Arthur Le Feuvre, Editor, WormBoss News
August 2012
 

Some recent comments from producers about tapeworms caused me to ask the WormBoss team plus some other eminent parasitologists and consultants 3 questions about the impact of tapeworms on lambs and sheep generally.

The questions:

• In your experience or research, have you ever: (a) seen, (b) read, or (c) proved that the sheep tapeworms (M. benedini/expansa) cause any deleterious effects in sheep of any age/condition etc?
• Do you consider that sheep producers who drench for tapeworms are wasting their time and money?
• Is there any situation where you would consider recommending to a producer that they should treat sheep for tapeworms?

The answers are enlightening and hard to misinterpret!

Paul Nilon, Nilon Farm Health, Tasmania:

To your 3 questions:

• No, (b) no and (c) no. We see prime lambs choked with tapes growing at 200g/day. The only ones at risk are those that scoot on their bums across the road while being moved to the yards.
• Worse than a waste. Heavy burdens killed with Praziquantel can block the intestine inducing Pulpy Kidney. Have seen it once. Has also been reported in the literature.
• Two situations: (a) they don’t like the Feds and want some tax credits (b) they have a lot of roads to cross getting to the shearing shed. But only if you have portable yards.

David Hucker, Para-Tech Veterinary Services (Vic):

I concur with Paul Nilon’s assessment.

Colin Trengove, Sheep Health Lecturer, UA Roseworthy campus:

I agree all the way with Paul Nilon, although haven't seen lambs scooting.....perhaps the tapes are more prickly in Tasmania.

Lewis Kahn, Associate Professor, Animal Science, UNE:

We recently completed a trial evaluating the effect of treating for tapeworm on growth rate of prime lambs in the New England region of NSW. Lambs received effective drenches (Abamectin + Levamisole) with or without Praziquantel (to control tapeworm) at monthly intervals for two months. The objective of the trial was to determine if control of tapeworm provided benefit for growth of prime lambs where roundworms were controlled.

Tapeworm count started at 100epg in both groups but treatment for tapeworm reduced this to close to zero. Roundworm count started at about 2000epg (mostly Barber’s Pole worm) for both groups and was 700epg one month later and 100epg at the end of the trial.

Lambs grew slowly at about 86 g/d and treatment to remove tapeworm had only a small effect with those lambs growing at 94 g/d. We concluded that tapeworm is unlikely to be a major barrier for lamb production and other management factors such as feed quality and roundworm control are most important.

Steve Love, Veterinarian, State Coordinator-Internal Parasites, NSW Dept. Primary Industries, Armidale:

It is highly unlikely that producers will get a measurable response (production/less scours/dags) to treatment specifically for Moniezia.

If they do, it is unlikely that the response will be economic. But, it IS highly likely that they will become fixated on tapes rather than important worms (Barber’s Pole, Trichs, Ostertagia).

Furthermore, treat for tape if you like, but make sure that the broad-spectrum in there with the Praziquantel works against the REALLY important worms.

Combinations of Praziquantel with Levamisole, Benzimidazoles or Ivermectin will flatten the tapeworms, but, unless a Drenchtest has shown otherwise, may be deficient in killing the important worms.

Brown Besier, Principal Veterinary Parasitologist, DAFWA, Albany WA:

Apart from the lack of evidence of a consistent benefit from removing Moniezia, the concern is the possible shift of effort away from the real worm problems. 

There are all sorts of stories about Moniezia blocking intestines etc, but even in New Zealand, where you’d presume the climate would favour it more than in most parts of Australia, the locals are dubious about the need for specific treatment.

David Rendell, Livestock Intel, Hamilton:

A comparative drench response trial was conducted on 300 prime lambs on a south-western Victorian property in late spring/early summer 2000.

Adding Praziquantel to the drench of 8-14 week old prime lambs was associated with a small reduction in weight gain of 9 gm/day over the 42 days of the trial which is not statistically significant.

Rendell DK (2001) “Productivity response in prime lambs to Praziquantel and ML’s”

Proceedings of the Aust Sheep Vet Society - AVA Conference Melb 2001.

The combined results of this trial and the Kahn trial indicate no productive response is gained from treating prime lambs for tape worm.