A growing number of sheep farmers in NI are going back to using plunge-dipping for the control of external parasites in their flocks, reports from local farmers and agricultural suppliers indicate.
The change in approach to ectoparasite control mainly stems from the increased prevalence of sheep scab seen in NI flocks in recent years. Scab is caused by a mite and can lead to wool loss, reduced animal performance and welfare issues in sheep.
Plunge-dipping is the most effective method of controlling the issue in flocks.
However, over the past 25 years many farmers moved away from plunge-dipping due to the end of compulsory dipping in the UK in 1992, stricter regulations surrounding the disposal of sheep dip and the need to hold a certificate of competence to be able to buy dip.
Other factors include fewer dip products being available on the market and the significant physical labour requirement for plunge-dipping. Farmers subsequently started using injectable products, mobile dipping units and pour-on products to control external parasites.
Showers
However, questions around the effectiveness of mobile showers, jetters and sprayers for controlling scab mean that there are no sheep dip products available in NI which are licensed for use in these units.
The concern is that they give a limited coverage of dip on sheep, meaning mites can remain in certain areas, such as under the legs and in the ears, and develop resistance to the dip.
While mobile showers, jetters and sprayers could be used to control other external parasites, their ineffectiveness against scab led to the recent UK-wide ban on the use of organophosphate-based (OP) dips in these units.
Eoin's mobile dipper has a throughput of around 150 sheep per hour.
This decision was taken to stop mites developing resistance to OP-based dips, and to ensure that the products remain effective in plunge-dippers (where there is full coverage of dip on sheep).
The only sheep dip product currently available in agricultural suppliers in NI is Gold Fleece, an OP-based product manufactured by Bimeda.
Owners of showers, jetters and sprayers that ignore the ban and use Gold Fleece or OP-based products from the Republic of Ireland, such as Ectoflits or Hygeia’s summer or winter dips, are increasing the risk of mites developing resistance to these products.
Other options
With pour-ons, there is no product available which is effective for the control of sheep scab. It should also be noted that not all pour-on products are effective against all other external parasites, such as blowfly (prevention and treatment can differ), lice and tick.
Injectable avermectin-based products, such as Dectomax, are effective for the control of scab. While there have been some cases of resistance reported recently when injectables were used, persistence is the main issue as sheep can be easily re-infected with mites.
Avermectin products are classified as group three (clear coloured) wormers and they can also control internal parasites, such as roundworms and lungworms. However, using these products for the control of scab when there is a low burden of internal parasites in sheep can lead to resistance issues.
Eoin Kelly and his mobile plunge-dipping unit.
So more farmers are moving back to plunge-dipping as it allows control of scab with no risk of resistance issues. Persistence is less of a problem with plunge-dipping compared with injectables, as OP-based dips remain active on the sheep for longer than the 17-day period where mites can survive in the environment without a host. Plunge-dipping also controls blowfly (treatment and prevention), lice and ticks.
Requirements for starting to plunge-dip
There are two key requirements for a farmer to start plunge-dipping sheep in NI. Both are legal requirements which are also checked during farm quality assurance inspections.
Firstly, a certificate of competence in the safe use of sheep dip is needed to allow the farmer to buy dip from a licensed supplier. This involves a full day training course with a two-hour long assessment carried out on a different day.
Course fees generally start from £150 plus VAT and the certificate is a lifetime qualification, which means follow-up training is not necessary.
The other requirement is authorisation from the NI Environment Agency (NIEA) to dispose of leftover sheep dip. The necessary form is available on the DAERA website and it has to be printed, completed and posted to NIEA along with a farm map.
Mobile plunge-dipping service starts in NI
The growing popularity of sheep dipping, coupled with regulations surrounding the purchase of dip, has created a market for contractors with mobile plunge-dippers.
Several mobile plunge-dipping contractors are available in the Republic of Ireland and a local farmer from Draperstown, Co Derry, has launched a similar service in NI in recent weeks.
Eoin Kelly’s mobile dipper holds 1,100l of mixed dip and has a throughput of around 150 sheep/hour. The dipper is towed behind a pickup and folds down with two shoots for sheep to walk on and off the unit.
A pen holds a ewe at the front of the inward shoot to encourage sheep to move up the race.
At the top of the shoot is a sloped floor, which makes it easy for the sheep to fall through a curtain into the bath.
The bath holds 1,100l of mixed dip and the draining pen can take 28 sheep on average.
Sheep are then dipped by Eoin and a ramp at the far end allows them to walk out to access a draining pen, which holds up to 28 sheep.
The mobile unit needs to be filled when Eoin arrives on the farm, although he can transport around 500l of dip if a move to a different yard on the same farm is required.
Eoin charges £1/head for the service, which includes the cost of the Gold Fleece dip, although lower rates are available for larger flocks.
He said the service removes the need for the farmer to have a certificate of competence and it involves less physical labour than most stationary concrete dippers.
However, the farmer still needs an approved way of disposing of the leftover dip.
