ALWAYS READ THE LABEL
Users of agricultural (or veterinary) chemical products must always read the label and any Permit before using the product, and strictly comply with the directions on the label and the conditions of any Permit. Users are not absolved from compliance with the directions on the label or the conditions of the Permit by reason of any statement made or not made in this publication.
The product trade names in this publication are supplied on the understanding that no preference between equivalent products is intended and that the inclusion of a product does not imply endorsement by NSW Department of Primary Industries over any other equivalent product from another manufacturer.
HGPs are pellets implanted in the ear to stimulate increased weight gain by up to 20% and also to improve feed conversion.
Various types are available, all with similar action and results. However, some are longer acting than others. Select the product best suited to the duration of feeding.
There is no scientific evidence of any harmful effects to human health from eating meat from carcases of cattle that have been treated with approved (registered) HGPs when they are used correctly — that is, in accordance with instructions on the label.
However, certain markets have concerns about these substances. These may be generic markets, such as the European Union (EU), or individual market contracts in any marketplace. To maintain market access for Australian beef and offal exports to the EU, the Union requires Australia to ensure that such product comes only from animals that have never been treated with HGPs. From 1 December 1999, producers will only be able to supply the EU market if their property is accredited as ‘HGP-free’ under the Department of Agriculture and Water Resources EU access scheme.
All cattle implanted with hormonal growth promotants (HGPs) must be permanently identified with an approved triangular earmark, in addition to the palpable marker in the HGP.
There are strict requirements on the use of HGPs in Australia, and HGPs can be purchased only from a registered outlet. Producers who do not use HGPs are required to provide appropriate declarations when consigning their cattle for sale or slaughter, if they want to describe their cattle as ‘HGP-free’.
Before introducing any grain at all, feed cattle on hay for a few days to get them used to being handfed and to satisfy their appetites. Then introduce rations containing grain and roughage (dry weight) in the proportions shown in Table 11. By gradually introducing cattle to high-grain rations, the chance of grain poisoning and feed sickness is reduced.
|Grain (%)||Roughage and minerals (%)|
During cold, bleak weather, increase roughage and decrease grain by 10% (i.e. go back one step) until conditions improve, otherwise stock are likely to suffer digestive upsets. At any sign of excessive scouring or digestive upset, decrease grain by 10% (i.e. go back one step) for a few days. Many grain sickness problems can be prevented by adding 2% sodium bentonite to the ration, particularly during the build-up phase. Alternatively, virginiamycin (Eskalin®) has been successful.
Any factor that causes variation in intake, such as inclement weather or palatability of feed, or that changes the availability of the carbohydrate, for example a change in grain type or how finely the grain is ground, may cause problems at any time, not just in the period of grain introduction. Any hammer mill or roller changes are important here (see ‘Feed processing’ in the section Feed).
Once-daily feeding can be satisfactory if troughs are large enough and weather is favourable. Otherwise, feed more frequently. The trough should be just about empty when the next feed is due. Do not have cattle waiting at empty troughs for the next feed. Do not leave stale feed in the troughs.
Stock should eat to capacity. For every 100 kg liveweight, cattle will eat an average of 2.7–3 kg of dry matter daily if the ration is palatable, but this will vary throughout the feeding period. For example, one 300 kg steer will eat 9–10 kg of feed a day if the ration has an average dry matter of 90%. However, if the roughage component is silage, as in ration B (in the section Buying feed on a feed value basis) with a dry matter content of 30%, then the same 300 kg steer could eat between 12 kg and 14 kg daily (12.3–13.9 kg) for the same dry matter intake.
Allowance must be made to increase the daily ration, as the steer gains weight during the feeding period.
A 300 kg steer spends 80 days in the feedlot. He gains weight at 1.3 kg per day. At the start he eats over 9 kg of a 90% dry matter ration every day, and at a finished weight of 404 kg he is eating just over 12 kg of the ration per day. His average weight was 352 kg and his average consumption was nearly 11 kg of the ration daily.
Feed bunk management is of primary importance in preventing digestive upsets. It is essential to recognise that even slight digestive upsets will affect growth rates, and therefore your profitability, well before an animal is recognisably sick. Feedlot margins are generally so small that if you need to treat an animal it is too late — your profit on that animal is probably gone.
Feed intake will vary from feed to feed, depending on a variety of factors. Every effort must be made to minimise this variation.
Apart from the previously mentioned ration changes caused by the weather, you may need to alter the amount fed, according to how much is left in the bunk. If some animals are off their food, this leaves more for others, particularly if a full feed is added when there is still some left in the bunk. The others may then overeat, get a bellyache, be off their feed the next day, and then try to make up for it the next. If this happens, you will end up with many animals with a low-grade acidosis.
To minimise this ‘yoyo’ pattern of eating, check how much is left in the bunk, and only make up the difference with the next feed. This way there is not so much left for the gorgers to gorge. If there is often feed left over, check your calculations — you may be feeding too much.
Thorough mixing of feed, so that all ingredients are distributed evenly, is extremely important. Ask around for the best types of feed mixers before buying.
Troughs should be checked daily, perhaps more often in very hot weather, to ensure there are no problems with supply. Clean out as required, but at least once a week to avoid a build-up of contamination with dung and grain. Apart from the hazard of manure, grain washed from cattle’s mouths into the trough will ferment rapidly and cause a variety of problems, including digestive upsets, or souring of the water, which can affect the water’s palatability. If cattle drink less because the water supply is contaminated, feed intake and therefore weight gain will be reduced.
Feed bunks should be cleaned out as required, but we suggest at least weekly. It is important to have feed in front of the cattle most of the time (approximately 90% of the time). However, be careful you don’t keep topping up the troughs and allow feed in the bottom layer to get stale. If the feed gets wet and goes mouldy, it will probably cause health problems, or reduce feed intake.
Another problem could arise with urea, if troughs have not been emptied before fresh feed is added. If the urea settles to the bottom of the trough and if some animals do empty the trough after several days of the trough being topped up, then they may eat toxic amounts of urea (see ‘Urea poisoning’ in the section Cattle health in feedlots).