Benefits of feeding Urea Molasses Mineral Block as a feed supplement to ruminants and the precautions to be taken in its use

Introduction
The production of livestock is an integral part of farming systems. The principal forages used in India for feeding livestock are crop residues and dry grasses. These crop residues are low in nitrogen, minerals, vitamins, high in fiber and lignin, low in digestibility and thereby,limiting its intake by the animals. Feeding of such lowgrade feeds as the major part of ruminant diet result in low nutrient intake and thus, in the low productivity in animals.The performance of the animals on such diets results often in sub-optimal performance, which is reflected in sluggish growth, delayed maturation, longer inter-calving periods and poor milk yield. Strategic nutrient supplementation is essential in this scenario to improve the use of these poorquality roughages. Considering the availability and price of concentrate mixture, poor farmers can hardly afford them. To overcome this limitation, animal nutritionists across the world have shown that the nutritional value of crop residues can be enhanced if it is complemented by deficient nutrients (Makkar, 2002).
The Urea Molasses Mineral Block (UMMB) was developed at NDDB (1983) and has been further enhanced at IVRI (Garg et al., 1998). Supplementation of Urea Molasses Mineral Block (UMMB) can show promising effects on improving the use of nutrients and also the productivity of animals (Prasad et al., 2001). UMMB supplementation can increase feed digestibility by up to 20 percent, increase the nutrients received by animals, and increase feed intake by 25 to 30 percent (ESGPIP, 2007). It can be fed throughout the year, but during the dry season or when the animals graze low-quality fodder, they are more beneficial. Liquid supplements based on molasses with added nitrogen, minerals and vitamins have recently been shown to improve growth rate and reproductive performance in cattle as another approach to increase nutrient utilization. The benefits for feeding UMMB are:
a) Safe and uniform micronutrient delivery vehicle
b) Safe delivery Vehicle for NPN
c) Increase NPN utilization
d) Vehicle for delivery of molasses or fermentable rumen carbohydrates to rumen microbes
e) Reduce dustiness of concentrate feed
f) Reduce feed sorting
g) Increase the feed intake as a whole and enhanced palatability
Urea-molasses-mineral block (UMMB) is a strategic feed supplement for ruminants that promote the growth of rumen microbes throughout the day with a constant source of fermentable nitrogen. UMMB supplementation significantly increases feed intake, milk yield, and growth rate and is, therefore, a cost-effective approach in maximizing the use of locally available feed resources for increased productivity. UMMB provides fermentable nitrogen, energy, and minerals intermittently through licking, which is necessary for optimum microbial growth. Microbial protein can add 30-40 % of an animal’s crude protein requirement. UMMB supplementation in the ration is quite beneficial, especially when fed crop-residue-based diets, as ruminants, can produce microbial protein from non-protein nitrogen.
Molasses is noted for its sugar content and sugars usually contribute 60-65% of the solids in sugarcane molasses. Increasing the rate of carbohydrate fermentation could result in more effective capture of rumen degradable protein and improved supply of metabolizable protein to the dairy animals. Urea is a non-protein nitrogen compound; the nitrogen portion of urea is used as the building block for the production of protein by rumen microbes. Most urea contains about 46% nitrogen and protein contains 16% nitrogen. Therefore, when urea is converted to protein, the crude protein equivalent value of urea is about 281%. Urea contains no other useful feed component such as energy, minerals, or vitamins. Ruminant, through rumen microbial agency convert urea to the protein via ammonia and carbon dioxide obtained from the degradation of soluble carbohydrates. The excessammonia released from urea is transported to liver, where it is reconverted to urea to get it detoxified and then excreted out through urine.
Composition of UMMB
UMMB is made from various ingredients, each of which in the mixture has its own contribution. In general, it consists of Molasses, Urea, Mineral mixture, Salt, Calcite Powder, Bentonite, Cottonseed meal, Deoiled mahua seed cake, Wheat bran, and crushed maize. The composition of the Urea Molasses Mineral Block is given below. The composition may vary according to the availability of feed ingredients.

Precautions while supplementing UMMB
Feed to ruminants only (sheep, goats, and cattle).
Do not feed to monogastric animals i.e., horses, donkeys, or pigs.
Do not feed to young ruminants less than six months of age (kids, lambs).
Blocks should be used as a supplement and not as the basic ration.
A minimum of coarse forage in the rumen is essential.
Never give blocks to an emaciated animal with an empty stomach. There is a risk of poisoning due to excessive consumption.
The quantity of blocks fed to sheep and goats should be limited to 100 grams/day while for cattle it should be limited to 500-700 grams/day.
The blocks should never be supplied in ground form or dissolved in water as this can result in over consumption
Supply sufficient amount of water ad-lib.
References are available upon request

by Amir Amin Sheikh Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu