Introduction

Where is the non-seasonal rainfall region?

This region generally has non-seasonal or uniform rainfall (350-850 mm) extending to winter dominant rainfall areas within the eastern Riverina. Some areas tend to summer dominance with respect to rainfall (notably the Monaro). There are four sections within this region:

• The south-western area (including the eastern Riverina) with hot summers and cool winters (includes the towns of Condobolin, West Wyalong, and Wagga Wagga).
• The tablelands area with warm summers and cold frosty winters (includes the towns of Bathurst, Orange, Yass, Young, Goulburn, Cooma); and
• The coastal area with warm to hot summers that are more humid and cool winters (includes the towns of Bega, Batemans Bay).
• The eastern Riverina (includes the towns of Finley, Narrandera and Griffith, Lockhart and Corowa) with hot summers and more winter rainfall dominance.

The region extends from an east-west line through Warren in the north to the NSW/Victoria border and west from the coast to a line from Nymagee (west of Nyngan and Tottenham) through to the Victorian border just west of Finlay.

This corresponds with the DrenchPlan region (NSW DPI)

These region boundaries are approximations only as seasonal temperature and rainfall variations affect worms. A map of the regions is shown below.

What worms are covered in this program?

Roundworms

The most important roundworms in this region are:

• Scour worms
  • Black scour worm Trichostrongylus colubriformis /Trichostrongylus vitrinus (increases in the south)
  • Small brown stomach worm Teladorsagia (Ostertagia) circumcincta
• Barber’s pole worm Haemonchus contortus

Also important but mainly for young sheep

• Thin-necked intestinal worm Nematodirus species

Barber’s pole worm

In this region, barber’s pole worm is often a problem, therefore the Barbervax^® vaccine should be considered if it is cost-effective compared to 4-6 weekly monitoring of worm egg counts during high risk periods and treatment with a short-acting drench or closantel.

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 is an internal parasite that occurs in parts of this region depending on the distribution of the intermediate host snail. It can affect sheep severely, sometimes causing deaths. The life cycle differs from the simple life cycle of roundworms, so control strategies are different.

This program relates to roundworms. To control liver fluke, see the relevant section at Appendices: Further information on sheep worm control for NSW non-seasonal rainfall region.

Other worms

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