Liver fluke treatment for cattle and sheep

Liver fluke disease is a well-known parasitic infection of cattle and sheep which can cause serious production losses in these animals. The first question is: why is it necessary to control this disease? The immediate response may be that liver fluke can kill sheep, which is certainly true, but this is probably one of the lesser reasons for controlling it.

It is estimated that liver fluke disease costs Irish farmers up to €90 million annually in lost production. Let us consider the effects in sheep; this parasite causes considerable damage in all animals resulting in reduced weight gains of up to 30%, reduced fertility both in terms of conception and lambing rates, reduced wool growth and diminished wool quality and finally deaths as mentioned above.

While the latter may be more important to the individual farmer concerned, overall, the losses caused by the other effects is probably greater.

The Coen family from Mayo use Curafluke. Hear what they had to say:

Coen family from Mayo

Cattle

In beef cattle – the main effect is a reduction in weight gain which can be as high as 20%. The problem is that the animal may still gain weight but less efficiently than should be the case.

The damage to the liver is also an economic cost but as the farmer rarely sees this or may not be aware of the loss, there may be no inducement to do anything about it.

In dairy cows, the damage is more extensive with reductions in milk yield of up to 8% and impaired fertility, resulting in longer inter-calving intervals or even sterility for the year. However, while individual animals (sheep or cattle) require treatment to control infection, the most important reason for treatment in the long term is the control to reduce pasture infection so as to reduce exposure to the disease in the future.

Rafoxanide

It is important for farmers to know what product and more importantly what active they are using and what stages of fluke it controls. Rafoxanide has been widely used for many years throughout the world for the control of liver fluke. This active has been in general use since the 1970s and has been shown to be an effective and safe flukicide for general use – a claim which is extensively supported in the literature.
Rafoxanide is one of the salicylanilides which have activity against the liver fluke (Fasciola hepatica). Rafoxanide is highly effective against adult and immature fluke from 6 to 8 weeks of age with action against fluke as young as four weeks.

In addition, it has an excellent safety record and no evidence of resistance in fluke has been demonstrated.

Points to consider

What is the regime best suited to control the disease? It must be stated that there is no single broad solution. It depends on a number of factors, the animals (sheep or cattle), the preceding weather, type of land and farming practices. For example, wet versus dry weather, wet or poor  draining soil versus dry free draining soil and whether animals are out wintered or housed. It should be noted that animals do not develop good immunity to liver fluke so ongoing treatment is necessary.

Life Cycle

For effective control, it is vital to be familiar with the basic life cycle of the parasite and to determine the weak links in the chain of events. Liver fluke eggs are passed in the dung to pasture where they develop, infect the common mud snail (Lymnaea Truncatula) multiply and re-immerge and infest the pasture.
When the grass is eaten, the young attached flukes penetrate the gut and make their way to the liver where they become adults and start laying eggs to restart the life cycle again.

Life Cycle Summary:
  • Larvae are ingested on contaminated grass in typically wet areas mostly during late summer to winter. Liver fluke infection occurs in all parts of Ireland but is more prevalent in the west and in years when there is high summer rainfall;
  • Once ingested the larvae penetrate the intestine wall and move to the liver. They travel through the liver for 8-12 weeks causing significant damage;
  • Immature fluke then reach the bile ducts where they mature into adults. If left untreated, flukes can live for months to years. They feed on blood and produce thousands of eggs which are passed back onto pasture;
  • The eggs develop to a small larvae stage. They then must find and penetrate its intermediary host (the mud snail) which is more commonly found in wet areas. They develop through various larvae stages before leaving the snail;
  • Each infected snail can release up to 600 larval flukes back onto pasture from one fluke.
Lymnea snail

As you can see, there are two multiplicative stages in the life cycle; the first is in sheep and cattle when the eggs are produced, the second is in the snail host. The best way for effective control is to target and reduce these multiplying stages. Infected animals at pasture, irrespective of the time of year, will pass out eggs which if they fall on wet ground where the snails are present will continue the cycle.

