Fortified molasses for survival feeding of beef cattle
When the quantity and quality of available feed becomes low, an energy source (as well as protein) is required. Molasses can be a cost effective energy source but is low in protein.
Research and grazier experience has shown that molasses fed in open troughs with added protein can be used successfully for drought feeding of cattle. Molasses lends itself to bulk handling methods suitable for drought feeding large numbers of stock.
The basic composition of molasses is:
- Dry matter: 76%
- Sucrose: 46%
- Reducing sugars: 20%
- Protein: 5.6%
- Phosphorus: 0.07%
- Sulphur: 0.73%
Queensland molasses is grossly deficient in protein, phosphorus and zinc. Copper and sodium are marginal. Other minerals exceed nutritional requirements. In terms of energy, 1kg of molasses is equivalent to 0.7kg grain.
Apart from extra protein there have been no responses to additives for medium term drought feeding up to 6 months, unless in a recognised phosphorus deficient region.
Molasses must be fortified (have added protein) to balance the feed. Feeding straight molasses is not cost efficient.
Sources of protein
There are two main types of protein. These are non-protein nitrogen (NPN) such as urea and true protein such as vegetable protein meals.
Urea is a cost-effective product for increasing the protein content of feeds, but the quality is less than that from vegetable protein meals.
Vegetable protein meals provide better quality protein to stock than urea. The total protein content, the amount of by-pass protein, amino acid composition and other factors such as energy and fat content vary between vegetable protein meals.
Proteins highly protected by processing (e.g. cottonseed meal) or formalin are relatively insoluble in the rumen (i.e. more by-pass protein). When digested by the animal they are of higher feed value compared to more soluble meals (e.g. rapeseed) that are easily broken down by the rumen microbes.
|NPN||Urea (46% nitrogen)||288|
|Hi pro' sunflower meal||38|
|`Lo pro' sunflower meal||32|
Fortified molasses mixes
The additives and their inclusion rates in molasses will depend on:
- the condition of the cattle
- the condition of the pasture - quantity and quality
- the level of performance required (e.g. maintenance or growth)
- the relative costs and availability of feedstuffs
- the handling equipment and storage facilities available
- safety - urea is not an option unless good mechanical mixing is possible.
In general, the better the condition of the cattle and the more dry feed available, the less additional protein that will be required.
Cattle in strong condition, some paddock feed
Mix 190% molasses + 10% cottonseed meal (by weight)
i.e. 1000 L molasses + 156 kg cottonseed meal.
92% molasses + 8% urea (by weight)
i.e. 1000 L molasses + 122 kg urea.
Mix 1 has an adequate protein content, but is much lower in protein than mix 2. About half of the urea in mix 2 can be used by the animal as protein. The high urea level creates a bitter taste which in turn controls intake.
Under the above conditions, recommended intake of either mix is:
- Weaners 1.0 to 1.5 kg/hd/d
- Dry cattle 1.5 to 2.0 kg/hd/d
- Lactating cows 2.0 to 3.0 kg/hd/d
Cattle in poor condition, little dry feed
Under these circumstances, both the quality of the mix and amount fed will have to be increased. Molasses with 8% urea (M8U) can be fed in this situation, but a mix using vegetable protein meal would be preferred.
85% molasses + 15% cottonseed meal
i.e. 1000 L molasses + 247 kg cottonseed meal.
88.5% molasses + 10% cottonseed meal + 1.5% urea
i.e. 1 000 L molasses + 158 kg cottonseed meal + 24 kg urea.
Required daily intakes of these mixes would be:
- Weaners 1.0 to 1.5 kg/hd/d
- Dry cattle 1.5 to 2.0 kg/hd/d
- Lactating cows 2.0 to 4.0 kg/hd/d
- Poor cows
- late pregnancy up to 6 kg/hd/d
- early lactation up to 6 kg/hd/d
Access to paddocks and handling/mixing facilities will often influence which mix is used.
Never use urea unless you have a reliable mechanical mixer. The mix that contains 1.5% urea can be considered if caution is taken.
Mixing fortified molasses
Molasses plus vegetable protein meal mixtures (MPM) are safe and generally palatable.
MPM mixes can be mixed relatively roughly, provided there is fairly even distribution of meal through the molasses. Equipment ranges from sophisticated molasses mixers through to shovels and various homemade paddles.
