Some of you may know I chair Cattle Health Certification Standards (CHECS), which has set standards for cattle disease control in the UK and Ireland for more than 20 years.
In April, the CHECS board made a tough decision.
For three years, there have been differences of opinion between CHECS health schemes about testing for Johne’s disease.
Johne’s is difficult. You cannot eradicate it and it causes progressive wasting and huge losses.
It has also been linked to Crohn’s disease in humans, so must be dealt with robustly.
I am not going to get technical. The important bit is the blood test which is designed to detect antibodies for the MAP bacteria which cause Johne’s disease. This can have up to 2 per cent false positive results.
Some health schemes cross check positive results with confirmatory dung tests, some do not and some do sometimes.
A dung test does not clear the animal for breeding but does for calculating overall herd risk level.
However, the dung test looks for actual shedding of disease, a stage on from infection. The dung test also has a high incidence of false negative results, meaning there is a far greater chance of ‘clearing’ an infected animal than the blood test has of falsely accusing it.
If this seems petty, think about this. Two herds with the same rate of infection could be given different risk levels just because one had a false negative dung test.
There are trading, financial, health and reputational consequences.
Last month the CHECS board stepped in to rule that follow-up testing will only be allowed in low risk herds – those with 2 per cent (or one animal) positive blood tests or fewer.
There has been quite an outcry. Breeders are understandably concerned their herds will jump risk levels and what that will this mean for their sales and their reputation.
However, as one health scheme pointed out, inconsistent application of the rule has been a problem and this change affects everyone.
CHECS is an important tool for breeders, but everyone needs to trust it.
With Johne’s disease now reportable in the EU, the UK must improve its reputation for control.
We must also think about the losses and waste we suffer from cattle disease generally, the extra greenhouse gas emissions, the reduced productivity and profitability and the risk of zoonosis.
This change may be painful in the short term, but the bigger picture is critical.