With the turnout of youngstock, attention turns to how best to control for parasites in first grazing season (FGS) calves, which are most vulnerable to parasites due to their lack of previous exposure.
The main parasites to consider now will be roundworms causing parasitic gastroenteritis, and Dictyocaulus lungworm.
Vaccination is the most effective form of control for lungworm and should be done before turnout.
Prior to turnout, assess the risk posed by lungworm and roundworm on the pasture to be grazed.
FGS calves should ideally go onto “low-risk” pasture that has not been grazed by calves or youngstock in the previous grazing season. FGS calves going onto contaminated pasture may need a strategic anthelmintic dose two to three weeks after turnout.
Calves going onto lower-risk pastures should be monitored with faecal worm egg counts (FWEC) for roundworms and lungworm.
These tests are recommended at regular intervals throughout the grazing season.
Weighing to monitor average daily liveweight gain (ADLWG) is also an effective monitoring tool for roundworm status in youngstock and we should be targeting ADLWG of greater than 0.7kg/day at grass.
Wormer treatments should be targeted based on discussion with your vet.
As an example, presence of lungworm larvae, a group average FWEC over 200 eggs per gram and/or failure to achieve ADLWG of greater than 0.6kg/day may indicate the need for potential wormer treatment for roundworm and lungworm.
There is a huge emphasis on preventing resistance build up to the wormer products by the worms and reducing the amount of dosing we do will help with this.
FWEC counts often show that a dose is not needed and so time, labour, money and wormer resistance is saved by not dosing needlessly.
Craig McAlister MRCVS, Parklands Veterinary Group, Northern Ireland
SHARING OPTIONS