Urea on the other hand must be thoroughly mixed and completely dissolved. This is best achieved using a mechanical mixer for half an hour or more. A recommended practice is to mix the night before, let it stand overnight and then mix again the next morning before feeding out.
Urea is toxic if not mixed properly. Undissolved urea will float to the top of the mix forming a crust that is deadly when eaten.
Similarly undissolved urea will dissolve into the water on the top of the mix after rain. Cattle that drink this highly concentrated solution can be poisoned. This problem will not occur if the mixing is done properly.
Always add urea to the mix dry. Never add water. If the molasses is cold or thick, mixing becomes more difficult, and the mix may need to be left standing overnight before repeating the mixing procedure.
Introduction of fortified molasses
When using molasses plus vegetable protein meal mixes, the final mix is used from the start. For the first week, if possible, feed every two days so that eating habits and intakes can be monitored.
When feeding molasses and urea, always start with the final mix. Gradually building up the strength will allow stock to become accustomed to the bitter taste that will result in higher intakes of the final mix and therefore the increased possibility of deaths due to urea poisoning.
Feeding fortified molasses
All fortified molasses mixes are fed in open troughs (i.e. free access). Roller drum bases, half 200L drums, lengths of trough and round concrete troughs (400 to 700 L) are suitable and commonly used for feeding. Troughs with curved sides can prevent animals from regaining their feet if accidentally pushed in. Some drownings have occurred.
Ensure that there are sufficient troughs for the number of cattle being fed.
Twice weekly feeding is ideal. This means that enough feed is put out for 3-4 days at a time. It is common for cattle to run out between feeds, but this method restricts intakes and also evens out distribution between shy feeders and aggressive feeders. If necessary the frequency of feeding could be reduced to once per week, but with very palatable mixtures, stock will be without feed for several days.
With molasses and urea, the mix should preferably be kept in front of stock at all times. The bitterness of the mix should still make it possible to achieve this in twice weekly feeds. Feeding three times per week would be an advantage if there are problems with stock eating too quickly.
Using other vegetable protein meals
The suggested rations using molasses and vegetable protein meal have assumed that cottonseed meal has been used. Other vegetable protein meals with a similar protein content can be substituted at the same rate.
Current evidence also suggests that copra meal can also be included at the same rate even though it has only half the protein content. Generally, meals with a lower protein content should be included at a higher rate.
Various methods of mechanical mixing are successful. These range from an atom borer, drill attachment, cement mixer, through to truck mounted 5000L tanks fitted with paddles and driven by a 7.5kW engine.
A popular choice is a 1000 to 1500L tank on a trailer fitted with a set of internal paddles or 200mm auger spiral driven by tractor PTO, mounted engine, or ground drive.
Outlets from mixers should be at least 100mm diameter for quick delivery and be to the side in the driver's view.
Use of roughage with fortified molasses
Generally it appears that feeding roughage is not always essential when feeding fortified molasses. However, when there is no paddock roughage available, the high intakes of molasses may be eaten too quickly. Some animals may be affected by molasses toxicity or scouring. Only 0.5kg per day of stubble hay is required.
Considering the numbers of cattle that have been successfully fed molasses, graziers should not be unduly worried about molasses toxicity. Symptoms are rapid breathing and muscular weakness leading to coma. Affected animals should be taken off the molasses diet and fed hay.
Molasses is bought and carted in litres, added to meals or urea by percent weight and then feed in kilograms per head per day. This can become confusing.
1 gallon = 4.54 litres
1 litre molasses = 1.4 kilograms
1 gallon molasses = 6.36 kilograms
714 litre molasses = 1 tonne
1 litre water = 1.0 kilogram
As with all drought feeding techniques, segregation of the weaker animals minimises losses. Cost savings can be achieved by regulating the amounts and types of feed required by different groups of animals.
Keep horses separate from cattle when feeding fortified molasses as horses keep the cattle away from the mixes.
Cold and/or wet weather
During severe cold snaps or wet weather it may be necessary to feed additional hay to stock. The heat generated during digestion will assist to maintain body temperature.
End of drought
After drought-breaking rain cattle will tend to 'chase the green pick' and weak cattle may die. Continue to feed until adequate feed is available in the paddock. In some cases, cattle may need to be confined and fed to maintain adequate intakes.