Sugar in Dairy Rations

Until more is clarified, we suggest a target of 6% sugar from all sources.

Here’s Why -- It is known that sugars increase rumen fermentation rate and improve rumen utilization of soluble protein. In the CNCPS model, all the carbohydrates in molasses are assigned to the A category - Sugars - and given a 500% per hour fermentation rate.

A number of studies have shown that cows, particularly cows in transition and early lactation, benefit from molasses or sugar sources in the diet. This is from an abstract presented at the 2001 joint ASAS/ADSA annual meetings by Dr. Glen Broderick of the USDA Forage Research Farm in Prarie du Sac, WI.

Molasses, %	0	4	8	12
HMSC, %	29	25	21	17
DM1, lb/d	55.3	56.9	57.8	57.3
Milk/DMI	1.51	1.46	1.48	1.43
3.5% FCM, lb/d	91.3	92.6	95.7	87.1
Fat, %	4.07	4.26	4.11	4.06
Protein, %	3.12	3.09	3.11	3.04
%Sugar, total ration	2.6	4.2	5.6	7.2

Molasses was substituted for high moisture corn in a diet composed of 40% alfalfa silage, 20% corn silage, 8% soybean meal, 2% fat, 1% vit/min supplement, and the remaining 29% was divided between high moisture corn and varying levels of molasses. Replacing up to 8% of the high moisture corn with molasses for a total diet sugar level of 5.8% resulted in the maximum DMI and FCM.

It is important to assay. Sugar content varies greatly. Here are some recent sugar analyses from Mary Beth Hall of Florida:

Ingredient	Alfalfa Hay	Alfalfa Silg.	Corn Grain	Corn Silg.
% Sugar	5.8 – 12.1	1.1 – 7.7	0 – 5.2	0.3 – 4.6

Bottom line: Test feeds for sugar content. Until we have more information, we suggest doing as Charlie Sniffen of the Miner Institute recently said “Silages this year are lower in residual sugar. Formulate to make sure the total ration sugar is 5 to 7% DM. This will mean adding 2 to 4% sugar to the ration.”