Take a targeted approach to remaining fluke free

Press release

September 2014

After last year’s fierce fluke challenge and with the wet and warm conditions having continued this year,1 farmers are right to remain on their guard and think carefully about how best to protect their flock from the disease as the autumn/winter period approaches.1

Caused by the parasite, Fasciola hepatica, liver fluke is no longer thought of as being strictly seasonal, although the disease is still most rife during the wetter autumn and winter months in many areas. The spectrum of disease seen at this time ranges from acute disease, now occurring from July to December, to chronic disease beginning towards the end of the winter period.  Each form of fluke has different developmental stages of the parasite as its main culprit so treatments need to be specifically targeted and correctly timed to ensure sheep remain fluke free.

Acute fluke can be a reason for sudden death in sheep as well as causing anaemia (paleness), rapid weight loss, abdominal pain and breathing problems. This form of the disease is strongly associated with immature fluke burrowing through the liver tissue and causing damage, with as many as 1000 immature fluke in the animal but potentially few or no eggs in the faeces.

Sub-acute disease is a problem later on in the autumn season, leading to weight loss, reduced appetite, inactivity and inability of animals to stand up. These signs are seen as the level of immature fluke reduces and the number of adult fluke increases. Finally, from January onwards, chronic disease becomes more commonplace resulting in reduced fertility, gradual weight loss, anaemia and ‘bottle jaw’. Overall, fluke can result in huge financial loss for farmers due to fatalities, reduced live weight gain, effects on fertility and slaughter house condemnations.

So how can farmers protect their flock? Ultimately a variety of factors need to be taken into consideration when deciding on how and when is best to treat. This will include the farm’s fluke history, animal factors, forecasts, the season, the likelihood of resistance and the choice of flukicide. Taking advice from a vet or animal health advisor is the best way to ensure a protocol tailored specifically to the individual farm’s circumstances that will help prevent production losses and maximise profits.

During autumn, killing immature fluke is the priority with increasing focus on adult fluke as the season progresses. In high risk areas or on farms with a known history of fluke, preventative treatment starting in late August or September is advised, with multiple doses throughout the autumn/winter period likely to be necessary.2 While always an important factor, choosing the right flukicide is crucial when developing a strategic programme. Being strategic means taking all of these factors into account and targeting treatment accordingly.

Closantel (Flukiver® 5% w/v Oral Suspension) is effective against adult and immature fluke, successfully reducing fluke egg laying and hatchability as well as stunting any surviving fluke. With up to 13 weeks duration of action3 giving farmers the confidence of continued protection.  Resistance is another big consideration with the widespread use of triclabendazole (TCBZ) having led to resistance in this country.4 This means it’s important to choose treatment wisely and remember to rotate flukicides. Closantel (Flukiver® 5% w/v Oral Suspension) successfully targets susceptible fluke that are resistant to TCBZ, ensuring that treatment has the desired effect. 

Not only could wet areas experience an unexpectedly high risk this year2, even generally drier areas may also be at risk after the widespread fluke challenge from last year.5 However, although conditions may be conducive to fluke development, a considered and targeted approach to preventative treatment can help make sure farmers are not caught out by the destructive disease this season.

1.NADIS Parasite Forecast July 2014. http://www.nadis.org.uk/parasite-forecast.aspx

2.NADIS Parasite Forecast September 2013 Summary – ‘Liver Fluke Forecast 2013/2014’  

3.Maes et al, Comparative efficacy of closantel and triclabendazole against Fasciola hepatica in experimentally infected sheep. The Veterinary Record, Vol 127 No 18, 450-452 (1990) http://www.ncbi.nlm.nih.gov/pubmed/2275080

4.SCOPS – Endoparasites. Liver Fluke http://www.scops.org.uk/endoparasites-liver-fluke.html

5.NADIS Parasite Forecast August 2013 Summary http://webinars.nadis.org.uk/media/19794/13-08_parasite_forecast_summary__e_w_.pdf

Flukiver® 5% w/v Oral Suspension contains 50mg/ml closantel Legal Category POM-VPS.

Advice on the use of this or alternative medicines should be sought from the medicine prescriber

Use Animal Medicines Responsibly www.noah.co.uk/responsible

For further information contact Elanco Animal Health, Lilly House, Priestley Road, Basingstoke, Hampshire, RG24 9NL, Tel 01256 353131, Fax 01256 779510 Email elancouk@lilly.com      

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