Control should therefore be directed at minimizing the number of eggs reaching the pasture thus reducing the chance of infecting the snails and also to reduce the presence of the snails on the pasture. In Ireland, particularly in the west where rainfall tends to be higher, fluke eggs can infect snails and give rise to pasture infection any time throughout the year. It is therefore important to minimize the output of eggs through all seasons. In the drier parts of the country, eggs shed during summer are more likely to fail in their development unless they are shed into wet muddy sites.

On the basis of the epidemiology of the disease and taking into account the environment and species, the following can be used for effective liver fluke control for sheep and cattle.

Controlling Liver Fluke:

  • Improve drainage or fence off wet areas. Avoid poaching or grazing wet areas especially when fluke can be ingested, typically late summer to winter;
  • Dose bought in animals with appropriate flukicide before letting out to pasture;
  • It is recommended to dose in late spring / early to mid-summer to reduce the number of eggs on the pasture and thus reducing the number of snails becoming infected;
  • Fluke burdens can be monitored by using faecal egg counts, bulk milk tank samples and information from meat factories regarding infected livers;
  • In winter, dose animals at housing, 4-6 weeks after housing or both depending on type of flukicide used. It is recommended to use a flukicide like rafoxanide which also controls immature fluke at this time;
  • Rotation of anthelmintics is highly recommended to avoid the build-up of resistance. The emergence of resistant strains of fluke to Triclabendazole has been reported in Ireland. No known resistance has been reported to the use of Rafoxanide;
  • Estimate the weight of your animals accurately or weigh if possible. Avoid under-dosing to help prevent resistance. There is nothing to be gained by over-dosing;
  • Dosing should only be undertaken if the animal will not be going to slaughter after the withdrawal period, 60 days for rafoxanide. Make sure to check withdrawal periods carefully as there has been an increase in the withdrawal of some products;
  • Rafoxanide based products cannot be given to dairy animals producing milk for human consumption including during the dry period.
Reported Efficacies against F. hepatica4-week-old immature fluke6-week-old immature flukeAdult liver fluke
Rafoxanide45-98%87-99%99-100%

Irish Veterinary Journal, Vol 13, No. 9, Sept 2013 p474-481)

Curafluke (Rafoxanide 10% / Fenbendazole 10%)

Curafluke is a low volume fluke and worm drench which controls all major worms including Lungworms, Stomach worms (incl. Ostertagia Type II and Nematodirus) and Mature and Immature Liver Fluke in cattle and sheep. Other Univet products containing Rafoxanide include Ranide (Rafoxanide) and Univet Multidose (Levamisole, Rafoxanide).

Liver fluke treatment for cattle and sheep
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The importance of a strategic dosing regimen

To maximise their margins, dairy, beef and sheep farmers are continually striving to become ever more efficient in the production of milk and meat. To do this, it is essential that animals are kept in good condition allowing them to thrive and perform optimally.

As farmers continue to become more efficient, so the demand on the animals increase to produce milk or meat and therefore they can be more susceptible to worm burdens, resulting in reduced performance, and ultimately increased cost to the farmer.

Based on recent research by Holzhauer et al (2011), the average cost of an outbreak of lungworm on a dairy cow herd is approximately €160/cow/lactation/year. This was primarily due to reduced milk yields of up to 15 to 20%.

Parasitic Infections

Livestock can accumulate parasitic infestations whilst grazing pastures that contain the infective stages of parasites (larvae and metacercariae). The most recognised parasitic infestations in Ireland are from stomach worms (Ostertagia and Cooperia species), lungworm (Dictyocaulus viviparus or ‘hoose’) and liver fluke (Fasciola hepatica) which are common internal parasites in production livestock. Each of these parasites can be costly to the farmer due to reduced feed intake, lower conversion rates and poor thrive and performance.

Stomach Worms

Parasitic gastroenteritis caused by stomach worms is often the most problematic in Ireland resulting in clinical signs such as diarrhoea and weight loss. Livestock may also have reduced feed intake and conversion.

