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Sheep

The Barbervax® vaccine program


Barbervax® is a vaccine against barber’s pole worm, which gives the Australian sheep industry a new weapon to fight an old foe. This vaccine provides a major alternative to drench-based control and will help manage drench resistance.

Barbervax will be of particular benefit in barber’s pole-endemic regions where frequent drenching may be necessary to prevent sheep deaths, and where anthelmintic resistance has reduced drench options.

The vaccine is given to sheep and lambs as a series of subcutaneous injections of 1 ml, at no more than 6-week intervals to cover the barber’s pole worm-risk season (in the NSW Tablelands, generally December to April).

It is important to understand that the first two vaccinations are not able to provide protection, but they prime the lamb’s immune system so that protection occurs following the third vaccination, and lasts for up to 6 weeks. Further vaccinations need to be given each 6 weeks while there is a barber’s pole worm risk or more frequently in those years and situations where animals are exposed to very heavy challenge from barber’s pole worm.

Once sheep have received a course of vaccine as lambs, a single boost in a subsequent season will typically provide 6 weeks protection.

The Barbervax Vaccination Schedule

NOTE: This schedule should be followed accurately; do not extend the gaps between vaccinations.

Barbervax is not a knockdown product; some drenches will still be required while immunity is establishing. Only the recommended pre-lambing and weaning drenches are shown in the schedule, however, other drenches may also be required; monitor as per your regional WormBoss worm control program and Drench Decision Guide.


The Barbervax vaccine being administered to a lamb during field trials
The Barbervax vaccine being administered to a lamb during field trials

Lambs or hoggets not previously vaccinated

This schedule best suits lambs born in September or October. For lambs born at a different time it is best to seek advice from your sheep advisor, your re-seller or email info@barbervax.com.au.

  • V1: The first Barbervax vaccination should be given at lamb marking.
  • V2: The second Barbervax vaccination, 3–4 weeks later.
  • V3: The third Barbervax vaccination, 3–4 weeks later, generally at weaning.
    This should be given with an effective drench to control scour worms as well as any early barber’s pole worm and the lambs should be moved to a prepared low worm-risk paddock, ideally where sheep have not grazed for 3 months.
  • V4: The fourth Barbervax vaccination, 6 weeks after the third vaccination.
  • V5: The fifth Barbervax vaccination, 6 weeks after the fourth vaccination.
  • V6: A sixth Barbervax vaccination may be required 6 weeks after the fifth vaccination if May is mild and wet.

NOTE: Vaccinations V4 and beyond may need to be given more frequently in those years and situations where animals are exposed to very heavy challenge from barber’s pole worm.

Hoggets vaccinated as lambs the previous year

  • V1: Give in November/December (earlier if spring is wet).
  • V2–V5: after V1, give at 6-weekly intervals while protection is required.

NOTE: Vaccinations beyond V1 may need to be given more frequently in those years and situations where animals are exposed to very heavy challenge from barber’s pole worm.

Breeding ewes not previously vaccinated (assumes a spring lambing)

  • V1: 8–9 weeks pre-lambing.
  • V2: 4–5 weeks pre-lambing.
  • V3: 1–2 weeks pre-lambing. This should be given with an effective pre-lambing drench to control scour worms as well as any early barber’s pole worm and the ewes should be moved to a prepared low worm-risk lambing paddock that has been prepared over the previous 6 months.
  • V4: lamb marking.
  • V5 onwards: after V4, give at 6-weekly intervals while protection is required.

NOTE: Vaccinations V4 and beyond may need to be given more frequently in those years and situations where animals are exposed to very heavy challenge from barber’s pole worm.

Breeding ewes vaccinated the previous year

  • V1: 1–2 weeks pre-lambing. This should be given with an effective pre-lambing drench to control scour worms as well as any early barber’s pole worm and the ewes should be moved to a prepared low worm-risk lambing paddock that has been prepared over the previous 6 months.
  • V2: lamb marking.
  • V3—V6: after V2, give at 6-weekly intervals while protection is required.

NOTE: Vaccinations beyond V1 may need to be given more frequently in those years and situations where animals are exposed to very heavy challenge from barber’s pole worm.

