Focus
 
Expanding the Menu: Transforming By-products into Nutritious Feed
Safouh Rihawi
An innovative project uses non-conventional agro-industrial by-products to improve the nutrition and productivity of livestock in the drylands.

T
he picture of the drylands, particularly in the Central and West Asia and North Africa (CWANA) region, doesn't seem complete without a herd of sheep grazing on dry brush. But this common image belies the very basic challenge of raising a healthy, productive herd in an often overgrazed, degraded, water-scarce environment. While the productivity of the vast rangelands in the region is diminishing, the growing rate of urban migration and population growth is fueling an ever-increasing demand for animal products, particularly meat and milk derivatives.

Feed blocks made from tomato by-products.
But the supply of livestock products is not satisfying the demand. Small-ruminant meat production in the West Asia and North Africa (WANA) region increased from 1.4 million metric tons in 1970 to 2.9 in 2000; meat consumption, on the other hand, increased from 1.5 million metric tons to 3.0 in the same period, resulting in a deficit of 100,000 metric tons that is partially covered by imported meat. By developing low-cost alternative sources of feed and improving livestock nutrition, farmers in the region have the opportunity to raise their income by capitalizing on this demand without overgrazing the rangelands.

The concept of using supplemental feed made from agricultural by-products is not new. Farmers routinely take advantage of the benefits of incorporating left-overs such as cottonseed cake, sugar beet pulp, and wheat bran into animal diets. However, farmers are often unaware of the many other options available to them. So ICARDA researchers recently studied the potential of incorporating other ingredients in animal feed such as tomato pulp, molasses, burghul derivatives, crude olive cake, sesame cake, citrus pulp, sunflower cake, and mulberry leaves with promising results.

Tomato pulp
Every year Syria produces around 610,000 tons of tomatoes. After processing, however, 42,000 tons of highly nutritious pulp remains unused. Most of the pulp is produced in July and August—two months of the small-ruminant mating season when the only feed available on dry pastures is straw and stubble. The challenge with using tomato pulp is its high moisture content of 18-20%. The extra moisture means that the nutrients remain soluble and special care must be taken during processing to prevent their loss. There is also a higher chance of fermentation and mold.

ICARDA researchers tested three efficient, low-cost methods to preserve and use tomato pulp--sun drying, ensiling, and adding it to other feed blocks. Sun drying the pulp or mixing it with straw or crude olive cake proved to be effective in preserving the pulp and produced a highly nutritious feed with 21% crude protein and 9 MJ metabolizable energy. Ensiling, a method of preservation through acid fermentation in an airtight chamber, is traditionally done with barley or corn crops. Attempts to preserve tomato pulp using this method also proved successful and showed a slight increase in live-weight gain of sheep for a lower cost. Including tomato pulp in urea-based feed blocks produced a low-cost feed with high levels of crude protein and metabolisable energy equivalent to known concentrate feeds. All three options proved to be worthwhile giving farmers the option to choose methods that are appropriate to their budgets and facilities.

The idea of feed blocks has already proved to be very successful in Jordan. ICARDA worked in close collaboration with the National Center for Agricultural Research and Technology Transfer (NCARTT) to introduce and promote the use of feed block technology in Jordan. The project imported seven feed block production units from Iraq. They were given to women's associations and the private sector to produce feed blocks on a commercial scale. Farmers and extension agents were introduced to the technology at farmer field days and also through the television, radio, and press.

When ICARDA and NCARTT scientists heard of a tomato paste factory in the Jordan Valley that was having problems getting rid of its waste without polluting the environment, they were quick to see the potential in the situation. Scientists designed a machine to dry and grind the tomato by-product into a palatable feed. Researchers then contacted the nearby Der Alla Rural Women's Cooperative Society's feed block unit so that they could start incorporating the tomato-based by-product into their feed blocks.

Jordanian farmers were pleased with the feed block technology. They found that their sheep did not drop or eat their wool, habits that are triggered by malnutrition. They also realized that sheep and goat health improved due to a reduction in internal parasites. On-farm data showed that sheep and goats grew 20% faster when fed with feed blocks and sheep fertility increased by 20%.

Urea-Based Feed Blocks
Urea is an important source of nitrogen for small ruminants. However, it can be poisonous if ingested in large quantities. So ICARDA researchers tried to find ways to ensure that only appropriate amounts of urea reached the animals through their diets. One way to do this was to create feed blocks using urea and the cereal stubble left in the fields after harvest. Trials were conducted with farmers in northern Syria and researchers compared the use of traditional supplements, including barley, cottonseed meal and wheat bran, to the new feed blocks. They found that sheep fed with the feed blocks had a higher live-weight gain than those fed with traditional supplements. Using the feed blocks was also cheaper. The feed blocks only cost 0.9 SL/head/day (US$ 1 = 51.5 SL), whereas the barley, wheat bran, and cottonseed meal cost farmers around 2.5 SL/head/ day. The implications of this research is important for both farmers that normally use expensive concentrates and those that do not supplement cereal stubble with a source of urea.

Farmers in the region need a low-cost effective way to supplement their livestock diets during the mating season.

Mulberry leaves
Mulberry trees with red and white fruits are relatively common in northern Syria. ICARDA researchers found that these trees can provide a good source of quality feed for small ruminants. Mulberry leaves have a crude protein content of 18% and a dry-matter digestibility of 62%, similar to those of vetch hay, an excellent fodder also produced locally. This research was first initiated in Uzbekistan.


Future steps
The next step calls for spreading the message and forging networks
for the transportation of by-products to the fields to improve the quantity
and quality of milk and meat from small-ruminant systems. Now that
ICARDA researchers have identified the availability and benefits of using
these industrial by-products, farmers will need
to be educated about the new options available
to them. There is also great potential for the
establishment of agri-businesses for
manufacturing feed blocks, using these
by-products for the benefit of the farmers
in the region.
Dr Safouh Rihawi (s.rihawi@cgiar.org) is a Livestock Nutritionist at ICARDA.
 
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© 2008 International Center for Agricultural Research in the Dry Areas (ICARDA). See copyright and disclaimer information.