Lungworms

Also known as ‘hoose’, lungworm can be severe, causing reduced performance in livestock and can sometimes be fatal. Lungworm is primarily seen in younger cattle in their first grazing, but older cattle will be susceptible if immunity was not built up as calves. The lifecycle of the lungworm after ingestion by livestock is approximately 4 weeks. After this period, susceptible cows or calves could be shedding millions of larvae.

Clinical signs of lungworm are coughing, increased respiratory rate, followed by pneumonia in severe cases. Warm, humid conditions combined with rainfall will increase the reproductive cycle of lungworms, meaning faster infestation rates.

Liver Fluke

Hepatica (liver fluke) is seen in livestock of all stages and general symptoms are reduced performance and loss of condition. Similar to lungworms, warm and unseasonably wet conditions are ideal for fluke development. Once ingested, Liver fluke metacercariae take approximately 10-12 weeks to reach maturity and start producing eggs. Therefore, it’s important to dose with flukicides in the autumn, before housing or at housing, with a second follow up treatment eight to 12 weeks after housing.

In some cases, livestock may acquire liver fluke exposure earlier in the grazing season if pastures are heavily infested and weather conditions are optimal for liver fluke reproductive cycle in the mud snail.

Strategies to reduce worm burdens:

  • New or reseeded pastures will generally carry lower numbers of infective larvae;
  • Crop rotation between grasses and cereals/root crops is encouraged if possible;
  • Rotation between pastures can also help reduce worm numbers of infective larvae;
  • Higher stocking rates and tighter grazing rotations can potentially lead to higher worm presence on pastures;
  • Younger stock will also be more susceptible as they haven’t built up immunity and should be kept to a fresh pasture where possible;
  • Permanent pastures that have been grazed by younger stock within the previous six months are more at risk;
  • The highest risk of accumulation later in the grazing season (July onwards);
  • Effective use of anthelminthic products. With resistance to anthelmintics widely recognised it’s essential to rotate anthelminthic products;
  • Allow livestock to build up their immunity.

Patrick Shalvey from Drumgoon, Co. Cavan, runs a family-owned dairy herd and recognises the benefit of Tramazole, stating: “We use Tramazole at drying off using a 60ml, small volume dose and also before calving in February.” To reduce labour, Patrick uses a hook dosing gun which he finds “very handy”. Patrick also doses younger calves six to eight weeks after first grazing with Tramazole and alternates other products to prevent a build-up of resistance. After using it for four to five years on their farm, Patrick mentioned that it’s a “great product” and they’ve been getting “good results”.

Listen to what Patrick says about his dosing regimen

Tramazole

Tramazole 10% contains Albendazole as the active ingredient. It controls both adult fluke and fluke and roundworm eggs, which helps to reduce contamination of pasture.

It’s used to treat and control mature and developing immature forms of gastro-intestinal roundworms, lungworms and adult liver fluke in cattle and sheep, including Ostertagia type II (winter scour) and requires small dosing amounts of 60ml per 600kg cow. Tramazole offers short withdrawal periods of just 60 hours for milk and 14 days for meat. This makes it ideal for dairy cattle. It’s essential that first grazers are regularly dosed because they will have poor immunity and be much more susceptible to worm burdens.

Calves or other livestock that are treated with anthelminthic products claiming long residual effect, maybe much slower to build up their immunity as they will have little or no exposure to worms over the grazing period.

References

1. Holzhauer, M., Van Schaik, G., Saatkamp, H.W. and Ploeger, H.W.,
2011. Lungworm outbreaks in adult dairy cows: estimating economic
losses and lessons to be learned. Veterinary Record.

Our full oral dosing range of products

The importance of a strategic dosing regimen
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The importance of nutritional supplements for farming livestock

Vitamin, mineral and trace elements are a key concern at all stages of farm animals’ life cycle. Trace elements play a vital role in the productivity, fertility and thrive in sheep and both beef and dairy cattle. This can be especially the case as many farmers move to a largely grass-fed diet to improve cost efficiencies because many concentrates are often fortified with trace elements. Some of the key minerals and trace elements that farmers are generally well able to recognise the importance of are copper (Cu), cobalt (CO), selenium (Se) and Iodine (I). Some identifiable signs that livestock may be lacking these key elements are a loss of hair around the eyes and back, discolouration of the coat, ill-thrift, in-fertility, swelling of the joints, scour, poor conversion and growth below their genetic potential.

