Case Studies

The Banks Family have farmed in Yorkshire for many generations. Their farming operation today includes a 600 head dairy unit alongside a well-established arable business. They have sold their milk to Arla for twenty years and play a key and active role in promoting the dairy industry through events such as Open Farm Sunday.

They have doubled their herd size from 300 to 600 animals in 6 years, using only home bred heifers, with the aim of increasing to 800 animals. The control of infectious diseases is therefore paramount allowing them to achieve good health and fertility to breed replacement animals in the most efficient way. The breeding of home bred replacements is key to supporting their commercial Holstein herd which is closed, except for the purchase of a stock bull. The bull is always carefully sourced from a CHeCS accredited herd and is kept in a separate bull pen and used only to service specific animals which are moved to him, preventing his access to the entire herd.

The farm has always been very proactive with regards to high herd health and welfare. The installation of a new 60-point rotary parlour, to support their herd expansion, has only encouraged them to continue to improve the overall health and welfare status of the herd. The whole farm team work very hard to ensure that processes are in place to minimise the risk of introducing and spreading infectious diseases on farm. This attention to detail has already paid off with the herd successfully eradicating BVD over seven years ago.

The farm has very good biosecurity measures, on farm cleanliness and exceptional colostrum management processes. All colostrum is harvested in a careful manner, with clean udders and teats, and clear labelling, allowing full traceability and ensuring a direct dam-calf pathway. All calves have individual milk buckets and the dedicated calf rearing team make sure that pooling of colostrum never occurs. The annual targeted 30 cow screen for Johne’s disease for the past 10 years has not demonstrated any positive animals in these targeted groups. The introduction of the Arla 360 initiative has however stimulated discussion about increasing the frequency Johne’s disease testing, so they are now carrying out the 30-cow targeted screen quarterly. It is hoped that this will increase the overall test sensitivity and enable them to demonstrate further freedom from disease.

The Wildon Grange team have been highly invested in the long-term overall health of the herd, and have worked alongside & and in conjunction with their proactive veterinary team at Bishopton Veterinary Group, to develop infrastructure and processes that are robust. This allows them to be highly effective at controlling infectious diseases. They have a strong team approach and ensure that all staff are well trained to ensure they understand both the processes and their specific significance. Whilst Johne’s disease has never caused apparent clinical problems, it is part of a rigorous approach to overall herd health and control of infectious diseases.

One farm in the north of England have found strategy 2 of the National Farm Management Plan to be successful in their 450 Holstein Friesian dairy herd. They have used this strategy for approximately 6 years.

What does the Johne’s plan look like on farm?

The farm operates as a closed herd and has done so for more than six years. Meticulous screening was carried out when the farm first expanded the herd seven to eight years ago. This expansion marked the first time that new cows were brought into the herd for twenty years. The farm uses calf hutches to minimise the risk of disease transmission through nose to nose contact. This method of housing also allows closer monitoring and a faster detection and response to any arising health issues. Milk powder or clean milk harvesting for calves is employed to further reduce the risk.

Why was this strategy chosen?

The farm has no evidence of clinical disease and has not had any laboratory positives for over twenty years. They breed their own replacements so as to stay free from disease.

What benefits has the farm found from using this strategy?

The farm is not affected by the costs associated with testing. There has been no evidence of MAP on the farm.

What other tips could you offer in support of the Johne’s strategy?

For success, the strategy – as with any part of the Johne’s Management Plan requires the farms commitment to remaining as a closed herd or to sourcing low risk replacement milking cows of high quality.

Andrew Gilman farms 200 cows plus followers on a privately owned 400 acre estate farm on the outskirts of Tamworth in Staffordshire. His family have farmed there since the 1900's and in the last 12 years Andrew has built cow numbers up from 80 to the current 180 now milking. Initially loose housed, the expansion of cow numbers also resulted in a new cubicle shed with 140 deep sand bedded cubicles, a decision that has seen a marked reduction in mastitis incidences and overall herd cell count. The herd initially increased to 100 and then two years ago up to 140, at this stage an additional 50 cubicles were added to the main cow building allowing for the further expansion to the current number. On three times a day milking the cows are housed all the time and fed a TMR diet of grass and maize silage, a soya and rape blend, bread waste, Trafford Gold and additional fats, yeast and minerals. Dry cows and heifers graze the 70 acres of grassland during summer, with an additional 70 acres available for rotation; 100 acres are allocated to growing maize and the remaining land mass is sown with wheat. The calving pattern is all year round with the herd averaging 10,500kg at 3.8% fat and 3.3% protein. In expanding numbers cattle have been purchased from both Holland and France, guaranteeing TB free stock alongside having a high health status.

