Cost of lice

  • Cattle lice generally have little economic impact on animals and are best left untreated.
  • Heavy infestations are uncommon but can cause anaemia and production loss.
  • Few treatments are registered for lice alone so consider timing of treatment for cost effective control of multiple parasites.

In most cases in Australia lice do not reach levels of infestation likely to cause significant reduction in weight gains or milk production. Most Australian studies have shown little economic benefit from the application of louse treatments. This is particularly so in pastured cattle where lice generally only become apparent in late winter and spring and then drop away naturally with loss of the winter coat in summer.

However, lice infestations can make cattle rub against objects causing damage to fences or other infrastructure (Figure 1). Louse infestation can also give a ‘rough’ appearance to cattle which may result in a lower price at sale. The effects of lice feeding also cause light flecks and spots in cattle hides that only become apparent after tanning. Rubbing to relieve irritation from lice can cause scratch damage to skins. Occasionally sucking lice species (in particular the short nosed sucking louse) can reach high levels that can cause anaemia and production loss, although this is uncommon in Australia.

In feedlots where cattle are in close proximity to each other, infestations can spread quickly and the use of induction treatments that provide lice control is good practice. Usually a product that provides protection against multiple parasites will be most suitable for this use. Cattle that are under stress from poor nutrition or disease and older animals tend to be more susceptible to lice. It is common to see elevated numbers of lice in drought affected cattle and lice treatments may be required in these situations.

Figure 1. Calf affected by an infestation of cattle sucking lice. Image credit Jenny Cotter
Figure 1. Calf affected by an infestation of cattle sucking lice. Image credit Jenny Cotter