Farm Ireland
Independent.ie

Sunday 28 May 2017

Halt Virus pneumonia in tracks

Start by putting a Herd Health Plan in place to help eradicate this illness from your herd, writes Peadar ó Scanaill, and be aware of the tell-tale signs in young calves to reduce the disease

Peadar O Scanaill

Virus pneumonia will always be a plague on Irish farms. Young calves, particularly those wintering indoors, are always vulnerable. And yet there is a lot we can do to reduce the damage. A few quick pointers can prevent death from virus pneumonia.

History

In years gone by, we had very few of the nasty forms of infectious pneumonia on this island. However, with the removal of quarantine and the free movement of cattle from mainland Europe directly onto Irish farms, all that has changed. We now see the severe form of IBR and the nasty 'mycoplasma' bacteria. We must now expect these diseases and plan to prevent them grabbing a foothold on our farms -- and there's no better place to start than with your vet and a Herd Health Plan.

This relies on test results from previous years on your farm, and putting a vaccination programme in place.

PNEUMONIA IN CALVES



  • Virus
  • Infectious bovine


rhinotracheitis



  • Rhinosyncitheal virus


(RSV)



  • Para influenza virus (PI3)
  • Bacteria
  • Mycoplasma
  • Pasteurella
  • Various secondary bacteria
  • BVD
  • Immuno-suppression


We will concentrate on virus pneumonia in this article as it is the primary cause of lung disease in calves.

WHAT TO DO WITH A COUGHING CALF

Once a virus gets into the airways of a calf, it spreads quickly among the entire group. It also weakens the calves' immunity and allows in any number of secondary bacteria. Very quickly, we see dead calves.

Once a cough is noticed in a batch, take careful note of the feeding activity of each animal. Note the breathing and call for expert help once any factor becomes a concern. Vaccines are available in live form giving a quick immunity once administered.

However, pedigree herd owners especially must consult their vet when vaccinating against IBR.

Treatment with antibiotics

Antibiotics are completely ineffective against viruses. Their role relies completely on their ability to kill any bacteria that might enter after a virus.

Calf rearing in Ireland must change its habits and break away from the famous "shot of antibiotic". The use of antibiotics to treat pneumonia on Irish farms can be measured in tonnes -- a frightening concept. As vets, we would dearly like to see vaccines being used by the tonne and antibiotics relegated to minimal use.

What does help is fresh air -- and plenty of it. Ventilation of calf sheds is important on any farm, but avoid draughts at body level. See if it is possible to give access to an open area during the day to help dilute the stale, virus-infected air. Always avoid the housing of older stock in the same air space as young calves.

When virus pneumonia strikes, try to separate the sick from healthy calves. This is often not possible, but definitely keep the very young away from an older batch with an infective outbreak. Keep the pens airy and dry with an extensive dry-lying area available at all times. Again, do the 'Sunday Mass' test. See if you can kneel in the bedding area with your Sunday-best trousers on. Can you then go to Mass without two patches on your knees? If not, then the calves are lying on a wet bed.

Investigation

Swabs taken from the sinus or nasal passages of the calf by your vet are the best way to find what bug is causing the cough.

Another option is to take blood samples from a previous batch that was in the same shed. Assuming they also contracted the virus, this allows the laboratory to check what antibodies the older batch have. It can be a good indicator as to what bug is on the farm.

With a severe outbreak we have no options but to resort to antibiotic cover. It is sensible to use some anti-inflammatories too, following along the lines of ourselves and paracetamol when we have flu. And again, to draw parallels, when we have flu, we just want to be left alone and rest until we are better. Calves are similar, and if stocking density is too high, then the sick calf is quickly bullied. We often forget about bullying, but one quick solution is to isolate the worst-affected calf. This gives it a chance to recover and may lessen the spread of the virus.

Indo Farming