Andrew explains their first experience of Johne's was with a Limousin stock bull, 13 years ago which tested positive for Johne's and was culled as a result. Over the last ten years they have adopted quarterly milk testing for Johne's as a key way of monitoring the status of the disease within the herd. In addition they have adopted several control strategies for any cows that have a high test. Dry cows on the farm are split into two groups, a 'far off' group and a group close to calving (3 weeks up to calving group) Any suspect Johne's cows are not allowed in the close to calving group and instead remain with the far off dry cows and then are snatch calved. The cow then enters the main group immediately following calving. The milkers are also split into two groups, the first are fresh calven cows that stay in this group till around 120 days, by which stage they are hopefully pd’d back in calf, when they move into the second group. A Holstein bull is run amongst this group during the day time to sweep up any cows not in calf to try and tighten the calving pattern. The bull then spends the evenings amongst the heifer group to keep age at first calving down as well. When buying a bull, Andrew has in past bought from a closed herd in the locality with a known high health status and recommended by his vet. The bull will then be used on the herd for around 21 months being replaced before his offspring are ready to breed.

The second control against Johne’s that Andrew is confident has reduced the incidence of disease in his herd is ensuring colostrum is only taken and frozen from clean cows, reducing the possibility of transmission to new born calves. Lists of Johne’s cows are situated at varying points around the farm as a constant reminder. Milking three times a day means there is always someone being vigilant around the cows, either one of the two full-time staff; Andy and Nigel or Andrew himself. Breeding any suspect cows to a terminal beef sire is routine procedure and a final control measure. All beef calves are sold on and only dairy replacements are reared.

Keen to get the highest performance out of his cows, Andrew has three-monthly meetings with both Kite farm consultant, David Levick and vet, Rose Jackson or Olly Maxwell of Scarsdale Veterinary practice. He is sure bringing together both the vet and the consultant in the same meeting reaps the best results and clear advice and guidance, leading to successful results. With fortnightly routine vet visits Andrew works closely with the vets at Scarsdale, they have access to his milk records and performance measures and with the shared information they together have formulated an effective herd health plan.

After ten years of regular screening and implication of several protocols again Johne’s, Andrew has not had any red cows for several tests now and the herd has only two orange cows. From past experience cows that have tested positive are often culled for other reasons/ailments and by continuing with the quarterly milk testing and following the procedures in place he is optimistic that the incidence of the disease is under control within his herd.

Looking forward if the current milk industry climate was to upturn Andrew would like to look at further expanding to 500 cows providing the costings stack-up. In the meantime in the short term the next investment will be in replacing the current heat detection system that is ten years old. Having the most advance technology for heat detection will see them use more sexed semen to breed herd replacements and then beef semen across the rest of the herd.

Stephen Bone farms 970 acres across three farms. Trengwainton Farm in Madron, Cornwall is home to the 220 cow milking herd averaging 10,000kg at 3.9% fat and 3.3% protein with a calving interval of 384 days. The milk is sold to Davidstow on a cheese contract, their focus is on breeding to improve herd health and milk proteins. Ongoing monitoring of milk protein levels can also be used as a good indicator of the cows’ energy status. Calving is generally between August and January which provides plenty of opportunity to get the cows back in calf whilst they are housed over the winter months. They are fed a winter total mixed ration consisting of grass and maize silage, barley whole crop and Maximom urea treated barley grain. The cows are topped up with concentrates in the parlour fed according to yield and age.

Stephen first began testing for Johne’s disease in his dairy herd five years ago. At the time he noticed that they were losing two or three cows a year that were repeatedly treated for varying ailments with no success. When tested for Johne’s disease on blood they often came back positive and some cases were seen to be showing clinical signs of wasting. This lead to the decision to take proactive action and they began milk testing quarterly.

On the first test the herd of 200 cows were sampled. The results showed three red (positive) cows, two orange and the rest green (negative). Despite the relatively low prevalence of Johne’s disease, Stephen was keen to take further proactive action to help improve and maintain their Johne’s disease status.

Having a long association with Rosevean Vets, Stephen consulted with vets Duncan Bruce and Matthew Berriman on the next course of action. ‘Duncan and Matt have always been very supportive and proactive. We felt it was vital to get a protocol in place on the farm as quick as possible’ explains Stephen. As a starting point any offspring from cows that had tested positive were given a red ear tag and if they weren’t already in calf, they were served to a beef breed. This meant that only ‘clean’ cows were served to dairy sires to produce replacements. If a cows results changed and they became red during its lactation it was given a red ear tag, snatch calved and the calf was also red tagged at birth to ensure neither the dam nor calf was kept in the milking herd.

