- cU i
FLORIDA AGRICULTURAL EXPERIMENT STATIONS
Dairy Science Mimeo Report DY65-5
December 21, 1965
CANE MOLASSES FOR DAIRY CATTLE
R. J. Martin, Jr.1,2 and J. M. Wing2
Cane molasses is an important feed for ruminants. It is a source of highly .
available energy and can be used to stimulate consumption of poor quality
roughage and unpalatable concentrates. About 40,000,000 gallons are produced
annually in Florida. At certain times of the year cane molasses becomes
available to farmers at a very low cost. During this time it would be well to
feed as much as possible. The effects of the level of molasses in the ration
then become important.
Other research has shown that methods of feeding alter the effects of molasses
in the diet. Modern practices call for high concentrate rations for dairy cows.
The optimal level of molasses to feed in high concentrate rations has not been
determined, and thus the following experiment seemed desirable.
Rations containing 0, 6, 12, and 187 cane molasses were fed to the limit of
appetite twice daily to four rumen-fistulated steers. The composition of the
rations appears in Table 1. Digestibilities of dry matter, cellulose, and
energy were depressed when molasses was added to the ration. However, no
additional depression was observed as the level of molasses increased from 6
Composition of experimental rations
Treatment 1 2 3 4
0% molasses 6% molasses 12% molasses 18% molasses
(lb) (lb) (lb) (lb)
Corn 35.0 30.0 25.0 20.0
Brewers grains 10.0 10.0 10.0 10.0
Cottonseed meal 20.0 20.8 21.6 22.4
Wheat bran 5.0 5.0 5.0 5.0
Molasses -- 4.2 8.4 12.6
Alfalfa haya. 30.0 30.0 30.0 30.0
a. Hay was chopped and mixed into the concentrate ration.
I1 Present address: Dept. of Animal Husbandry, University of California, Davis.
2. Research Assistant and Associate Dairy Husbandman, respectively.
The average digestibilities for the different ration components are shown in
Table 2. Crude protein digestibility was essentially the same for all the
Summary of digestibility of nutrients and digestible energy
Treatment Protein Dry matter Cellulose Digestible energy
Control 74.92a 75.21a 68.428 75.41a
6% molasses 73.45a 68.06b 61.58b 67.93b
12% molasses 72.91a 69.17b 57.81b 69.01b
18% molasses 72.47a 68.66b 60.15b 68.52b
Values with different superscripts differ at P<0.01.
A study of the molar proportions of volatile fatty acids (VFA) revealed no
change in the production of acetic, propionic, butyric and valeric acids
(Table 3). The molar proportions of isovaleric acid were lower in the rations
containing molasses. Since isovaleric acid made up only 2.72% of the total
VFA produced in the rumen, the importance of this depression is questionable.
Rumen pH and the acetic-propionic acid ratio were unaltered by the treatments
Summary of molar proportions of volatile fatty acids and pH of the rumen contents
Treatment Acetic Propionic Butyric Isovaleric Valeric Acetic/ pH
Control 62.21a 20.67a 12.74a 2.72a 1.54a 2.94a 6.54a
6% molasses 63.53a 19.55a 12.76a 2.58b 1.58a 3.27a 6.62a
12% molasses 62.72a 19.86a 13.11a 2.27b 1.62a 3.08a 6.61a
18% molasses 63.91a 19.42a 13.18a 2.38b 1.67a 3.38a 6.65a
Values with different superscripts differ at P<0.05.
Cane molasses levels up to 18% of the concentrate ration have been shown to
alter the utilization of the ration by ruminants. However, the production of
VFA was not changed by the addition of molasses. The acetate-propionate ratio
in the rumen contents of the animals on the molasses rations was adequate for
normal milk fat synthesis.
Additional work with lactating cows will be necessary before definite recom-
mendations can be made because molasses has been shown to alter utilization
of some ration components. It seems logical, however, that molasses can make
up as much as 18% of the concentrate ration without seriously altering rumen
The authors wish to thank the U. S. Sugar Corporation for partial support of
this work, and the following of their colleagues for assistance: Drs. J. E.
Moore, C. J. Wilcox, and F. C. Neal.