Control is key to helping your animals thrive

Q&A: parasite control
Control is key to helping your animals thrive

Herd health planning with your vet and Teagasc adviser facilitates the prevention of clinical cases of gutworm, lungworm, and fluke, and helps increase production and reduce subclinical losses, according to the presentation last week by Frank O’Sullivan, of Veterinary Ireland, and of the Patrick Farrelly and Partners veterinary practice in Trim, Co Meath.

Monitoring faeces in the laboratory and collection and communication of inspection results (CCIR) from the abattoir assists in key decisions.

For Irish suckler and beef farmers the most important internal parasites to combat during the grazing season are stomach and intestinal worms (known as gut worms), lungworms (causing hoose pneumonia), and liver and rumen fluke.

Because infections with parasites can build up over the grazing season, the period of greatest risk is the second half of the season (until housing).

Control prevents animals from dying (from acute hoose pneumonia or heavy fluke infestation, for example), and perhaps more importantly, reduces ill-thrift and helps animals thrive.

Let us take a typical 50-cow suckler farm, grazing mainly on old pasture with calves at foot. This farm also fattens all stock to beef. In addition, they buy 30 weanlings in October every year to increase their beef numbers. In mid-September, just after weaning, the suckler calves are scouring and not thriving as well as expected. They are grazing with the cows on permanent pasture and have not been dosed yet. What could be the problem?

There are a number of possibilities.

Gutworms are high on the list.

By mid-June, worm eggs, even from the cows, will have hatched and developed into infective larvae (several cycles may have occurred) which, with moisture and rain, will have moved from dung pats onto the pasture.

Close grazing will also increase the larva intake by the calves.

The condition is called parasitic gastroenteritis.

Faecal testing 10 to 15 samples (which may be pooled in the laboratory) will aid the diagnosis.

Your veterinarian will likely also consider secondary copper deficiency and coccidiosis as part of the possible diagnoses.

Be careful that lungworm levels may also be at critical levels.

If necessary, an appropriate anthelmintic will deal with this problem.

It is also possible to check the faecal egg counts after dosing, to ensure there is no resistance to the anthelmintic used.

Also, second-year grazers need to be monitored.

In our suckler farm described above, after housing in November, all the weanlings (both home-reared and bought-in) are coughing persistently. What is causing this?

This is a tricky situation in that both virus pneumonia and lungworm are high on the list of differential diagnoses. Clinical examination plus laboratory testing will help the vet decide where the problem and solution lie. Both diseases could be interacting.

The bought-in weanlings are challenging the biosecurity on the farm and possibly introducing viruses that are causing pneumonia.

Extended grazing may also have increased the season for lungworm so this may also need attention.

A herd health programme with your veterinarian would likely prevent many of these diseases and keep thrive going well.

Three cull cows are fattened for slaughter and the factory report live fluke in their livers. What does this mean?

CCIR from the abattoir in this case has provided direct evidence that your cows are infected with fluke.

It would be appropriate to faecal test other groups of stock and, with your veterinarian, put a fluke management program in place.

This may include:

* Drainage or fencing off wet areas and avoidance of poaching;

* Strategic dosing in early summer to reduce the number of snails becoming infected;

* Dose and quarantine bought-in animals;

* Monitor fluke burdens both by faecal testing and from the abattoir liver reports;

* Faecal sampling at an appropriate time after dosing with a flukacide will assist in the assessment of resistance;

* Appropriate treatment of affected groups with a flukacide.

Parasite control

Because infections with parasites can build up over grazing season, the period of greatest risk is the second half of the season

More in this section


Keep up-to-date with all the latest developments in Farming with our weekly newsletter

Sign up

Our Covid-free newsletter brings together some of the best bits from, as chosen by our editor, direct to your inbox every Monday.

Sign up