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Updated: 57 min 47 sec ago

Pork labelling schemes ‘not helpful’ in making informed buying choices, say researchers

Thu, 11/04/2024 - 10:27

Researchers have evaluated different types of pig farming – including woodland, organic, free range, RSPCA assured, and Red Tractor certified, to assess each systems’ impact across four areas: land use (representing biodiversity loss), greenhouse gas emissions, antibiotics use and animal welfare. Their study concludes that none of the farm types performed consistently well across all four areas – a finding that has important implications for increasingly climate conscious consumers, as well as farmers themselves.

However, there were individual farms that did perform well in all domains, including an indoor Red Tractor farm, an outdoor bred, indoor finished RSPCA assured farm and fully outdoor woodland farm. “Outliers like these show that trade-offs are not inevitable,” said lead author Dr Harriet Bartlett, Research Associate at the University of Oxford's Smith School of Enterprise and the Environment, who was formerly at the University of Cambridge.  

“Somewhat unexpectedly we found that a handful of farms perform far better than average across all four of our environmental and welfare measures,” added senior author Andrew Balmford, Professor of Conservation Science at the University of Cambridge. However, none of the current label or assurance schemes predicted which farms these would be.

“The way we classify farm types and label pork isn’t helpful for making informed decisions when it comes to buying more sustainable meat. Even more importantly, we aren’t rewarding and incentivising the best-performing farmers. Instead of focusing on farm types or practices, we need to focus on meaningful outcomes for people, the planet and the pigs – and assess, and reward farms based on these,” said Bartlett.

The findings also show that common assumptions around food labelling can be misplaced. For instance, Organic farming systems, which consumers might see as climate and environmentally friendly, have on average three times the CO2 output per kg of meat of more intensive Red Tractor or RSPCA assured systems and four times the land use. However, these same systems use on average almost 90% fewer antibiotic medicines, and result in improved animal welfare compared with production from Red tractor or RSPCA assured systems.

The way we classify livestock farms must be improved, Bartlett says, because livestock production is growing rapidly, especially pork production, which has quadrupled in the past 50 years and already accounts for 9% of greenhouse gas emissions from livestock. Pig farming also uses more antibiotics than any other livestock sector, and 8.5% of all arable land.

“Our findings show that mitigating the environmental impacts of livestock farming isn’t a case of saying which farm type is the best,” said Bartlett. “There is substantial scope for improvement within types, and our current means of classification is not identifying the best farms for the planet and animals overall. Instead, we need to identify farms that successfully limit their impacts across all areas of societal concern, and understand, promote and incentivise their practises.”

The study reached its conclusions using data from 74 UK and 17 Brazilian breed-to-finish systems, each made up of 1-3 farms and representing the annual production of over 1.2 million pigs. It is published today in the journal Nature Food.

“To the best of our knowledge, our dataset covers by far the largest and most diverse sample of pig production systems examined in any single study,” said Bartlett.

James Wood, Professor of Equine and Farm Animal Science at the University of Cambridge, commented: “This important study identifies a key need to clarify what different farm labels should indicate to consumers; there is a pressing need to extend this work into other farming sectors. It also clearly demonstrates the critical importance that individual farmers play in promoting best practice across all farming systems.”

Trade-offs in the externalities of pig production are not inevitable was authored by academics at the University of Oxford, University of Cambridge and the University of São Paulo.

The research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC).

Reference: Bartlett, H.,‘Trade-offs in the externalities of pig production are not inevitable.’ Nature Food, April 2024. DOI: 10.1038/s43016-024-00921-2

Adapted from a press release by the University of Oxford.

Farmers don’t have to choose between lowering environmental impact and improving welfare for their pigs, a new study has found: it is possible to do both. But this is not reflected in the current food labelling schemes relied on by consumers.

The way we classify farm types and label pork isn’t helpful for making informed decisions when it comes to buying more sustainable meat.Harriet BartlettCharity Burggraaf/ GettyTwo pigs on a farm


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TB vaccine may enable elimination of the disease in cattle by reducing its spread

Thu, 28/03/2024 - 18:00

The research, led by the University of Cambridge and Penn State University, improves prospects for the elimination and control of bovine tuberculosis (TB), an infectious disease of cattle that results in large economic costs and health impacts across the world.  

This is the first study to show that BCG-vaccinated cattle infected with TB are substantially less infectious to other cattle. This remarkable indirect effect of the vaccine beyond its direct protective effect has not been measured before.

