Beating bloat this spring

Beef producers particularly in southern Australia need to be vigilant now and in coming weeks to minimise stock losses from bloat as near perfect conditions align for strong legume growth.

This is a warning from Dr Leah Tyrell, researcher with the University of Melbourne Mackinnon Project, who will speak about bloat prevention strategies at Wednesday’s MLA-supported More Beef from Pastures event at Alpine Angus , Rosewhite.

“Some producers may have already seen bloat as it can occur on highly improved pastures during winter,” she said.

“However, the present lush conditions of early spring are ‘classic’ for producing high risk grazing situations that require careful management.”

Prevention tactics

Leah said weaners and yearlings are generally considered the most ‘at risk’ stock class, however, while most losses occur in this age group, she said it is usually because they are allocated the best pasture.

“If placed on lush pasture, mature cows are just as prone so producers should consider their paddock allocations carefully and move at-risk animals to pastures with lower legume content during hazardous periods,” she said.

“If this isn’t an option and you run a beef-sheep operation, you can consider crash-grazing legume-dominated paddocks with sheep, which rarely suffer from bloat, and then turning cattle onto them,” she said.

Cattle are particularly at risk when they are moved, so Leah recommended providing roughage at least two to three hours prior.

“The extra roughage will reduce pasture intake and increases saliva production which produces sodium bicarbonate that buffers the rumen and mucins that break down stable foam,” she said.

“In set-stocked situations, cattle should be fed roughage daily if they are blowing up.”

Leah said products to prevent or minimise bloat include:

Capsules and additives: Bloat capsules containing monensin are presently unavailable (they may return to market next year), however, there are other anti-bloat preparations (oils and detergents). Oils and detergents can be applied to water troughs (either directly or through in-line dispensers) or can be administered directly to stock in the form of lick blocks and loose licks.

• Risks – Leah warned that anti-bloat preparations dispensed in water will only work if there are no other water sources available and can be less effective in winter due to animals drinking less. The cost benefit depends on the cost of product and the ability of the product to prevent bloat. Lick blocks are relatively expensive and it is difficult to know if all animals are accessing them.

Pasture spraying: Daily spraying with anti-foaming agents such as paraffin emulsified in water can work in situations where intensive strip grazing is undertaken.

• Risks – Leah said all the grazing area must be sprayed and it is usually expensive and rain will wash off spray.

Treatment

Leah said animals mildly affected by bloat can be drenched with an anti-bloat preparation and, after dosing, should be moved around to encourage the preparation to mix with the frothy rumen contents.

“For animals in moderate distress, a stomach tube or, if not available, a section of garden hose can inserted down the throat and into the stomach (protected by poly pipe in the mouth to prevent crushing) to relieve gas build up and to administer anti-bloat agents,” she said.

“In an emergency, vegetable oil (250-500ml) and paraffin oil (100-200ml) can be used and, again, move the animal around after treatment.”

Other liquids and fuels such as kerosene and diesel are not edible, may contaminate meat, are hazardous to health and should never be used.

Leah said animals that are severely bloated and distressed need rapid relief.

“In these situations, there is often no time to wait for a vet and the producer will need to relieve the pressure in the rumen,” she said.

“A wide bore trocar or cannula can be used but often in severe cases this will not be enough and the producer will need to make a small incision with a clean sharp knife, high on the left flank.”

Leah said a veterinarian will still be needed to irrigate the abdominal cavity, clean and stitch the wound and give antibiotic treatment to prevent infection.

More information
Dr Leah Tyrell E: ldtyrell@unimelb.edu.au

The Alpine Angus More Beef from Pastures day, ‘Where to for the Beef Industry VI’ will be held at the stud’s sales complex at 1138, Happy Valley Rd, Rosewhite, Victoria.

To register contact Di Rees, of the Mackinnon Project T: 0418 748 603 E: d.rees@unimelb.edu.au

Bloat management resources:

http://mbfp.mla.com.au/Herd-health-and-welfare/Tool-67-Diagnostic-tool/Bloat

http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0009/111411/Bloat-in-cattle-and-sheep.pdf