Tagging all the offspring seemed a daunting task to begin with. In their first year of implementing the ear tagging, of the 65 heifers they had to serve 20 had red tags in their ears and so were served to beef breeds. The second year saw similar numbers, however Stephen persisted with identifying possible ‘dirty’ animals with the long term aim of controlling the disease in the herd at the forefront. In this last year however, there were 104 heifers to serve and only one had a red tag. Although it has been a long process the results of the stringent testing and tagging protocol is now demonstrating how successful it has been.

Although they have continued to milk red tagged cows through to the end of their lactation, they have immediately culled any that showed any suspect clinical signs, including those showing signs of scouring. ‘Red tag cows are definitely more prone to mastitis and lameness’ adds Stephen and in addition have poor fertility, which has been particularly obvious during routine scanning sessions. The milking herd now stands at 220 head of cattle with only 5% having red tags. Overall, the herd is much healthier and this year for the first time, due to reduced culling and improved fertility, they have had a surplus of replacements and therefore have been able to sell 15 heifers, with full confidence that these animals are of high herd health status. Alongside implementing tagging and testing the farm has also tightened up on bio security. Two of the four calving pens are allocated purely to calving red tagged cows. These two ‘dirty’ pens are away from the two ‘clean’ ones and boot disinfectant points are located at the gates of each pen.

All calves are fed on powdered milk from birth to break the cycle of transmission of Johne’s disease through the colostrum or milk. Beef calves reared separately, again minimising the risk of Johne’s disease transmission to dairy replacement animals, before being stores sold off farm as store cattle. Disinfection points are located at the entrance/exit of the calf rearing sheds. Stephen adds that awareness is key and it’s amazing how quickly the mind set of increasing bio security sets in. ‘On a recent on farm meeting we were conscious to keep visitors out of the central feed passage after they had been amongst the cows, something simple but key to ensure the cows didn’t ingest any ‘dirty’ feed’.

Ensuring his staff follow the protocols that have been put in place has also been instrumental in the success of the control programme. Stephen’s herdsman Nigel Mountstephens has been employed on the farm for over ten years and alongside full time staff William Bucket and William Jelbert their attention to detail and appreciation of the protocols on farm has been fundamental to the success of the farms control of Johne’s disease. Nigel regularly milks and his vigilance towards the cows has been a critical part of the control explains Stephen. It is important that the staff both have and share the knowledge of the disease and more over act up on it. ‘We have always followed the rule that once a red always a red’ Stephen says and now they have just 11 suspect cows in the milking herd at least half of which are due to be culled this year.

He concludes that he will definitely continue with regular testing. In the five years of testing the cost of milk sampling is far cheaper than the cost of having a Johne’s disease positive cow shot and disposed of on farm. Through being part of the Johne’s disease initiative and working with Rosevean Vets, the farm has actively implemented the strategic control methods in the National Johne’s Management Plan, from improving farm management and implementing protocols to the regular testing and culling of infected animals. Using beef sires as a terminal sire on any cows red tagged has also played its part in reducing the number of Johne’s disease suspect cows in the herd. A Hereford bull is used as a sweeper bull on the farm, but Stephen makes sure that the bull is purchased from a herd with a known high health status. Finally, Stephen views the control of Johne’s disease in dairy herds as essential. ‘Acting against diseases like this is a form of protecting ourselves as farmers against unproductive cows in our herds which ultimately just cost you money’. His results from the last five years of testing, together with the hard work and vigilance of his staff, are now showing the benefits of the control programme implemented from the guidance of the Johne’s disease initiative.

For Mike and Donna Bowe at Dalston in Cumbria Johnes disease has been a problem they have been aware of within their herd since 2004 following restocking post Foot and Mouth in 2001. Despite being very proactive in their approach to controlling and dealing with the issue of Johnes, in conjunction with their vets, David Black and Diether Prins from the nearby Paragon Veterinary Group they feel they are still very much learning about Johnes and will in their own circumstances as a true commercial herd which is still expanding, expect it will be virtually impossible to eradicate it within their lifetime - such is the challenging nature of the disease.

They feel passionately that the problem of Johnes is one to be tackled and managed by the whole agricultural industry from farmers, to vets, to auctioneers and many others involved in farming. And that everyone has a responsibility to understand the disease and to play a role in controlling its spread within the farm and between farms. At the height of the problem at Chalk Lodge Farm there was a new clinical case most months, but through annual blood tests and meticulous recording of the risk status of all animals on the farm, initially by Donna and now by Mike and Donna's daughter Vienna, clinical cases within the 700 cow commercial Black and White herd are now rare.

