Potential of farm-produced crop residues as protein sources for small-medium yielding dairy cows

Abstract

The nutritive value of fifteen crops and by-products were investigated in terms of the protein and energy value for 
rumen microbial protein synthesis using in-situ and mobile bag techniques. The sunflower feedstuffs and the cotton 
seed cake have low digested carbohydrates, which may limit optimum microbial protein synthesis, while forage 
legumes and cereals have higher digested carbo-hydrates (P< 0.05). Thus, one way of improving protein digestibility 
protein rich crops is to feed them with cereal crops. The cereal grains (maize, sorghum and pearl millet) and the 
forage legumes (groundnut and cowpea tops) showed a negative protein balance value, suggesting that nitrogen 
limited optimum microbial protein synthesis in relation to the available carbohydrates (P< 0.05). The nitrogen (N) 
content of the ram press sunflower cake (43 g/kg DM) was within the range of the N content found in the commercial 
dairy concentrates (32 - 57 g/kg DM). However, the N in the sunflower was more degradable in the rumen (92%) than 
that in the commercial dairy concentrate (P < 0.05). It can therefore, be concluded that the ram press sunflower cake 
is potential source of N for small-medium yielding dairy cows.