Alasdair worked in Scotland, Wales and New Zealand before joining Synergy Farm Health in 2013. He has since completed a MSc in International Animal Health, and has a keen interest in future food security. He is a director of VetSalus, a global network of veterinary consultants working with food producers to improve animal health, welfare and sustainability.

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Whilst global predictions suggest a 70% increase in demand for meat by 2050, we would agree with Professor Pete Smith (University of Aberdeen) that in developed countries, it will not in future be possible for everyone to eat as much meat as is currently eaten per head of population. However, we view this as an opportunity for high welfare, well-managed livestock to take a greater share of the marketplace, by steering consumers towards higher quality products. To achieve this, farming needs to be confident of its sustainability credentials, and as vets we can support farmers to ensure their enterprises are efficient, profitable, and fit for the future.

Appropriate use of medicines

• Appropriate use of antimicrobials is essential to mitigate the development of antimicrobial resistance – aiming to use them “as little as possible but as much as necessary”. While the ruminant sector is considered a low user of antimicrobials, it is vital that you work with your vet to collate and record your annual use of such drugs within your health plan. This simple step is important to make sure these medicines are still available for us in the future.

• It is worth remembering that any worming or fluke product will work within cattle and sheep but also in the environment they are excreted into. Use of ivermectin products has been widely shown to incapacitate dung beetles at concentrations lower than those usually measured in the dung of treated livestock. Dung beetles can be viewed as the unsung heroes of our environment, with their ability to recycle nutrients via burying of soil or carrion, and by removing dung from pasture which prevents populations of parasitic flies from breeding in fresh faeces. The use of selective deworming, and routine use of faecal egg counts (both to be aware of the livestock burden and the likely pasture burden) are key tools that have both an environmental and economic benefit.

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Age of first calving

• While ruminants provide high quality protein essential for human diets, they are an important source of greenhouse gas (GHG) emissions – in particular, methane. For all livestock, the cost of production and lifetime ruminant GHG emission is influenced greatly by the age of first calving or lambing. A beef calf is ideally weaned (and therefore commence eructating) at 200 days; a heifer that calves for the first time at 2 years will therefore have been emitting GHG’s for 530 days before producing a calf that is destined to enter the food chain, whilst an animal that calves for the first time at 3 years will have been emitting GHG’s for 895 days. Our consideration of GHG emissions also parallels what we already know regarding overall lifetime efficiency of heifers calving at 3 years of age compared with calving heifers at two years old. (7% lower for those calving at 3 years old).

• Alternatively, if there are two herds (one calving in the autumn and the other in the spring) then one can provide replacements for the other. This would allow the heifers to calve down at 28-30 months reducing the inefficiency associated with calving at three years while allowing the beef heifer more time to reach an adequate weight and maturity before calving. This is likely to be of particular benefit where heifer replacements are being reared in the hill environment.

Optimising animal health and nutrition

• Controlling endemic diseases and syndromes such as Johne’s, Salmonella, BVD, infertility, fluke, IBR, lameness and mastitis have been shown to reduce GHG emissions in cattle by up to 25%. Controlling such issues also contributes to improved welfare and, ultimately, productivity and profitability.

• Cattle fed maize silage rather than grass silage, and sheep fed on higher sugar grass, produce lower amounts of methane (Defra, 2010). There appears to be a direct relation¬ship between dry matter content of ruminant diets and the methane produced (SRUC, 2015). Unfortunately, this can’t be considered in isolation, as we also need to be aware of the environmental cost of either reseeding pasture or ploughing fields for crop. However, work is ongoing to help us understand more about how the cow, the rumen and its microbes influence methane production.

We live in a time of unprecedented environmental threat. If our veterinary advice continuously prioritises reducing the environmental impact of the animals we look after, in addition to all the more traditional considerations, we will be well on the way to fulfilling our ambition to “play a more active role in the sustainability agenda” (Robinson et al., 2019).

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