Dairy calves much more susceptible to stomach worms

Photo O'Gorman Photography.
Photo O’Gorman Photography.

July is the month when dosing will begin for many spring-born calves.

According to Teagasc dairy-born calves will be much more susceptible to stomach worms than suckler calves because there is a dilution effect from the cow and they are less reliant on grass in their diet at this stage in their life.

Teagasc also note that lungworm is the other and probably more significant issue that will have to be dealt with once calves begin coughing.

It says there are a few things that farmers need to bear in mind. Firstly, for stomach worms, taking dung samples to assess whether to dose or not will tell you what the worm burden is like in the calves, and will help us to avoid overdosing. Pooling samples from 10-15 calves will be worth doing.

Secondly, Grange research has shown over the last two years that there is drug resistance building among worm populations. Teagasc highlights that the simplest way to try and prevent resistance building on your farm is to alter the type of product you use. It says if you plan to use a levamisole now, switch to an avermectin or a white dose for the next dose but keep alternating. Your vet will advise you on the differences between the various drug groups.


According to Teagasc, full immunity to blackleg using the clostridial vaccines requires a two shot programme with a booster given four weeks after the primary shot. Avoid giving any other vaccine within 14 days of giving the blackleg vaccine. Where an incidence of blackleg has occurred on a farm, a blackleg vaccination programme is a must.

Summer mastitis

Teagasc is also keen to point out that it is the time of year again when dry cows are going to be susceptible to summer mastitis.

This condition is one where prevention is key. Whether you choose to use dry cow tubes, Stockholm tar or fly repellent to help reduce the risk, it is important to take some combination of preventative measures.

Teagasc advise that cows need to be herded regularly during this high-risk period if you are to spot potential problems. If cows are lying, go in and get them up and walkthrough them. Have cows in well-topped fields and avoid fields that are wet or have a lot of tree cover where fly populations are high.