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1.2 Importance of Maize and Rice on Livestock Feed
in Tanzania
In Tanzania, as in other countries in East and Southern Africa, 50% of the smallholder farmers also keep animals (Thornton et al. 2002). Livestock provides milk,
meat, income from sales of highly demanded livestock products to the increasing
urban populations (NEPAD 2005), manure for fertilisation of crops and draught
animal power to ease the drudgery and burden of hand cultivation. Increase in
human population has led to an expansion of cropping land especially in high agricultural potential areas along the high- and lowlands of the country. Available land
for forage production and grazing has become less. Instead, more crop residues,
mainly maize stover and rice straw, are contributing enormously to livestock feed in
the larger part of the year. Due to population growth and land scarcity in Kenya
highlands, for example, smallholder dairy farmers obtain up to 34% of total feed
from crop residues (Romney et al. 2003).
The principal constraint of cereal crop residues as feed for livestock is nutrient
deficiencies for growth, production and reproduction of the animals. Cereal crop
residues have deficient crude protein and minerals and high fibre content. The
digestibility of these residues is therefore low. Efforts to improve the quality of
cereal crop residues include breeding, agronomical practices and utilisation strategies. Vaswani et al. (2016) reported that different varieties of maize fodder differed
substantially in their chemical composition. They found higher concentrations of
minerals and nitrogen content in improved as compared with regular types. In an
assessment of the nutritive value of whole maize stover and its morphological fractions, Li et al. (2004) found that the leaf had the highest nutrients and the stem rind
had the lowest. These workers supported the development of a device that can separate different stover parts so that they can be used more efficiently for different
purposes. Amongst the strategies for utilisation of low-quality cereal crop residues
are urea treatment and supplementation with leguminous multipurpose tree leaves.
The benefit of improving stover and straw quality through improved plant nutrition
is somewhat less reported. Since increased biomass of stover and straw can feed
more animals and leave some portion for soil cover, it is an essential advantage of
improved plant nutrition.
1.3 Addressing Sustainable Intensification of Maize and Rice
Crops as Food and Feed in Tanzania
Intensification in this context means improved efficiency of crop and livestock
production, with reduced greenhouse gas production per unit of crop and livestock
products and more crop and livestock products per unit of water. Neglecting crop or
livestock improvement in crop-livestock mixed systems may end up degrading
the environment. Policy initiatives that tend to favour intensification of staple
Productivity and Chemical Composition of Maize Stover and Rice Straw Under…
1.2 Importance of Maize and Rice on Livestock Feed
in Tanzania
In Tanzania, as in other countries in East and Southern Africa, 50% of the smallholder farmers also keep animals (Thornton et al. 2002). Livestock provides milk,
meat, income from sales of highly demanded livestock products to the increasing
urban populations (NEPAD 2005), manure for fertilisation of crops and draught
animal power to ease the drudgery and burden of hand cultivation. Increase in
human population has led to an expansion of cropping land especially in high agricultural potential areas along the high- and lowlands of the country. Available land
for forage production and grazing has become less. Instead, more crop residues,
mainly maize stover and rice straw, are contributing enormously to livestock feed in
the larger part of the year. Due to population growth and land scarcity in Kenya
highlands, for example, smallholder dairy farmers obtain up to 34% of total feed
from crop residues (Romney et al. 2003).
The principal constraint of cereal crop residues as feed for livestock is nutrient
deficiencies for growth, production and reproduction of the animals. Cereal crop
residues have deficient crude protein and minerals and high fibre content. The
digestibility of these residues is therefore low. Efforts to improve the quality of
cereal crop residues include breeding, agronomical practices and utilisation strategies. Vaswani et al. (2016) reported that different varieties of maize fodder differed
substantially in their chemical composition. They found higher concentrations of
minerals and nitrogen content in improved as compared with regular types. In an
assessment of the nutritive value of whole maize stover and its morphological fractions, Li et al. (2004) found that the leaf had the highest nutrients and the stem rind
had the lowest. These workers supported the development of a device that can separate different stover parts so that they can be used more efficiently for different
purposes. Amongst the strategies for utilisation of low-quality cereal crop residues
are urea treatment and supplementation with leguminous multipurpose tree leaves.
The benefit of improving stover and straw quality through improved plant nutrition
is somewhat less reported. Since increased biomass of stover and straw can feed
more animals and leave some portion for soil cover, it is an essential advantage of
improved plant nutrition.
1.3 Addressing Sustainable Intensification of Maize and Rice
Crops as Food and Feed in Tanzania
Intensification in this context means improved efficiency of crop and livestock
production, with reduced greenhouse gas production per unit of crop and livestock
products and more crop and livestock products per unit of water. Neglecting crop or
livestock improvement in crop-livestock mixed systems may end up degrading
the environment. Policy initiatives that tend to favour intensification of staple
Productivity and Chemical Composition of Maize Stover and Rice Straw Under…