The Cost of Roundworms

Roundworms cost the sheep and wool industry more than $430 million dollars per year (Lane et al. 2015); up from the $350 million dollars estimated by Sackett et al (2006). The impact of roundworms represents the highest animal health cost to the Australian sheep industry.

The annual cost of roundworms is about $6.00/head being lowest in the sheep/cereal zone and highest in the summer high rainfall zone (where barber’s pole worm predominates). About 80 per cent of the annual cost is associated with lost production and the remaining 20 per cent with the costs of control.

Adoption of the WormBoss worm control program QLD/NSW summer rainfall: Tablelands and slopes reduced the annual cost of worms to a self-replacing Merino enterprise from $11.09/ewe, under typical regional management, to $5.80/ewe (Kelly, 2011). One reason for an increase in the cost of roundworms is the worsening situation with drench resistance.

A good example in Australia of the cost of developing drench resistance was provided in Western Australia, where scour worms predominate. Over a period of one year, Merino sheep were treated with drenches that were either 65, 85 or 100 per cent effective at removing roundworm infection. The annual production loss in wool and sheep (in comparison to the 100 per cent effective treatment) amounted to (in 1996 dollars) $6.60 for the 65 per cent effective drench and $2.45 for the 85 per cent effective drench (Besier et al, 1996).

References:

Besier, B; Lyon, J; McQuade, N (1996) Drench resistance : a large economic cost (dpird.wa.gov.au)

Kelly, GA (2011) PhD thesis, University of New England, Armidale, NSW Australia Investigating the effect of gastrointestinal nematodiasis in Merino sheep on the Northern Tablelands of New South Wales and implications for Integrated Parasite Management

Sackett D., Holmes P., Abbott K., Jephcott S., Barber M. (2006) Assessing the economic cost of endemic disease on the profitability of Australian beef cattle and sheep producers, Meat and Livestock Australia, Sydney. pp. 119.

Watch the video extract from the ParaBoss Conference 2018 on the costs of scouring, presented by Dr John Webb Ware.