Read more
Industry support for sheep scab eradication
Getting on top of flies and ticks in your flock
Sheep management: blowfly options, dispatch documents and lamb castrations
A growing number of sheep farmers in NI are going back to using plunge-dipping for the control of external parasites in their flocks, reports from local farmers and agricultural suppliers indicate.
The change in approach to ectoparasite control mainly stems from the increased prevalence of sheep scab seen in NI flocks in recent years. Scab is caused by a mite and can lead to wool loss, reduced animal performance and welfare issues in sheep.
Plunge-dipping is the most effective method of controlling the issue in flocks.
However, over the past 25 years many farmers moved away from plunge-dipping due to the end of compulsory dipping in the UK in 1992, stricter regulations surrounding the disposal of sheep dip and the need to hold a certificate of competence to be able to buy dip.
Other factors include fewer dip products being available on the market and the significant physical labour requirement for plunge-dipping. Farmers subsequently started using injectable products, mobile dipping units and pour-on products to control external parasites.
Showers
However, questions around the effectiveness of mobile showers, jetters and sprayers for controlling scab mean that there are no sheep dip products available in NI which are licensed for use in these units.
The concern is that they give a limited coverage of dip on sheep, meaning mites can remain in certain areas, such as under the legs and in the ears, and develop resistance to the dip.
While mobile showers, jetters and sprayers could be used to control other external parasites, their ineffectiveness against scab led to the recent UK-wide ban on the use of organophosphate-based (OP) dips in these units.
Eoin's mobile dipper has a throughput of around 150 sheep per hour.
This decision was taken to stop mites developing resistance to OP-based dips, and to ensure that the products remain effective in plunge-dippers (where there is full coverage of dip on sheep).
The only sheep dip product currently available in agricultural suppliers in NI is Gold Fleece, an OP-based product manufactured by Bimeda.
Owners of showers, jetters and sprayers that ignore the ban and use Gold Fleece or OP-based products from the Republic of Ireland, such as Ectoflits or Hygeia’s summer or winter dips, are increasing the risk of mites developing resistance to these products.
Other options
With pour-ons, there is no product available which is effective for the control of sheep scab. It should also be noted that not all pour-on products are effective against all other external parasites, such as blowfly (prevention and treatment can differ), lice and tick.
Injectable avermectin-based products, such as Dectomax, are effective for the control of scab. While there have been some cases of resistance reported recently when injectables were used, persistence is the main issue as sheep can be easily re-infected with mites.
Avermectin products are classified as group three (clear coloured) wormers and they can also control internal parasites, such as roundworms and lungworms. However, using these products for the control of scab when there is a low burden of internal parasites in sheep can lead to resistance issues.
Eoin Kelly and his mobile plunge-dipping unit.
So more farmers are moving back to plunge-dipping as it allows control of scab with no risk of resistance issues. Persistence is less of a problem with plunge-dipping compared with injectables, as OP-based dips remain active on the sheep for longer than the 17-day period where mites can survive in the environment without a host. Plunge-dipping also controls blowfly (treatment and prevention), lice and ticks.
Requirements for starting to plunge-dip
There are two key requirements for a farmer to start plunge-dipping sheep in NI. Both are legal requirements which are also checked during farm quality assurance inspections.
Firstly, a certificate of competence in the safe use of sheep dip is needed to allow the farmer to buy dip from a licensed supplier. This involves a full day training course with a two-hour long assessment carried out on a different day.
Course fees generally start from £150 plus VAT and the certificate is a lifetime qualification, which means follow-up training is not necessary.
The other requirement is authorisation from the NI Environment Agency (NIEA) to dispose of leftover sheep dip. The necessary form is available on the DAERA website and it has to be printed, completed and posted to NIEA along with a farm map.
Mobile plunge-dipping service starts in NI
The growing popularity of sheep dipping, coupled with regulations surrounding the purchase of dip, has created a market for contractors with mobile plunge-dippers.
Several mobile plunge-dipping contractors are available in the Republic of Ireland and a local farmer from Draperstown, Co Derry, has launched a similar service in NI in recent weeks.
Eoin Kelly’s mobile dipper holds 1,100l of mixed dip and has a throughput of around 150 sheep/hour. The dipper is towed behind a pickup and folds down with two shoots for sheep to walk on and off the unit.
A pen holds a ewe at the front of the inward shoot to encourage sheep to move up the race.
At the top of the shoot is a sloped floor, which makes it easy for the sheep to fall through a curtain into the bath.
The bath holds 1,100l of mixed dip and the draining pen can take 28 sheep on average.
Sheep are then dipped by Eoin and a ramp at the far end allows them to walk out to access a draining pen, which holds up to 28 sheep.
The mobile unit needs to be filled when Eoin arrives on the farm, although he can transport around 500l of dip if a move to a different yard on the same farm is required.
Eoin charges £1/head for the service, which includes the cost of the Gold Fleece dip, although lower rates are available for larger flocks.
He said the service removes the need for the farmer to have a certificate of competence and it involves less physical labour than most stationary concrete dippers.
However, the farmer still needs an approved way of disposing of the leftover dip.
Read more
Industry support for sheep scab eradication
Getting on top of flies and ticks in your flock
Sheep management: blowfly options, dispatch documents and lamb castrations
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