UREA
MOLASSES MULTINUTRIENT BLOCKS (UMMB)
AS A FEED SUPPLEMENT FOR RUMINANTS
H Bheekhee
Agricultural Research and Extension Unit
ABSTRACT
Molasses is a major by-product of the sugar industry in Mauritius and is still under-utilised for livestock production because of legislation and handling problems. A combination of urea, molasses and other feed ingredients can be used to produce urea-molasses multinutrient blocks (UMMB) that can be fed to livestock as a supplement. The main objective of UMMB supplementation is to provide a constant source of degradable nitrogen throughout the day, to promote growth of rumen microbes in ruminants fed poor quality forage. Studies with cattle, goats and sheep elsewhere indicate that supplementation with UMMB resulted in increased milk yield and growth rate when no other form of supplementation was given. In Mauritius, studies have shown that UMMB can be utilised as a supplement in the smallholder dairy cattle production system as well as in the deer production sector.
INTRODUCTION
Ruminant livestock production is
almost entirely dependent on feeds consisting of fodder and crop residues. These
feeds are often of poor quality, usually deficient in protein and minerals. To
improve production, the efficiency of utilisation of the available feed
resources can be optimised by the use of supplements that provide the deficient
nutrients. Generally for such purpose, concentrates such as cottonseed cake and
cowfeed which are high in protein are used as supplements. The purpose of
supplements is to provide nutrients that are deficient in the basal diet and
nutrients needed for production. Some of these supplements can sometimes be
manufactured using locally available ingredients and agro-industrial
by-products.
Molasses which is a major by-product of the sugar industry in Mauritius, is a good, palatable and cheap source of energy for ruminants. Use of liquid molasses by small farmers, however, is very limited due to problems related to transport, storage and legislation. One strategy to get over this obstacle and increase the use of molasses is through the manufacture of urea-molasses multinutrient blocks (UMMB). The technique is to mix the different ingredients in a container and to pour the mixture in moulds to solidify into blocks. Major advantages of using the blocks are their convenience in terms of packaging, storage, transport and ease of feeding. Blocks can thus provide an avenue to maximize the use of locally available feed materials such as molasses and bran for feeding ruminants, thereby reducing the use of high cost concentrate feeds. This strategy of producing UMMB has been proposed by the International Atomic Energy Agency (IAEA) in order to develop affordable and sustainable supplementation packages for improving the productivity of smallholder farms.
DEVELOPMENT OF UMMB
Investigations at AREU have
led to the formulation of UMMB using locally available ingredients namely
sugarcane molasses, urea, common salt and wheat bran. Other ingredients such as
minerals, vitamins and a source of good quality protein like cottonseed cake or
soya bean meal are imported but readily available on the local market. Cement is
used as a binding agent. Studies conducted in Canada and USA on the utilisation
of cement and its by-products as minerals for animals did not reveal any
negative effect when fed up to a maximum of 3% of the total daily dry matter
intake (Aarts et al, 1990). The
proportion of ingredients used in the manufacture of two sets of UMMB, A and B,
using two different amounts of molasses is shown in Table I. The level of
cement as a binding agent is adjusted to obtain blocks of good texture and
hardness that regulate intake by the animals. To obtain a good setting, cement
needs a minimal quantity of water, just enough to make a paste for proper
mixing.
Table 1 Proportion of ingredients used in
the manufacture of UMMB at Curepipe Livestock Research
Station
Ingredient |
% by
weight (fresh
basis) | |
|
A |
B | |
|
Molasses (>80°
Brix) |
40 |
45 |
|
Urea |
10 |
8 |
|
Mineral Mixture |
5 |
3 |
|
Common Salt |
3 |
2 |
|
Cottonseed Cake |
5 |
6 |
|
Cement |
17 |
12 |
|
Wheat Bran |
20 |
24 |
Ratio water:cement is 2:5
All ingredients should be weighed
accurately before mixing. Mixing can be done either manually for small
quantities, or mechanically using a concrete mixer, or a horizontal paddle mixer
for large quantities. The sequence in which the ingredients are mixed is very
important. Urea is first added to
the molasses and thoroughly mixed. All lumps should be broken down to ensure
proper mixing and to avoid toxicity problems when fed to animals. Mineral mixture, cottonseed cake and
half of the amount of salt are then added, while mixing continuously. The remaining half of the salt is mixed
with cement and water to make a paste, which is then added to the molasses
mixture and thoroughly stirred to obtain a consistent paste. Wheat bran is added last, little at a
time and thoroughly mixed until the product is homogeneous. This product is then ready to be placed
in moulds.
