New Hay test calculations from vet ??


This is probably unnecessary confusion, but my vet visited today for a recheck on Cody and to draw blood to see if his insulin had come down. I was going over my recent hay test with him and, as expected, he is most interested in the NSC of the hay (the hay test in question is the one I just uploaded in my case history) not the ESC + starch percentage that Dr. Kellon and the group uses. He stated there is a new way of calculating NSC but did not give me the reason or science behind it or who is recommending it. I ran the numbers on a previous hay test and it raised the NSC by around 4%, so fairly significant. Anyone else hear of this calculation for NSC or know why some vets might suggest it's use?

100 - moisture % - crude protein - crude fat - neutral detergent fiber - ash = NSC%

I am still working from the ESC + starch < 10% recommendation as being the benchmark for safe hay (not the NSC%).

Thanks in advance.

Eileen Towner in Western Washington state 2020  .

Sherry Morse

Well it took a bit of searching via Google but I finally found most of that equation on two websites: and

However, it does not include moisture % and is used in relation to cattle feed calculations

NSC content is not measured directly, but is calculated by difference:

NFC = 100 - Crude Protein - Crude Fat - (NDF - NDIP) - Ash

A variation on NSC is Non-Fibre Carbohydrates (NFC), the calculation of which does not deduct Neutral Detergent Insoluble Protein (NDIP) from NDF.