Tips on avoiding acidosis when finishing beef cattle
In the Autumn 2022 Animal Health Ireland (AHI) Beef Helthcheck newsletter, Teagasc’s beef specialist Aidan Murray explained how acidosis can occur in beef cattle, as well as how to identify it and tips on avoiding it. Murray outlined that once silage quality drops below 67%-68% dry matter digestibility (DMD), the more feasible option for finishing cattle may be to feed concentrates ad lib with minimal roughage.
The advantages of ad lib feeding are improved and predictable cattle performance, better kill out, and quicker turnover of cattle.
Feeding an ad lib concentrate diet is costly and involves a higher level of feed management to avoid digestive upsets.
A number of factors can cause acidosis, including when cattle are introduced to high levels of meal too quickly. A lack of fibre in the diet (below 10% on a dry matter basis), as well as irregular feeding patterns and a change or over-processing of concentrate diets, are all factors which can cause acidosis.
Acidosis will lead to an increased risk of laminitis and liver abscesses. Key to any nutritional feeding strategy is to minimise the risk of this occurring.
Signs of Acidosis:
- Animals with acidosis will show obvious signs of pain such as kicking at the belly, grinding teeth, going off feed and developing signs of colic. If severe enough, they will have the additional sign of a grey coloured scour and may become dehydrated;
- Acidosis may also cause softening of the hooves and lead to lameness;
- Dung will become loose and bubbles will be present.
Murray explained that farmers can reduce the risk of acidosis when using high concentrate diets and offers a few tips on avoiding an outbreak.
Tips for avoiding acidosis:
- Feed troughs should never be allowed to go below 5% of feed remaining;
- Concentrate feed should be introduced gradually to cattle. You should aim for 21 to 25 days to adapt cattle to their new diet. Starting with a daily 3kg feeding rate, and gradually increasing by 1.5kg every four days until the target level of feeding is achieved, is advised to minimise the risk of digestive upsets;
- Avoid changing the concentrate formulation during the finishing period;
- It is essential that the diet contains a source of long fibre, which is typically straw fed ad lib (minimum 10% of total dry matter intake).
In Teagasc Grange, animals on ad-lib concentrates are offered good quality silage as the long fibre source and it typically will make up 10% to 15% of their dry matter (DM) intake.
Murray added that concentrate for all finishing cattle should be above 0.92UFV/kg fed.
Cereals should make up the primary ingredient in any finishing beef cattle concentrate. Cereals contain starch, which promotes the growth of propionic and lactic acid-producing bacteria in the rumen.
While high inclusion levels of cereals are desirable, it is recommended that starch levels should not exceed 25% to 30% of the total finishing beef diet.
Including a source of digestible fibre in the ration, e.g. beet pulp or soya hulls (up to 20% to 30% inclusion of concentrate formulation) can help aid rumen function and reduce the risk of acidosis.
Ground cereals should not be used at high feeding levels. Rumen buffers such as sodium bicarbonate and lime flour can help maintain rumen pH and can act as an insurance policy against acidosis.
Where individual cattle show mild signs of acidosis, a drench of 112g of sodium bicarbonate in 600ml of water can be administered orally followed by a half dose a few hours later.
Cattle should be offered a diet with additional forage and reduced grain while recovering from acidosis and then built gradually back up on concentrate.
In severe cases of acidosis farmers should seek veterinary assistance immediately.