Moulding and drying
Moulds can be made of wood,
plastic, iron or carton boxes, which may be of any shape and size. A plastic
sheet placed in the mould or an oil film prevents the block from sticking to the
wall and allows easy removal from the mould. Once the mixture is placed in the
mould, it should be left in a well-ventilated room to set. The mixture takes
about 48 hours to set, after which the blocks are ready to be utilised. For
cattle, 10-kg blocks seem to be convenient. Blocks wrapped in a plastic sheet or
left in carton boxes can be stored in a dry place for several months. Table 2
indicates the chemical composition of the two sets of UMMB, A and
B.
Table
2 Chemical
Composition of UMMB (% fresh matter basis)
|
|
A |
B |
|
Crude
protein |
27.5 |
30.5 |
|
Crude
fibre |
2.2 |
2.1 |
|
Fats |
1.4 |
0.3 |
|
Calcium (as
Ca) |
5.5 |
4.8 |
|
Phosphorus (as
P2O5) |
1.4 |
2.1 |
|
Ash (other than Ca
and P2O5) |
17.6 |
16.9 |
|
Carbohydrates,
sugars, etc. |
22.1 |
26.7 |
The dry matter (DM) content of block A is 77.7% and that of block B is 83.2%. The mean calculated metabolizable energy (ME) of the supplements A and B are 10.9 and 11.0 MJ/kg DM respectively.
FEEDING OF UMMB
UMMB must only be fed to
post-weaning, growing or adult ruminants and never to monogastric species or to
pre-ruminant calves, kid goats, lambs and deer fawns because of urea toxicity
problems. Since blocks are supplements they should always be used with a minimum
quantity of roughage. Blocks are introduced gradually in the diet of ruminants
during a transition period of about 2 weeks to enable the animals to adapt to
the new supplement. Afterwards, blocks are offered to animals without any
interruption. Blocks being palatable, are licked by animals according to their
requirement, thereby regulating the intake of urea so as to ensure its efficient
utilisation, without any risk of toxicity. The targeted daily intake by adult
animals should be 700 g/head for cattle, 150 g/head for deer and 100 g/head for
goats and sheep.
BENEFITS
Consumption of UMMB depends on the type of fodder or roughage and concentrates in the diet as well as on the physiological state of the animal. The positive effect of UMMB intake on overall performance of an animal will be more pronounced on a low plane of nutrition, that is, a crop-residue or straw-based diet. According to Hendratno (1997), there is a significant improvement in body condition and reproductive performance as well as an overall increase in milk yield. Also, higher amounts of molasses may be utilised not only as a feed component but also as a vehicle for urea, minerals and rumen non-degradable protein to cater for nutritional deficiencies.
MEDICATED BLOCKS
Another potential for UMMB supplementation that can be exploited is through the use of medicated blocks, for the control of pests and diseases. Animal species that can benefit from medicated blocks include deer, goats, sheep and young calves. In the deer sector, both the normal and the medicated UMMB can be used. These can prove to be highly advantageous especially in the extensive system of deer production where there is very little control over the animals.
REFERENCES
AARTS G, SANSOUCY R and LEVIEUX GP. 1990. Guidelines for the manufacture and utilisation of molasses-urea blocks. Animal Production and Health Division. FAO. Rome, Italy.
HENDRATNO C. 1997. Development and utilisation of UMMB as a feed supplement for ruminants. Paper presented at the First Regional Training Workshop (AFRA) on “Guidelines for developing supplementation packages”. Morocco. March 1997.