An attempt to control lungworm disease and parasitic gastroenteritis on commercial dairy farms by the use of an adaptation of Michel's dose-and-move system

On seven dairy farms an attempt was made to control lungworm disease in calves by turnout on a pasture grazed earlier by cows, followed by a move to aftermath and ivermetcin treatment 2 months later. Transmission of lungworm was observed on all farms. Lungworm disease occurred on four farms at treatment. Coughine re-occurred on three of these farms in some animals 2 months later. Owing to poor performance between turnout and treatment, weight gain was below the norm on the farm with the highest infections and most severe respiratory signs. On the other farms respiratory signs did not result in poor weight gain. Gastrointestinal nematode infections remained low on all farms. The conclusion is that this dose and move schemes cannot be recommended for the control of lungworm.