Regenerative Agriculture Practices Provide Benefits for Ruminant Health

Have you noticed cattle and sheep grazing in fields with grass up to their knees recently? Does the term ‘herbal ley’ mean anything to you? Regenerative agriculture is becoming more mainstream, so what can farm vets do to help clients who want to protect biodiversity and soil health?

Last year the BVA released a statement on sustainable animal agriculture pointing out that the “veterinary profession is well-placed to advise and influence sustainable animal husbandry practices at whole system levels” with recommendations that “policies relating to sustainable animal agriculture must also address the use of natural resources and the protection and conservation of wild species, habitats, and biodiversity”[1].

Many systems of farming can lend themselves to reducing emissions and the protection of natural resources, however this article is focussed on regenerative agriculture, and introduces the uninitiated to this topic from a veterinary perspective. Here is a summary of recent scientific findings on the subject, with some input from farmers and researchers who are already embracing the regenerative approach.

What is regenerative agriculture?

Regenerative agriculture is a set of principles that aim to enhance ecosystem resilience and mitigate climate change. This includes methods to improve soil health and support greater biodiversity [2]. Regenerative agriculture shares similar principles with organic farming; however not all organic farms may be considered regenerative and vice versa. Success in regenerative agriculture focuses on outcomes such as an increase in soil organic matter and insect counts; and each farm is likely to have a different approach suited to their soil type, local climate, and production goals.

How can vets get involved?

Often these markers of regeneration are monitored by eye and as such there are opportunities for vets to provide recording and analysis bespoke to your client’s farm in line with their goals and values. The transition into regenerative agriculture can be a challenging time with lots of change and perceived risk, and veterinary input can be useful to assist with monitoring livestock welfare and production over this period. The vet and farm team can record outcome measures, make appropriate adjustments, and monitor until a beneficial and workable system has been established. Regeneration is complex and continual, involving all parts of an ecosystem from the nutrient and water cycles to soil organisms, plant species, wildlife and livestock. Any type of farm can incorporate regenerative practices, but this article will focus on cattle and sheep.

Managing parasite burdens in a regenerative way

Vets can become involved in regenerative agriculture on farm through reassessment of parasite management. Anthelmintic use reduction is key to reduce the impact of resistance on animal production and welfare. Anthelmintic use (particularly avermectins) can also lead to decreases in invertebrates such as dung beetles [4,5,6]. These beetles incorporate faeces into the soil which builds organic matter, therefore improving soil health and reducing the need for fertiliser. They also disrupt nematode lifecycles and carry phoretic mites which eat fly larvae. Alternatives to chemotherapeutic anthelmintics are an area of interest for scientists and there is a wide body of literature assessing possible solutions.

Many plants suitable for grazing produce secondary metabolites such as condensed tannins and sesquiterpene lactone which have been shown to be effective at reducing internal parasite burdens [7,8]. Studies in vivo have found that feeding bird’s foot trefoil, sainfoin, and chicory reduce gastrointestinal worm burdens in cattle and sheep. Lambs infected with multiresistant H. contortus larvae and fed sainfoin pellets had faecal egg counts 50% lower than infected lambs fed a control diet [9]. Multispecies swards (like those supported in a herbal ley) containing these plant species and others have been demonstrated to reduce parasite burdens in livestock. This may be because these diverse swards contain anthelmintic compounds [10]. Diverse swards have been shown to reduce the number of anthelmintic treatments required by groups of grazing lambs compared to those grazing a more traditional pasture of perennial ryegrass and clover [11].

Pasture which contains trees suitable for browsing (silvopasture) may also have beneficial effects on parasite burdens in ruminants. Willow trees (Salix spp.) contain condensed tannins and a study found that lambs fed willow had reduced burdens of H. contortus and T. circumcincta [12]. Other ‘regenerative’ strategies for parasite management are under investigation with a fungi, Duddingtonia flagrans, showing potential as an anthelminthic food additive [13]. Trials are planned to take place in Scotland with the SRUC later this year and the researchers are looking for volunteer farms [14]. For those that are not able to make radical changes to their sward type, long rest periods of two to six months on a rotational grazing system have been shown to reduce pasture worm burdens [15, 16]. This may suit farms which mob graze and have a large enough acreage to support such a long rotation.