Over time as the joint understanding of Johnes disease between David and the Bowe family has developed, the risk based strategy on farm has evolved. The team on farm has learnt to identify cows before going down with the clinical disease ensuring they are culled with some value. Importantly annual bleeds have been done for the last five years, whereas now cows are blood tested at drying off - creating a more real time picture of the disease as well as the sample being taken at a potentially more stressful time in the animals cycle, as the disease is deemed to manifest itself more when an animal's immunity is challenged or compromised. Mike has considered that in the current climate financial savings could be made by stopping testing - however he acknowledges this would quickly undo six years of good work. Furthermore there is an argument that more can be done to cull cows at high risk in the current farming climate when stock are not as valuable. He also mentions that a strong character is needed in dealing with the disease - making the decision to sell a cull cow for £800 to remove the infected animal from the national herd versus selling on the problem to another producer for £1500 - £2000 requires immense honesty. However there is an underlying effect from the disease on herd performance on many levels - by now actively tackling the issue at Chalk Lodge the herd has seen much better fertility, as well as less lameness, improved cell counts and better calf health, as the herd incidence of Johnes has dropped to its current level of 6%.

Attention to detail and education are two key areas which the Bowe family feel will help the industry tackle Johnes going forward. In the first instance can students, farm staff and farmers be more aware of the disease? Mike feels it can be hard to motivate staff to implement protocols which are so crucial to controlling the disease but can be time consuming and not the 'easy option'- such as making sure milk is not pooled and cross contamination is minimised. For a herd this size until herd expansion has stopped, cows classifed as high risk may not be culled immediately - so alternative strategies such as pasteurising colostrum, followed by feeding all heifer calves with powdered milk, individually penned with dedicated feed and water buckets are crucial. Following a trip to the USA by Mike the family has also spent around £5000 on creating a new calving yard. This has four pens all with locking head yokes and bunkers in front, where the calf, having been snatched, is placed - in front of the dam for bonding and licking, but away from faeces removing most of the threat of dung to calf contamination. The cows calve onto rubber matting, with the whole area washed down and cleaned after each new born. Mike says this new area and approach has been tremendously successful as well as aiding cows cleansing. Any calves from a Johnes dam are marked as such in the calf house, and again Donna and Vienna's record keeping is exemplary in terms of showing the potential passage of the disease through generations - even with some blips when it skips a generation.

Each farm has different abilities and scope to work and control Johnes disease. The Bowe are conscious that space limitations prevent the gold standard approach, which would see red cows calved in an entirely separate area with the calves also reared separately. Either that or the red, high risk animals would be culled immediately, but for now the use of beef sires on these identified animals is another strategy in controlling Johnes. Vaccination is not a route they have gone down, but they note a word of caution in that animals which have been vaccinated will show as positive in the test, something they encountered with bought animals which had been vaccinated. All in all the nature of Johnes determines a farm specific approach for farmers in conjunction with their vets and an open mind to continue learning and modifying how best to deal with the challenges it creates.

Stuart Webster and his herdsman John Hind farm 170 pedigree Holsteins and followers at Aurora Park Farm, Scales located just a mile from the coastline of the Furness Peninsula in Cumbria. The 250 acres is mainly grass, with just five acres put down to whole crop each year, needless to say cows are grazed through summer and then cubicle housed through winter on a diet of grass silage, whole crop and moist feeds.

First cut silage is taken on the 11th May (weather permitting), with second cut five weeks later and a third and final cut taken end of July/early August. Silage is analysed each year and the concentrates fed in the parlour adjusted accordingly. The cows currently receive a 16% protein cake fed to yield to a maximum of 8kg. On this relatively conventional system the cows are performing well averaging 9600kg at 3.8% fat and 3.12% protein, with SCC of 93 x1000cells/ml based on their 12 month rolling average.

Operating a completely closed herd, Stuart and John are focussed on maintaining a high herd health status and as part of this have been monitoring the milking herd for Johne’s disease for five years.

Stuart explains that when they started recording with the CIS, they began milk testing each cow for Johne’s disease as well, adopting Strategy 3 from the NJMP of ‘Improved Farm management and Strategic Testing’. Thankfully test results have always shown a low incidence of the disease and interestingly the only cows that classified red/amber were almost always ones that were on the list to cull anyway.

Since starting the monitoring process, the milking herd are tested every quarter and reviewed with vet Andrew Crutchley at the routine visit. A blood or faecal sample is also collected from any suspicious cows. Any cows showing red from a milk test result and a positive result from a blood sample are considered high risk. If in-calf, they are calved separately and kept well away from the calving pen and young stock until they are culled. John adds they don’t keep any calves from suspect positive cows and are also very careful to ensure no colostrum is taken from them.

Both the regular monitoring and careful management of high risk animals has seen a continual decline in the number of cows falling into red or amber categories on the milk test results and on the latest test the entire milking herd was green. This won’t stop Stuart and John continuing to monitor though as Stuart explains, the testing provides ongoing reassurance and as a closed herd breeding all their own replacements it is important to guarantee the next generation of heifers have no underlying health issues.

