Dead lambs © Tim Scrivener

Sheep farmers should consider subsidised post-mortem services more often when faced with fallen stock on farm to save time and money on farm.

Specialist Apha (Animal and Plant Health Agency) and SAC (Scottish Agricultural College) surveillance centres are better equipped than farm vets to deliver post-mortem examinations (PME), a meeting of sheep farmers heard last week.

Furthermore, increasing pressure to reduce antibiotic use and address the growing wormer resistance problem is further reason to use veterinary investigation (VI) centres.

See also: Apha offers free postmortem collection service

Veterinary surgeons Leanne Forde and Rosie Lyle, Bishopton Vets, North Yorkshire, are urging farmers to analyse flock mortality and follow vet advice when PMEs are suggested.

They both spent six months working at Thirsk VI centre last year and learned the benefits of PMEs first hand.

They emphasise that all farms in England and Wales are now within an hour’s drive of an APHA Veterinary Investigation Centre/Partner Post-Mortem Examination provider site, or have access to a free carcass collection service. 

 “Often, on-farm PMEs are done in less than ideal conditions,” Ms Forde told farmers at Thirsk Auction Mart on Monday (17 October). “It’s very hard to look at neurological disease for example and we don’t have the facilities and support the VI centres do.

See also: Benefits of grass-fed label to face scrutiny

“We will always do the best job we can, but it can be dark and rushed and sometimes too late if we have to go to the knackers yard the next day.

Time is of the essence – as animals decompose, the evidence of what killed them and important tissues we might need to study disappear too.”

Ms Lyle said that VI centres play a critical role in uncovering costly iceberg diseases like Johne’s, maedi visna and jaagsiekte as well as very simple causes of death.

“Sometimes stock die because of simple things,” said Ms Lyle. “VI centre post-mortems have discovered farmers dosing lambs incorrectly. This leads to a difficult conversation but without the PME, how many more would have died?”

Simon Doherty, junior vice president, British Veterinary Association said farmers and vets provide a “vital frontline role” in identifying new and emerging disease. 

“A robust surveillance system is vital to the health of UK livestock as well as wider public health,” he told Farmers Weekly. “As a country we need to be alert to the threat posed to our livestock, food chain and agricultural business by disease incursions.” 

Questions to consider before PME

  • How long has it been dead? Specimens are ideally inspected within 24 hours
  • Is It decomposing? Specimens last longer in winter.  Moving a specimen out of sunlight and somewhere cold helps preservation
  • How is my flock longevity? Average ewe replacement rates should be 20% or less
  • Is my ewe mortality below 5-7%
  • Do I have an abortion problem? 2% abortion is normal, above 5% requires action
  • Am I losing too many lambs? Birth-to-sale mortality should be 8% or lower
  • Are my lambs growing normally? Under 250g a day is a sign that something is hindering growth

How much does it cost?

Test

Cost*

Maximum turnaround

Hookworm

£28.50

5 days

Toxoplasma gondii

£39.70

3 days

Maedi visna

£10.80 (single) £8.50 (10+)

5 days

Border disease antibody

£13.50

8 days

Ecto parasites

£23.40

3 days

Rotavirus antigen

£16

7 days

APHA VI Centre locations

  • Starcross, Exeter, Devon
  • Bury St Edmonds, Suffolk
  • Weybridge, Surrey
  • Shrewsbury, Shropshire
  • Carmarthen, Carmarthenshire
  • Thirsk, North Yorkshire
  • Penrith, Cumbria

SAC Disease Surveillance centre locations

  • Thurso
  • Inverness
  • Aberdeen
  • Perth
  • Ayr
  • Edinburgh

* Prices given for APHA centres and can vary according to sample number. Farms are billed through their vets following diagnosis.

Issues flagged up by APHA surveillance

Condition/Disease

Description

Oxyclozanide toxicity

Study of toxicity levels of anthelmintic used to control fascioliasis in cattle, sheep and goats. Frequent symptoms are depression, loss of appetite and diarrhoea.

Vitamin A toxicity in milk powder

Lambs were put down after a milk powder was recalled containing 30 times the recommended vitamin A levels.

Tay Sachs disease in Jacob sheep

A nervous system disorder seen from lambs being very young. Has led to gene therapy studies.

Anthelmintic resistance monitoring

Laboratory testing wormer efficacy saving on wasted time and money on wormers that don’t work.

Schmallenberg resurgence

Testing still-born and malformed lambs each lambing time to monitor for Schmallenberg since first being found in January 2012.

Microphthalmia in Texels

Extremely small or absent eyes and blindness in lambs. A congenital defect from a mutation.