What's new

New data spurs development of Johne's Management Systems

NMR will be demonstrating an extended range of management services for the assessment and control of Johne's disease in GB dairy herds at this year's Dairy Event and Livestock Show, NEC, September 6/7.

Since the introduction of the Johne's 30-cow screening initiative in January 2011 more than 700 herds have carried out individual milk sample tests for Johne's antibody on groups of 30 cows. Of these almost 70% found at least one positive cow in their 30-cow screen.

"This initiative, by milk buyers, vets and NMR sister company NML has raised the awareness of Johne's in UK dairy herds," says NMR's Ben Bartlett. "Many producers have been surprised to find that there are cases in their herds. This is because Johne's is largely a subclinical disease and it is very common for Johne's to be ‘lurking' in a herd and manifest itself when symptoms become clinical. By this time much damage has already been done. Cows may often be culled for other reasons before they show clinical signs of Johne's."

Cow affected by Johne's Disease - clinical symptoms

Included within NMR's range of Johne's control services is a biosecurity assessment that establishes the risk of entry or spread of Johne's and the development of the disease within the herd.

"Predictions based on individual farm risk assessments show that 95% of herds face the prospect of a significant increase in the prevalence of the disease if action is not taken now to manage the risks of spread," adds Mr Bartlett. "This is great cause for concern. It is also evident that, whilst some herds do not have the disease, they are at high risk of the disease entering the herd due to limited biosecurity controls. It is just as important for these herds to recognise the risk and protect their status as it is for infected herds to bring the disease under control."
It is recommended that all herds should look to establish their Johne's status then plan a control programme based on the results. To provide the tools to meet the needs of all producers NMR is extending its Johne's milk testing services with the introduction of Johne's Essential at the Dairy Event and Livestock Show. Available to milk producers, including those not currently milk recording, this service provides basic quarterly screening.

Many producers and their vets are already reaping the benefits of quarterly milk test screening through NML's Herdwise service; a service that uses NMR milk samples and presents results and analyses through the web-based Herd Companion. Many vets use this screening programme as part of a more comprehensive control plan and are able to develop control measures specific to the farm.

THE DATA
An analysis of data from herds on Herdwise shows that Johne's can quietly eat away at herd health, production and fertility, well before the problem becomes obvious on farm.

"We have analysed two years of Herdwise screening results and compared animals affected by Johne's alongside their contemporaries across subsequent lactations. "The cows affected with Johne's - that showed high levels of antibodies in their milk samples and are classified through Herdwise as ‘red' cows - had significantly lower yields than cows with medium or low infection in their current and in earlier lactations, even before it was obvious that they were affected by Johne's," says Mr Bartlett.

"In a 200-cow herd with 10 high risk Johne's cows - or 5% - the difference in lifetime daily yield compared with a low risk herd has been shown to be 2.4 litres. Projected across two and a half lactations and based on an average milk price of 28p a litre this amounts to a loss of £12,096."

Cell count averages among high risk Johne's cows were 290,000/ml compared with the low risk group where the average was 190,000/ml.

"The trends emerging from Herdwise and the clinical and sub-clinical results seen on farm are sufficient to encourage producers to take Johne's very seriously. "There's no doubt that taking measures to control the disease, which need not be very costly, will pay hands down and, working with vets, we will be promoting the benefits of managing Johne's at the Dairy Event and highlighting the tools available to assess the herd status and manage the risks."

ENDS

For more information contact:
Ben Bartlett, NMR Business Development Manager and NML director, 07974 313269 or
Steve West, NML Healthcheck manager, 07500 773085 or
Karen Wright, 07860 504047 karen@karenwrightpr.com