Implementing a control programme has being particularly important at Aurora Park as calves are fed, in the first instance, their dam’s colostrum and then reared to weaning on whole milk from the herd. It is therefore essential that the calves are only receiving milk from cows shown not to be shedding Johne’s disease minimising the risk of any possible transmission into the young stock.

The Johne’s disease monitoring scheme is just one part of the infectious disease control plan for Aurora Park Farm, with the herd currently BVD free, Leptospriosis vaccinated and IBR monitored. As the herd is pedigree, maintaining this known health status certainly adds value to any surplus heifers that Stuart sells, he adds that looking to the future they may go a step further and aim to achieve fully accredited Johne’s disease free status.

The fertility figures for the herd also demonstrates how well managed and healthy the cows are. The current calving interval is running at 384 days, average days to first service 55 and average days to conception is just 87. On average 2.2 straws are used per cow, with AI commencing from 40 days and 43% of all services resulting in conception. Any cows not served by 42 days are presented at the next routine vet visit for treatment. If treatment is unsuccessful they are programmed for fixed time AI (Ovsynch). Aiding them in keeping the calving interval down is the Silent Herdsman System and they use a mating programme from Semex to minimise any inbreeding. Sexed semen is used on heifers, with a Hereford bull used to sweep up and an aim to calve them in at two years old. The majority of the rest of the herd are bred pure with a small amount of British Blue and Fertility Plus semen used to sweep up and for the lower end of the herd.

Operating a replacement rate of around 25%, the current herd dynamic is a varied mix of ages from the 41 heifers milking ranging through to some 10th calved cows. With improved herd health over the years and the use of sexed semen in the heifers providing more available replacements, Stuart and John have seen a noticeable and welcome shift towards more voluntary culls, with three key areas looked at, lameness, fertility and cell counts. Being in the position to make voluntary culls has also attributed to improvements in the herds performance.

Looking to the future there are plans to make some modifications to the farm, in particular improving the cubicle housing and moving from paper waste and straw to rubber mats to reduce hock swellings and improve cow comfort. The parlour is also targeted for a remodel scaling up from the 12x24 herringbone to a 20x24 reducing milking time, although there are no plans to increase herd size as land is the limiting factor. Herd health will remain a priority for Stuart and John and alongside their careful management and guidance from Andrew at Westmorland Veterinary Group the Aurora herd will continue to perform.

Case Study Strategy 3: Improved Farm Management and Strategic Testing
Ben Brearley, The Livestock Partnership
Kate Lywood, Marshalls Farm
 
Kate Lywood manages the family farming business at Marshalls Farm, Kirdford and has been working with vet Ben Brearley to control Johne’s through Improved Farm Management and Strategic Testing.  

Marshalls Farm is a 650 acre dairy and arable farm in West Sussex, with plans to milk 450 spring calvers with young stock. It has been a closed herd for over 30 years with a strong belief that prevention is better than cure, remaining free of production diseases such as BVD and Leptospirosis.  

Their Johne’s plan on farm includes the identification and culling of all high-risk animals and any closely related offspring. They then put management measures into play to help prevent the exposure of young calves to animals which are potentially shedding Johne’s disease but cannot or have not yet been identified by the current testing regime.  

The Marshall family have carried out this approach since the identification of Johne’s disease three years ago. The full benefits of the programme have not been shown yet as it is too early to tell if animals have been infected since the control measures were adopted.  

Vet Ben Brearley said; “We would recommend the early adoption of any Johne’s disease control measures as it is such a long term project. It is important to find out as soon as possible what your risks are, what your likely prevalence may be and to start a control plan early.”

Following one of the six strategies from the National Johne’s Management Plan is helping to deliver control of this challenging disease to farmers across the country.  

Strategy 4: Improved farm management, test and cull

The Milne family; Sandy with Emma, and parents Ian and Dawn alongside their dedicated staff have been dealing with Johne’s disease on their Scottish dairy farm since the mid to late 1990's. Although the definitive source of the disease isn't known, Ian believes it is likely to have come from a few black and white cattle which were bought in to enhance the traditionally red and white herd. Today, they have 400 milking cows on the 1250 acre landmass situated at Brechin, between Dundee and Aberdeen.

In the late 1990's, when Johne’s disease is thought to have started to become a problem on the farm, there is thought to have been an element of ignorance. Cows were being culled due to poor condition and scour, without any knowledge of the underlying cause. At the time, it was common practice at the East Pitforthie and for many others, to pool colostrum for the calves and vaccination was the mainstay control measure for tackling Johne’s disease.

In the early 2000's the farm began testing cattle for Johne’s disease. It became apparent at this stage that the vaccination programme was leading to a number of false positive results, and by February 2008 the vaccination programme was stopped.

