WRML.2017-11-06.lev vs Osters.buying sheep-hazards.Graham Centre etc

In this issue:

Smeal on levamisole v Ostertagia in cattle
Buying sheep – ‘health hazards’
NSW DPI and Synthetic Biology
Graham Centre 2018 Calendar of Events
Blood and plasma donation: effect on exercise
(Good) culture beats strategy
Tip for the Melbourne Cup??
Aussie bush etiquette
Digital Resource Lifespan

Smeal on levamisole v Ostertagia in cattle

You might say levamisole (LEV) is one of the first modern anthelmintics. It came onto the Australian market about the same time as thiabendazole (TBZ), about half a century ago (1960s). How time flies.

Nilverm and Ripercol (LEV), and Thibenzole (TBZ), became household names, at least in country areas.

Although its usefulness has been limited to varying extents by the rise of resistant worms (endoparasites), not least in small ruminants, LEV is still a useful drench active (and easy to use and relatively cheap), especially as a component of multi-active combination drenches.

In cattle, it is useful against a range of worms, resistance notwithstanding, but its weak spot, relatively speaking, is Ostertagia ostertagi – small brown stomach worm – the most important gastrointestinal roundworm of cattle in temperate regions of the world.  (Every drench active has its strengths and weaknesses, depending on your point of view). LEV can have useful activity against adult Ostertagia, but is not great against inhibited L4s (4th stage larvae) in the abomasum.

While perusing a book by Dr Malcolm Smeal, a former NSW Agriculture veterinarian / research scientist, I came across the following. Much of it won’t be new to you, but some of the detail may be.

“Levamisole preparations which are given orally and subcutaneously have a high efficacy against O. ostertagi worms acquired during autumn and winter by calves less than 1 year of age. By comparison, the efficacy of oral levamisole against Type 2 adult O. ostertagi burdens in 15 to 18 months old cattle in summer shows a large variation between 50% and 80%. Levamisole is not very effective against inhibited larvae, as only about 30% of the burden is removed”.

“Pour-on formulations of levamisole at dose rates of 7.5 and 10 mg/kg give low percentage efficacies of 30% to 70% against adult worms during cold winter months, whereas treatments applied during the warmer months of the year have a higher anthelmintic efficacy of 80% to 90%. Levamisole is absorbed poorly percutaneously, but climatic conditions appear to affect the rate and amount of absorption of the drug into the systemic circulation. Because of the variable Australian climates, a much higher dose rate than that recommended is required (this would constitute ‘off-label’ use -Ed.) if dermally administered levamisole is to control O. ostertagi and other nematodes.” 

Perhaps formulation chemistry has improved somewhat since the mid-1990s, when Malcolm Smeal wrote his book, but note the findings of Sargent and others (2009) regarding variable efficacies of pour-on triclabendazole products administered at different times of the year.

Sargent RM, Chambers M, and Elliott T, 2009. Seasonal differences in the efficacy of pour-on formulations of triclabendazole and ivermectin or abamectin against late immature liver fluke (Fasciola hepatica) in cattle. Veterinary Parasitology 161 (2009), 133-137. This paper reports variable efficacies for two different pour-on triclabendazole products. The efficacies varied from 73-78% (winter) to 90-92% (spring) to 99.6% (summer).   This and other results are summarised in an issue of WormMail:  https://wormmailinthecloud.wordpress.com/2017/04/10/wrml-2017-04-10-flukicides-summaries-efficacies-synergistic-combinations-resistance-management/

Smeal MG (1995). ‘Parasites of Cattle’, Veterinary Review No.32, The University of Sydney, Post- Graduate Foundation in Veterinary Science, pp. 358.  (Section on pages 30-31).

Buying sheep – ‘health hazards’

An older (May 2007) DPI Primefact by Plant and Seaman: “Buying sheep can be a health hazard”  https://www.dpi.nsw.gov.au/__data/assets/pdf_file/0017/142217/buying-sheep-can-be-a-health-hazard.pdf

A newer one (September 2017): Buying sheep – the general biosecurity
duty, and how to avoid health hazards. September 2017, Primefact 1602, first edition
Animal Biosecurity and Welfare. (NSW DPI)  https://www.dpi.nsw.gov.au/__data/assets/pdf_file/0009/739107/Buying-sheep-the-general-biosecurity-duty-and-how-to-avoid-health-hazards.pdf

The latter one is OK with respect to resistant worms, but the suggestion of a quarantine drench like ML+BZ+LEV in many cases won’t cut it these days (in AU at least) – also there is no mention of resistance to flukicides? (in the Sept. 2017 edition; about to be updated) …. BUT...the Primefact does refer readers to another DPI Primefact  (and also to WormBoss ) for more information.

The other DPI Primefact: Quarantine drenching – don’t import
resistant sheep worms. August 2016 PrimeFact 477 Second edition.

NSW DPI and Synthetic Biology

 Uploaded (to YouTube) by Deborah Hailstones (NSW DPI) on Oct 25, 2017.

“DPI’s role in Australian node of groundbreaking international project in synthetic biology, ‘Yeast 2.0’, led by Macquarie University”.”Interviews with key stakeholders:
Dr Phil Wright – Chief Scientist, DPI
Prof Sakkie Pretorius – Deputy Vice Chancellor Research, MQU
Distinguished Professor Ian Paulsen – Director, Synthetic Biology Lab, MQU
Dr Hugh Goold – NSW DPI Postdoctoral Research Scientist, MQU
Dr Natalie Curach – Synthetic Biology Development Consultant, MQU
Dr Deborah Hailstones – Manager Science Strategy, CSB (Chief Scientist Branch, DPI)

[Note – you can also make the captions (interviewee names) visible by clicking on the settings tab ( bottom right) in the video and select ‘Subtitles: English – Camtasia’]. CSB is currently trying to master video-editing to embed the captions more smoothly!)”

Graham Centre 2018 Calendar of Events

2018 Graham Centre Calendar of Events

The Graham Centre for Agricultural Innovation at Wagga Wagga NSW is an alliance between Charles Sturt University & NSW Department of Primary Industries.

Blood and plasma donation: effect on aerobic and anaerobic responses in exhaustive, severe-intensity exercise

PubMed – NCBI: https://www.ncbi.nlm.nih.gov/pubmed/23668764

(Good) culture beats strategy

‘Culture beats strategy every day’. Thus said Simon Smith (Secretary, NSW Dept of Industry) recently. (Video message on the NSW DPI intranet)

OK, we’ve all heard it before (it’s an ancient concept, not a modern invention), but it’s worth pondering. To clarify, Simon added: it’s not so much what you will say you will do, but what you actually do. ‘Walk the talk’, I guess.

I was trying to think of an example.  Maybe the All Blacks?  Is it their game plans (strategy) that is most significant, or their culture?

Tip for the Melbourne Cup??

A (cynical? worldly-wise?) senior colleague recently told me: “If there is a horse called ‘Self Interest’ in a race, always back ‘Self Interest'”.

Aussie bush etiquette

Aussie Bush etiquette-frm kq 2017-11

Digital Resource Lifespan



SL, Armidale,  Mon 6 Nov 2017

‘without fear or favour’

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