Key: V=vaccination, the number (1–6) refers to first, second (and so on) vaccination in the series given in one barber’s pole worm season.

You should also follow the recommendations in your regional WormBoss worm control program and Drench Decision Guide. It is strongly recommended that the worm egg counts of the lambs, hoggets and ewes are monitored. Ideally, a mob WormTest should be done 4–5 weeks after each effective  (i.e. not the priming doses) vaccination from the third vaccination onwards, so that the result is known before the next vaccine muster. The WEC results will inform whether a drench is required and a culture will give further information about the worm types present. It is important to remember that Barbervax does not replace the need for drench programs to control scour worms. 

Grazing management to prepare low worm-risk paddocks to avoid significant barber’s pole intake will further enhance the effectiveness of vaccination, and breeding for worm resistant sheep provides complementary longer-term worm control. Sheep in poor body condition or showing signs of worms may not respond fully to vaccination, and may require additional support.

Barbervax can be purchased from a number of suppliers (Grazag, Landmark and Walcha Veterinary Supplies). The price is between 68c and 92c per dose depending on pack size and supplier (at December 2016).

More technical details about Barbervax

  • Each 1 ml dose contains 5 ug native antigen + 1 mg saponin adjuvant.
  • It is administered as a 1 ml injection under the skin irrespective of bodyweight.
  • It may be given at the same time as Clostridial vaccine (e.g. 5-in-1 or 6-in-1), though at a different site.
  • It is sold in 250 ml and 100 ml packs, the contents of which should be used within 12 hours of opening. Any vaccine remaining should be discarded.
  • Its current unopened shelf life is 33 months and it should be kept refrigerated  (2–8°C), but not frozen.
  • Five or six doses are generally required during the summer barber's pole worm risk period. Sheep being vaccinated for their second season may need fewer doses than those not vaccinated the year before.
  • The vaccine is effective against all barber’s pole including drench resistant worms.
  • It is sustainable—vaccine resistance is unlikely to develop.
  • It has no withholding period or Export Slaughter Interval. Non toxic. Organic.
  • It slows the development of anthelmintic resistance in all worm species, as fewer drenches are used, so all worms are exposed to fewer drenches.
  • The vaccine is not effective against scour worms.
  • The Barbervax vaccine was developed by the Moredun Research Institute in Scotland and has been registered for use in Australia after extensive field trials in northern NSW, Australia funded by Meat and Livestock Australia.
  • The Barbervax vaccine is manufactured at  the Albany Laboratory of the Department of Agriculture and Food, Western Australia.

Goats

Barbervax® vaccine in goats

Barbervax vaccine was trialled in three NSW goat herds with a view to registration. The results were mixed.

The following paragraphs are extracts from the report:

"Barbervax, a vaccine for Haemonchus contortus infection of sheep: attempts to extend the registration claim to include goats" by David Smith for Meat and Livestock Australia, 23 February 2016.

 

"Three efficacy field trials with kids were performed in the Northern Tablelands of NSW with a view to obtaining caprine registration in Australia. Unfortunately the results were mixed: one trial worked well, a second showed some positive effects, but a third failed. Because the anti-vaccine antibody responses were similar in all three trials, the underlying cause of the variable vaccine efficacy is not understood.

It was concluded that the results were too variable for registration to be granted by the regulators.

At Guyra the counts of the vaccinates were significantly reduced relative to the controls by 73% on average, at Dorrigo the figure was also statistically significant at 44% but at CSIRO, at 17%, it was not statistically significant.


Figure. 1. Haemonchus egg counts of goat kids averaged from the third vacination (V3) to end of trial
Figure. 1. Haemonchus egg counts of goat kids averaged from the third vacination (V3) to end of trial

The use of Barbervax in goats would be “off-label” and must be done with a veterinarian’s prescription. Initially, the vaccine might be evaluated in a small portion of a herd and the worm egg count of treated and untreated animals regularly tested. 

Goat owners are reminded that Barbervax is a protective treatment against barber’s pole worm and when used in sheep relies on the use of effective anthelmintics for an initial “clean-out” of all worms, as well as ongoing use of drenches and worm egg count monitoring, as required, for scour worm control.