Dr Forbes says the reasons why much of what we know about anthelmintic resistance is based on the parasites of sheep are that sheep of all ages, not just lambs, are often treated with anthelmintics regularly and so the selection pressure for resistance is quite high each year.
In addition," he says, "the consequences of treatment failure due to anthelmintic resistance can be severe; in regions where the bloodsucking stomach worm, Haemonchus contortus, predominates, deaths through anaemia can be seen in both ewes and lambs."
Dr Forbes says "it is pivotal in the control of parasites that farmers and vets know which parasites are present, what impact they are
making and how well they are being controlled."
Samples and tests
In addition to monitoring clinical signs and performance, particularly growth rates at pasture, there are a number of samples and tests that can be performed to get more precise diagnoses.
A common test involves collecting fresh dung samples and examining them for worm eggs or larvae.
"This can not only tell you which parasites are present, but can also be used to assess the efficacy of wormer treatments," says Dr Forbes.
In summary, the key elements of managing anthelmintic resistance can be reduced to three simple things to remember and do: the ABC of responsible anthelmintic use:
Accurate dosing - weigh scale or weigh band to use on each animalCalibrate dosing equipment before each use - beware of high frequency (every 4 weeks) worm treatments over long periods (6 months or more)Read the full article here.
Dr Forbes says the reasons why much of what we know about anthelmintic resistance is based on the parasites of sheep are that sheep of all ages, not just lambs, are often treated with anthelmintics regularly and so the selection pressure for resistance is quite high each year.
In addition," he says, "the consequences of treatment failure due to anthelmintic resistance can be severe; in regions where the bloodsucking stomach worm, Haemonchus contortus, predominates, deaths through anaemia can be seen in both ewes and lambs."
Dr Forbes says "it is pivotal in the control of parasites that farmers and vets know which parasites are present, what impact they are
making and how well they are being controlled."
Samples and tests
In addition to monitoring clinical signs and performance, particularly growth rates at pasture, there are a number of samples and tests that can be performed to get more precise diagnoses.
A common test involves collecting fresh dung samples and examining them for worm eggs or larvae.
"This can not only tell you which parasites are present, but can also be used to assess the efficacy of wormer treatments," says Dr Forbes.
In summary, the key elements of managing anthelmintic resistance can be reduced to three simple things to remember and do: the ABC of responsible anthelmintic use:
Accurate dosing - weigh scale or weigh band to use on each animalCalibrate dosing equipment before each use - beware of high frequency (every 4 weeks) worm treatments over long periods (6 months or more)Read the full article here.
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