Larger Herd Sizes Linked to Higher Bovine TB Risk

Farming practices such as larger herd size, maize growth, fewer hedgerows and the use of silage have been linked to higher risk of bovine TB, new research from the University of Exeter has concluded.

The study, funded by BBSRC, analysed data from 503 farms which have suffered a TB breakdown alongside 808 control farms in areas of high TB risk.

The team found that farms with herds of 150 cattle or more were 50 per cent more likely to suffer a bovine TB outbreak than those with herds of 50 or fewer.

Crop production, feeding and landscape features were also important, with the risks increasing with practices linked with higher productivity systems.

For every 10 hectares of maize - a favourite food of the badgers that play a role in transmitting the disease - bTB risk increased by 20 per cent. The feeding of silage was linked with a doubling of the risk in both dairy and beef systems.

Each extra kilometre of hedgerow was linked with a 37 per cent reduction in risk. This is likely to be because there is less contamination of pasture by badger faeces and urine in hedgerow-rich areas - read more.

This week, we also featured three reports from the AHDB Beef & Lamb conference in Warwickshire, where delegates found out that the UK is trying to put in place a ‘comprehensive agreement’ for exports to the US.

The UK’s request for access is taking some time to process, due to the inclusion of both beef and lamb, unlike Ireland, which requested beef access only as soon as BSE restrictions were lifted.

“The UK is going through the process, but it is a long process to work things out,” said Stan Phillips, Agricultural Counsellor at the US Embassy in London - read more. 

Delegates also heard from Professor Michael Lee on sustainable livestock production in grazing systems, and Dave Harrison on the importance of the Asian market to New Zealand's beef exporters.