Management of parasites in beef and dairy cattle around housing
- What are the treatment options for Ostertagia Type II?
- How can I reduce the risk of resistance?
- What other parasite treatments may be required around housing?
The main parasites of concern around housing are those that could have been picked up over the grazing season: gut worms (including Ostertagia); liver fluke; and potentially lungworm. Treatment may also need to cover external parasites of cattle such as lice and mange if they are a concern within the group.
As discussed in ‘Protecting your beef herd from Type II Ostertagia’, anthelmintic treatment may be needed to control Type II Ostertagia, either through a ‘housing dose’ or for treatment of clinically sick animals. This means that cattle should be assessed at housing for any signs of worm burden, and a faecal worm egg count (FWEC) should be undertaken on pooled muck samples. Results should be discussed with your farm vet to determine if treatment is necessary.
What are the treatment options for Ostertagia Type II?
If a ‘housing dose’ is needed it is important to use a classof wormer that is effective at killing both adults and larval stages ofOstertagia. Yellow drenches are not suitable for a housing dose (or totreat Type II Ostertagia cases) as they do not kill larval stages.
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How can I reduce the risk of resistance?
As always, it is vital to ensure that any anthelmintic treatment is given correctly, as inadequate treatment is both ineffective and will increase the risk of anthelmintic resistance within the herd.
Tips to maximise treatment success include:
• Weigh the animals to ensure an accurate dose is given
• Calibrate the treatment gun before use to make sure it is giving the correct dose
• If using a pour on, ensure that cattle are not exposed to rain immediately after dosing
• Store wormers suitably so they do not lose their effectiveness (e.g. leaving a wormer out in freezing weather is likely to significantly reduce its efficacy)
• Ensure wormers are used within their use-by date and once open, discard them as per the instructions on the packaging
• Do a post-treatment check on pooled muck samples to ensure the product was effective
More details can be found on the COWS website – www.cattleparasites.org.uk.
What other parasite treatments may be required around housing?
Lungworm and gut worms will have been treated if needed with anthelmintic treatment described above. Ectoparasites such as lice and mange will be covered in next month’s blog but can be treated by Group 3 products (see table above). However, liver fluke is generally not covered by anthelmintic treatments.
Liver fluke is a parasite that is picked up from grazing wet or boggy areas; immature liver fluke migrate through the body and mature over around 12 weeks, with adult fluke living inside the liver. Both adults and immature stages can cause disease. Liver fluke will be discussed in more detail in the December dairy article.
If the cattle have been grazing a high-risk area for liver fluke then it is worth screening the group or herd for the disease around the time of housing. In autumn we can test for the presence of immature fluke using the copro-antigen test, while later in winter or early spring we can test for the presence of adult fluke by looking for fluke eggs. Both can be done using pooled muck samples from a group of cattle.
If clinical signs and/or test results show that the group is at high risk for fluke then the group would benefit from treatment around housing. Which product to use will depend on the level of fluke risk and the time of housing. Triclabendazole products will kill adults and immature fluke down to 2 weeks, but there is a high risk of resistance developing to these products if they are overused. Triclabendazole resistance was discovered in Scotland as far back as 1998 and is now present in farms across the UK.1
If housing treatment for either worms or fluke is required then this should be discussed with your vet or SQP who can help you assess the risks and recommend appropriate product(s). Chanelle has put together a Housing Treatment Guide which can be used in conjunction with veterinary advice to provide a treatment plan.
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References:
1. Fairweather I, Brennan GP, Hanna REB, Robinson MW, Skuce PJ. Drug resistance in liver flukes. Int J Parasitol Drugs Drug Resist. 2020 Apr;12:39-59.
Management of parasites in beef and dairy cattle around housing
- What are the treatment options for Ostertagia Type II?
- How can I reduce the risk of resistance?
- What other parasite treatments may be required around housing?
The main parasites of concern around housing are those that could have been picked up over the grazing season: gut worms (including Ostertagia); liver fluke; and potentially lungworm. Treatment may also need to cover external parasites of cattle such as lice and mange if they are a concern within the group.
As discussed in ‘Protecting your beef herd from Type II Ostertagia’, anthelmintic treatment may be needed to control Type II Ostertagia, either through a ‘housing dose’ or for treatment of clinically sick animals. This means that cattle should be assessed at housing for any signs of worm burden, and a faecal worm egg count (FWEC) should be undertaken on pooled muck samples. Results should be discussed with your farm vet to determine if treatment is necessary.
What are the treatment options for Ostertagia Type II?
If a ‘housing dose’ is needed it is important to use a classof wormer that is effective at killing both adults and larval stages ofOstertagia. Yellow drenches are not suitable for a housing dose (or totreat Type II Ostertagia cases) as they do not kill larval stages.
How can I reduce the risk of resistance?
As always, it is vital to ensure that any anthelmintic treatment is given correctly, as inadequate treatment is both ineffective and will increase the risk of anthelmintic resistance within the herd.
Tips to maximise treatment success include:
• Weigh the animals to ensure an accurate dose is given
• Calibrate the treatment gun before use to make sure it is giving the correct dose
• If using a pour on, ensure that cattle are not exposed to rain immediately after dosing
• Store wormers suitably so they do not lose their effectiveness (e.g. leaving a wormer out in freezing weather is likely to significantly reduce its efficacy)
• Ensure wormers are used within their use-by date and once open, discard them as per the instructions on the packaging
• Do a post-treatment check on pooled muck samples to ensure the product was effective
More details can be found on the COWS website – www.cattleparasites.org.uk.
What other parasite treatments may be required around housing?
Lungworm and gut worms will have been treated if needed with anthelmintic treatment described above. Ectoparasites such as lice and mange will be covered in next month’s blog but can be treated by Group 3 products (see table above). However, liver fluke is generally not covered by anthelmintic treatments.
Liver fluke is a parasite that is picked up from grazing wet or boggy areas; immature liver fluke migrate through the body and mature over around 12 weeks, with adult fluke living inside the liver. Both adults and immature stages can cause disease. Liver fluke will be discussed in more detail in the December dairy article.
If the cattle have been grazing a high-risk area for liver fluke then it is worth screening the group or herd for the disease around the time of housing. In autumn we can test for the presence of immature fluke using the copro-antigen test, while later in winter or early spring we can test for the presence of adult fluke by looking for fluke eggs. Both can be done using pooled muck samples from a group of cattle.
If clinical signs and/or test results show that the group is at high risk for fluke then the group would benefit from treatment around housing. Which product to use will depend on the level of fluke risk and the time of housing. Triclabendazole products will kill adults and immature fluke down to 2 weeks, but there is a high risk of resistance developing to these products if they are overused. Triclabendazole resistance was discovered in Scotland as far back as 1998 and is now present in farms across the UK.1
If housing treatment for either worms or fluke is required then this should be discussed with your vet or SQP who can help you assess the risks and recommend appropriate product(s). Chanelle has put together a Housing Treatment Guide which can be used in conjunction with veterinary advice to provide a treatment plan.
References:
1. Fairweather I, Brennan GP, Hanna REB, Robinson MW, Skuce PJ. Drug resistance in liver flukes. Int J Parasitol Drugs Drug Resist. 2020 Apr;12:39-59.