In 2003 a new unit was built on the current site at East Pitforthie, which saw the two 120 cow herds run by the Milne's combined onto the one site. The ongoing intention was to push cow numbers up to the 400 mark. By then the family was very aware of the Johne’s disease problem on the farm and planned to cull hard on test results, whilst aiming to expand at the same time.

Strategy four from the six strategies identified by the National Johne’s Control Group has been implemented within the Carcary herd to help control and prevent Johne’s disease. Without a doubt, improvements in farm management and recording have made the biggest inroad. The Milne family in conjunction with their vet, Graeme Richardson of Thrums Vet Group, Kirriemuir, are under the belief that they may be able to eradicate the disease completely in the medium to long term, but this is only made possible by the layout of buildings on farm which facilitate segregation of different groups.

Johne’s disease management protocols on farm now are very regimented, and although it initially took time to get the entire team on board, they now understand the importance and relevance in managing and controlling Johne’s disease. A three coloured tag system is practised on farm. A white tag indicates an animal classed as clear, a blue tag shows the grand-dam tested positive for Johne’s disease and finally a yellow tag shows the animal was snatch calved. Furthermore, all cows and heifers are blood tested at drying off. The unit allows a split in the calving accommodation, with one side designated 'clean' while the other is classed 'dirty'. The young stock and dry cow shed is also solely kept for 'clean' animals.

The farm has also introduced many more set procedures around the time of calving that all aim to minimise and break the cycle of Johne’s disease transmission. These include;

• Segregation: any calf born to a dam that has had a positive blood test for Johne’s disease is either snatch calved or if a heifer calf is not snatched it is identified straight away as being only for beef rather than as a replacement.
• Any calf born from a blue tagged dam is not fed its mother's colostrum or milk. In the office a list of ‘clean’ animals is displayed- extra colostrum is collected from these animals and is pasteurised, bagged and frozen.
• Any milk from Johne’s disease positive dams is only fed to bull calves that are not kept as breeding animals.
• Cows with positive blood tests are culled once they are dried off or if they deteriorate and show clinical signs of the disease, indicating they are likely to be shedding, they are culled a soon as possible.
• All calves, even those born to a ‘clean’ dam, are moved to individual calf housing as soon as possible after birth.

They have also improved their ongoing testing/monitoring and are now doing regular milk testing. From these results, the Johne’s disease status of every cows is recorded annually on the farms computer to improve the detail with which the herds Johne’s disease status is monitored.

Their farm vet, Graeme Richardson, from Thrums Veterinary Practice, said: “Vaccination was introduced as a control strategy when the level was relatively low, whilst vaccination was being practised the level of infection rose, peaking at about 35%. Since stringent management practices were enforced by the farmer alongside a carefully crafted test and cull policy the level has dropped to around 2% and is still dropping.

“The key to successful Johne's control is to establish what actions need to be prioritised on each individual farm. Each one has different circumstances and resources and trying to shoe horn all farms into a tick box exercise does not work. Without doubt, where we have had greatest success is where the farmer buys into the programme of change and we as vets can guide him/her with a bespoke programme of control and risk management.”

Summing up the effect of Johne’s disease and its subsequent control the Milne family say it has led to improved attention to detail on farm which has in addition helped the whole business grow.

Ian tells a poignant story that he felt brought the message home some years ago - a tested clean, prize winning cow within the pedigree Carcary herd calved a strong heifer calf in a clean bedded and isolated area. However, the calf managed to move off the clean area and into an area potentially contaminated with infected muck. Without hesitation Ian instructed the calf to be classed as dirty/infected and to be tagged accordingly as not to be bred from in the future. If you are serious about tackling Johne’s disease there is no room for sentimentality - the disease is ruthless in nature and so must everyone else be in dealing with it.  

Case Study Strategy 4: Improved Farm Management Test and Cull
David Hiscox, West Hayes Farm
Rachel Hayton, Synergy Farm Health
 

West Hayes Farm in Sherbourne, Dorset is a 300 dairy herd in an extensive grazing system, utilising Friesian and crossbred genetics.

Vet Rachel Hayton from Synergy Farm Health introduced their Johne’s management strategy in 2011. The strategy has been overseen by Dave ever since, organising the testing regime, culling decisions and calving and youngstock management as well as making sure the farm staff carry out the necessary practices (including snatch calving) when he isn't there.

In 2011 Johne’s disease was considered one of the major threats to the farm due to the levels of clinical disease seen.

The dairy herd is split into two cohorts (a) the dairy herd producing replacements and (b) the dairy herd producing beef animals. The two cohorts calf at distinct times of year with the former calving between February and May.