Resistance and resilience to parasites are heritable traits and selecting for these genes is another route for farms looking to manage their parasite burden in a sustainable way. However, this requires excellent records and single sire mating groups, and the effect will likely take many years to emerge in a closed flock producing their own replacements [17].

When livestock have to be treated, pour on or injectable anthelmintics are preferable to boluses as they have reduced persistence in faeces, and avermectins should be avoided as much as possible [18]. Treated animals should ideally be housed for a short period to avoid spreading resistant worms around the farm and to protect invertebrates from anthelmintic residues. Standard advice published by SCOPS and COWS regarding weighing stock, performing faecal egg counts, resistance testing, and having a refugia population remains the cornerstone of good parasite management planning and does not conflict with alternative methods discussed above. Indeed, faecal egg counts are an excellent starting point when working with farmers trying out regenerative practices, as efficacy of different approaches can be monitored.

The nutritional benefits of diverse pastures

In addition to their potential anthelminthic properties, more diverse pastures may offer the potential of improved mineral and nutrient profiles, with chicory, ribgrass, sheep’s parsley, yarrow, and burnet being deep rooted and bringing up calcium, copper, sodium, iron, phosphorus, magnesium, and potassium from the soil. Lucerne, clovers, and sainfoin are high in protein, and plants containing condensed tannins such as birdsfoot trefoil, and leaves from ash, lime, and mulberry trees bind protein in the rumen, allowing increased protein absorption in the intestines [19, 20, 21, 23]. Willow can provide zinc, selenium, and vitamin E and browsing can make up to 55% of the diet for cattle and up to 76% for sheep [23]. Bella Lowes, a farmer in Devon, noticed a calf with joint ill browsing willow preferentially over the pasture, and Nikki Yoxall, a farmer in North East Scotland sees her cattle preferentially browsing hawthorn, birch, and rowan at different times of the year. Livestock may select plant species containing active compounds such as condensed tannins and naturally occurring antimicrobials [10, 25,26].

Floodplain meadows provide multiple ecosystem services and studies have found that they ​can store more soil carbon than ​some forest​s, but also provide nutrient rich hay for the winter period, for both housed and outwintered cattle [22]. In fact, such meadows must be cut to maintain them and are therefore an excellent option for winter feed. ​Floodplain meadows gain nutrients from flood sediments and ecologist Vicky Bowskill’s research ​is looking at how these nutrients are absorbed by plants during the summer to find the optimal time to cut hay to prevent grass species dominating over flowers and herbs.

Maximising performance and health with regenerative agriculture

Diverse pastures can provide increased resilience to grazing, providing sward cover during periods of adverse weather. They can also provide higher crude protein than limited species grass swards [27]. Ewes grazing multispecies swards can have greater liveweights, can maintain their body condition between lambing and weaning, have higher ovulation rates, lower neonatal mortality, and faster growing lambs compared to ewes grazing perennial ryegrass [11, 28]. Increased finishing weights and average daily gains have been demonstrated in beef grazing birdsfoot trefoil, and in beef and sheep grazing chicory [29,30,31,32]. Dairy cows can produce well with increased variety of grazing, with cattle grazing white clover and birdsfoot trefoil producing higher milk yields compared to cattle grazing grass pastures [19,30]. Rotational grazing increases productivity of pastures, and farmer George Hosier noted that moving cattle between paddocks frequently offered an opportunity to record weights and monitor growth as they passed through the yard [24].

