Thank you Bonnie for your reply, 

The hay was initially soaked because we didn't know S/S numbers, the owner noticed Plutón's energy went down but we didn't change anything.
Then the hay was analyzed (results in the CH) and because it was under 10% we decided not to soak because it was extra work for the barn and extra expense to pay for the extra water to the facility manager.

What happened was that Plutón became sad and sore in his front hooves and gained a lot of weight very fast, so I asked the owner for an insulin and glucose test that came high for insulin so we started soaking again. He inmediately got better, he lost weight fast (BSC 5 now) and wasn't sore anymore but is low energy again. He is walking fine without boots but he shows the same low energy he showed the first time the hay was being soaked.

My guess is that he might be getting too little glucose and/or his muscle glycogen is not being replenished as it should, but it is just a theory and wanted to know if it is possible.

One solution that comes to my mind is soaking for 30 min instead of 1 hour or adding a safe concentrate, this one only if he keeps losing weight because I believe he is still losing. Soaking for less time is something I am not totally convinced about because the hay came with low sulfur so nitrates might be playing a roll too in his soreness when the hay is not soaked.

Thanks a lot.
--
María Durán Navarro 
Dec 2017
Madrid (Spain)

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