Making and using molasses-urea blocks
-as supplementary feed for cattle
FOR MANY cattle and small ruminant famers, access to adequate pasturelands is becoming a challenge, and the need for supplemental feeding has increased significantly with the use of agro-byproducts such as rice bran, molasses and wheat middling. Molasses, a source of high energy, may be used to offset some of the deficiencies resulting from this situation. However, because it is a liquid, some difficulties are experienced with transportation, storage, handling and distribution.
Using Molasses Urea Block (MUB) can improve the utility of this feed resource, not only by overcoming its handling and storage problems, but also offering the opportunity to incorporate other nutrients to improve feed quality.
The inclusion of urea and mineral in the block improves the ability of the cattle to digest feed. The utilization of the urea in ruminants, however, calls for care in order to avoid toxicity problems. The consumption of urea by animals must be limited and progressive. A very special way of distributing urea to ruminants is to mix it in the molasses to make Molasses Urea Blocks (MUB). MUB is a solid high-energy supplement containing nitrogen and minerals for ruminants grazing animals on low-quality pasture. It is made from molasses, urea, and mineral, with a binder such as cement, quick lime or slaked lime. It can never be a complete feed and must be fed along with roughage. MUB allows for the regulated use of urea in a limited and progressive manner. It increases the efficiency of roughage utilization resulting in increased milk yield. It may also improve fertility in animals where mineral deficiencies occur.

COMPOSITION
The composition of the blocks can vary in accordance with the purpose of the blocks, type of animal, type of production and the season of the year. Other ingredients can be incorporated, such as poultry manure as a source of nitrogen, and drugs for treatment against parasites. Many ingredients can be used to make MUB in accordance with the availability, nutritive value, price, easiness of utilization and their influence on the quality of the blocks. The ingredients used locally are classified as follows:
Urea: This is a source of nitrogen, which can be digested by cattle. It is expected to provide nitrogen likely to be deficient in the feed of ruminants. Its consumption should be limited in quantity and spread out over time in order to avoid toxicity and regulate the level on ammonia in the rumen; this would aid in the better degradation of the cellulose matter.
Molasses: Molasses is a source of rumen fermentable energy source or carbohydrate. It is a palatable carrier for urea and minerals. It is also a source of trace elements and some macro elements such as sulphur, calcium, iron, potassium and a good source of B vitamins. The taste and smell of molasses are very appetizing and make the block more attractive to the animals.
Absorbent: The primary function of the absorbent/ fibre is to absorb molasses, which is the major ingredient in the block. Wheat and rice brans for example have various uses. They have good nutritive value and provide energy, protein and phosphorus. They also absorb the water obtained in the molasses and provide the block with structure. The best sources of fibre are dried leaves from forage trees such as Glyricidia spp., sugar cane bagasse, chopped hay and rice straw. Before using fibre, it must be chopped into small pieces, dried and passed through a 1-2 cm screen.  
Salt: This is added both as a source of nutrient and to prevent the animals from eating too much of the MUB. Feed blocks are generally meant to be taken on a ‘little and often’ basis. However, some animals may consume more than is necessary at a time. This may lead to urea molasses toxicities. High levels of salt tend to reduce intake.
Binder: Agents that have been employed to hold other ingredients together in the feed blocks are called binders. These include; quicklime, slaked lime, plaster and cement.  

PROPORTION OF INGREDIENTS
The literature has indicated several proportional compositions. The focus of table 1 will be on three different compositions.
Ingredients    1    2    3
Rice bran %    30    30    20
Molasses %    35    45    50
Minerals %    15    0    0
Urea %    2.5    10    10
Salt %    2.5    5    10
Cement %    15    10    10
Table 1: Composition of Different Blocks

The essential materials needed to make a MUB are: Moulds, ingredients, mixing equipment, scale, mixing pans/drums. 
In making the blocks, the water-to-cement ratio is very important, as it will determine the final quality of the block. The quality of the water used depends on the amount of cement. The ratio is 100 parts of cement to 37 parts water by weight. The following procedure should be observed while making the MUB:
1.    Weigh all ingredients
2.    Dissolve the urea and salt in hot water
3.    Mix urea/salt solution with filler/c cement
4.    Mix cement paste with molasses to uniform consistency
5.    Line the moulds with plastic/paper
6.    Pour mass into moulds and compact it
7.    Leave for one to two days for blocks to harden.   
The quality of the block should be: smooth and even with the ingredients very well distributed throughout the block, hard enough so that it is not easily squashed between the fingers and resistant enough not to break when a person steps on it.
The cost per block depends on the ingredients used, their unit cost and the size of the block.