Listen to what farmers in Ireland say about Growvite

Often, problems could arise when animals are lacking some of these elements but are not showing observable signs and this can result in reduced productivity or conversion rates in both cattle and sheep, ultimately leading to increased costs to the farmer.

‘A Great Boost’

Patrick Shalvey from Drumgoon, Co. Cavan, recognised the benefits of dosing milking cows that aren’t thriving with Growvite Forte, by treating them on an individual basis. He mentioned that “he gives them [milking cows] a shot of Growvite shortly after calving” because it “gives the cows a great boost”. Livestock are also more vulnerable at certain stages of growth or as a result of their specific diets; for example, lambs, calves and ewes or cows that are pregnant or during the lactating cycle. Cattle and sheep on poor quality pasture or grazing at high stocking rates.

 


‘Big Difference’


The Coen family located in Hollymount, Co. Mayo, run a mixed heard of suckler cows and breed both commercial and pedigree Texel ewes. They record performance data of their sheep through the year and recognised that Growvite makes a “big difference”. “After using Growvite Sheep we get a boost in weight and average daily gains in our lambs and it has helped them develop in good condition,” stated the Coen family. Univet’s Growvite range supplies chelated minerals, vitamins and trace elements essential for thriving.

Growvite’s unique blend is ideal for critical stages in the animal’s life cycle when they are growing and developing, such as cows/ewes during gestation or during the lactation cycle. Lambs and calves (>3 weeks) should be dosed with Growvite to improve thrive and performance in growing animals.
Growvite is specially formulated to allow for rapid absorption in the gut and to provide a rapid source of energy. Trial results on sheep conducted by the University of Wales showed that after the application of Growvite, lambs born alive increased by 22%; ewes were in better body condition; and a 50% decrease in barrenness. Trial results are available on request. Growvite can be administered orally, added in milk or be given through feed. It is best to be dosed on a routine basis to ensure livestock are healthy and thriving.

 

Our  full range of Nutritional Supplements

The importance of nutritional supplements for farming livestock
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Growvite All-Ireland Texel Sheep Championship 2017

Univet Ltd., a family owned business based in County Cavan have been the main sponsor of the Growvite All-Ireland Texel Sheep Championship for a number of consecutive years. The most recent championship took place at the sun-drenched Gorey Agricultural Show on 17th June 2017.

Supreme Champion was awarded to a Ram Lamb UVI1701309 sired by Tophill Wallstreet and a Strathbogie Python ewe, bred and owned by John Neville, Thornville Texels.

Supreme Champion UVI1701309, bred and owned by John Neville, Thornville Texels.

Reserve Supreme Champion was awarded to the winner of the Senior Ewe Lamb Class and the Female Championship winner DII1701294 out of Knock Yazoo and a Derrylahan bred sired Garngour Vintage ewe shown by Anthony Donnelly from Claremorris in Co. Mayo.

Univet wish to congratulate all the winners on the day and in particular the Supreme Champion UVI1701309 and Reserve Supreme Champion DII1701294. Univet produce a number of products for sheep including Growvite Sheep, Growvite Multibirth and Growvite Lamb in addition to a number of anthelmintics. Curafluke 5% Oral Drench permits a three way activity against fluke, lungworm and stomach worm and Curazole 5% can be used for the control of mature and immature forms of roundworms and lungworms. Growvite Sheep is a complementary feeding stuff providing chealated minerals, vitamins and trace elements essential for improved fertility in sheep and improved thrive in lambs and ewes. Univet produce a diverse range of products for cattle, sheep and pigs, including sterile injections, intramammaries, anthelmintics, oral powders and premixes and nutritional supplements.

Growvite All-Ireland Texel Sheep Championship 2017
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