https://www.scratchandpeck.com/feed-and-fines-maximizing-the-value-with-fermented-feed/ and https://www.scratchandpeck.com/wp-content/uploads/Fermenting-Feed_7-27-2015.pdf. Here's a study on it increasing protein content and reducing feed usage https://www.ncbi.nlm.nih.gov/pubmed/19373724). You basically let grains sit in water (container should be about 1/3rd feed, 2/3 water with some air space at the top because the grains will EXPAND) with a cloth over it for three days. You can also jump-start the fermenting with some lacto-fermented saurcraut or pickles (but not yeast) or the liquid from your last jar, so it only takes a day to ferment. I would definitely try fermenting your feed if you can, as it did seem to help my ducks a lot when I did it. I will note that when it gets hot, that stuff can grow a kahm yeast which is harmless but does smell peculiar (kind of cheesy, but was totally unbearable when I was pregnant).

If you do try the composting thing, make sure to read up on all the things that are toxic to ducks. Also, mallard ducks don't seem to be able to rip up compost like chickens, though perhaps your muscovies can? With my ducks, I had to chop everything up for them...or just be okay with them mostly munching on the flies that bred there. Also, be aware that you might end up with a rodent problem .

I wish I knew what other animals could eat your spent grain--that sounds like a great resource!

In the heat I'm finding I need to use up the grain within a few days. In the winter is seems to slow ferment indefinitely. If it sits in poor conditions it will grow mold and stinky ecoli bacteria. VERY bad for fowl. iWhen I add things like scratch  or corn to the spent grains they get up fermenting quickly. The trick is getting the right mix of nutrient, I'm not sure I've figured it out though I do try to calculate it. Im not sure I've really figured out how to quantify the spent grain, there are several variables to it nutritionally (how wet, how efficient the mash was, how much protein was in the grains to begin with.) One cool thing about spent grains is not only are they fermenting, they were presprouted before malting.


So far when it starts to go bad I am adding it to the compost pile, which has been rocking the compost pile, it's awesome. Still, not the best use since I am paying for feed. I'm going to try two new things to try to use up more of it for the ducks directly.

1. I'm going to try using my extra eggs and some scratch grain with the spent grain and yeast to make baked flock blocks that I will freeze. Maybe even if they don't like them I can sell these to chicken people to offset feed. I don't think there are regulations around here about doing that..

2. I'm going to try adding a deep compost pit to each paddock, I think I could use this as an anchor point to help revitalize each paddock while also persevering grain for the ducks. Sort of like for pile chickens, but due to the harsh climate I'kk use the earth insulation, maybe even add some strawbales on it. I'm thinking Ill dig at least 4'x4' square hole 3' deep, adding not moldy grain and then recovering with dirt and mulch. I'll start the next couple paddocks at the same time so we can see if there is an ideal incubation time to break into this for the ducks. I'm interested to see what insect activity it brings at which stage. I do have 3 chickens that follow the duck flock, scratching their caked poop areas. It might make sense to incorporate them directly w/ the compost style feeding.

I feel like some sort of insect farm is a no brainer..but I'm embarrassed to admit how many worm farms I've killed. lol. I can dig you piles of worms from my compost but a worm bin lasts me a couple of months.  

I'm not sure how to quantify if these things are working, I have so many ducks (41) in so many different stages of growth in a mixed flock. I've considered dividing the flock into my "keepers" and those that are being raised for slaughter or are up for sale. I've also considered dividing the muscovy and anconas, though there are some things I like about having them together.  

I like the flock block idea. I'd never heard of them, but it sounds like horse bread.
A well dryed bread would keep well.
Just drying the spent grains would create a long lasting,saleable product.
I'd be hard pressed to use any eggs in such a thing.
If you're game, blatticomposting might work for you.
I think cockroaches would thrive on spent grains.

One more thing. Secondary fermented products.
They won't solve your feed problem, directly,but a small beer,or a malt vinegar could be made from the grains.