A thorough Johne’s control plan, combined with close vet and farmer collaboration, has been the recipe for success in managing Johne’s Disease on a dairy farm in Leicestershire.
Alistair Hughes, farmer and business partner says, “The key to strong Johne’s management is making sure your team are on board. We employ five people and each individual needs to understand exactly why we do things a certain way and are rigorous in implementing it. An essential part of our Johne’s control plan is thorough staff training.”
Johne’s Disease was introduced to the 600 strong dairy through the purchase of what were believed to be healthy cows during an expansion phase of the herd nearly 15 years ago. The original herd was Holstein Friesian but has since been crossed with NZ Friesian, Scandinavian Red and KiwiCross. Around that time the farm moved to an autumn block calving grazing system.
A rising incidence of Johne’s Disease in the herd was identified between 2005 and 2009 but at that time the Herdwise approved screening scheme for Johne’s, testing the whole herd on a quarterly basis using milk recording samples, didn’t exist. A firebreak vaccination program was put in place and worked well in controlling clinical disease however there were complications with TB testing cross-reacting with antibodies to Johne's and interfering with the TB tests. Leicestershire moved to annual TB testing during this time making continuing vaccination risky.
Vet Pete Orpin, Clinical Director of the Park Vet Group. “A review of the Johne's Control Strategies and risks was undertaken and a different control strategy was selected. We selected Improved Management with strategic testing using the quarterly Herdwise milk testing program”
He continues, “This option uses strategic individual cow testing to identify those cows most at risk of spreading Johne's disease and implementing management changes to break the cycle of transmission for these cows only was considered a practical solution. This allowed us to focus management changes at the cows posing the highest risk whilst allowing normal management of the remainder of the herd.”
A detailed, bespoke control plan was created identifying key areas of improvement:
- Improved slurry management by avoiding the use of cow slurry on youngstock pastures
- Reducing risk of faecal contamination of “green” calf areas where the heifer replacements were sourced.
- Tighter control on culling/ breeding management to remove the most infectious cows promptly
A detailed, Johne’s specific risk assessment using Myhealthyherd is also repeated annually highlighting the main risks of disease entry and spread and helping to predict the future prevalence of the disease in the herd.
Peter Orpin explains, “The herd started to really progress with the rigorous control of Johne’s Disease. The incidence level reduced significantly but then plateaued at 2-4%. More had to be done.”
Together, Pete and Alistair worked on further reducing risks for Johne’s Disease developing a strategy for more rigorous use of disinfectants, including the transport trailer used to collect calves from the calving paddocks and reducing human cross over between areas.
Alistair Hughes says, “We have implemented an “all in all out” policy, where we kept calves together, moving them as a group, allowing complete cleaning of the facility between groups. This was made possible by introducing plastic lined walls which can be efficiently disinfected.”
Full focus was also given to breeding cows, assessed prior to dry off and breeding and allocating cows to categories for culling, do not serve, breed to terminal sire or delayed breeding. Frequent testing allowed the creation of a low risk group (green cows) and a high-risk group (red and amber cows). All high-risk cows are marked with tail tapes and segregated at dry off, preserving the calving areas for low risk cows only.
Alistair says, “All test positive cows who are fit enough to stay in the herd are shifted to breeding within the last 6 weeks of the calving pattern. The first 6 weeks is allocated for a “green calving line” for cows calving outdoors with early removal of calves and a “green calf line”, with all heifer calves reared in clean disinfected group pens. The colostrum is pasteurised and the calves fed artificial milk.”
In 2018, any calves from test positive dams were excluded from the green calf areas and reared to beef or culled. No calves from test positive cows are retained for breeding. Pete Orpin says,
“We now are at the final stage of tightening control of JD and the plan is to source replacements from the lowest risk cows in the herd and to protect them from infection during their lives”
Finally, close focus was put on hygiene and the environment for both calves and cows. Pete explains, “The green calf line has led to very little calf scour with typically less than 0.5% calves treated for scour. This clearly shows how little calf faeces is getting into the mouths of other calves.”
The entire herd is now tested via the Herdwise scheme with very few vaccinates left. All results are carefully managed and interpreted on a cow by cow basis. Using Myhealthyherd and Herdwise, Alistair and Pete are able to manage risks and predict herd health into the future.
Today, predictions are for a declining prevalence of the disease on farm and risks are tightly managed. The number of cows classified as J4 (amber cows likely to be in the subclinical phase of the disease and infectious) has reduced to less than 2% of the herd. Data also shows a decline in test positive animals born on the farm and in the last 3 years nearly all new infections have been eliminated with only green cows remaining.
Alistair says, “There is no magic bullet to this condition. To reach the position we are in now has taken years, working with Pete and accepting that we can’t change everything at once. Working with your vet to create a detailed risk assessment and control plan is the first step. It is then down to the whole team to make sure no stone is left unturned. Don’t do half a job and expect the best returns.”