FG BUY&SELL        FARMERS WEATHER       ARABLE FARMING        DAIRY FARMER      FARMERS GUARDIAN        AGRIMONEY        OUR EVENTS        MEMBERSHIP BENEFITS        BLOGS        MORE FROM US

You are viewing 1 of your 2 free articles

You’ll need to join us by becoming a member to gain more access.
Already a Member?

Login Join us now

Vet's View: The impact of Border disease on performance

Insights

Border disease is caused by a pestivirus related to bovine viral diarrhoea (BVD) virus, explains Mrs Batty.

Twitter Facebook

It can be the cause of poor scanning percentages or poorer lambing percentages than normal, more abortions and stillbirths, weakly lambs, ‘hairy shakers’ and increased incidence of lamb diseases, she says.

 

“It is transmitted mainly by nose to nose contact and is most commonly introduced into a flock by a bought-in infected animal. Cattle can spread BVD virus to sheep and less commonly sheep can pass Border disease to cattle.”

 

“A SAC/Moredun study in 2006 found a third of the 125 Scottish flocks tested had evidence of exposure to Border disease,” says Mrs Batty.

 

Adult and healthy lambs exposed to Border disease show only mild signs or no clinical signs at all. Serious consequences occur when sheep are exposed during pregnancy, she explains.

Clinical signs

“Clinical signs include an increase in the number of barren ewes, abortions, still births and the birth of small weakly lambs.

 

“In some cases lambs may be born with skeletal deformities, tremors and hairy fleeces, known as hairy shakers - don’t assume that all deformed and dummy lambs are due to Schmallenberg virus infection,” says Mrs Batty.

 

“If the pregnant ewe is infected before the foetus has the ability to mount an antibody response [around 85 days], the lamb will become persistently infected with virus.

 

“These lambs are often referred to as ‘PI’s’, and may appear normal at birth, be weak or have a body tremor.”

 

Mrs Batty explains the term ‘hairy shakers’ comes from the long fibres sometime seen in the lamb’s wool.

 

Many of the PI lambs die early in life, however some apparently healthy looking lambs will survive and act as a source of infection to the rest of the flock, she adds.

 

“If you suspect Border disease in your flock, the first person to speak to is your vet. They can advice you on the most appropriate method of investigation.

 

“A diagnosis of suspect Border disease can be made based on clinical examination of a number of hairy shaker lambs.

 

“Diagnosis can be confirmed by blood sampling affected lambs for Border disease virus or by submitting dead lambs to your local AHVLA or SAC consulting veterinary disease surveillance centre.”

 

But Mrs Batty warns not all flocks will present with the classical signs.

 

“Border disease can go undiagnosed as there are numerous causes of increased abortion and barren rates.

 

“A barren rate of more than 5 per cent at scanning and an abortion rate of over 2 per cent or a number of abortions over consecutive days should be investigated,” she advises.

Blood samples

“Aborted or barren ewes can be blood sampled for the Border disease antibody and virus as part of an abortion enquiry.”

 

The flock’s status can be assessed by screening around 10 hoggs or gimmers aged six to 18 months, again for the Border disease antibody, adds Mrs Batty.

 

She says: “If you have a number of separate groups which don’t mix, then ten animals from each group should be tested.

 

“If the screen shows evidence of exposure to Border disease virus, then screening to look for the source or sources of infection should be considered by virus testing individual sheep to identify the persistently infected animal.

 

“As part of the quarantine procedure consideration should be given to blood sampling replacements for Border disease virus.”

 

Border disease

  • Investigate increased barren and abortion rates
  • Do not assume all deformed and dummy lambs are due to Schmallenberg virus
  • Screen your flock for Border disease antibody to see if it has been exposed
  • Consider testing replacements for Border disease virus
Twitter Facebook
Rating (0 vote/s)
Post a Comment
To see comments and join in the conversation please log in.

More Insights

Glasto’s robotic rotary starts quiet revolution

Just over a year ago, John Taylor read about the world’s only robotic rotary milking parlour. Today the former Gold Cup winning herd he manages is milked through the first installation in the UK. Ann Hardy reports.

Low cost system ensures profitability

A Gloucestershire dairy farmer relies on a low-cost system which treats the herd as if it were one cow, in order to maintain a profitable business. Wendy Short reports.

Prevent milk fever by testing calcium levels

Data collected by James Husband of Evidence Based Veterinary Consultancy (EBVC) Penrith, from 15 dairy farms, found more than half of cows had low calcium levels post-calving.

Getting sand bedding right

Sand is only one option available for bedding dairy cubicles, posing its own challenges and benefits. Laura Bowyer visited Richard Chewter at a quarry in Hampshire.

Making better use of grass and improving fertility are keys to survival

Ireland’s dairy industry has made substantial improvement in on-farm performance and national output over the past 10 years. Ann Hardy reports from the Ireland Genetics UK Dairy Conference. 
FG Insight and FGInsight.com are trademarks of Briefing Media Ltd.
Farmers Guardian and FarmersGuardian.com are trademarks of Farmers Guardian Ltd, a subsidiary of Briefing Media Ltd.
All material published on FGInsight.com and FarmersGuardian.com is copyrighted © 2016 by Briefing Media Limited. All rights reserved.
RSS news feeds