Silvopasture provides shade under trees and provides lower air temperatures than open pasture, provides shelter during wet and windy weather, and contrary to common belief, has not been shown to increase the risk of myiasis [35]. Studies have found lower respiratory rates, body temperatures, and higher rumination rates of cattle and sheep in silvopasture compared to open pasture [33,34].

Breeding for health is essential for regenerative agriculture systems. Adaptability to climate and reproductive fitness are traits identified as important for low input systems [36]. Although there can be challenges in sustaining highly productive dairy cattle on pasture, there can also be associated health benefits such as reduced clinical mastitis and lameness incidence, and therefore those considering making more use of diverse grazing for dairy cows may find a reduction in production diseases [41,42]. Genomic tools can identify cows with high genetic immunity to mastitis, displaced abomasum, metritis, and retained foetal membranes, and when combined into estimated breeding values, the use of such tools can support holistic selection for ‘healthy’ cattle [37]. Cross breeding increases the genetic diversity available in the herd and provides hybrid vigour [38]. In dairy cattle this can increase milk yield and quality by up to 6% and fertility and longevity by up to 15% [39]. Overall, genetic diversity is prized, with attempts at commercially standardizing a ‘type’ of animal suited to regenerative farming seen as antithetical to the principles of continual adaptation in accordance with the specific local environment [36].

The Pasture Fed Livestock Association surveyed 59 pasture feeding farmers in 2018 and reported that 66% of respondents felt that their livestock health had improved following conversion from their previous management system. Farmer Sam Newington found that he was using less antibiotics, wormers, and flukicides since transitioning to regenerative farming, and farmer Chris Brown has also seen his medicine use fall which he attributes to the extended grazing season and consequent decreased risk of respiratory disease outbreaks. Pen Rashbass farms regeneratively by grazing diverse pastures with her flock of Hebridean sheep and follows strict biosecurity and culling protocols to maintain a high health status. The flock was analysed as part of a research project on footrot conducted by the University of Warwick and all samples taken were found to be free of the causative bacteria. For some, regenerative approaches will lead to a change in production methods towards low input, and this may require a careful breed selection and a transition of the breeding stock. In some systems, livestock may be seen more as land management tools, with income from customers attracted by the farm’s environmental and welfare credentials. As such, small, stocky, slow growing (sometimes native or rare) breeds can be better suited to year round grazing and therefore may be preferred [40]. For example Grimblethorpe Hall Estate in Lincolnshire favour their herd of Original population of Lincoln red cattle due to their long coats suitable for outwintering and their ease of calving. Strengthening desired traits in the herd requires an understanding of what the breeding aims are, and it may be that preserving rare genetics is a priority over production traits in some systems. However, breeding for resilience is a necessity, and production traits need not be sacrificed with careful breeding selection.

So what can vets provide to livestock farmers practising regenerative agriculture?

The end results of the new Agriculture Bill are far from certain at the time of writing, but it is clear that ‘public goods’ – clean air, water, biodiversity, and animal welfare – are going to play an important role and many farmers may look at adapting their farm business plans accordingly. With the development of intensive livestock farming, vets found opportunities to become integral to the farm team by interpreting performance data for clients. Similar opportunities exist with regenerative farmers as vets can have an invaluable role as advisors during transition periods, providing guidance for maximising animal welfare as systems change. Such advice may cover:

• Recommendations for providing shade, shelter, and clean water to rotational grazing paddock systems
• Creating integrated parasite management plans
• Comprehensive herd health planning taking into account relevant welfare measures when using pasture feeding and outwintering
• Nutritional monitoring and advice as transitions are made on farm
• Manure scoring and soil invertebrate counts as well more standard production and health measures
• Supporting breeding choices and strategies
• Biosecurity and managing wildlife–livestock interactions

Opportunities may exist relating to meeting supermarket contract requirements or farm assurance schemes that require monitoring of environmental biodiversity and soil health, with support available from some regional wildlife and river trusts. Arable farms looking to improve their soil health may investigate integrating livestock into their crop rotations, thus providing grazing opportunities to livestock farmers, and vets are well placed to facilitate these networks and provide advice.

