Livestock nutrition
Lot feeding Merino lambs during a drought
Noel O'Dempsey, formerly of DPI&F
Key points
- In a drought it can be advantageous to wean early and lot feed Merino lambs rather than feed both the ewes and the lambs in the paddock.
- The decision to lot feed will depend on good budgeting, your workload and objectives.
- Important considerations are the anticipated duration of feeding, the cost of feed and the facilities required.
Time to wean
Lambs must be a minimum of 8 kg bodyweight. They should be drafted into two groups with lighter and poorer animals taken off and fed separately.
Facilities required for lot feeding
A well-drained yard with good shade, good fencing and trough water is required. A feeding area that can be closed off is useful.
The yard size will be determined by the number to be fed. The stocking rate required is 1500 to 2000 lambs per hectare.
Bulk grain handling facilities will reduce both the labour requirement and the cost. Bagged grain is more expensive and not as readily available.
Scales, to monitor live weight change, are useful.
Feed troughs must be sufficient to allow all lambs to feed at the same time. The minimum length required is 15 cm of double sided trough per lamb. The trough should be 60 cm wide. A weldmesh barrier down the middle keeps lambs from standing in the trough. Insufficient trough space accentuates the problem of shy feeders.
For water troughs one metre of edge is required per 130 lambs. The water supply must be capable of delivering up to four litres per head of good water daily. The troughs must be cleaned each day.
Husbandry
Vaccinate lambs with multi-valent clostridial and cheesy galnd vaccine (6 in 1) on introduction to yards and again four weeks later. The lambs can be marked at the second vaccination.
Drench all lambs on entry into the yard.
With the high stocking rate and the possibility of scouring, effective blowfly control is required.
At the daily inspection, sick lambs or shy feeders should be removed from the main mob into a hospital pen with a lower grain ration. Watch the droppings. If they get soft or putty-like, reduce the amount of grain and increase the roughage until the droppings firm up. Animals with grain poisoning can be treated with 15 g sodium bicarbonate (baking soda) in 600 ml of water. If necessary the treatment can be repeated.
Feeding
Initially, start with some coacher sheep in the yard with the lambs and feed good lucerne hay either to appetite or at 500 g per head per day. After three days start introducing grain. The grain percentage is increased by 5 per cent every second day until a ration of 70 per cent grain : 30 per cent lucerne hay is being fed. A higher level of grain may be fed but some roughage should always be available.
On high grain diets 1 per cent by weight of ground limestone and 1 per cent salt should be added. A commercial mineral premix would be a useful additive.
There is no advantage in crushing grain for sheep.
Vitamin A supplementation is advisable as the lambs will probably not have had green feed for three months; 500 000 IU should be sufficient.
A daily ration of 350 g maize and 150 g lucerne hay with 1 per cent limestone should allow a 15 kg lamb to grow at 150 g daily and a 25 kg lamb to grow at 100 g daily.
A daily ration of 475 g maize and 125 g lucerne hay with 1 per cent limestone should allow a 30 kg lamb to grow at 100 g/day.
Over a four month feeding period on the rations specified here the lambs should have gained around 12 kg. These growth rates are dependent on feed quality.
Quantity of feed in storage
You should have at least two weeks feed on hand at all times in case of rain or unavailability of feed.
Monitoring weight gain
Ear tag some sheep. These should be regularly weighed to monitor weight gain. Rations can then be modified to give the required weight gain.
Changing the feed
When changing the grain used or even batches of the same grain, do so slowly over 4 to 6 days to prevent digestive upsets.
Frequency of feeding
Daily feeding is required.
Costs
Maize has been used in this example, however other grains may be cheaper or more readily available. Sorghum, wheat and barley can be provided at the same weight. For oats the grain ration would have to be increased by 25 per cent to provide the same energy level. Oats have a higher fibre content so the amount of roughage in teh diet can be reduced.
Once the lambs are on teh full diet and doing well on the grain and lucern hay mix, the cost may be reduced by substituting poorer quality hay. This needs to be done over a 4-6 day period.
Since the costs of lucerne hay and grain vary widely it is impossible here to itemise exact costs for every situation.
However, if we assume both maize and good quality lucerne hay costs $220 per tonne, on property, then the ration cost for a four-month feeding period will be approximately $15 per head. The cost of labour and the required facilities should also be included.
There is no point finishing with small, stunted lambs. Growth rates of 100 g per day or above are ideal. Growth rates below 50 g per day will lead to increased mortalities and subsequently wool production will be reduced.
When to stop feeding
This will depend on rainfall and your objectives. If good rains fall, continue feeding the weaners in the yard for two weeks. They should then be fed roughage in the morning before being let out of the yards to feed. This will allow the lambs to adjust to the new feed. After a few days the lambs can be let out into a paddock with some older sheep.
If there is no rain, you are faced with a variety of decisions. The lambs may be shorn and sold or sold in the wool. They will be in good condition and you may be able to sell them, particularly the wether portion, into the prime lamb trade. Otherwise they can be put on grass with minimal supplementation, or kept in the feedlot.
Note: Rations and costs are given as a guide only due to the variability in feed quality, ingredient prices, and freight and animal performance.
Further information
For further information contact DPI&F on Telephone 132523 between 8 am and 6 pm weekdays, or or e-mail callweb@dpi.qld.gov.au
This DPI Note is also published on the DPI's PrimeNotes CD-ROM.
Information contained in this publication is provided as general advice only. For application to specific circumstances, professional advice should be sought. The Department of Primary Industries Queensland has taken all reasonable steps to ensure the information in this publication is accurate at the time of publication. Readers should ensure that they make appropriate inquiries to determine whether new information is available on the particular subject matter.
File No: SW0089 . Date created: July 1988 . Revised: November 2007
