In simple terms, ad-lib feeding is giving a beef animal unrestricted supply of concentrates. You can NOT just start an animal on an ad-lib diet. Ideally, you should build them up to the diet over a period of three weeks. Table 1 outlines a time frame to build the animals up to an ad-lib diet.
As per Table 1, silage should be included ad-lib up to day 14, with straw introduced from day nine.
Straw ad-lib
By day 15, when you have your animals at 9kg of concentrates, silage should be removed from the diet and only clean fresh straw offered to the animals.
When your animals reach ad-lib, they need straw to ensure that the digestive system functions correctly. Animal performance is delivered from the concentrate, so there is no need to feed silage.
You can feed hay or silage, but you need to keep an eye on intake. If an animal eats too much hay, it will restrict their intake of concentrates and affect performance.
Constant access to fresh water is of utmost importance during ad-lib feeding
Around 1kg to 1.5kg per head per day of long fibre (10%), for example straw, is required to keep the digestive system operating effectively.
It is important to keep straw in front of animals at all times and to ensure that it is fresh and dry. If animals are eating too much straw, – in excess of 2kg per day – there may be issues concerning access to or palatability of the ration.
Research
Research at Teagasc Grange clearly shows that after 90 days on ad-lib meal, steer and heifer performance declines and daily feed costs start to outweigh animal performance.
Therefore, it is important that steers and heifers are close to 100kg to 120kg away from slaughter when starting ad-lib feeding and it is also important to sell cattle when they are fit for slaughter.
Bulls can be treated differently and can sustain high performance for over 160 days. In general, to encourage high animal performance, the higher the daily intake of concentrate the better.
Table 2 gives a guideline on how much meal different types and weight of animals will eat per day.
Intakes may exceed these guidelines for a few days after introducing meal ad-lib, but will settle back down quickly. If animals are not consuming this level of meal, the following areas should be explored:
Feeding a ration at this level means that you must take into consideration the inclusion of minerals in the diet.
The mineral inclusion rate in standard beef rations is based on up to 5kg to 6kg being fed per day.
Therefore, on an ad-lib system, you would be feeding twice the required level, which may lead to poor performance and risk of scouring. For an ad-lib ration, you should ensure that minerals are only added at 50% of the standard rate.
You should also be aware that changing the ration during the feeding period can have a negative effect on the animals.
The ration should be kept as consistent as possible. In the unlikely event that you have to change a ration, do so gradually. If possible, mix the two rations for a period.
Constant access to fresh water is of utmost importance during ad-lib feeding. A simple rule to follow is that four to six litres of water is required per kg dry matter intake.
Therefore, an animal eating 10kg of concentrates per day will require over 40l of water per day.