When working with farmers who have already established regenerative systems, it is essential to understand their goals and work with them. If a farmer is the only person in the area to be using regenerative practices, they may feel that there is a lack of understanding between themselves, their peers, and their vet. By engaging with their goals, stronger relationships can be fostered to ensure that farmers put trust in veterinary services making vets the first port of call for information.

“Having a dialogue is really important. Don’t claim to be an expert or impose a diagnosis without asking questions about the farm’s system which may be different to others in the area. There is space for vets to engage with farmers in a coaching way rather than giving answers all the time.” - Nikki Yoxall, Howemill

“I think there is an opportunity for vets to be more involved in developing holistic herd and flock health plans that minimise the use of any medicines that may affect the environment”- Pen Rashbass, conservation grazier

“Our vets are really interested in our farm! They’re good but I like having the final say. They’re keen to treat the whole herd when one individual is affected and remind me of agronomists pushing chemical sales rather than looking at the whole system.” - Sam Newington, Linden Brook Organics

“Now we’ve proven that our system works, the vets think it’s great. They help with management tasks such as body condition scoring on the second part of TB visits and provide performance data analysis.” – Chris Brown, Elms Farm

Before embarking on regenerative agriculture work, it is advised to speak to consultants already working in the field and perhaps undergo some training. Having the right mentality is essential as there is the risk that practices will not be beneficial unless the whole farm team is on board and understands the underlying principles. Flexibility is key and every farm will need to adapt practices to suit their system. The vet’s role is to advise of risks, stepping in if animal welfare is compromised, and providing support as the farm transitions and establishes.

Livestock health risks to be aware of:

• Excess intake of plants containing secondary metabolites may lead to poisoning. Ensure fields have enough pasture cover and are balanced to meet nutritional requirements

• Outwintering can lead to weight loss and reduced immunity in frail animals. Select stock breed and fitness carefully, always provide shelter, and have housing available if animals become ill

• Adverse weather events may lead to reduced pasture yields and farmers should have back up plans for sourcing forage and feed if necessary. Water and shelter are essential in every field
• Ensure than herd health plans outline preventative health care and treatment options to be used when necessary

A final word from some vets who are leading the way with supporting their clients with their regenerative agriculture aims

Alexandra Tomlinson, wildlife Vet, Consultant for Wilderculture and Chair of the Vet Sustain Food and Farming Working Group, articulates that regenerative agriculture is a complex subject and to fully benefit from the practices used you must work on having a holistic mindset that embraces complex systems. Truly understanding the nutritional needs of ruminants is an essential part of ensuring their health; well planned grazing of diverse pastures can provide a wide range of nutrients, allow the expression of natural selective feeding behaviours and self-medication, and produce nutrient dense food.

Rob Howe is a practising farm Vet and founding Clinical Director at LLM Farm Vets. He is a member of the Vet Sustain Food and Farming Working Group and believes passionately that vets have the potential to provide gateways for understanding and engagement around issues which involve the environment, animal & human health. Rob has been developing vet services for regenerative and conventional farming clients alike, asserting that vets adopting these principles will lead the way in promoting animal health and welfare within sustainable and regenerative farming systems, providing great benefits for the whole of society.

This is a developing field with new research coming to the fore, providing an exciting opportunity for vets to promote livestock health as integral to a healthy environment for all.

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Acknowledgement and thanks to Laura Higham, Amy Jennings, Alexandra Tomlinson, Rob Howe, John Meadley and the Pasture Fed Livestock Association, Catherine Booty, Vicky Bowskill, Chris Brown, Grimblethorpe Hall Estate, George Hosier, Bella Lowes, Sam Newington, Pen Rashbass, and Nikki Yoxall for their valued contributions.

An abridged version of this article has been published by the Vet Record. Read more here.

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