Hi Mustapha,

You can find the nutritional characteristics for these two species in the following site:

http://www.feedipedia.org/

This site is jointly sponsored by FAO, INRA and CIRAD.  It has nutritional details for many types of animal feed (for different regions of the world).  Links for sorghum and Millet are given below.  Check exactly what you need, because for one species nutritional information are given for: grain, whole plant fodder, straw (crop residue after grain harvest) and hulls.

Sorghum bicolour:

http://www.feedipedia.org/node/379

Finger millet (Eleusine coracana)

http://www.feedipedia.org/node/721

For other type of Millet (e.g pearl millet)

http://www.feedipedia.org/search/node/millet

Hope this helps.

-SJ

You can also clear your all doubts from National Institute of Nutrition, Hyderabad, India. There is a guide book for nutritional composition of cereal and millet.