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Australia's resource for control of worms, flies and lice in sheep,
and worms in goats

Fast Fact: The confusing world of tapeworm nomenclature (names)

A client received notification that his lambs had bladder worm. At the same time, another client complained that his laparoscopic AI man was having trouble visualising the uterus because of bladder worm. What could they do about these pestiferous worms? The thing is, bladder worm is not a worm, and it's not in the bladder, but is, instead, the intermediate, infectious stage of a tapeworm that lives in dogs. Nothing to be done for the sheep, but you can break the life cycle by worming the dogs.

Now, this tapeworm is called Taenia hydatigena in the dog, and the cystic intermediate stage in the sheep is called Cysticercus tenuicollis (bladder worm). So many tapeworms in dogs, foxes and cats (usually labelled Taenia something) have intermediate stages in sheep, cattle, pigs, rabbits and humans that are called Cysticercus something. Turns out that the early scientists did not realise that they were dealing with different life stages of the same parasite in different species. The names originally assigned have stuck. To make matters more confusing Taenia hydatigena/Cysticercus tenuicollis also gets the moniker “false hydatid”. Unlike hydatids, humans cannot be infected by Taenia hydatigena, so at least the “false” part is right.

Feature articles

How do you learn?

Introduction by Paul Nilon, Nilon Farm Health, Tasmania

At uni (all those years ago) some students never attended a lecture: they borrowed others’ notes (no handouts in those days) and did OK. On the other hand, your correspondent was very much an audio learner. If I missed a lecture it was struggle-street to get up to speed from texts or borrowed notes.

Lectures from the 2018 Paraboss Conference are on the website. While insomniacs may watch whole lectures, for the next few months snippet-links will be provided to address specific issues. The lectures were delivered by researchers and notable consultants to veterinarians and other technical types. However, the audiences that the conference organisers targeted were veterinarians and advisers providing services to producers. The presentations were very user-friendly. Please provide feedback on how useful you find this format. 
>> Read more.

Occident and Orient: West meets East on what is needed for sheep to become immune to worms

Introduction by Paul Nilon, Nilon Farm Health, Tasmania

You would be well aware that weaners become (relatively) immune to worm infection provided they have adequate nutrition and ongoing exposure to worms at the right time. Importantly, your lambing time and location (west versus east) determine the age at which sheep can be expected to be parasitically robust. This video, presented by Drs Caroline Jacoson and John Webb Ware, gives a great explanation of when we can expect young sheep to become immunocompetent, and the differences the west (Mediterranean climate) and the south-east winter rainfall patterns can make. If you understand this you will get a High Distinction in the exam. Please also take note of John Webb-Ware's video on the cost of dags. 
>> Read more.

Bladder worms on a liver (marked x). Source: www.djoralaekni.com
Do you know what dags cost you?
Why don't goats get drunk?
LiceBoss has 8 great tools

Have you ever seen a drunk goat? Considerations in drench doses for goats?

Introduction by Paul Nilon, Nilon Farm Health, Tasmania

Unlike sheep, goats do not develop high levels of worm resistance. To complicate matters they have an extraordinary liver capacity (so you won’t get them drunk), and therefore able to metabolise drenches very rapidly, so the standard sheep doses are inadequate. Dr Sandra Baxendell gives a great review of drug choice (including toxicity), dose rates and residues in this video. 
>> Read more.

Another take on genetic resistance?

Introduction by Paul Nilon, Nilon Farm Health, Tasmania

The April report linked to information on using ASBVs and visual scoring to reduce the risk of strike. To get a handle on the potential gains and progress to date in breeding for resistance to breech strike spend some time at this video as AWI’s Geoff Lindon addresses the topic. 
>> Read more.

The risks in a risk-based approach

Introduction by Paul Nilon, Nilon Farm Health, Tasmania

Brian Horton’s suite of LiceBoss tools has great algorithms for deciding the need to treat and treatment options. They should be your first stop in the lice decision-making process. If you are not familiar with them take a moment to see what they offer. As Lefty Kreh would say, “You’ll be amazed”.

However, here are a few other things you should put into the equation, particularly if the tools take you down the “no treatment/monitor path”.

  • Your own risk aversion: if you are unwilling or unable to monitor flocks closely, or just don’t like risk, take the least risky option (usually premature shear and treat).
  • Internal biosecurity: if you decide not to treat, do your gazing systems and infrastructure support monitoring?
  • Merino versus cross-bred (XB) flocks: Patently, the cost of severe derangement in Merino flocks will be more costly than in XB flocks. Against this, is that, prem. shearing will be more costly in Merino flocks (although combing length has come back in recent years). You may need some help to budget the costs of different options.
  • The opportunity to intervene: if you opt not to treat, will you have the chance to give a long-wool treatment or prem. shear? Obviously, lambing is the big issue: the 8 weeks or so from the start of lambing to easy handling can be a real issue. However, do not forget other difficulties: cropping commitments and the effect they have on your flock movements, or maybe just the start of the school football season.
  • Trading opportunities: the more you rely on store sales the more likely you are to treat pre-emptively. 

>> Read more.

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