Homepage / Current / Summer is a good time to use faecal egg counts (FECs) to monitor gut worm infection in first and second season grazing calves. Assess condition and weight gain and provided nutritional needs are being met, consider further investigation of calves are failing to thrive. If FECs come back positive, but below the 200 eggs/gram threshold for treating, test again in two to three weeks, as FECs can rise quickly in July and August