Bristol East MP Kerry McCarthy is doomed to failure in her role as shadow secretary of state for the environment, food and rural affairs. That’s the word coming out of Ukip’s camp on her appointment to Jeremy Corbyn’s frontbench. “Only he could select a vegan to represent the Labour party on agricultural matters,” Stuart Agnew, a Ukip spokesman, said. “Kerry McCarthy will have little in common with either the producers or consumers of food and would be better described as the Corbynist who would like Defra to be renamed the Department for Eradication of Farmers and Rural Areas.”

What Agnew and other detractors have failed to grasp is this: most vegans have emphatically chosen to disengage with the meat and dairy industries because they deem the standards of rearing and slaughtering animals for food too low. This is not a simple kneejerk, emotional reaction – it is a rational and pragmatic decision based on research and a refusal to subsidise increasingly brutalised methods of industrial food production.

In addition, there is a lack of transparency when it comes to livestock standards. And judging by the vegan MP’s comments, it is a commitment to improving these standards that will form the cornerstone of her brief. Describing her veganism as her own personal views, she went on to say: “In terms of Labour party policy, promoting animal welfare is something we have always done as is promoting sustainable farming. I’m personally happy working with farmers.”

Most people – with the exception of extremist blood sport advocates – do not enjoy the idea of animals being tortured, and killed in the appalling conditions that exist in some slaughterhouses. I believe the vast majority of the meat-eating British public would welcome better welfare standards and clearer food labelling.

By calling her ideals unscientific, critics risk alienating large swaths of the public who agree with McCarthy

Looking at data from the retail sector of the egg market, 52% of eggs purchased last year were free-range, with 3% barn-laid, and 45% from chickens in “enriched cages”. This suggests that there is an interest in animal welfare, with a small majority of consumers using food labelling to pick the more ethical, and correspondingly more expensive, product.

In fact farmers themselves stand to benefit from the better conditions McCarthy will be keen to champion. A 2010 report by the National Farmers’ Union made clear the vital link between animal wellbeing in the dairy sector and milk production. Not only are there potential fiscal benefits to improving the lives of these animals, the farm animal welfare committee, an advisory body to Defra, is currently committed to investigating what it describes as “possible links between the wellbeing of farmers and the welfare of their livestock”.

If McCarthy’s passion for the treatment of animals can translate into both pastoral and economic benefits for the sector, surely her lifestyle is to be commended, and not derided by people such as Mike King, vice chairman of the Royal Association of British Dairy Farmers, who said: “Her ideals are based on emotion rather than scientific fact.”

McCarthy’s campaigning in the past has focused on the highly unpopular and inefficient badger cull, as well as animal experimentation, animals in circuses and foxhunting, which continues to face huge public opposition. These are all mainstream causes. By trying to marginalise her ideals as unscientific, these critics risk alienating large swaths of the public who agree with McCarthy on a number of issues.

Not least of these is the environment – and while the tabloid press has had a field day with screeching headlines about her belief that beef farming is unsustainable, it has overlooked one hugely important fact. Methane emissions from animal agriculture are a massive factor in global warming (19% of total global greenhouse emissions).

According to a report released by the United Nations this year the world can expect a global population of more than nine billion by 2050. Describing current global consumption of meat and dairy as “unsustainable”, the report says: “Impacts from agriculture are expected to increase substantially due to population growth increasing consumption of animal products. Unlike fossil fuels, it is difficult to look for alternatives: people have to eat. A substantial reduction of impacts would only be possible with a substantial worldwide diet change, away from animal products.”

To have a shadow environment secretary who understands this smacks not of emotional silliness as has been suggested, but of an inherent and serious commitment to the global landscape and farming sector.