The whole herd is milk sampled for Johne’s serology on individual milk samples prior to dry off. Any animals in the “Dairy producing dairy” block identified as amber or red on the milk test are excluded from the calving box and calved in an isolation unit. All calves from this unit are snatched prior to colostral transfer and if this cannot be achieved, they are tagged as “Johne’s suspect” animals and not retained as replacements.

The “Johne’s free calving box” is not used for mastitis, lame of sick cows during this period, as these animals are possibly candidates for Johne’s shedding. Any replacement heifers born to a suspect mother are snatched and fed either colostrum from low risk cows identified on milk testing, or artificial colostrum.  Milk for sick cows under milk withdrawal is NOT fed to replacement calves. There is separate equipment for dairy and beef calves. Dairy replacements are then converted to milk replacer.

This strategy was chosen because the farm had a very high Johne’s prevalence, reflected in a high proportion of test positive cows and a steady trickle of clinical cases. It was felt that improved farm management alone would not lead to a sufficiently rapid reduction in disease prevalence and there was a need to remove animals before they became heavy shedders. However culling all test positive cows in the early days would have led to an unacceptably high culling rate. Therefore a compromise was reached whereby test positive cows are culled as soon as they develop any other problem, or simply look "plain". As a result cows have not demonstrated overt clinical disease for some time. At the same time the intensive management required to calve in replacement heifers is only required during a 3 month period.

Disease prevalence based on serology results has been dropping steadily in the last few years (4/30 positive in the last 30 cow screen) with the result that very low prevalence/eradication is now seen as an achievable option.

For eradication to be a realistic goal the control plan would have to be tightened up further, in ways that could not even have been considered 5 years ago.

Next steps might be:

1. Closed herd. Currently bought in animals calve in to the beef bred cohort
2. Sexed semen to further reduce the number of highly supervised calvings
3. Not retaining offspring born to high risk cows

 

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.”

The Challenge
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.”

The Solution
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 Results
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.”

The Sowray family from Bowes Green Farm have seen benefits from implementing strategy 5 of the National Farm Management Plan in their flying 450 Holstein Freisan herd.

What has been done so far to control Johne’s?
Cows are served to a terminal beef sire and the offspring are sold as premium calves. The aspiration is to source replacements from herds with lower levels of Johne's disease; although status is not always fully understood. Testing of suspect cases is performed and this informs future sourcing strategies from source farms.
As their farm vet Jonathan Statham from Bishopton veterinary warns, cows will still develop Johne's disease and so still need to be removed from the herd.  This number has reduced over time as cows are purchased from generally lower risk herds.  

Why was this strategy chosen?
The herd already sold calves at premium prices, so it was a rational tactic to use a comprehensive terminal sire beef strategy.  

What benefits has the farm found from using this strategy?

• Simplification of calving cow and calf management;
• Small targeted need for MAP testing with associated cost;
• Vastly reduced rearing costs in herd;
• Flexibility to respond to market forces rapidly in tough economic climate

 

What other tips could you offer in support of the Johne’s strategy?
For success, the strategy – as with any part of the Johne’s Management Plan requires commitment to sourcing replacement milking cows of high quality using good networks of trading, alongside a good eye for dairy cattle, good trading skills and a comprehensive vaccination and purchased stock risk strategy for other diseases such as BVD, IBR and bTB in conjunction with the herd vet.

Vet Rob Smith from Farm First Vets in Abergavenny and the Price family at Gelliargwellt Farm have worked hard to develop a keen biosecurity control, aligning to the National Johne’s Management Plan Strategy One: Biosecurity, Protect and Monitor.  Whilst the farm follows Strategy 1, they keep an eye on their Johne’s disease status through quarterly testing.

Price & Co are a family partnership, including a Holstein Friesan dairy farm, as well as quarry and recycling centre. Because of the quarry, the farm is located on a hill in close proximity to industrial units.

The farm has run a successful Johne’s control plan over the last few years and have had no confirmed cases of Johne’s in recent years. It keeps an annually updated and actioned Herd Health Plan, specifically addressing Johne’s which includes advice as follows:

Action Plan

- Milk test cows quarterly using NMR Herd Tracker program. Milk tests need to be taken at least 60 days after a TB test.
- Identify ‘positive’ cows and confirm if infected with Johne’s, using a faecal PCR test. The decision to carry out this further testing is to be done on an individual cow basis depending on milk test result and health/productivity of cow. The decision will be taken in conjunction with the farm’s vet.
- Any animal that has clinical signs that are suspicious of Johne’s will be tested with blood and or faeces as appropriate.
- Efforts are made to harvest colostrum in an hygienic way as possible. Calving pens and calving cows are kept in as clean condition as is possible.
- Slurry from adults is not spread onto grazing ground for youngstock (especially ground used for grazing replacements) where possible. Arable ground is fine. Care is taken with stagnant ponds.
- Biosecurity measures around the calf housing e.g. disinfectant footbaths are instigated to prevent contamination of calf area with adult faeces

If a confirmed case of Johnes is identified this action plan will be reviewed and updated with further control measures, as necessary.

