Introduction

What worm control regions are in Tasmania?

The high rainfall (prime-lamb) region

This region includes King Island, the North Coast between Wynyard and Launceston. These are the high winter rainfall areas with up to 1200 mm annually.

The medium to low rainfall (extensive) region

This region includes the north-east coast, the Midlands and Derwent Valley and the lower east coast. The rainfall is non-seasonal, between 350 and 600 mm annually.

The summer rainfall region

This region includes Flinders Island and in some years, the north-east coast. The medium to low rainfall region recommendations apply here, but the summer rainfall also predisposes to barber’s pole worms. Also, other areas in Tasmania with sheep on irrigated summer pastures may experience barber’s pole worm burdens in late summer and early autumn.

These boundaries are approximations only as seasonal temperature and rainfall variations affect worms.

A map of the region is shown below.

What worms are covered in this program?

Roundworms

The most important roundworms in Tasmania are

• Scour worms
  • Black scour worm Trichostrongylus vitrinus /Trichostrongylus colubriformis
  • Brown stomach worm Teladorsagia circumcincta
  • Thin-necked intestinal worm Nematodirus spp.

In summer rainfall areas:

• Barber’s pole worm Haemonchus contortus

Barber’s pole worm

In this region, barber’s pole worm is generally sporadic and of short duration, therefore the annual requirement for the Barbervax^® vaccine is less certain compared to 4–6 weekly monitoring of worm egg counts during high risk periods and treatment with a short-acting drench or closantel (seek veterinary advice before using unregistered products).

However, if your farm has periods of high barber’s pole worm risk for several months each year (which may occur in coastal areas or on irrigated pastures) seek professional advice as to whether the Barbervax vaccine program should be considered.

Liver fluke

Liver fluke (Fasciola hepatica) is an internal parasite that occurs in parts of this region depending on the distribution of the intermediate host snail (Austropeplea (Lymnaea) tomentosa).  It can affect goats severely, sometimes causing deaths. The life cycle differs from the simple life cycle of roundworms, so control strategies are different.  Liver fluke should be considered if there are cases of anaemia or bottle jaw in goats that are not associated with barber’s pole worm.

This program relates to roundworms. To control liver fluke, see Liver fluke control.

Please note: the ranges of barber’s pole worm and liver fluke are quickly being extended by irrigation.  Irrigated, grass-dominant pastures increasingly support barber’s pole worm in the north of the State in late summer and autumn.  Runoff from irrigation may create liver fluke habitat in all areas. 

Other worms

Gastro-intestinal parasites of minor importance, such as stomach fluke and tapeworm, are not covered.