The spillover of infection from livestock has been estimated to account for about 10% of human tuberculosis cases. While such zoonotic TB (zTB) infections are most commonly associated with gastro-intestinal infections related to drinking contaminated milk, zTB can also cause chronic lung infections in humans. Lung disease caused by zTB can be indistinguishable from regular tuberculosis, but is more difficult to treat due to natural antibiotic resistance in the cattle bacteria.

TB remains endemic in many countries around the world, including in Europe and the Americas, where its control costs farmers and taxpayers hundreds of millions of dollars each year.

The study is published today in the journal Science.

In the study, carried out in Ethiopia, researchers examined the ability of the vaccine, Bacillus Calmette-Guérin (BCG), to directly protect cattle that receive it, as well as to indirectly protect both vaccinated and unvaccinated cattle by reducing TB transmission. Vaccinated and unvaccinated animals were put into enclosures with naturally infected animals, in a novel crossover design performed over two years.

“Our study found that BCG vaccination reduces TB transmission in cattle by almost 90%. Vaccinated cows also developed significantly fewer visible signs of TB than unvaccinated ones. This suggests that the vaccination not only reduces the progression of the disease, but that if vaccinated animals become infected, they are substantially less infectious to others,” said Andrew Conlan, Associate Professor of Epidemiology at the University of Cambridge’s Department of Veterinary Medicine and a corresponding author of the study.

Using livestock census and movement data from Ethiopia, the team developed a transmission model to explore the potential for routine vaccination to control bovine tuberculosis.

“Results of the model suggest that vaccinating calves within the dairy sector of Ethiopia could reduce the reproduction number of the bacterium — the R0 — to below 1, arresting the projected increase in the burden of disease and putting herds on a pathway towards elimination of TB,” Conlan said.

The team focused their studies in Ethiopia, a country with the largest cattle herd in Africa and a rapidly growing dairy sector that has a growing burden of bovine tuberculosis and no current control program, as a representative of similarly situated transitional economies.

“Bovine tuberculosis is largely uncontrolled in low- and middle-income countries, including Ethiopia,” said Abebe Fromsa, associate professor of agriculture and veterinary medicine at Addis Ababa University in Ethiopia and the study’s co-lead author. “Vaccination of cattle has the potential to provide significant benefits in these regions.”

“For over a hundred years, programs to eliminate bovine tuberculosis have relied on intensive testing and slaughtering of infected animals,” said Vivek Kapur, professor of microbiology and infectious diseases and Huck Distinguished Chair in Global Health at Penn State and a corresponding author of the study.

He added: “This approach is unimplementable in many parts of the world for economic and social reasons, resulting in considerable animal suffering and economic losses from lost productivity, alongside an increased risk of spillover of infection to humans. By vaccinating cattle, we hope to be able to protect both cattle and humans from the consequences of this devastating disease.”

Professor James Wood, Alborada Professor of Equine and Farm Animal Science in the University of Cambridge’s Department of Veterinary Medicine, noted that despite TB being more prevalent in lower-income countries, the United Kingdom, Ireland and New Zealand also experience considerable economic pressures from the disease which continues to persist despite intensive and costly control programs.

Wood said: “For over twenty-years the UK government has pinned hopes on cattle vaccination for bovine tuberculosis as a solution to reduce the disease and the consequent costs of the controls. These results provide important support for the epidemiological benefit that cattle vaccination could have to reduce rates of transmission to and within herds.”

This research was supported by The Bill & Melinda Gates Foundation, as well as the Biotechnology and Biological Sciences Research Council; Foreign, Commonwealth and Development Office; Economic & Social Research Council; Medical Research Council; Natural Environment Research Council; and Defence Science & Technology.

Reference: Fromsa, A. et al: ‘BCG vaccination of cattle reduces transmission of bovine tuberculosis, improving the prospects for elimination.’ Science, March 2024. DOI: 10.1126/science.adl3962

Vaccination not only reduces the severity of TB in infected cattle, but reduces its spread in dairy herds by 89%, research finds.

Our study suggests that vaccination not only reduces the progression of the disease, but that if vaccinated animals become infected, they are substantially less infectious to others.Andrew ConlanGetty/ kamisokaHerd of cows in a grassy field


The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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Genetic mutation in a quarter of all Labradors hard-wires them for obesity

Wed, 06/03/2024 - 19:06

This obesity-driving combination means that dog owners must be particularly strict with feeding and exercising their Labradors to keep them slim.

