Necropsy of fallen stock to inform cost-effective interventions to improve health and productivity on UK cattle farms

Project number:                    74109

Lead contractor:                   B. W. Strugnell

Partners:                                   F. M. Lovatt

Start & end date:                   01 January 2014 – 29 April 2015

 

The Problem:

No one likes losing an animal, and beef and sheep producers have previously relied on AHVLA to carry out tests and post-mortems.  However there have been changes to how AHVLA are offering services, which may mean limited access.  The centres that are remaining open in England are Penrith, Thirsk, Bury St Edmunds, Shrewsbury, Winchester (until 2015) and Starcross.  Remember that AHVLA’s main objective was to monitor for new diseases or changes in patterns of an existing one, rather than offering a diagnostic services for farmers, which can still be done with the new structure.

It is likely that the gap left will be filled by vets offering a post-mortem service, and this project is investigating what the future may look like.

 

Aims and Objectives:

  • To establish the feasibility of operating an accessible, sustainable and affordable post-mortem based diagnostic service for cattle and sheep farmers at a Fallen Stock Collection Centre (FSCC)
  • To prove that carcases for which a post-mortem is requested can be accurately identified, in terms of the farm of origin and the private veterinary surgeon responsible
  • To establish that background information can be obtained for each case
  • To investigate potential problems of cross contamination in the wagon, so they do not result in misdiagnosis
  • To report back the results of post-mortem and on-farm interventions to the farmer and his vet promptly and conveniently
  • To provide a cost-benefit for post-mortems

 

Approach:

This project is being done with Ben Strugnell and John Warren ABP (FSCC) in County Durham.  The aim is to perform 1,350 post mortems on cows, cattle, calves, ewes and lambs.  EBLEX is funding 50% of the cost of the post-mortem, and are encouraging producers to fund the other half.

For this project, if an animal dies, the producer will ring John Warren ABP to arrange pick up and will be asked if a post-mortem is wanted.  If the producer says yes, the animal will have a tag placed around its leg by the collector, and a post-mortem will be performed by a vet once it gets to the FSCC.  The vet will ring the producer to collect some background information, and then the report will be sent to the producer and their vet.  It is hoped that an early warning system will be established; for example once the first case of nematodirus or fluke is diagnosed then a wider network of producers will be notified, perhaps by local press, so they can take action.

 

Results

  • 1,383 carcases in 1,225 submissions from 906 beef and sheep holdings were subjected to post mortem examination at a fallen stock collection centre at the request of the farmer or his veterinary surgeon
  • Diagnostic rates were good and in many cases the information gained was used to make real improvements in on-farm productivity

 

For lambs 

• Parasitic gastroenteritis, pasteurellosis and clostridial disease accounted for a significant number of lamb losses. There is much scope for improved management of these preventable diseases
• In many cases, prompt diagnosis of seasonal disease enabled prompt treatment of the group to prevent further losses (e.g. coccidiosis, nematodirosis)
• Several unusual diseases were diagnosed, suggesting that this approach may also provide sensitive national flock disease surveillance

 

For adult sheep 
• Iceberg Diseases (Johnes disease, OPA) were common. There is a need for an evidence base to underpin interventions to manage these diseases once diagnosed in a flock
• Management-induced diseases (dosing gun injuries, endocarditis, lung abscessation) were diagnosed; refinement of management should reduce such losses
• Control of many diseases of adult sheep requires longer-term flock health planning rather than immediate action

 

For calves 
• Respiratory Disease is a major source of economic loss and there was scope for better application of best practice (ventilation, vaccination, cattle flow, control of potential immunosuppressive factors)
• Many causes of death were a direct result of insufficient colostrum intake or suboptimal environmental hygiene at calving
• Some diseases of unknown aetiology diagnosed; more research work required
• Some rare diagnoses made; this may be a sensitive method of livestock disease surveillance

 

For growing cattle
• Respiratory disease in the housed period and clostridial disease outside accounted for a large part of the diagnoses
• Some more unusual diagnoses diagnosed (Clostridium perfringens epsilon intoxication, nonsuppurative encephalitis)

 

For adult cattle 
• Johnes disease was commonly diagnosed in the suckler herd at post mortem examination, suggesting that earlier intervention was lacking
• Some scope for better prevention of fog fever, lungworm, and BVDV mucosal disease

 

IMPLICATIONS FOR FUTURE WORK
• Farm productivity could be improved by access to an affordable carcase-based diagnostic service in other parts of the country
• Some principles from this project could be applied to FSCCs elsewhere to facilitate this
• Initiation of a ‘National Fallen Stock Necropsy Scheme’ to address obstacles to wider adoption of the principle, funded by stakeholders, is suggested. At present, main obstacles comprise availability of personnel and funds