Farmer compliance is key to this strategy’s success.

Case Study Strategy 1: Biosecurity Protect and Monitor
John Peck, Redlands Farm
Chris Gasson, Hook Norton Veterinary Group  

Redlands Farm in Hook Norton is a 450 cow unit, where all increases in animal numbers were from home bred heifers in order to maintain biosecurity specifically with Johne’s disease control in mind. The herd is closed and has been for the past 15+ years, with the only incoming stock being bulls from level 1 accredited herds. The farm tests annually with a whole herd blood test to achieve accreditation.

Using a Biosecurity strategy based on a closed herd, a plan was formulated on the tentative assumption that Johne’s was not present on farm. From historical monitoring, any suspicious clinical signs were tested. These tests came back negative. However, after an increased emphasis from milk buyers, the farm has become more active with monitoring. They have carried our several ’30 cow screens’ on milk samples and then progress to the accreditation route with the SAC. They have now carried out the first whole herd blood test in January which gave 3 out of 464 cow results to be retested.

The initial strategy was chosen as it was a low cost in terms of monitoring, and very little extra work for staff.

“The benefit is the pride we have in not having the disease on farm” says Chris.

Chris also adds: “This approach needs to be dedicated with extra care taken when purchasing bulls; an alternative option could be to purchase embryos instead.”

When planning to increase numbers of cattle it takes 3 years from deciding to breed more heifers to them entering the milking herd. So one of the first decisions to be made when expanding a unit, is to start the ball rolling with inseminating more cows to replacement semen.

There is also a degree of patience needed to do this. Chris believes sometimes that the decision to buy an extra 20 cows to put milk in the tank could cost much more than the value of the milk they bring if the biosecurity and purchasing decisions are not right.

Other notes:

• Plan for ‘disasters’ that would remove cows from the milking herd. Events such as an outbreak of TB, or other disease might lead to a shortfall in the number of cattle.
• Breed extra replacements – this gives options of what to do, the herd can be expanded, more selective culling of lame/low yielding/high cell count cows. Any surplus cattle after that could be sold.
• Chris also believes that in a ‘biosecurity, protect, monitor’ situation any positive serological results need further investigation and should be regarded as screening test, not a diagnostic one.

The Banks Family have farmed in Yorkshire for many generations. Their farming operation today includes a 600 head dairy unit alongside a well-established arable business. They have sold their milk to Arla for twenty years and play a key and active role in promoting the dairy industry through events such as Open Farm Sunday.

They have doubled their herd size from 300 to 600 animals in 6 years, using only home bred heifers, with the aim of increasing to 800 animals. The control of infectious diseases is therefore paramount allowing them to achieve good health and fertility to breed replacement animals in the most efficient way. The breeding of home bred replacements is key to supporting their commercial Holstein herd which is closed, except for the purchase of a stock bull. The bull is always carefully sourced from a CHeCS accredited herd and is kept in a separate bull pen and used only to service specific animals which are moved to him, preventing his access to the entire herd.

The farm has always been very proactive with regards to high herd health and welfare. The installation of a new 60-point rotary parlour, to support their herd expansion, has only encouraged them to continue to improve the overall health and welfare status of the herd. The whole farm team work very hard to ensure that processes are in place to minimise the risk of introducing and spreading infectious diseases on farm. This attention to detail has already paid off with the herd successfully eradicating BVD over seven years ago.

The farm has very good biosecurity measures, on farm cleanliness and exceptional colostrum management processes. All colostrum is harvested in a careful manner, with clean udders and teats, and clear labelling, allowing full traceability and ensuring a direct dam-calf pathway. All calves have individual milk buckets and the dedicated calf rearing team make sure that pooling of colostrum never occurs. The annual targeted 30 cow screen for Johne’s disease for the past 10 years has not demonstrated any positive animals in these targeted groups. The introduction of the Arla 360 initiative has however stimulated discussion about increasing the frequency Johne’s disease testing, so they are now carrying out the 30-cow targeted screen quarterly. It is hoped that this will increase the overall test sensitivity and enable them to demonstrate further freedom from disease.

The Wildon Grange team have been highly invested in the long-term overall health of the herd, and have worked alongside and in conjunction with their proactive veterinary team at Bishopton Veterinary Group, to develop infrastructure and processes that are robust. This allows them to be highly effective at controlling infectious diseases. They have a strong team approach and ensure that all staff are well trained to ensure they understand both the processes and their specific significance. Whilst Johne’s disease has never caused apparent clinical problems, it is part of a rigorous approach to overall herd health and control of infectious diseases.