Preventing parasite problems in livestock - Elders Rural Services
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Preventing parasite problems in livestock

Research by Meat and Livestock Australia (MLA) estimates that internal parasites cost the Australian livestock industry approximately $529 million a year.

This includes production losses, reduced animal health and decreased carcase yield as a result of internal parasites such as worms, flukes and protozoa. Thanks to the ideal conditions of last season in most parts of the country, we have an increased larval level on pastures. According to Elders livestock production coordinator, Rob Inglis, the parasite issue is still, and will continue to be problematic as we move into late spring and summer.

“Late rain (after winter feed has dried off) will remove much of the nutritive value of the dry feed,” Rob explained.

“This will prompt livestock to selectively graze the better-quality areas of the paddock which has a two-fold effect:

  1. Higher stocking rates in these preferred grazing zones, and
  2. Shorter – often green – pasture length which increases the odds of stock ingesting larvae.”

Be alert for Barber’s Pole

Rob said that while all parasites are an issue, the parasite of most concern at this time of the year is Barbers Pole worm (sp. Haemonchus).

“They are prolific egg layers meaning larvae numbers can build up very quickly,” he said.

The Barbers Pole worm resides ostensibly in the fourth stomach (abomasum) and is a blood sucking parasite. Rob said symptoms to look out for include: lethargy, depression and anaemia (in acute cases). He warned it can be hard to detect as sheep, or cattle, with high Barber Pole infections do not scour.

Take action now

Rob said it is important to act now with preventative measures. He offers the following tips.

Have a holistic worm management strategy. Don’t rely solely on chemicals.

Avoid set stocking with one species. Rotate paddocks, or species, at least every three weeks and worm test between rotations – it’s not just about the worms in the stock, it’s also what’s in the paddock.

Always use combination drenches. Using single actives, even when adhering to a stringent rotation programme, will invite the development of resistance.

Conduct regular worm counts on your stock, particularly young (less than 18 months) and late pregnant or lactating females. The tables below help determine the worm risk for sheep and cattle respectively.

Worm risk matrix – sheep

Risk FactorsHighMediumLow
Age< 1 yo2 yo & CFA3, 4 & 5 yo
Condition score< 2.52.5 to 33+
Pasture quantity (kg DM/Ha)< 800
(2.5 cm high)
800 – 1500
(2.5 to 5 cm high)
(>5 cm high)
Grazing history
(last 3 to 6 months)
•lambing ewes
•sheep < CS 2.5
•sheep < 1-Y-O
•sheep CS 2.5 – 3
•sheep 1 to 2-YO
•capsuled sheep
•adult dry sheep CS 3+
LactationLambing to markingMarking to weaningDry
WeatherWarm (>15o) and wetCold and wetHot and dry
Feed qualityLush greenMatureDry
FEC300+100 to 300< 100
Last drench> 6 weeks4 to 6 weeks< 4 weeks

Worm risk matrix – cattle

Risk FactorsHighMediumLow
Age< 1 yo2 yo & CFA3, 4 & 5 yo
Condition score< 2.52.5 to 33+
Pasture quantity (kg DM/Ha)< 1500
(10 cm high)
1500 – 3000
(10 to 15 cm high)
(>15 cm high)
Grazing history
(last 3 to 6 months)
•Calving cows
•Cattle < CS 2.5
•Weaner cattle

•Cows CS 2.5 – 3
•Yearling cattle

•Cows CS 3+
LactationCalving to markingMarking to weaningDry or empty cows
Feed qualityLush greenMatureDry
FEC200+100 to 200< 100
Last drench> 6 weeks4 to 6 weeks< 4 weeks

Contact your local Livestock Production Advisor for the latest information on parasite control. They can arrange a Faecal Egg Count Reduction Test (FECRT) which are also vital to identify what drenches are effective as part of an integral management program.

Many Elders branches now have FERCT machines which can produce results in as little as 10 minutes for a minimal cost. They are available at the following branches:

  • Ballarat
  • Griffith
  • Wagga Wagga
  • Gundagai
  • Dubbo
  • Goulburn
  • Yass
  • Cowra
  • Young
  • Launceston

For expert advice you can trust speak to your local Livestock Production Advisor.

Find your local branch
1. Meat and Livestock Australia


The information contained in this article is given for the purpose of providing general information only, and while Elders has exercised reasonable care, skill and diligence in its preparation, many factors (including environmental and seasonal) can impact its accuracy and currency. Accordingly, the information should not be relied upon under any circumstances and Elders assumes no liability for any loss consequently suffered. If you would like to speak to someone for tailored advice relating to any of the matters referred to in this article, please contact Elders.

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