The mutation is in a gene called POMC, which plays a critical role in hunger and energy use.

Around 25% of Labradors and 66% of flatcoated retriever dogs have the POMC mutation, which researchers previously showed causes increased interest in food and risk of obesity.

The new study reveals how the mutation profoundly changes the way Labradors and flatcoated retrievers behave around food. It found that although they don’t need to eat more to feel full, they are hungrier in between meals.

In addition, dogs with the POMC mutation were found to use around 25% less energy at rest than dogs without it, meaning they don’t need to consume as many calories to maintain a healthy body weight.

“We found that a mutation in the POMC gene seems to make dogs hungrier. Affected dogs tend to overeat because they get hungry between meals more quickly than dogs without the mutation,” said Dr Eleanor Raffan, a researcher in the University of Cambridge’s Department of Physiology, Development and Neuroscience who led the study.

She added: “All owners of Labradors and flatcoated retrievers need to watch what they’re feeding these highly food-motivated dogs, to keep them a healthy weight. But dogs with this genetic mutation face a double whammy: they not only want to eat more, but also need fewer calories because they’re not burning them off as fast.”

The POMC mutation was found to alter a pathway in the dogs’ brains associated with body weight regulation. The mutation triggers a starvation signal that tells their body to increase food intake and conserve energy, despite this being unnecessary.

The results are published today in the journal Science Advances.

Raffan said: “People are often rude about the owners of fat dogs, blaming them for not properly managing their dogs’ diet and exercise. But we’ve shown that Labradors with this genetic mutation are looking for food all the time, trying to increase their energy intake. It’s very difficult to keep these dogs slim, but it can be done.”

The researchers say owners can keep their retrievers distracted from this constant hunger by spreading out each daily food ration, for example by using puzzle feeders or scattering the food around the garden so it takes longer to eat.

In the study, 87 adult pet Labrador dogs - all a healthy weight or moderately overweight - took part in several tests including the ‘sausage in a box’ test.

First, the dogs were given a can of dogfood every 20 minutes until they chose not to eat any more. All ate huge amounts of food, but the dogs with the POMC mutation didn’t eat more than those without it. This showed that they all feel full with a similar amount of food.

Next, on a different day, the dogs were fed a standard amount of breakfast. Exactly three hours later they were offered a sausage in a box and their behaviour was recorded. The box was made of clear plastic with a perforated lid, so the dogs could see and smell the sausage, but couldn’t eat it.

The researchers found that dogs with the POMC mutation tried significantly harder to get the sausage from the box than dogs without it, indicating greater hunger.

The dogs were then allowed to sleep in a special chamber that measured the gases they breathed out. This revealed that dogs with the POMC mutation burn around 25% fewer calories than dogs without it.

The POMC gene and the brain pathway it affects are similar in dogs and humans. The new findings are consistent with reports of extreme hunger in humans with POMC mutations, who tend to become obese at an early age and develop a host of clinical problems as a result.

Drugs currently in development for human obesity, underactive sexual desire and certain skin conditions target this brain pathway, so understanding it fully is important.

A mutation in the POMC gene in dogs prevents production of two chemical messengers in the dog brain, beta-melanocyte stimulating hormone (β-MSH) and beta-endorphin, but does not affect production of a third, alpha-melanocyte stimulating hormone (α-MSH).

Further laboratory studies by the team suggest that β-MSH and beta-endorphin are important in determining hunger and moderating energy use, and their role is independent of the presence of α-MSH. This challenges the previous belief, based on research in rats, that early onset human obesity due to POMC mutations is caused only by a lack of α-MSH. Rats don’t produce beta-melanocyte stimulating hormone, but humans and dogs produce both α- and β-MSH.

The research was funded by The Dogs Trust and Wellcome.

Reference: Dittmann, M T et al: ‘Low resting metabolic rate and increased hunger due to β-MSH and β-endorphin deletion in a canine model.’ Science Advances, March 2024. DOI: 10.1126/sciadv.adj3823

New research finds around a quarter of Labrador retriever dogs face a double-whammy of feeling hungry all the time and burning fewer calories due to a genetic mutation.

Labradors with this genetic mutation are looking for food all the time, trying to increase their energy intake. It’s very difficult to keep these dogs slim, but it can be done.Eleanor Raffan A quarter of Labradors are hard-wired for obesity Jane GoodallLabrador retriever dog


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